Basic Science (24

MULTIDISCIPLINARY ABSTRACTS

© 2001 Blackwell Science Inc., 1530–7085/01/$15.00Pain Practice, Volume 1, Number 1, 2001 84–118

that the laterally directed cervical epidural catheter was an ef-fective technique to produce continuous unilateral analgesiaand sympathetic block.

Anesthesia (3)

Anton G.L. Burm, Rudolf Stienstra, Rolf P. Brouwer, Britt-

Marie Emanuelsson, Jack W. van Kleef:

Epidural infusion ofropivacaine for postoperative analgesia after major orthopedicsurgery. (Leiden University Medical Center, Leiden, The Neth-erlands)

Anesthesiology

2000;93:395–403.

This study evaluated the pharmacokinetics of ropivacaine ad-ministered by 72-h epidural infusion to provide postoperativeanalgesia. Twenty-eight patients scheduled for major orthope-dic surgery during combined epidural and general anesthesiareceived a bolus dose of ropivacaine (50 or 70 mg), followedby constant-rate (10 mL/h) epidural infusion of ropivacaine2 mg/mL (Group 1) or 3 mg/mL (Group 2). Total and un-bound plasma concentrations of ropivacaine and pipecoloxyli-dide and plasma concentrations of

a

1

-acid glycoprotein weredetermined. The urinary excretion of ropivacaine and majormetabolites was measured. Results showed that total plasmaconcentrations of ropivacaine increased steadily during infu-sion and unbound ropivacaine concentrations reached average

steady levels of approximately 0.06 and 0.07 mg/l. Total and

unbound concentrations of pipecoloxylidide increased to 1.0

6

0.4 and 0.4

6

0.2 mg/l (Group 1) and 1.2

6

0.4 and 0.5

6

0.1 mg/l (Group 2) after 72 h infusion.

a

1

-Acid glycoproteinconcentrations initially decreased, but thereafter increased steadilyto approximately twice the baseline values. Conclude postopera-

tive increases in plasma

a

1

-acid glycoprotein concentrations en-hance the protein binding of ropivacaine and pipecoloxylidide,which causes divergence of total and unbound plasma concentra-tions.

Anesthesia (4)

Bruno Guignard, Anne Elisabeth Bossard, Carole Coste et al:

Intraoperative remifentanil increases postoperative pain andmorphine requirement. (Hôpital Ambroise Paré, Boulogne-Bil-lancourt, France)

Anesthesiology

2000;93:409–417.

The study tested the hypothesis that intraoperative remifenta-nil administration results in acute opioid tolerance that is man-ifested by increased postoperative pain and opioid require-ment. Fifty adult patients undergoing major abdominal surgerywere randomly assigned to 2 anesthetic regimens: (1) the remifen-tanil group or (2) the desflurane group. All patients were given abolus of 0.15 mg/kg morphine 40 min before the end of sur-gery. Morphine was initially titrated to need by postanesthesia

Anesthesia (1)

Farrokh R. Maneksha, Himayun Mirza, Paul J. Poppers:

Complex regional pain syndrome (CRPS) with resistance to lo-cal anesthetic block: a case report. (State University of NewYork at Stony Brook, Stony Brook, NY)

J Clin Anesth

2000;12:67–71.

A case of complex regional pain syndrome (CRPS) Type 1 ina 12-year-old girl is presented. The patient did not respondto the usual therapeutic modalities used to treat CRPS in-cluding physical therapy, lumbar sympathetic block, epidu-ral local anesthetic block, intravenous lidocaine infusion, orother oral medications. Of note is the fact that during epidu-ral block the patient demonstrated a resistance to local anes-thetic neural blockade in the area of the body involved withthe pain problem. The mechanism of this resistance could berelated to the changes in the dorsal horn cells of the spinalcord, secondary to activation of N-methyl-D-aspartate recep-tors, which may play a role in the pathophysiology of this painsyndrome.

Anesthesia (2)

Thomas Buchheit, James C. Crews:

Lateral cervical epiduralcatheter placement for continuous unilateral upper extremityanalgesia and sympathetic block. (Wake Forest UniversitySchool of Medicine, Winston-Salem, NC)

Reg Anesth PainMed

2000;25:313–317.

This article discussed the use of a laterally directed cervicalepidural catheter for the treatment of acute and chronic pain.The technique was used in a series of 30 patients to produceunilateral upper extremity analgesia and sympathetic block. Acase report of a patient treated with this technique and a de-scription of the technique as well as the results from the seriesare presented. The method included placement of an epiduralcatheter at the C6-7 vertebral interspace; the needle bevel andcatheter were directed to the affected side in a woman with ahistory of complex regional pain syndrome of the right upperextremity. A unilateral block was shown with the technique byanatomic parameters (unilateral contrast dye spread), physio-logic parameters (unilateral Horner’s syndrome), and symp-tomatic parameters (unilateral, subjective neural block). Onepatient treated with the technique had bilateral effects; how-ever, no patient had a predominant block on the contralateralside and no complications developed. The case report showedresults that were typical of the series of 30 patients. Conclude

Multidisciplinary Abstracts

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85

care nurses blinded to group assignment. Subsequently, pa-tients—who were blinded to group assignment—controlledtheir own morphine administration. Pain scores and morphineconsumption were recorded for 24 postoperative h. The re-sults indicated that the mean remifentanil infusion rate was0.3

6

0.2

m

g

?

kg

2

1

?

min

2

1

in the remifentanil group, whichwas significantly greater than in the desflurane group. Intraop-erative hemodynamic responses were similar in each group.Postoperative pain scores were significantly greater in theremifentanil group. These patients required morphine signifi-cantly earlier than those in the desflurane group and needednearly twice as much morphine in the first 24 postoperative h:59 mg (25% to 75% interquartile range, 43–71) versus 32 mg(25% to 75% interquartile range, 19–59;

P

,

0.01). Concludethat relatively large-dose intraoperative remifentanil increasedpostoperative pain and morphine consumption. These datasuggest that remifentanil causes acute opioid tolerance and hy-peralgesia.

Anesthesia (5)

A. Montes, W. Warner, M.M. Puig:

Use of intravenous patient-controlled analgesia for the documentation of synergy betweentramadol and metamizol. (Hospital Universitario del Mar, Bar-celona, Spain)

Br J Anaesth

2000;85:217–223.

This study involved 101 posthysterectomy patients who re-ceived at the time of analgesia request (TAR) tramadol (100 mg,Group I) or metamizol (1.2 g, Group II) alone, or combinedin 1:1 (Group III), 1:0.3 (Group IV), or 1:3 (Group V) ratio.After 15 min, they received the same treatment by IV patient-controlled analgesia. Pain intensity (VAS-PI), analgesic consump-tion, and adverse effects were assessed at TAR, and periodi-cally for 24 h. Data were analyzed using interaction indexesand isobolograms. All treatments produced equivalent VAS-PI,percent efficacy, and adverse effects; all other treatments wereaddictive.

Comment

by Octavio Calvillo, MD, PhD.Synergistic interactions either beneficial or adverse between

analgesic drugs remains to be studied quantitatively. The au-thors propose a new method to quantitate such interactions;this is based on analgesic requirements (IV-PCA) and pain in-tensity (VAS-PI). Data were analyzed using interaction indexesand isobolograms. Isobols are graphic representations ofequally effective doses of 2 or more agents. The mean doses ofeach drug that produces a given response are plotted on theaxes of the graph. A zero interaction line (isobol) connectsthese isoeffective doses in the axis. Using this approach the au-thors studied 101 posthysterectomy patients. Patients receivedat the time of analgesia request (TAR) tramadol (100 mg,Group I) or metamizol (1.2 g, Group II), alone or combined1:1 (Group III), 1:0.3 (Group IV) or 1:3 (Group V). All treat-ments produced equivalent VAS-PI, percent efficacy, and ad-verse effects. Drugs combined in 1:1 ratio synergy became evi-dent both for the analgesic and adverse effects; all othertreatments were additive.

Anesthesia (6)

P.A. Mallinder, J.E. Hall, F.G. Bergin, P. Royle, D.J. Leaper:

A comparison of opiate- and epidural-induced alterations insplanchnic blood flow using intraoperative gastric tonometry.(North Tees Hospital, Hardwick, Stockton-on-Tees, Cleve-land, UK)

Anaesthesia

2000;55:659–665.

This study assessed the ability of tonometry to measure differ-ential effects of opiate and epidural analgesia on splanchnicblood flow. Forty patients for elective colorectal surgery wererandomly allocated to receive epidural infusion or intravenousmorphine. Gastric mucosal PCO

2

, pHi, standard pHi, PCO

2

gap, and pH gap were measured after induction and on termi-nation of surgery. These parameters were within normal limitsat the end in most cases and there was no significant differencebetween the groups. The complication rate was similar in bothgroups and was not correlated with low pHi, but was corre-lated with blood loss. A difference in splanchnic perfusion wasnot demonstrated between the two groups.

Comment

by Octavio Calvillo, MD, PhD.This study concerns the assessment of splanchnic blood

flow measured indirectly and noninvasively in patients under-going colorectal surgery. The tonometer is a modified gastrictube terminating in a silicone balloon, which can be filled in-termittently with either air or saline. With this technique, it ispossible to measure gastric mucosal CO2 (P

g

CO

2

) and intra-mucosal pH and pH gap using a modified Henderson-Hasell-bach equation, thus indirectly providing an estimate ofsplanchnic blood flow. These parameters were measured afterinduction and upon termination of surgery in 2 groups of pa-tients randomly allocated to receive either intravenous mor-phine (10 mg) or epidural bupivacaine to achieve a T5 sensorylevel of blockade. The authors were unable to demonstrate adifference in splanchnic perfusion as assessed with tonometrybetween the 2 groups.

Anesthesia (7)

François J. Singelyn, Jean-Marie A. Governeur:

Extended “three-in-one” block after total knee arthroplasty: continuous versuspatient-controlled techniques. (St. Luc Hospital, Brussels, Bel-gium)

Anesth Analg

2000;91:176–180.

This prospective, randomized, doubled-blinded study assessedthe efficacy of patient-controlled analgesia (PCA) techniquesfor an extended “3-in-1” block after total knee arthroplasty. Atotal of 45 patients were divided into 3 groups of 15. Over 48 h,all patients received 0.125% bupivacaine with 1

m

g/mL cloni-dine via a femoral nerve sheath catheter in the following man-ner: as a continuous infusion at 10 mL/h in Group 1; as a con-tinuous infusion at 5 mL/h plus PCA boluses (2.5 mL/30 min)in Group 2; or as PCA boluses only (10 mL/60 min) in Group3. Pain scores, sensory block, supplemental analgesia, bupiva-caine consumption, side effects, and satisfaction scores wererecorded. Pain scores and supplemental analgesia were compa-rable in the three groups. Bupivacaine consumption was signif-icantly less in Groups 2 and 3 than in Group 1 (

P

,

0.01), and

86

•

multidisciplinary abstracts

in Group 3 than in Group 2 (

P

,

0.01). Side effects and satis-faction were comparable in the 3 groups. Conclude that ex-tended “3-in-1” block provides efficient pain relief after totalknee arthroplasty and that, compared with a continuous infu-sion, PCA techniques reduce the total anesthetic consumptionwithout compromise in patient satisfaction or visual analogscale scores. Of the 2 PCA techniques tested, PCA boluses(10-mL lockout; time 60 min) of 0.125% bupivacaine with1

m

g/mL clonidine was associated with the smallest local anes-thetic consumption, and is, therefore, the recommended ex-tended “3-in-1” block technique.

Comment

by Octavio Calvillo, MD, PhD.In a prospective, randomized, double-blinded study, the au-

thors studied the efficacy of the 3 in 1 block in a group of pa-tients that had undergone total knee arthroplasty. Patientswere allocated to 3 groups; all patients had a catheter im-planted in the femoral sheath. Over 48 h all patients received0.125% bupivacaine with 1

m

g/mL clonidine. Group 1 re-ceived the mixture as a continuous infusion at 10 mL/h. Group2 received a continuous infusion at 5 mL/h plus PCA boluses(2.5 mL/30 min). Group 3 received 10 mL of solution per60 min. Pain scores, supplemental analgesia side effects, andpatient satisfaction were comparable in all groups. Bupiva-caine consumption was significantly lower in Group 2 andGroup 3 as compared to Group 1 (

P

,

0.01). Of the PCA tech-niques studied, the regimen involving 10 mL per h was associ-ated with the lowest local anesthesia consumption and is,therefore, the recommended technique for extended 3 in 1block.

Anesthesia (8)

Andrea Casati, Guido Fanelli, Paolo Beccaria et al:

The effectsof the single or multiple injection technique on the onset time offemoral nerve blocks with 0.75% ropivacaine. (University ofMilan and IRCCS San Raffaele Hospital, Milan, Italy)

AnesthAnalg

2000;91:181–184.

This study evaluated the effect of the injection technique onthe onset time and efficacy of femoral nerve block performedwith 0.75% ropivacaine. A total of 30 patients undergoing ar-throscopic knee surgery were randomly allocated to receivefemoral nerve blocakade with 0.75% ropivacaine by using ei-ther a single injection (Single group, n

5

15) or multiple injec-tion (Multiple group, n

5

15). Nerve blocks were placed by us-ing a short-beveled, Teflon-coated, stimulating needle. Thestimulation frequency was set at 2 Hz, and the intensity of thestimulating current, initially set at 1 mA, was gradually de-creased to

,

0.5 mA after each muscular twitch was observed.In the Single group, 12 mL of 0.75% ropivacaine was slowlyinjected, as soon as the first muscular twitch was observed. Inthe Multiple group, the stimulating needle was inserted and re-directed, eliciting each of the following muscular twitches:contraction of vastus medialis, vastus intermedius, and vastuslateralis. At each muscular twitch, 4 mL of the study solutionwas injected. Placing the block required 4.2

6

1.7 min in theMultiple group and 3.4

6

2.2 min in the Single group (

P

5

0.02). Onset of nerve block required 10

6

3.7 min in the Mul-tiple group and 30

6

11 min in the Single group (

P

,

0.0005).Propofol sedation was never required to complete surgery; al-though 0.1 mg fentanyl at trocar insertion was required in 2patients of the Multiple group (13%) and 9 patients of the Sin-gle group (60%) (

P

5

0.02). Conclude that searching for mul-tiple muscular twitches shortened the onset time and improvedthe quality of femoral nerve block performed with small vol-umes of 0.75% ropivacaine.

Comment

by Octavio Calvillo, MD, PhD.This study is concerned with the onset of femoral nerve

block utilizing 0.75% ropivacaine in 2 groups of 15 patientsundergoing arthroscopic knee surgery. The optimal site for in-jection was identified by the electrically evoked musculartwitch at the quadriceps. In 1 group, 12 mL of 0.75% ropiva-caine was injected as soon as a muscle twitch was evoked. Inthe second group, 4 mL of local anesthetic was injected onlyafter a specific response was elicited at the vastus medialis,vastus intermedius, and vastus laterallis. Onset of the nerveblock required 10

6

3.7 min. in the multiple injection group,whereas in the single group, onset of the nerve block took30

6

11 min. The authors concluded that searching for multi-ple twitches shortened the surgical anesthesia and improvedthe quality of neural blockade.

Anesthesia (9)

Robert D. Stevens, Elisabeth Van Gessel, Nicolas Flory, Rox-ane Fournier, Zdravko Gamulin:

Lumbar plexus clock reducespain and blood loss associated with total hip arthroplasty.(Hôpitaux Universitaires de Genéve, Geneva, Switzerland)

An-esthesiology

2000;93:115–121.

In this study, 60 patients undergoing total hip arthroplastywere randomized to receive general anesthesia with (plexusgroup, n

5

30) or without (control group, n

5

30) a posteriorlumbar plexus block. The block was performed after inductionusing a nerve stimulator, and 0.4 mL/kg bupivacaine, 0.5%,with epinephrine was injected. General anesthesia was stan-dardized, and supplemental fentanyl was administered per he-modynamic guidelines. Postoperative pain and patient-con-trolled intravenous morphine use were serially assessed for48 h. The proportion of patients receiving supplemental fenta-nyl intraoperatively was more than 3 times greater in the con-trol group (20 of 30 vs. 6 of 29,

P

5

0.001). In the postanes-thesia care unit, a greater than fourfold reduction in painscores was observed in the plexus group and “rescue” mor-phine boluses were administered 10 times less frequently. Painscores and morphine consumption remained significantlylower in the plexus group until 6 h after randomization. Oper-ative and postoperative (48 h) blood loss was decreased mod-estly in the treated group. Epidural-like distribution of anes-thesia occurred in 3 of 28 plexus group patients, but no otherside effects were noted. Conclude that posterior lumbar plexusblock provides effective analgesia for total hip arthroplasty, re-ducing intraoperative and postoperative opioid requirements.


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Blood loss during and after the procedure is diminished. Epi-dural anesthetic distribution should be anticipated in a minorityof cases.

Comment

by Alan David Kaye, MD, PhD.The benefits of regional anesthetic techniques are well es-

tablished for patients undergoing total hip arthroplasty. Forexample, it is common knowledge to the clinical anesthesiolo-gist that regional anesthesia results in reduced blood loss aswell as a reduction in thromboembolic events postoperatively.This interesting study considered a posterior lumbar plexusblock since a significant portion of the hip is innervated viabranches of the lumbar plexus. A randomized, double-blindedtrial of 60 consecutive patients undergoing total hip arthro-plasty under general anesthesia was performed. Thirty patientshad general anesthesia alone and 30 patients had general anes-thesia with the lumbar plexus block. Pain scores and morphineconsumption postoperatively were evaluated over a 48-h pe-riod. Patients in the control group required supplemental nar-cotic (20/30) versus those in the lumbar plexus block group(6/30). No BIS monitor was employed simply with the endpoint of additional analgesic being an increase in blood pres-sure or heart rate greater than 130% of the baseline. Epidural-like distribution of anesthesia occurred in 3 of 28 patients receiv-ing the block. Incidence of nausea and vomiting was similar inboth groups and pain scores were significantly lower until the6-h period postoperatively. There was a block-associated re-duction in hemorrhage. These results are not surprising; how-ever, it would be unlikely that this block would be done in arepeated series and the authors describe a continuous catheter-based technique, which they have presented in abstract formfor longer-term postoperative pain relief. The associated com-plications with this block must be weighed with these positiveand predictable findings. The complexity of proper placementof this block compared with other regional techniques and itspotential side effects would make this block difficult to imple-ment in the operating room. The authors should be comple-mented for this study and great consideration for its potentialbenefits in clinical practice should be considered.

Anesthesia (10)

Scott S. Reuben, John P. Reuben:

Brachial plexus anesthesiawith verapamil and/or morphine. (Baystate Medical Center and theTufts University School of Medicine, Springfield, MA)

Anesth An-alg

2000;91:379–383.

This study examined the analgesic effects of administeringmorphine, verapamil, or its combination into the brachialplexus sheath with lidocaine in 75 patients undergoing upperextremity orthopedic surgery. All patients received brachialplexus anesthesia with 40 mL of 1.5% lidocaine and epineph-rine 5

m

g/mL. Patients were randomized to 1 of 5 groups:Group 1 received IV saline; Group 2 received IV verapamil2.5 mg and morphine 5 mg; Group 3 received IV verapamil2.5 mg and morphine 5 mg was added to the lidocaine solu-tion; Group 4 received IV morphine 5 mg and verapamil 2.5

mg was added to the lidocaine solution; and Group 5 receivedverapamil 2.5 mg and morphine 5 mg was added to thelidocaine solution. Postoperatively, patients rated their pain(0–10) at 1, 6, 12, and 24 h. Patients were instructed to take 1acetaminophen 325 mg/oxycodone 5 mg tablet every 3 hwhenever the pain score exceeded 3. Analgesic duration wassignificantly increased in those patients receiving brachialplexus blocks with morphine (Groups 3 and 5) (

P

,

0.005).The total 24 h acetaminophen/oxycodone was also less inGroups 3 and 5 (

P

,

0.03). Duration of anesthesia (time of ab-olition of pinprick response) was significantly increased inthose patients receiving brachial plexus blocks with verapamil(Groups 4 and 5) (

P

5

0.002). Conclude that the addition ofverapamil to the brachial plexus block with lidocaine can pro-long the duration of sensory anesthesia, but it had no effect onanalgesic duration of 24-h analgesic use.

Comment

by Alan David Kaye, MD, PhD.It is well established that calcium channel blockers potenti-

ate analgesic effects of both local anesthetics and opioids. Adesire for improvement of the quality and duration of brachialplexus blockade has led many investigators to study variousagents in addition to standard local anesthetics. This interest-ing double-blinded study involving 82 patients scheduled forelective upper extremity orthopedic surgery involved 5 groups.Interestingly, the combination of verapamil and morphine viathe brachial plexus did not provide any additional analgesic ef-fect, which is different than previous studies. The subjectivityof telephone data and the relatively small sample size in eacharm of this study make statistically significant findings harderto ascertain and relevant changes in clinical practice less con-vincing. Further, the authors do not appropriately note thecomplexity of calcium channel pharmacology and its overallrole in opioid as well as local anesthetic modulation. Futurestudies with more precise endpoints for efficacy and durationare warranted if clinical practice is to be altered and acceptedby the practitioner.

Anesthesia (11)

R.S. Simpson, P.E. Macintyre, D. Shaw, A. Norton, J.R. Mc-Cann, E.J. Tham:

Epidural catheter tip cultures: results of a4-year audit and implications for clinical practice. (Royal Ade-laide Hospital and University of Adelaide, Adelaide, Australia)

Reg Anesth Pain Med

2000;25:360–367.

This study aimed to evaluate the clinical relevance of routinemicrobiological culture of epidural catheter tips after use inacute pain management, and to identify patterns of culture re-sult with respect to both indications for, and duration of, epi-dural catheterization. Over a 4-year period, when acute painservice (APS) protocol required epidural catheter tips to besent for microbiological culture on removal, APS saw 1,810patients who had received epidural analgesia. The records ofthe patients were reviewed. Culture results were available for1,443 (79.7%) patients: 1,027 catheter tips (71.2%) were ster-ile, while 416 (28.8%) were positive for at least 1 type of mi-croorganism. Clinically, no epidural space infections were iden-

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tified. The highest positive culture rates were found fromepidural catheters used in treatment of pain from fracturedribs or fractured pelves. The lowest incidences occurred inelective orthopedic and thoracic surgery. The proportion ofepidural catheters with positive culture results steadily in-creased with the duration of catheterization, but there were noclinically significant differences for catheters left in situ for ei-ther 3 or 4 days. Conclude that a significant proportion of epi-dural catheter tips may be “culture positive” after removal. Itis suggested that this probably represents colonization of theskin at the catheter insertion site and subsequent contamina-tion of the catheter tip on removal of the catheter. The largenumber of “culture positive” tips in the absence of clinicallyidentifiable epidural space infection suggests that routine cul-ture of epidural catheter tips is clinically irrelevant in the vastmajority of cases, and that it is not a good predictor of thepresence of an epidural space infection.

Comment

by Alan David Kaye, MD, PhD.Clinically relevant epidural catheter-induced infection is

quite rare with the largest study on this topic revealing1⁄505,000 catheter placements. This retrospective study in-volved the insertion of 1810 epidural catheters. At the time ofinsertion, full aseptic precautions were employed. When thecatheters were removed, they were cultured and it was re-vealed that 28.8% were positive for at least 1 organism. Thisprevalence is relatively consistent with other published studies.The most common organism found was coagulase negativestaphylococcus. Interestingly, not one of these patients devel-oped an epidural abscess. The authors speculate that the rela-tively common prevalence of organism positive cultures wasrelated to poor sterile technique at the catheter insertion site atthe time of placement and/or removal. The authors concludethat epidural catheter contamination in the vast majority ofcases is clinically irrelevant. In as much as epidural abscess canhave vital clinical implications, it behooves the practitioner toadhere to strict sterile techniques even though the likelihood ofinfection is extremely low. Certainly, this study reinforces thefact that routine culture of epidural catheter tips is not a goodpredicator of epidural space infection.

Anesthesia (12)

Wendy B. Silverstein, Moin U. Saiyed, Anthony R. Brown:

Adeltoid motor response is a satisfactory endpoint for successfulblock. (Columbia Presbyterian Medical Center, New York,NY)

Reg Anesth Pain Med

2000;25:356–359.

This study investigates the notion that a deltoid twitch may bejust as effective as one in the biceps for predicting a successfulmotor block. Patients (N

5

160) scheduled for shoulder sur-gery were studied prospectively. Interscalene blocks (ISBs)were performed using neurostimulation according to our stan-dard technique. Twitches of the deltoid or biceps or both,whichever appeared first, were accepted and used as the end-point for needle placement and injection of local anesthetic.Motor block success, i.e., patient inability to lift the armagainst gravity, and minutes to motor block onset were re-

corded. Of the 160 ISBs performed, a biceps twitch was elic-ited in 61 patients. In 54 patients, a deltoid twitch was elicitedand in 45 patients, both a biceps and deltoid contraction wereelicited simultaneously. The failure rate did not differ widelyamong the groups; there was 1 failed motor block in the del-toid group and none in the other groups. There was no statisti-cally significant difference in onset times between the 3 muscletwitch groups. Conclude that a deltoid twitch is as effective asa biceps twitch in determining accurate needle placement forISB and in predicting successful motor block. Acceptance of adeltoid twitch during ISB eliminates the need for further prob-ing and may translate into better patient acceptance and in asmaller risk of needle-induced nerve damage.

Comment

by Alan David Kaye, MD, PhD.Interscalene brachial plexus block provides a valuable tech-

nique for shoulder surgery. The literature is in agreement withelicitation of paresthesias versus peripheral nerve stimulation.The literature is somewhat unclear regarding deltoid muscleversus biceps twitch as a satisfactory endpoint, prior to injec-tion of local anesthetic. This prospective study involved 160patients presenting for elective shoulder surgery. A bicepstwitch was elicited in 61 patients; 54 had a deltoid twitch, andin 45 patients, both a biceps and deltoid twitch were elicited.There was no statistically different onset time in the 3 groups;however, the failure rate did not differ in the 3 groups either(only 1 patient in the deltoid group had a failed block). Theauthors conclude that a deltoid twitch is as effective as one inthe biceps at ensuring a successful interscalene brachial plexusblock and that repositioning is not warranted if either musclegroup is elicited. The authors should be applauded for thisstudy because it strongly suggests that essentially any elicita-tion of deltoid or biceps twitch will result in a highly successfuland clinically useful block.

Anesthesia (13)

Miquel Angel Reina, Oscar A. De Leon, Andres Lopez, JoseDe Andres, Sara Martin, Miquel Mora:

An in vitro study ofdural lesions produced by 25-gauge Quincke and Whitacreneedles evaluated by scanning electron microscopy. (Hospitalde Mostoles, Madrid Spain)

Reg Anesth Pain Med

2000;25:393–402.

This study evaluated the dural lesions produced by Whitacreand Quincke spinal needles in the external and internal surfaceof the dura mater of the lower spine area in an attempt to gainmore insight into the pathophysiology of postdural punctureheadaches (PDPH). The T11-L4 dural membranes from 5fresh (immediately after extraction of organs for transplanta-tion) male patients declared brain dead, ages 23, 46, 48, 55,and 60, were excised by anterior laminectomy. Morphologicorientation of the membrane and normal pH were maintained;100 punctures at 90-degree angles were done with a new nee-dle each time, 50 with 25-gauge Whitacre and 50 with 25-gauge Quincke needles. Half of the punctures with theQuincke needles were done with the bevel in the parallel direc-tion to the axis of the spinal cord, and the rest with the bevel


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89

perpendicular to it. Fixation in solutions of 2.5% glutaralde-hyde phosphate buffer, followed by dehydration with acetone,was done 15 min after the punctures. The acetone was re-moved and the specimens were metallized with carbon fol-lowed by gold and inspected under a scanning electron micro-scope. When the area of the dural lesions found in the externaland internal surfaces produced by the 2 types of needles wascompared, no significant differences were found. The percent-age of lesion closing area with the Quincke needles was 88.3%and 82.7% in the external and internal surfaces, respectively.With the Whitacre needles, the percentage of closing was86.8% and 84.8% in the epidural and arachnoid surfaces, re-spectively. There were differences noted in the morphology ofthe lesions. The Whitacre needles produced coarse lesions withsignificant destruction in the dura’s fibers while the Quinckeneedles produced a “U”-shaped lesion (flap) that mimics theopened lid of a tin can, regardless of the tip’s direction. Con-clude that the needles produced lesions in the dura with differ-ent morphology and characteristics. Lesions with the Quinckeneedles resulted in a clean-cut opening in the dural membranewhile the Whitacre needle produced a more traumatic openingwith tearing and severe disruption of the collagen fibers. Thelower incidence of PDPH seen in the Whitacre needles may beexplained, in part, by the inflammatory reaction produced bythe tearing of the collagen fibers after dural penetration. Theinflammatory reaction may result in a significant edema,which may act as a plug limiting the leakage of the cerebrospi-nal fluid.

Comment

by Andrew D. Rosenberg, MD.This is an interesting article that explains why a patient will

develop a postdural puncture headache (PDPH) after receivinga spinal with a Quincke needle and not after a Whitacre-typeneedle. The explanation is based more upon an inflammatoryreaction than the direction of the needle cut. The Quinckeneedle appears to make a sharp cut while the Whitacre needleinduced an inflammatory response including edema, whichcould block off the dura from leaking. It is very interesting thatthe response seen after the Whitacre needle was utilized oc-curred as quickly as it did. The article introduces the questionas to whether a Quincke needle or a Whitacre needle is associ-ated with more trauma to the dura, and which is better for de-creasing the incidence of PDPD.

Anesthesia (14)

Salim M. Jahangir:

Tip-holed spinal needle: a new design con-cept. (Sir Salimullah Medical College and Mitford Hospital,Dhaka, Bangladesh)

Reg Anesth Pain Med

2000;25:403–407.

This article discussed new technology regarding the produc-tion of finer spinal needles and described a new spinal needletip design. Complications associated with dura-arachnoidpuncture for spinal anesthesia were taken into account. Post-dural puncture headache (PDPH) and needle bending arestated as being significant complications. Although pencil-point needles significantly reduce PDPH, it is stated that theseneedles also have their limitations such as obstruction of the

delivery port by tissues affecting both cerebrospinal fluid flashback and drug delivery. The problem of tip bending was alsoaddressed. At the center of the discussion was the newly de-signed spinal needle tip that was created to overcome the dis-advantages of other spinal needles. Analyzing the performanceof the existing needles, the conclusion was drawn that the cri-teria of an ideal spinal needle may be as follows: (1) the exter-nal diameter of the needle should be as thin as possible and thetip should be a dural fiber-spreading variety; (2) the shaft andtip should be capable of withstanding forces during needleplacement; and (3) it should also have a drug delivery hole thatdoes not weaken the needle or become obstructed by tissue.

Comment

by Andrew D. Rosenberg, MD.This article introduces a new type of needle for performing

spinal anesthesia techniques. According to the authors, classicQuincke-type needles are associated with postdural punctureheadache (PDPH), while side port blunt needles may be associ-ated with mechanical problems such as back flow or havingtissue obstruct side port. Therefore, the authors designed anew type of needle that is pencil point in shape, but the re-moval stylet is the component that forms the pencil point.When the stylet is removed, the needle has a conical distalshape with the opening at the end. The authors believe thatthis “new spreading beveled needle tip” will help alleviateproblems with PDPH as well as the problems associated withside port holes. While the idea is very intriguing, it remains tobe seen how successful the needle will be.

Anesthesia (15)

Yasuhisa Okunda, Keiko Okuda, Masayuki Shinohara, Toshi-mitsu Kitajima:

Use of computed tomography for maxillarynerve block in the treatment of trigeminal neuralgia. (DokkyoUniversity School of Medicine, Mibu, Tochigi, Japan)

RegAnesth Pain Med

2000;25:417–419.

A report of a 90-year-old woman who had a 30-year history ofepisodic pain in her right maxillary region is presented. An at-tempt to block the nerve with classic technique was made, buteliciting paresthesia could not identify the nerve. In addition,bleeding was noted after repeated attempts. To minimize com-plications and confirm the correct position of the needle tip,the block was planned with a suprazygomatic approach usingcomputed tomography (CT) guidance. The needle was in-serted without paresthesia. The CT scan showed the needle tipwas placed at the entrance of the pterygopalatine fossa and thedistribution of contrast medium spread appropriately aroundthe pterygopalatine fossa. After confirming the clinical effectand lack of complications of the block using the local anes-thetic, 0.5 mL of 7% phenol was injected. The technique re-sulted in complete sensory loss in the area innervated by themaxillary nerve and did so without complications.

Comment

by Andrew D. Rosenberg, MD.This is an interesting article in which the authors describe

their technique for treating trigeminal neuralgia. The authorswere faced with a significant problem, which was to perform a

90

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maxillary nerve block in a patient with difficult anatomy. Theapproach and technique were clearly thought out with an ex-cellent result. The axial cuts demonstrate needle position un-der CT scan and the appropriate spread of contrast materialthrough the pterygopalatine fossa.

Anesthesia (16)

Octavio Calvillo, Ioannis M. Skaribas, Carl Rockett:

Computedtomography—guided pudendal nerve block. A new diagnosticapproach to long-term anoperineal pain: a report of two cases.(Baylor College of Medicine, Houston, TX)

Reg Anesth PainMed

2000;25:420–423.

This report showed the value of computed tomography (CT)in selectively blocking the pudendal nerve in patients withlong-term anogenital pain of uncertain etiology. In 1 patient, acompetitive cyclist, blocking the nerve under CT substantiatedthe diagnosis of pudendal neuralgia. The procedure relievedthe pain for approximately 24 h. In the other patient, puden-dal nerve block produced perineal analgesia, but no pain relief.Superior hypogastric plexus block relieved the pain signifi-cantly for about 4 weeks on 2 separate occasions, suggestingsympathetically maintained pain. Conclude that the use of CTto guide the procedure allowed precision in performing theprocedure and in making a differential diagnosis.

Anesthesia (17)

Andrei Goldstein, Patrick Grimault, Aude Henique, MicheleKeller, Anne Fortin, Emile Darai:

Preventing postoperative painby local anesthetic instillation after laparoscopic gynecologicsurgery: a placebo-controlled comparison of bupivacaine andropivacaine. (Hotel-Dieu Hospital, Paris, France)

Anesth An-alg

2000;91:403–407.

This study tested the hypothesis that local anesthetics instilledat the end of laparoscopic gynecologic procedures are able toprevent postoperative pain at wake-up and during the first 24 h.A total of 180 patients were randomly assigned into three groupsto receive an intraperitoneal instillation of 20 mL of eitherbupivacaine 0.5% (Group B), ropivacaine 0.75% (Group R)or saline (Group S) at the end of surgery. All patients receivedanalgesia with acetaminophen and ketoprofen IV infusions. Painwas assessed by using a 0-10 graded numerical scale (NS) ev-ery 5 min in the postanesthesia care unit and IV morphine wasadministered if NS was

.

4. Assessment of pain continued ev-ery 4 h on the ward, and subcutaneous morphine was injectedif needed to keep the NS score

,

4. Postoperative nausea andvomiting (PONV) was rated on a 4-point scale. The morphineconsumption at wake-up and over the first 24 h was significantlylower (

P

,

0.05) in Group B (mean, 0.92 mg at wake-up; 3.08mg over 24 h) and in Group R (mean, 0.25 mg at wake-up;0.69 mg over 24 h), than in Group S (mean, 4.18 mg at wakeup; 12.93 mg over 24 h). The morphine-sparing effect of ropi-vacaine was significantly greater than that of bupivacaine. Bothlocal anesthetics were effective in the prevention of PONV.

Conclude that local anesthetics should be instilled in all gyne-cologic patients at the end of all laparoscopic procedures.

Anesthesia (18)

Andrea Casati, Luca Magistris, Guido Fanelli et al:

Small-doseclonidine prolongs postoperative analgesia after sciatic-femo-ral nerve block with 0.75% ropivacaine for foot surgery. (Uni-versity of Milan, Milan, Italy)

Anesth Analg

2000;91:388–392.

This study evaluated the effects of adding small-dose clonidineto 0.75% ropivacaine during peripheral nerve blocks, 30 ASAphysical status I and II patients undergoing hallux valgus re-pair under combined sciatic-femoral nerve block were ran-domly allocated in a double-blinded fashion to receive blockplacement with 30 mL of either 0.75% ropivacaine alone(Group Ropivacaine, n

5

15) or 0.75% ropivacaine plus

m

g/kgclonidine (Group Ropivacaine-Clonidine, n 5 15). Hemody-namic variables, oxygen saturation, and levels of sedation, aswell as the time required to achieve surgical block and time tofirst analgesic request, were recorded by a blinded observer.Time to surgical blockade required 10 min in both groups. Pa-tients in the Ropivacaine-Clonidine Group were more sedatedthan patients in the Ropivacaine Group only 10 min afterblock placement. No differences in oxygen saturation and he-modynamic variables, degree of pain measurement at firstanalgesic request, and consumption of postoperative analge-sics were observed between the two groups. The mean timefrom block placement to first request for pain medication wasshorter in Group Ropivacaine (13.7 h; 25th–75th percentiles:11.8–14.5 h) than in Group Ropivacaine-Clonidine (16.8;25th–75th percentiles: 13.5–17.8 h) (P 5 0.038). Concludethat adding 1 mg/kg clonidine to 0.75% ropivacaine provideda 3-h delay in first request for pain medication after hallus val-gus repair, with no clinically relevant side effects.

Anesthesia (19)

Richard A. Steinbrook, Mercedes A. Concepcion: Respiratorygas exchange and hemodynamics during lumbar epidural an-esthesia: effects of lidocaine with and without epinephrine.(New England Medical Center, Tufts University School of Med-icine, Boston, MA) Reg Anesth Pain Med 2000;25:380–384.

In this study, 12 healthy patients (age, 22 to 46 years) under-going surgery on the knee were randomly assigned to receiveeither 2% lidocaine (Group L) or 2% lidocaine with epineph-rine 5 mg ? mL21 (Group E), approximately 20 mL, over 10 minvia lumbar epidural catheter. Total-body oxygen consumption(VO2) and carbon dioxide production (VCO2) were deter-mined by indirect calorimetry; hemodynamic measurementswere obtained by noninvasive thoracic electrical bioimped-ance. Values of VO2, VCO2, heart rate (HR), cardiac index(CI), and mean arterial blood pressure (MAP) were determinedevery minute and averaged every 5 min for 30 min. Compari-sons were made with analysis of variance (ANOVA) (withingroups) and t-tests (between groups). Differences were consid-

Multidisciplinary Abstracts • 91

ered significantly different if P , 0.05. VO2 did not change ineither group, while VCO2 increased significantly by 22% at 20min in Group E. Increases in HR were apparent in bothgroups, with significantly greater increases in Group E. CI didnot change in Group L, but increased by 41% in Group E.MAP decreased significantly by 11% in Group E, but did notchange in Group L. Conclude that the addition of epinephrine,5 mg ? mL21, to the epidural injection of 2% lidocaine is asso-ciated with changes not only in hemodynamics, but also in res-piratory gas exchange.

Anesthesia (20)

Guido Schuepfer, Christoph Konrad, Joachim Schmeck, GertPoortmans, Bruno Staffelbach, Martin Jöhr: Generating a learn-ing curve for pediatric caudal epidural blocks: an empiricalevaluation of technical skills in novice and experienced anes-thetists. (Institute of Anesthesiology, Lucerne, Switzerland)Reg Anesth Pain Med 2000;25:385–388.

The aim of this study was to assess the number of caudalblocks needed to guarantee a high success rate in performingcaudal epidural analgesia in children. The technical skills of 7residents in anesthesiology who performed caudal blocks wereevaluated during 4 months using a standardized self-evalua-tion questionnaire. At the start of the study period, the resi-dents had no prior experience in pediatric anesthesia or in per-forming caudal epidural blocks. All residents entered thepediatric rotation after a minimum of 1 year of training inadult general and regional anesthesia. The blocks were ratedusing a binary score. For comparison, the success rates of 8 ex-perienced staff anesthesiologists were collected during thesame period using the same self-evaluation questionnaire. Sta-tistical analyses were performed by generating individual andinstitutional learning curves using the pooled data. The learn-ing curves were calculated with the aid of a least-square fitmodel and 95% confidence intervals were estimated by aMonte-Carlo procedure with a bootstrap technique. The suc-cess rate of residents was 80% after 32 procedures (95% con-fidence interval of 0.59 to 1.00). The pooled success rate of thestaff anesthesiologists was 0.73 (mean) with a standard devia-tion of 0.45, which was not statistically different from the suc-cess rate of the residents. Conclude that high success rates inperforming caudal anesthesia in pediatric patients can be ac-quired after a limited number of cases. Success rates of resi-dents learning this procedure are comparable to the results ofthe staff anesthesiologists.

Basic Science (21)

Tamie Takenami, Saburo Yagishita, Fumio Asato, SumioHoka: Neurotoxicity of intrathecally administered tetracainecommences at posterior roots near entry into the spinal cord.(Kitasato University, Kanagawa, Japan) Reg Anesth Pain Med2000;25:372–379.

This study examined the histopathologic effects of intrathe-cally administered tetracaine. Sixty Wistar rats randomly re-

ceived either 20%, 10%, 5%, 3%, 1%, 0.5%, or 0% tetra-caine dissolved in 10% glucose solution or no solution via achronically implanted intrathecal catheter. The spinal cord atL1, posterior and anterior roots and cauda equina were ex-cised 5 days later, sectioned, processed, and prepared for lightand electron microscopic examinations. Rats treated with tet-racaine at 10% or 20% developed lesions in the posteriorwhite matter and posterior roots. Rats injected with 3% or5% tetracaine developed lesions, which began in the posteriorroots close to the spinal cord and extended to the posteriorwhite matter. The lesions were characterized by axonal degen-eration. Injections of <1% of tetracaine did not cause anypathological changes. The results suggest that the initial targetof intrathecal tetracaine neurotoxicity may be the posteriorroots at their entry into the spinal cord, where the axons aredevoid of myelin sheath and thus represent a sensitive area forneurotoxic change.

Comment by James E. Heavner, DVM, PhD.The reassuring aspect of this study is that no significant le-

sions were found when rats were given clinically used concen-trations of tetracaine. The investigators do make a case thatclinically used concentrations of tetracaine might be neuro-toxic in humans based on the observation that the duration ofaction of tetracaine is shorter in rats than in humans. The dis-tribution of the lesions is curious in that 10% tetracaine pro-duced lesions in the posterior rootlets and in the posteriorrootlet entry zone, but did not produce lesions in the fasciculusgracilis. The implication is that rootlets posterior to lamina L1(the L1 segment that was examined) that were destroyed donot project into the fasciculus gracilis. One would expect thatdestruction of lamina L2 posterior rootlets that projected intothe fasciculus gracilis would produce lesions visible at the EMlevel at L1 5 days after damage. The absence of lesions in theL1 fasciculus gracilis puzzles me. I am also puzzled by the sug-gestion that all posterior rootlets loose their myelin sheath justbefore entry into the posterior white matter of the spinal cord(Obersteiner-Redlich zone). To my knowledge, most posteriorrootlets do not have this nonmyelinated zone and; therefore,the absence of the myelin would make only a portion of theposterior rootlets vulnerable to tetracaine neurotoxicity assuggested by the authors. In short, there are some anatomicalrelationships that do not fit with the distribution of lesions de-scribed by the investigators.

Basic Science (22)

Tomoki Nishiyama, Rodney J.Y. Ho, Danny D. Shen, Tony L.Yaksh: The effects of intrathecal morphine encapsulated inl- and d-dipalmitoylphosphatidyl choline liposomes on acutenociception in rats. (University of California, San Diego, CA)Anesth Analg 2000;91:423–428.

This study evaluated the antinociceptive effects of morphineencapsulated in liposomes of two isomeric phospholipids,l-dipalmitoylphosphatidyl choline (l-DPPC) and d-dipalmi-toylphosphatidyl choline (d-DPPC), in comparison with mor-phine in saline. Sprague-Dawley rats with chronic lumbar in-

92 • multidisciplinary abstracts

trathecal catheters were tested for their acute nociceptiveresponse using a hindpaw thermal escape test. Their generalbehavior, motor function, pinna reflex, and corneal reflexwere also examined. The duration of antinociception waslonger in both liposomal morphine groups than in the freemorphine group. The peak antinociceptive effects were ob-served within 30 min after intrathecal morphine, l-DPPC ord-DPPC morphine injection. The rank order of the area underthe effect-time curve for antinociception was l-DPPC mor-phine . d-DPPC morphine . morphine. The 50% effective dosewas: 2.7 mg (morphine), 4.6 mg (l-DPPC morphine), and 6.4 mg(d-DPPC morphine). d-DPPC morphine had fewer side effectsfor a given antinociceptive AUC than morphine. Conclude thatl-DPPC and d-DPPC liposome encapsulation of morphine pro-longed the antinociceptive effect on acute thermal stimulationand could decrease side effects compared with morphine alone.

Comments by James E. Heavner, DVM, PhD.One would intuitively expect that encapsulation of a drug

would prolong its duration of action and reduce systemic sideeffects. However, the results of this study taken in the contextof studies with the encapsulation of other opioids indicate thatthe physical/chemical properties of the opioid can have an im-portant influence on the results of encapsulation. For example,the investigators have demonstrated that encapsulation of al-fentanyl had only a modest effect on its duration of action, pre-sumably because of the ability of the lipophilic alfentanyl torapidly defuse through the membranes of the liposomes. Onequestion the study leaves open is whether or not the material usedfor encapsulation has consistent effects on its own. The investi-gators previously found that intrathecal delivery of l-dipalmi-toylphosphatidyl choline resulted in a steroid-sensitive allodynia.However, in the present study the investigators did not observethis. Thus, there is much to be learned about the science andart of drug encapsulation for therapeutic purposes in humans.

Basic Science (23)

Igor Kissin, Cheryl A. Bright, Edwin L. Bradley, Jr.: Acute tol-erance to continuously infused alfentanil: the role of cholecysto-kinin and N-methyl-D-aspartate-nitric oxide systems. (Brighamand Women’s Hospital, Boston, MA) Anesth Analg 2000;91:110–119.

To test the role of cholecystokinin (CCK) and N-methyl-D-aspartate-nitric oxide (NMDA-NO) systems in the develop-ment of acute tolerance to analgesia during alfentanil IV in-fusion, experiments were conducted in rats with the use of aninfusion algorithm designed to maintain a constant plasma levelof the opioid for 4 h. The degree of acute tolerance was deter-mined on the basis of decline in the level of analgesia measuredwith a tail compression test. CCKB receptor antagonists (pro-glumide, CI-988, and L-365,260) and NMDA-NO cascade in-hibitors (dizocilpine and NO synthase inhibitor) were admin-istered before the start of alfentanil infusion. Use of 30 mg/kgproglumide, 10 mg/kg CI-988, and 1 mg/kg L-365,260 attenu-ated acute tolerance at 1 h of alfentanil infusion by approxi-mately 60%, 55%, and 70%, respectively, and by the end ofthe 4-h infusion by 50%, 50%, and 25%, respectively. Use of

0.1 mg/kg dizocilpine and 10 mg/kg NG-nitro-L-arginine me-thyl ester attenuated acute tolerance at 1 h of alfentanil infu-sion by approximately 65% and 65% and by the end of the4-h infusion by 30% and 0%, respectively. Comparison of theresults with CCKB receptor antagonists and inhibitors of NMDA-NO cascade demonstrates that both groups provide more or lesssimilar degrees of attenuation of acute tolerance to the antinoci-ceptive effect of alfentanil, and none of these drugs completely pre-vents tolerance development.

Basic Science (24)

Xinhui Li, Zhihong Zhao, Hui-Lin Pan, James C. Eisenach,Xavier Paqueron: Norepinephrine release from spinal synap-tosomes. (Wake Forest University School of Medicine, Win-ston-Salem, NC) Anesthesiology 2000;93:164–172.

The purpose of this study was to determine if clonidine couldinhibit release of NE in a preparation of spinal cord tissuelacking synaptic circuits. Crude synaptosomes were preparedfrom male Sprague-Dawley rat spinal cord, loaded with[3H]NE, and stimulated by potassium chloride to release[3H]NE. Samples were incubated with clonidine in the absenceor presence of various inhibitors. To study the effect of a2A-adrenergic receptor subtypes, some animals were pretreatedwith an oligodeoxynucleotide (ODN) composed of a sense orantisense sequence to a portion of this receptor. Potassiumchloride produced a concentration-dependent increase in[3H]NE release, and this release was inhibited by clonidinewith a concentration producing 50% maximal inhibition(IC50) of 1.3 mm. The effect of clonidine was inhibited by thea2A-adrenergic antagonists, yohimbine, and idazoxan, but notby a1A-adrenergic, muscarinic, or opioid antagonists. Intra-thecal pretreatment with antisense ODN to a2A-adrenergic re-ceptors reduced a2A-adrenergic receptor protein expressioncompared with sense ODN control and also reduced cloni-dine-induced inhibition of [3H]NE release. Conclude thatthese data demonstrate the existence of classic autoinhibitorya2A-adrenergic receptors in the spinal cord, probably of thea2A subtype. They further suggest that clonidine-induced stim-ulation of spinal NE release must occur from indirect actions,presumably due to activation of a spinal circuit.

Basic Science (25)

Jean-Pierre Estebe, Pascal Le Corre, François Chevanne, GuyCathelineau, Roger Le Verge, Claude Ecoffey: Motor blockadeby brachial plexus block in the sheep. (Université de Rennes,Rennes, France) Anesthesiology 2000;93:292–294.

This report aimed to evaluate the approach of the brachialplexus block in a sheep model using bupivacaine. Blocks wereperformed with electrical stimulation using a 50mm insulatedneedle. When muscle twitches were elicited with 0.5-mA im-pulses, drug solutions were injected over a 1-min period. Nervestimulation and injection of methylene blue were performed intwo sheep that were killed 2 h later for postmortem anatomiccontrol of setting injection. Twenty-three nerve stimulations


were achieved; the brachial plexus was reached in less than 5min and within 5-cm depth (range, 1.5–4.5 cm). Sheep cadaverdissection showed no visible vital structure in close proximityto the site of injection. Dissection records confirmed that thebrachial plexus anatomy of sheep was close to that of humans.An optimal distribution of contrast medium was obtainedwith 30-mL volume. Usually 1–2 min was sufficient to recoverfrom anesthesia and to allow motor evaluation. No apparentsign of cardiac or central nervous system toxicities were re-corded with any dose (0.5–4.3 mg/kg). All animals demon-strated a complete recovery, and no sequelae were recorded.Conclude that the brachial plexus block was performed easilyin sheep and produced a motor block that varied in a dose-related fashion. This model may be useful for assessing re-gional anesthesia of new drugs and/or new drug delivery.

Comment by James E. Heavner, DVM, PhD.Two questions ran through my mind as I read this manu-

script. One, is there a need for an animal model for brachialplexus block, the other, is the sheep the model of choice? Theinvestigators state that “laboratory animal studies are neces-sary models for the assessment of new drugs and/or drug deliv-ery systems used in regional anesthesia.” They indicate thatwith the exception of sciatic nerve block in rats, there are fewdata in the literature. This does not directly answer the ques-tion of whether or not there is a need for an animal model forbrachial plexus block evaluation. To be positive, assume thereis a need and then move to the question of whether or not thesheep would be the appropriate model. The investigators de-scribe variations between the sheep and humans with respectof the origin of the brachial plexus and the phrenic nerves.What is not stated is that the gross anatomical morphology ofhumans and sheep are quite different, which may or may notbe significant. Again to be positive, assume that the differenceis not significant. If we accept that there is a need for an animalmodel and that the sheep is a suitable model, then we must askwhat is it we want to do with the model? It would have beenhelpful if the investigators provided some suggestions for fu-ture studies. While recognizing the importance of animal mod-els in advancing the science and art of regional anesthesia, I be-lieve there is limited need for an animal model to evaluate brachialplexus block and have reservation regarding the utility of sheep asa model for such studies. I believe that most inquiries regardingbrachial plexus block can be conducted safely on humans.

Basic Science (26)

Alla B. Khodorova, Gary R. Strichartz: The addition of diluteepinephrine produces equieffectivenes of bupivacaine enanti-omers for cutaneous analgesia in the rat. (Brigham and Women’sHospital, Boston, MA) Anesth Analg 2000;91:410–416.

This study investigated the effectiveness for cutaneous analge-sia of bupivacaine (Bup) stereoisomers in male rats. As a modelof infiltration anesthesia, inhibition of a nocifensive reflex bysubcutaneous injection of 0.6mL of different concentrations ofR-, S-, and racemic-Bup was evaluated quantitatively by thefraction of times a pinprick failed to evoke a nocifensive motor

response. R-Bup was more potent in the extent of the block;however, S-Bup had a longer-lasting action at smaller doses.This significant difference was apparent when R-Bup andS-Bup were administered in equipotent doses of 0.06% and0.075%, respectively. Co-injection of epinephrine (Epi) withthese equipotent doses enhanced and prolonged the blockingeffects of both Bup stereoisomers, although the dilutions of1:100,000 to 1:1,000,000 Epi itself induced partial, transientanalgesia. At 1:2,000,000 dilution, Epi alone had no analgesiceffect; however, when co-injected with the shorter-actingR-Bup (0.06%), Epi prolonged its blocking effect to equal theduration of the block evoked by equipotent S-Bup (0.075%).Conclude that R-Bup is more potent for cutaneous analgesiaand that the longer duration of the block by S-Bup probablyoriginates from vasoconstrictor activity.

Basic Science (27)

Mei Xu, Vesa K. Kontinen, Eija Kalso: Effects of radolmidine,a novel a2-adrenergicagonist compared with dexmedetomidinein different pain models in the rat. (University of Helsinki, Hel-sinki, Finland) Anesthesiology 2000;93:473–481.

This study determined the antinociceptive and sedative effectsof radolmidine in different models of acute and chronic pain.Dexmedetomidine and saline served as controls. Male Sprague-Dawley rats were studied in acute pain (tail flick), carrageenaninflammation, and the spinal nerve ligation model of neuro-pathic pain. Mechanical allodynia was assessed with von Freyfilaments, cold allodynia with the acetone test, and thermalhyperalgesia with the paw flick test. Locomotor activity-vigi-lance was assessed in a dark field. Dexmedetomidine and rad-olmidine were administered intrathecally in doses of 0.25 mg,2.5 mg, and 10 mg. In the tail flick test, radolmidine showed adose-dependent antinociceptive effect, being equipotent com-pared with dexmedetomidine. In carrageenan inflammation,intrathecal doses of 2.5 mg or 5 mg of dexmedetomidine/radol-midine produced significant antinociception compared withsaline (P , 0.01). The two drugs were equianalgesic. In theneuropathic pain model, an intrathecal dose of 5 mg dex-medetomidine-radolmidine had a significant antiallodynic effectcompared with saline (P , 0.01). The 2 drugs were equipotent. In-trathecal administration of both dexmedetomidine and radolmi-dine dose dependently decreased spontaneous locomotor activity-vigilance, but this effect was significantly smaller after intrathecaladministration of radolmidine than after intrathecal dexmedeto-midine. Conclude radolmidine and dexmedetomidine had equipo-tent antinociceptive effects in all tests studied. However, radolmi-dine caused significantly less sedation than dexmedetomidine,probably because of a different pharmacokinetic profile.

Basic Science (28)

Tomoyuki Kawamata, Keiichi Omote, Hajime Sonoda, MikitoKawamata, Akiyoshi Namiki: Analgesic mechanisms of ketaminein the presence and absence of peripheral. (Sapporo Medical Uni-versity School of Medicine, Sapporo, Japan) Anesthesiology 2000;93:520–528.


In this study, the authors investigated the contribution of thesupraspinal monoaminergic descending inhibitory system toketamine analgesia for acute nociception and inflammation-induced hyperalgesia. Male Sprague-Dawley rats were used.The paw withdrawal latencies to radiant heat stimuli weremeasured to assess the thermal nociceptive threshold. The an-algesic effects of intrathecal or intraperitoneal ketamine wereexamined in the rats that received unilateral intraplantar car-rageenan and in those that were untreated. In addition, it wasexamined whether pretreatment with intrathecal yohimbine ormethysergide inhibited the analgesic effects of ketamine. Us-ing an intrathecal microdialysis method, noradrenaline and5-hydroxytryptamine concentrations in lumbar cerebrospinalfluid were measured after intraperitoneal ketamine in both sa-line- and carrageenan-treated rats. In the untreated rats, intra-peritoneal but not intrathecal ketamine produced antinocicep-tive effects in a dose-dependent manner. Pretreatment withintrathecal yohimbine or methysergide inhibited these anti-nociceptive effects. Intraplantar carrageenan significantly re-duced paw withdrawal latencies on the injected paw, but noton the contralateral paw. Both intraperitoneal and intrathecalketamine reversed the shortened paw withdrawal latencies onthe injected side in a dose-dependent manner without any ef-fects on the contralateral side. Neither yohimbine nor methy-sergide inhibited these antihyperalgesic effects. In analyses ofmonoamines, the magnitiute of increase in monoamines afterintraperitoneal ketamine was significantly smaller in the carra-geenan-treated rats than in the saline-treated rats. Concludethat these results demonstrated that ketamine produced anti-nociceptive effects through an activation of the monoaminer-gic descending inhibitory system, whereas, in a unilateral periph-eral inflammation-induced hyperalgesic state, the monoaminergicsystem did not contribute to the antihyperalgesic effects of ket-amine. The mechanisms of the antinociceptive and antihyperalge-sic properties of ketamine are different.

Basic Science (29)

Esther M. Pogatzki, Peter K. Zahn, Timothy J. Brennan: Effect ofpretreatment with intrathecal excitatory amino acid receptorantagonists on the development of pain behavior caused byplantar incision. (University of Iowa, Iowa City, Iowa) Anes-thesiology 2000;93:489–496.

This study examined the role of N-methyl-D-aspartate(NMDA), non-NMDA, and metabotropic glutamate receptors(MGluRs) on the development of pain behavior after plantarincision. Rats with lumbar intrathecal catheters were anesthe-tized with halothane. Fifteen minutes before an incision wasmade, drug [40 nmol MK-801; 20 nmol NBQX; or 200 nmol[(1)-MCPG] or vehicle was injected intrathecally followed byan infusion of the same drug for 75 min. Withdrawal thresh-olds to calibrated von Frey filaments applied adjacent to thewound and response frequencies to a blunt mechanical stimu-lus applied directly to the wound were measured before inci-sion and 1, 2, 4, and 6 h after incision and then once daily for6 days. Preincision treatments with antagonists against theNMDA (MK-801) and Group I and II metabotropic receptors

[(1)-MCPG] did not inhibit the development of mechanicalhyperalgesia caused by incision. Preincision treatment with thenon-NMDA receptor antagonist NBQX increased withdrawalthresholds at 1 and 2 h and on postoperative day 1 comparedwith the vehicle group; response frequencies were reduced 1and 2 h after incision and on postoperative day 2 (P , 0.05).In an additional group, postincision treatment with NBQXwas similar to preincision treatment. Conclude spinal NMDAand MGluR antagonists may not be useful for preventing post-surgical pain. Spinal non-NMDA receptor antagonists reducedpain behaviors, but a preventive effect using preincision treat-ment was not apparent.

Comment by James E. Heavner, DVM, PhD.The incisional model using rats was developed by Dr. Bren-

nan and colleagues for the study of acute surgical pain. In aprevious study, they showed that blockade of non-NMDA ex-citatory amino acid receptors, but not blockade of NMDA re-ceptors nor mGluR receptors reduces postincisional pain if ad-ministered after the incision is made. This study shows thesame is true if the receptor antagonists are administered beforethe incision is made. However, the effect is not particularlymarked and; therefore, pursuit of non-MNDA excitatoryamino transmitter receptor blockers for the prevention ofpostincisional pain would not likely be fruitful. The results ofthe study do require us to rethink how postincisional pain dif-fers from other experimental pains and the phenomena of“wind-up” attributed to activation of the NMDA receptor.Worth keeping in mind is that incisional pain does not equalsurgical pain, which may involve traumatic injury to nervesand produce a neuropath pain, which strongly indicates in-volvement of NMDA receptors.

Basic Science (30)

H.-J. Häbler, S. Eschenfelder, X.-G. Liu, W. Jänig: Sympathetic-sensory coupling after L5 spinal nerve lesion in the rat andits relation to changes in dorsal root ganglion blood flow.(Christian-Albrechts-Universität, Kiel, Germany) Pain 2000;87:335–345.

In rats 3-56 days after L5 spinal nerve lesion, the authors ofthis study tested the responses of axotomized afferent fibers re-corded in the dorsal root of the lesioned segment to norepi-nephrine (NE, 0.5 mg/kg) injected intravenously and to selec-tive electrical stimulation of the lumbar sympathetic trunk(LST). In some experiments, blood flow was measured in thedorsal root ganglion (DRG) by laser Doppler flowmetry. Themajority of lesioned afferent fibers with spontaneous ac-tivity responded to neither LST stimulation (82.4%) nor NE(71.4%). In those that did react to LST stimulation, responsesoccurred only at high stimulation frequencies and they couldbe mimicked by nonadrenergic vasoconstrictor drugs (angio-tensin II, vasopressin). Excitatory responses to LST stimula-tion were closely correlated with the stimulation-induced pha-sic vasoconstrictions in the DRG. Therefore, the activation oflesioned afferents might be brought about indirectly by an im-paired blood supply to the DRG. To test this hypothesis, astrong and sustained baseline vasoconstriction in the DRG


was induced by blocking endothelial nitric oxide synthesiswith NG-nitro-L-arginine methyl ester (L-NAME) applied sys-temically. L-NAME enhanced baseline vascular resistance inthe DRG about threefold and also increased stimulation-induced vasoconstrictions. After L-NAME, the majority of ax-otomized neurons with spontaneous activity were activated byLST stimulation (76%) or NE (75%). Again, activationsclosely followed stimulation-induced phasic vasoconstrictionsin the DRG provided that a critical level of vasoconstrictionwas exceeded. Inhibitory responses to LST stimulation weregenerally rare and could be reversed to activation by pro-longed stimulation or after L-NAME. These results show thatsympathetic-sensory coupling occurs only in a minority of ax-otomized afferents after L5 spinal nerve injury. Like previousstudies, they cast doubt on the notion that L5 spinal nerve le-sion is a good model for sympathetically maintained pain.Since responses of lesioned afferent neurons to LST stimula-tion and NE could be provoked with high reliability after induc-ing vasoconstriction in the DRG, and since they mirrored stimu-lation-induced vasoconstrictions in the DRG, it appears that inthis model the association of sympathetic activity with afferentdischarge occurs mainly when perfusion of the DRG is impaired.

Comments by Marshall Devor, PhD.Animal research has revealed that massive ectopic afferent

discharge is generated in the dorsal root ganglion (DRG) fol-lowing nerve injury. This source of ectopic firing is in additionto activity that may be generated at the nerve injury site (Tinelsign). The combined impulse barrage is almost certainly an im-portant cause of neuropathic pain. It has been discovered re-cently that the intensity of the ectopic DRG barrage is modu-lated by sympathetic efferent activity. This is a potential linkbetween sympathetic activity and symptomatology in sympa-thetic related pain conditions such as complex regional painsyndrome/reflex sympathetic dystrophy. But what is the mech-anism of the sympathetic-sensory coupling? Considerable evi-dence indicates that axotomized DRG neurons become abnor-mally adrenosensitivity. Habler et al now point out an additional,indirect, coupling mechanism . . . modulation of intrinsic DRGblood flow. That is, sympathetic activity may reduce DRG bloodflow inducing partial ischemia, with the ischemia causing neu-ral excitation. This finding may also have broader implicationsas spinal pathology can also compromise DRG blood flow.Might low back pain and sciatica, for example, derive fromthis same process? It is surprising that ectopic firing in theDRG has played so little part in clinical thinking and practicein patients with neuropathic pain. So far.

Basic Science (31)

Timothy J. Boucher, Kenji Okuse, David L.H. Bennett, JohnB. Munson, John N. Wood, Stephen B. McMahon: Potent an-algesic effects of GDNF in neuropathic pain states. (King’sCollege London, London, United Kingdom) Science 2000;290:124–127.

Neuropathic pain arises as a debilitating consequence of nerveinjury. The etiology of such pain is poorly understood, and ex-

isting treatment is largely ineffective. We demonstrate herethat glial cell line-derived neurotrophic factor (GDNF) bothprevented and reversed sensory abnormalities that developedin neuropathic pain models, without affecting pain-related be-havior in normal animals. GDNF reduces ectopic dischargeswithin sensory neurons after nerve injury. This may arise as aconsequence of the reversal by GDNF of the injury-inducedplasticity of several sodium channel subunits. Together thesefindings provide a rational basis for the use of GDNF as a ther-apeutic treatment for neuropathic pain states.

Comment by Marshall Devor, PhD.Nerve injury frequently causes sensory neurons to become

electrically hyperexcitable. The resulting ectopic afferent firingis thought to be the immediate cause of ongoing pain, move-ment-evoked pain, and allodynia in neuropathic pain states.But why do the neurons become hyperexcitable? A popularhypothesis has it that when the axon is cut, the sensory cellbody in the dorsal root ganglion (DRG) is starved of essentialneurotrophic molecules that are normally produced in the pe-riphery and transported to the DRG via axoplasmic transport.If so, then providing an exogenous source of the critical neu-rotrophin should prevent, or even reverse, the hyperexcitabil-ity and the pain. Boucher et al tried this, administering 1 of 3candidate neurotrophins (NGF, NT-3, or GDNF) by the in-trathecal (i.t.) route. One of them, GDNF, worked dramati-cally. The authors believe that i.t. GDNF acts by diffusing intothe DRG (rather than the spinal cord) where it alters the ex-pression of the channel proteins that are responsible for elec-trical hyperexcitability.

Basic Science (32)

A. Oprée, M. Kress: Involvement of the proinflammatory cy-tokines tumor necrosis factor-alpha, IL-1 beta, and IL-6 butnot IL-8 in the development of heat hyperalgesia: effects onheat-evoked calcitonin gene-related peptide release from rat.(Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlan-gen, Germany) J Neurosci 2000;20:6289–6293.

In this study, the rat skin model was used to investigate the ef-fects of proinflammatory cytokines on the basal and heat-evoked release of calcitonin gene-related peptide (CCRP) fromnociceptors in vivo. In contrast to the excitatory effects of cy-tokines observed in vivo, none of the cytokines tested evokedany CCRP release at normal skin temperature of 328C. How-ever, the cytokines IL-1b, tumor necrosis factor (TNF)-a, andIL-6 but not IL-8 induced a pronounced and transient sensiti-zation of the heat-evoked CGRP release from nociceptors invitro. This heat sensitization was dose dependent, with EC50for IL-1b of 2.7 ng/mL and for TNF-a of 3.1 ng/mL. The max-imum IL-1b effect reached almost 600% of the heat-evokedrelease, and the maximum TNF-a effect induced a rise inCGRP release of 350%. In contrast to IL-1b and TNF-a, IL-6did not induce heat sensitization when applied alone, but wasonly effective in the presence of soluble IL-6 receptor. Thissuggests a constitutive expression of signaling receptors forTNF and IL-1b and the signal transduction molecule gp 130,


but not IL-6 receptor or IL-8 receptor. Furthermore, the acutecytokine signaling observed was independent of transcrip-tional pathways because sensitization occurred on short la-tency in vitro and under conditions that excluded chemotacticaccumulation of immune cells from blood vessels. Concludethat interleukins may play an important role in the initiationof heat hyperalgesia in inflammation and neuropathy.

Comment by Marshall Devor, PhD.Impulses in nociceptive afferents signal pain to a conscious

brain, but in addition, they have an efferent, effector role inperipheral tissue. Specifically, impulses arriving at a sensoryending may cause the release of various peptides and other po-tential inflammatory mediators, affecting local tissue circula-tion and the trophic state of the tissue. Oprée and Kress showthat specific cytokines can facilitate this release by loweringthe temperature required to evoke release of the calcitoningene-related peptide. If the temperature required were loweredto basal tissue temperature, a real possibility, then the peptideswould be released on a tonic basis at normal body tempera-ture. This could be a mechanism for the disruption of normaltissue integrity in chronic inflammatory conditions such asrheumatoid arthritis.

Basic Science (33)

Jun-Ming Zhang, Huiqing Li, Sorin J. Brull: Perfusion of themechanically compressed lumbar ganglion with lidocaine re-duces mechanical hyperalgesia and allodynia in the rat. (Uni-versity of Arkansas for Medical Sciences, Little Rock, AR) JNeurophysiol 2000;84:798–805.

This study used an animal model of lumbar radiculopathy toinvestigate the neurological mechanisms of cutaneous hyperal-gesia and tactile allodynia. The rat L5 dorsal root ganglion(DRG) was chronically compressed by inserting a hollow per-forated rod into the intervertebral foramen. The DRG wasconstantly perfused through the hollow rod with eitherlidocaine or normal saline delivered by a subcutaneous os-motic pump. Behavioral evidence for neuropathic pain afterDRG compression involved measuring the incidence of hind-limb withdrawals to both punctate indentations of the hindpaw with mechanical probes exerting different bending forcesand to light stroking of the hind paw with a cotton wisp. Be-havioral results showed that for saline-treated control rats: thewithdrawal thresholds for the ipsilateral and contralateralpaws to mechanical stimuli decreased significantly after sur-gery and the incidence of foot withdrawal to light stroking sig-nificantly increased on both ipsilateral and contralateral hindpaws. Local perfusion of the compressed DRG with 2%lidocaine for 7 days at a low flow-rate (1 ml/h), or for 1 day ata high flow-rate (8 ml/h) partially reduced the decrease in thewithdrawal thresholds on the ipsilateral foot, but did not af-fect the contralateral foot. The incidence of foot withdrawal inresponse to light stroking with a cotton wisp decreased signifi-cantly on the ipsilateral foot and was completely abolished onthe contralateral foot in the lidocaine treatment groups. Con-clude that compression of the L5 DRG induced central pain

syndrome that included bilateral mechanical hyperalgesia andtactile allodynia. Results also suggest that a lidocaine block, ora reduction in abnormal activity from the compressed gangliato the spinal cord, could partially reduce mechanical hyperal-gesia and tactile allodynia.

Comments by Marshall Devor, PhD.Tonic compression of the dorsal root ganglion (DRG) in

animal preparations, and presumably also in man, causes sen-sory cells to become electrically hyperexcitable. The resultingspontaneous discharge is a cause of ongoing paresthesias andpain. Many believe that in addition, this ectopic activity cantrigger and maintain central sensitization in the spinal cord, re-sulting in tactile hypersensitivity (allodynia and hyperalgesia)in the body parts innervated by the ganglion. This second ef-fect of ectopic DRG activity, however, is controversial. Zhangand collaborators now provide strong new support for thisidea by showing that lidocaine infusion into the DRG, withconsequent block of the ectopic DRG firing, considerably re-duces allodynia and hyperalgesia for the duration of the infu-sion (weeks). Here is a novel therapeutic approach that de-serves a try.

Clinical Science (34)

D. Sheffield, P.L. Biles, H. Orom, W. Maixner, D.S. Sheps:Race and sex differences in cutaneous pain perception. (Uni-versity of North Carolina at Chapel Hill, Chapel Hill, NC)Psychosomatic Medicine 2000;62:517–523.

The purpose of this study was to determine race and sex differ-ences in cutaneous pain perception. Pain perception was mea-sured using a suprathreshold evaluation of pain intensity andpain unpleasantness to a series of thermal stimuli in 27 whites(14 men and 13 women) and 24 African-Americans (12 menand 12 women). Blood pressure, depressive symptoms, anxietystate levels, and negative mood were assessed before pain test-ing to examine whether they might account for any sex or racedifferences in pain perception that emerged. African-Ameri-cans rated the stimuli as more unpleasant and showed a ten-dency to rate it as more intense than whites. Women showed atendency to rate the stimuli as more unpleasant and more in-tense than men. In addition, systolic blood pressure was in-versely related to pain intensity. After statistically adjusting forsystolic blood pressure, sex differences in pain unpleasantnesswere reduced and sex differences in pain intensity were abol-ished; race differences were unaltered. These differences in painperception may be associated with different pain mechanisms:in the case of sex, differences in opioid activity and barorecep-tor-regulated pain systems; in the case of race, unmeasuredpsychological characteristics are suggested by the larger differ-ences in ratings of pain unpleasantness than pain intensity.

Comment by Mauricio Orbegozo, MD.This is a study where the authors look to elucidate whether

there was a difference in cutaneous pain perception deter-mined by race or sex. In general, it is a very well-designedstudy where 2 different groups were evaluated, 1 of 27 whites


and 1 of 24 African-Americans with close to half and half dis-tribution of men and women. Pain perception was measuredusing pain intensity and pain unpleasantness to a series of ther-mal stimuli. Five different temperatures were used on eachsubject ranging from 458C to 498C. The pain scoring was car-ried upon a scale from 0 to 150 represented as a line where theevaluated subject had to mark the line at a certain height ac-cording to their pain perception. The conclusions reached inthe study show that, in general, whites rated the thermal stim-uli less painful than African-Americans. The results show atendency for men to rate the thermal stimuli as less painfulthan women did. One of the interesting findings in this studywas that the pain differences between men and women werediminished after statically adjusting for systolic blood pressurelevel. However, the pain intensity and the pain differences af-ter adjusting for systolic blood pressure were unaltered forrace differences.

In addition, it was also found that pain perception and painrating was inversely proportional to systolic blood pressure.The hypoalgesia caused by increased systolic blood pressure isa poorly understood mechanism. Several studies have shownthat in hypertensive rats there is increased opioid activity inbrain tissue. These studies have suggested that at the increaseof the pain threshold in subjects who have elevated blood pres-sure may be related to opioid activity. It is important to men-tion that in order to establish a definite correlation betweensystolic blood pressure elevation and the decreased pain per-ception more studies have to be done.

Another important point in this study is the influence ofpsychological factors on pain perception. In general, it wasseen that individuals that were psychologically rated as depres-sive had a higher rating of the pain compared to individualsthat tested as high for anxiety.


Joseph Colin, Olivier Prisant, Béatrice Cochener, Olivier Les-cale, Bénédicte Rolland, Thanh Hoang-Xuan: Comparison ofthe efficacy and safety of valaciclovir and acyclovir for thetreatment of herpes zoster ophthalmicus. (Hospital Morvan,Brest, France) Ophthalmology 2000;107:1507–1511.

This randomized, double-blinded study compared the efficacyand safety of valaciclovir and acyclovir in immunocompetentpatients with herpes zoster ophthalmicus. One hundred tenimmunocompetent patients with herpes zoster ophthalmicusdiagnosed within 72 h of skin eruption were treated; 56 wereallocated to the valaciclovir group and 54 to the acyclovirgroup. Patients randomized to the valaciclovir group received2 500-mg tablets of valaciclovir 3 times daily and 1 tablet ofplacebo twice daily. Patients in the acyclovir group received 1800-mg tablet of acyclovir 5 times daily and 1 tablet of pla-cebo 3 times daily for 7 days. Main outcome measures in-cluded the frequency, severity, and duration of ocular compli-cations, patient records of zoster-associated pain, and theoutcome of skin lesions. Tolerance was also assessed on the in-cidence and types of adverse effects and changes in laboratoryparameters. The analysis was mainly descriptive and per-

formed on an intent-to-treat basis. Ocular complications ofherpes zoster ophthalmicus were similar in the valaciclovir andacyclovir treatment groups. The main complications were con-junctivitis (54% and 52%, respectively), superficial keratitis(39% and 48%, respectively for punctate keratitis; 11 in eachgroup for dendritic keratitis), stromal keratitis (13% in eachgroup) and uveitis (13% and 17%, respectively). The long-term outcomes of these ocular complications were favorableand similar in both treatment groups. Pain duration, severity,and outcome of skin lesions were similar between groups.Most patients reported prodromal pain. After 1 month, 25%of the patients in the valaciclovir group and 31% in the acyclo-vir group still reported pain. The percentage of patients experi-encing postherpetic neuralgia decreased during follow-up. Thetolerance to acyclovir and valaciclovir was comparable andconsidered good. The most frequent adverse events were vom-iting and edema of the eyelids or face (3%–5%). Three seriousadverse events not linked to the study drugs occurred. Valaci-clovir is as effective as acyclovir in preventing ocular complica-tions of herpes zoster ophthalmicus, including conjunctivitis,superficial and stromal keratitis, and pain. Tolerability of the 2drugs is similar, but the dosing schedule of valaciclovir is simpler.

Comment by Mauricio Orbegozo, MD.This is a study comparing the efficacy in the treatment of

herpes zoster ophthalmicus and its ophthalmologic complica-tions and sequelae between valaciclovir and acyclovir. The ini-tial review of the incidence and the associated ophthalmologiccomplications of untreated herpes zoster ophthalmicus is con-cise and educational for physicians who do not interact withthese kind of patients frequently. As pain physicians, it is partof our daily practice to deal with patient compliance to themedication treatment we prescribe. In this sense, this articleprovides comparison between 2 medications that are very sim-ilar in the efficacy profiles as well as their control of complica-tions, but with acyclovir there is question of whether patientsmight be more compliant to the lower dosing frequency of val-aciclovir. Results overall are similar between both drugs, butin terms of complications, although not statistically signifi-cant, the percentage is consistently lower with valaciclovirthan acyclovir. The fact stated in this article regarding the bio-availability of valaciclovir being similar to that of intravenousacyclovir may account for this. The high incidence of irrevers-ible ophthalmic complications such as anatomical loss of aneye (50%–70%) in untreated herpes zoster ophthalmicusmakes the question of patient compliance with treatment acrucial one. As physicians, we may not realize that for a pa-tient there might be a significant difference between interrupt-ing their daily life 3 times to take a medication instead of 5times. In summation, this is a well-designed study with validconclusions that would impact our practice of medicine.


Mary E. Greipp: A follow-up study of 14 young adults withcomplex regional pain syndrome type I. (Hospital Morvan,Brest, France) J Neurosci Nurs. 2000;32:83–88.


This study evaluated the symptom experience and functionalstatus of 27 young adults with reflex sympathetic dystrophy syn-drome, now known as complex regional pain syndrome (CRPS)type I. All were originally diagnosed and studied 12 years ago.Only 15 subjects could be located; 14 participated in the re-search. A descriptive exploratory design was utilized. A tool wasdesigned to gather data about daily living variables, psychologi-cal variables, and symptom variables. Although many questionsrequired the use of Likert scales, there were some open-endedquestions to capture the qualitative descriptions of the partici-pant’s symptom experiences. Findings contribute to the clini-cal literature about CRPS and its effect on clients over time.

Comment by Mauricio Orbegozo, MD.This paper is a follow-up interview on 14 patients diag-

nosed with complex regional pain syndrome (CRPS) type Imore than a decade ago. The author created a tool with thepurpose of gathering data in 3 different aspects such as: cur-rent activity levels, psychosocial assessment, and symptom ex-periences. This data were gathered in a questionnaire form.The first 2 sections (current acting levels and psychosocial as-sessment) are questions to be answered on a 4-point Likertscale and the last part (symptom experiences) is an open-endedquestion section where the subject can answer in a more de-scriptive manner. What is particular about the population ofpatients in this study is the fact that all were diagnosed at anearly age (childhood or as young adults). This yielded an inter-esting set of results. As far as current activity levels, more thattwo-thirds of the patients were able to perform basic daily liv-ing activities and at least 50% of them can perform morestrenuous activities such as running, climbing stairs, and driv-ing a car. The results above extrapolate well into the psychoso-cial assessment where greater than 90% considered themselvesself-sufficient. Of interest was the fact that there was no de-pression or overwhelming psychiatric morbidity reported.This could be because at a younger age of onset for CRPS typeI, more effective coping skills can be developed that would aidthese patients in adaptation to daily life. It is not surprisingthat in symptom experience the most common was continuingpain, followed by limitations in range of motion. In summa-tion, this study sheds light into an aspect that has not been re-searched in an extensive manner, which is a long-term follow-up of patients suffering from CRPS type I and how theyadapted to daily life. Although conclusions reflect valid facts,the sample size is small and larger population including pa-tients who develop CRPS type I at later stages in life may pro-vide us with crucial information in a general set of patients.


Marius A. Kemler, Gerard A.M. Barendse, Maarten van Kleef,Mirjam G.A. Oude Egbrink: Pain relief in complex regionalpain syndrome due to spinal cord stimulation does not dependon vasodilation. (Maastricht University Hospital, Maastricht,The Netherlands) Anesthesiology 2000;92:1653–1660.

This study aimed to assess whether pain relief in complex re-gional pain syndrome (CRPS after spinal cord stimulation

(SCS) is, in fact, dependent on vasodilation. In addition, thestudy attempted to determine which of the potential mecha-nisms may cause the vasodilatory effect that is generally foundafter SCS. Twenty-four of 36 patients with unilateral CRPS re-sponded to the test of SCS. Twenty-two of the 24 responders(hand, n 5 14; foot, n 5 8) who had undergone previous sym-pathectomy were enrolled in the study. In addition, 20 controlsubjects (10 controls for each extremity) were studied. Bymeans of laser Doppler flowmetry, the skin microcirculationof the patients was measured bilaterally while the SCS systemwas switched off and while it was activated. Control subjectswere tested only once. The ratio of the rest flow at heart leveland the dependent position was defined as the vasoconstrictedindex. Both in affected hands and feet, patients were found tohave lower vasoconstriction indices (P , 0.01) as comparedwith controls, indicating a decreased sympathetic tone. Apply-ing SCS did not result in any microcirculatory change as com-pared with the baseline or the contralateral clinically unaf-fected side. Conclude that the study failed to show that SCSinfluences skin microcirculation in patients with CRPS and alow sympathetic tone. Therefore, it was also concluded thatpain relief in CRPS due to SCS is possible without vasodila-tion. Because sympathetic activity was greatly decreased in thepatients, these results support the hypothesis that the vasodila-tion that is normally found with SCS is due to an inhibitory ef-fect on sympathetically maintained vasoconstriction.

Comment by Hemmo A. Bosscher, MD.SCS probably provides pain relief independent of increases

in blood flow to the affected area. There may be several weak-nesses in this study. All patients underwent prior sympathec-tomy. As every pain management specialist knows, the resultsof these procedures are variable. That leaves a group of painpatients with CRPS I that is either predominantly sympatheti-cally mediated or sympathetically independent, with variabledegrees of sympathetic blockade. In addition, only part of theperipheral circulation is measured with a device which accu-racy has not yet been confirmed. Many variables are intro-duced in this study making a statement that there are no differ-ences between the treatment group and the control somewhatstrong. In my opinion: pain relief in complex regional painsyndrome due to spinal cord stimulation may not depend onvasodilatation.


J. Lillesø, N.A. Hammer, J.L. Pedersen, H. Kehlet: Effect of pe-ripheral morphine in a human model of acute inflammatorypain. (Hvidovre University Hospital, Hvidovre, Denmark) BRJ Anaesth 2000;85:228–232.

This study used a randomized, double-blinded, placebo-con-trolled, three-way crossover design in a human model of acuteinflammatory pain (heat injury). Eighteen healthy volunteerswere studied who each received morphine locally (2 mg), mor-phine systemically (2 mg), or placebo on three separate studydays. The subjects received morphine infiltration subcutane-ously (s.c.) 1 h before heat injury (478C, 7 min) and naloxone


infiltration s.c. (0.2 mg) 2.5 h after the heat injury. Hyperalge-sia to mechanical and heat stimuli were examined using vonFrey hairs and thermodes, and pain was rated using a visualanalogue scale. The burns produced significant hyperalgesia,but local morphine infiltration neither reduced pain during theburn, nor primary or secondary hyperalgesia to mechanicaland heat stimuli after the burn. Conclude peripherally appliedmorphine had no acute antinociceptive effects in this humanmodel of acute inflammatory pain.

Comment by Hemmo A. Bosscher, MD.This study is well controlled for placebo effect and the sys-

temic effect of subcutanuously injected morphine. One of thefew criticisms that can be made is the amount of narcotic in-jected. This may not be enough to bind to a sufficient numberof receptors. One would expect some role for peripheral opi-oid receptors. The other comment would be that this type ofinjury (mainly small fiber involvement in this case) does notrepresent all types of nociception and, therefore, the peripheralaction of morphine can not be excluded for different types ofnociception. But overall this is a convincing study, consistentwith the literature.


M.C. Lewis, J.P. Lafferty, M.S. Sacks, V.S. Pallares, M. Ter-Riet: How much work is required to puncture dura withTuohy needles? (Veterans Affairs Medical Center/Jackson Me-morial Medical Center, University of Miami, Miami, FL) BR JAnaesth 2000;85:238–241.

This study was designed to evaluate whether bevel orientationor patient position alters the force necessary to produce duralpuncture. A constant hydrostatic pressure was applied to thesubdural surface, either high or low, simulating the sitting andlateral positions. A 17-gauge Tuohy needle was advancedthrough the dura with the bevel oriented parallel or perpendic-ular to dural fibres. Travel distance and peak force at whichdural penetration occurred was measured under both pressureconditions. The work required to produce dural penetrationwas calculated. Greater force and work were required to pene-trate dura in the perpendicular orientation (P , 0.05), regard-less of the subdural pressure exterted. Dural displacement wassimilar under both pressure conditions.

Comment by Hemmo A. Bosscher, MD.Work is the product of displacement and force (the area un-

der the curve). The same amount of work is required whetherthe dura is under pressure (sitting position) or not (lyingdown). This is surprising. Absolute force is, therefore, not themost important factor. Penetration of the dura probably de-pends more on local pressure, the area of contact between nee-dle and dura, and the structure of the dura (eg, fiber direction).A sharp needle will obviously penetrate much easier than ablunt one. Considering the shape of a Tuohy needle you wouldexpect that the area of contact not only depends on orientationof the needle, but also strongly on the angle at which the durais approached. Since dural puncture with a Tuohy needle in a

young person almost invariably results in a “spinal headache”most benefit will be obtained from reducing the change of du-ral puncture. This study supports the concept of putting thebevel of the needle perpendicular to the fiber direction to re-duce this change.


Sue A. Ferguson, William S. Marras, Purnendu Gupta: Longi-tudinal quantitative measures of the natural course of lowback pain. (Ohio State University, Columbus, OH) Spine2000;25:1950–1956.

This prospective study compared traditional self-report mea-sures of low back pain recovery with quantitative measure ofrecovery. Sixteen occupational and 16 non-occupational pa-tients with low back pain were recruited. Recovery was moni-tored prospectively every 2 weeks for 3 to 6 months, usingsubjective work status, pain symptoms, activities of daily liv-ing, and objective functional performance probability (trunkkinematics). Return to work underestimated the percentage ofsubjects impaired, as compared with all other outcome mea-sures. Symptoms, activities of daily living, and functional per-formance probability all showed similar patterns of recoveryfor 0 to 12 weeks. At 14 weeks, there was a lag in functionalperformance recovery. Both symptoms and activities of dailyliving indicated that 80% of the population was recovered,whereas functional performance indicated the figure to be68%. Conclude that the objective kinematic functional perfor-mance measure of recovery quantifies a different aspect of im-pairment not evaluated by traditional subjective measures. Useof several outcome measures may lead to a better understand-ing of low back pain recovery or residual impairment, whichmay minimize the risk of recurrent injury.

Comment by Hemmo A. Bosscher, MD.This study evaluates several traditional and not so tradi-

tional quantitative measures in the recovery of low back pain.The authors hypothesize that a better understanding of thenatural course of low back pain (LBP) recovery may providethe knowledge necessary to prevent high cost recurrent lowback injuries. But the relationship between acute low backpain, its recovery, and the subsequent recurrence of LBP is notstudied here at all. However the study offers some other inter-esting information. The traditional outcome measure “back towork” is a very insensitive one. It depends on the job ratherthan the severity of the LBP. A relatively new functional out-come measure was introduced: the lumbar motion monitor, adevice that evaluates trunk kinematics. This measure seemsmore important in later stages of recovery.


Eli Molde Hagen, Hege R. Eriksen, Holger Ursin: Does early in-tervention with a light mobilization program reduce long-termsick leave for low back pain? (Central Hospital in Hedmark,Ottestad, Norway) Spine 2000;25:1973–1976.


This randomized, controlled clinical trial investigated the ef-fect of a light mobilization program on the duration of sickleave for patients with subacute low back pain. Early interven-tion with information, diagnostics, and light mobilization maybe a cost-effective method for returning patients quickly tonormal activity. In this experiment, patients were referred to alow back pain clinic and given a simple and systematic pro-gram as an outpatient treatment. Patients sick-listed 8 to 12weeks (N 5 457) for low back pain were randomized into twogroups: an intervention group (n 5 237) and a control group(n 5 220). The intervention group was examined at a spineclinic and given information and advice to stay active. The con-trol group was not examined at the clinic, but was treated withconventional primary health care. At 12-month follow-up as-sessment, 68.4% in the intervention group had returned tofull-duty work, as compared with 56.4% in the control group.Conclude that early intervention with examination, informa-tion, and recommendations to stay active showed significanteffects in reducing sick leave for patients with low back pain.

Comment by Susan Anderson, MD.This is a randomized controlled clinical trial to compare

patients that have been sick listed for more than 8 weeks inNorway. Comparison was between a control group that re-ceived conventional primary health care and an interventiongroup that was examined at a spine clinic, given information,and advised to stay active. The authors wanted to examine ifan early intervention with information, diagnostics, and lightmobilization may be a cost-effective method for returning pa-tients quickly to normal activity. This study involved 457 pa-tients that were sick listed 8 to 12 weeks for low back pain.The inclusion criteria for the study was based on 1) 8 to 12weeks being “sick-listed,” 2) age (18 to 60 years), and 3) diag-nosis that included back pain, low back pain, leg and thighpain, back pain without sciatica, and sciatica. Exclusion crite-ria included pregnancy, recent low back trauma, cauda equinasymptoms, cancer, osteoporosis, rheumatic low back disease,and ongoing low back treatment. The intervention used wasmodification of Indahl’s light mobilization program where thepatient was referred to a spine clinic, answered standard ques-tionnaires, and was interviewed and examined by a treatmentteam consisting of a physician and a physiotherapist. Any so-matic findings during the examination were explained to thepatient and information was given about their importance. Allradiographs were shown and explained. The idea was to edu-cate the patient and dedramatize their problems. The patientwas assured of a good prognosis and informed of the impor-tance of remaining active to avoid development of muscle dys-function. The physiotherapist individually advises the patienton how to train and stretch at home. They were also advisedon how to manage the back pain and resume normal activity.The patients in the control group were not examined at theclinic, but were treated with primary health care, which in-cluded at least one visit to a general practitioner. The patientswere reassessed at 3 months, 6 months, and 12 months. Theassessment was to determine if the patient had returned to fullduty work. At each of the assessments, the intervention grouphad a higher percentage of patients that had returned to fullduty work. At the 12-month follow-up, 68.4% in the interven-

tion group had returned to full duty work as compared with56.4% in a controlled group.

This study demonstrates that a consultation with thoroughexamination, information, reassurance, and encouragementshows a significant effect in reducing sick leave for patientswith low back pain as compared to the conventional healthcare guidelines used by general practitioners that tend to rec-ommend bed rest, caution, and reduced activities. The authorssuggest that information and fear reduction when offered sys-tematically may reduce the fear of “doing something wrong”to the back. This may then prevent unnecessary activity andlong sick leave.


Massimo Varenna, Francesca Zucchi, Daniel Ghiringhelli: In-travenous clodronate in the treatment of reflex sympatheticdystrophy syndrome: a randomized, double blind, placebo-controlled study. (Istituto Ortopedico Gaetano Pini, Milan,Italy) J Rheumatol 2000;27:1477–1483.

This study evaluated the efficacy of intravenous (IV) clo-dronate in patients with reflex sympathetic dystrophy syn-drome (RSDS) and assessed the urinary excretion of type 1collagen crosslinked N-telopeptide (NTx) before and aftertreatment. Thirty-two patients with RSDS were randomized toreceive either IV Clodronate 300 mg daily for 10 consecutivedays or placebo. Forty days later, the placebo treated patientsreceived the clodronate treatment. Outcome measures in-cluded as a primary endpoint the visual analog scale of pain(VAS, range 0–100); secondary endpoints were a clinical glo-bal assessment (CGA, range 0–3) and an efficacy verbal score(EVS, range 0–3). Clinical and biochemical assessments wereperformed before the treatment, 40 (T40), 90 (T90), and 180(T180) days later. At T40 the 15 patients randomized to clo-dronate treatment showed significant decreases of VAS andCGA (P 5 0.002, P 5 0.001, respectively). Compared with theplacebo group (17 patients), significant differences were foundin all clinical variables. A further clinical improvement was ob-served throughout the study. Pooling the results of all 32 pa-tients after clodronate treatment, at T180 the overall percent-age decrease of VAS was 9.32 6 15.6% with 30 patientssignificantly improved or asymptomatic. Significant inversecorrelations between baseline NTx values and decreases ofVAS were found at T90 (P 5 0.03) and T180 (P 5 0.01). Noadverse events related to treatment occurred. Conclude that a10-day IV clodronate course is better than placebo and effec-tive in the treatment of RSDS. NTx seems to be a predictivefactor for clodronate efficacy.

Comment by Susan Anderson, MD.This is a randomized double blind placbo controlled study

to evaluate the efficacy of intravenous clodronate in patientswith reflex sympathetic dystrophy syndrome (RSDS) or com-plex regional pain syndrome type I. It is also to assess the uri-nary excretion of type I collogen crosslink N-telopeptide(NTx) before and after the treatment. Thirty-two patients withcomplex regional pain syndrome type I were randomized to re-


ceive either a placebo or IV clodronate 300mg daily for 10consecutive days. At the end of 40 days, the placebo group wasthen treated with the clodronate. The primary endpoint mea-sures with the visual analog scale (VAS, range 0–100) and asecondary endpoint was the clinical global assessment (CGA,range 0–3), and an efficacy vocal score (EVS, range 0–3). Inaddition, the patient had clinical and biochemical assessmentsperformed before the treatment at 40 days, at 90 days, and at180 days later. The purpose of the study was valued at the effi-cacy of the IV clodronate in pain relief. The second purposewas to evaluate the possibility of using NTx as a predictingfactor for evaluating complex regional pain syndrome type I orthe clodranate efficacy. On day 40, 15 patients that were ran-domized to the clodronate treatment showed significant de-creases in their VAS and CGA when compared with the pla-cebo group with 17 patients.

In addition, the patients who had originally received pla-cebo infusions showed decreased VAS and CGA scores after40 days of treatment with the clodronate when compared totheir VAS and CGA scores after placebo. At 180 days, the pa-tients continued to show significant improvement or were asymp-tomatic. Bisphosphonates have been proposed since 1988 forthe treatment of CRPS type I. The most frequently used ispamidronate, which is given intravenously showing variedresults. The pamidronate did not seem to be well tolerated. Al-endronate is also given intravenously demonstrating good effi-cacy. It, however, has a high relapse rate. Clodronate was cho-sen for this study because it was efficacious in treatment ofvarious painful skeletal disorders and was more tolerable andsafe than the pamidronate. The length of the time of the studywas chosen to be 10 consecutive days so that it followed thestudy with successful use of pamidronate. These results sug-gest that a 10-day IV clodronate course is better than placeboand is an effective complex regional pain syndrome type Itreatment that may induce prompt and long lasting improve-ment. This study also attempted to demonstrate NTx as a pre-dictive factor for clodranate efficacy. While NTx has shown tobe a specific and sensitive marker of bone resorption, in thisstudy, they found a low association between high NTx valuesand the complex regional pain syndrome type I. This findingcould weaken the relationship between NTx baseline valuesand the responsiveness to clodronate treatment. It should benoted, however, that there were significant immerse correla-tions found between the baseline NTx values and in the painimprovement measured on the percentage change of VAS at 90days and 180 days. Therefore, while significant inverse corre-lations may have been determined, and the NTx may be apromising tool, it is not yet possible to determine the predic-tive rolls of NTx as a marker.


Douglas Ormrod, Karen Goa: Valaciclovir: a review of its usein the management of herpes zoster. (Adis International Lim-ited, Auckland, New Zealand) Drugs 2000;59:1317–1340.

This study compared the effectiveness of valaciclovir (1000 mg3 times daily for 7 days) and aciclovir (800 mg 5 times daily

for 7 days) in controlling the symptoms of acute herpes zoster.Valaciclovir was found to alleviate zoster-associated pain andpostherpetic neuralgia significantly faster than aciclovir. A 14-day regimen of valaciclovir showed no significant advantageover the 7-day regimen. A smaller trial in Japanese patients fo-cusing primarily on the cutaneous (rash) signs of herpes zosterconfirmed the similar efficacy of valaciclovir and aciclovir inthe 7-day regime. Valaciclovir and aciclovir demonstrated sim-ilar efficacy for the control of cutaneous lesions and ocularcomplications in patients with zoster ophthalmicus. Startingtreatment later than 72 h after rash onset did not significantlyreduce the beneficial effect of valaciclovir on the duration ofzoster-associated pain, suggesting that valaciclovir might beeffective when given later than previously thought. However,valaciclovir should ideally be given as soon as possible aftersymptoms appear. Valaciclovir was well tolerated with nauseaand headache as being the most commonly reported adverseevents. The adverse events profile of the agent was similar tothat seen with aciclovir or famciclovir. Conclude that the effi-cacy of valaciclovir for the treatment of herpes zoster has beenconfirmed and extended by follow-up studies in herpes zosterophthalmicus, in Japanese patients, and in the wider primarycare setting. Valaciclovir is at least equivalent to, and better incertain parameters than, aciclovir and appears to have similarefficacy to famciclovir 500 mg 3 times daily.

Comment by Susan Anderson, MD.This is a review article on the antiviral drug valaciclovir.

The varicella zoster virus (VZV) is commonly treated with theantiviral drug aciclovir. However, aciclovir has a low oral bio-availability that limits its efficacy in the treatment of herpeszoster. Valaciclovir was developed in order to have a morereadily absorbed oral antiviral drug. When valaciclovir wascompared to aciclovir in a large study, it was noted that valac-iclovir was as effective in controlling the symptoms of acuteherpes zoster. It was also noted valaciclovir alleviated zosterassociated pain and postherpetic neuralgia significantly fasterthan aciclovir. Also, there was no significant advantage oftreating valaciclovir 14 days versus 7 days; therefore, a 7-dayregimen is recommended. In a smaller trial from Japan that fo-cused primarily on the cutaneous (rash) signs of herpes zoster,there was also confirmation of similar efficacy of aciclovir andvalaciclovir in a 7-day regimen. The similarity in efficacy wasnot only for cutaneous lesions but also for ocular complica-tions in patients with zoster ophthalmicus. In a large con-trolled trial, they compared valaciclovir and famciclovir. Thisshowed similar efficacy in resolution of acute herpes zosterrashes shortening the duration of postherpetic neuralgia. Itwas purposed in the article that the therapeutic window forbeneficial treatment with valaciclovir and zoster associatedpain may be wider that previously though. It is still recom-mended that valaciclovir be ideally given as soon as possibleafter symptoms appear. However, starting treatment after 72hours after rash onset did not significantly reduce the benefi-cial effect of the valaciclovir on duration of zoster associatedpain. Valaciclovir is known to be well tolerated with nauseaand headache being the most commonly reported adverseevents. The adverse events profile of valaciclovir is similar toaciclovir or famciclovir. The purpose of this review was to


present an overview of the pharmacodynamic/pharmacoki-netic properties and therapeutic efficacy in the assessment ofpain in herpes zoster in comparison with known agents of acic-lovir, famciclovir, and/or placebo.

It is concluded that valaciclovir is an efficacious agent inthe treatment of herpes zoster and herpes zoster ophthalmicus.It’s at least as efficacious as aciclovir and has similar efficacy tofamciclovir. It is well tolerated with a similar side effect profileas aciclovir and famciclovir.

Headache (44)

Alan Rapoport, John Edmeads: Migraine: the evolution of ourknowledge. (The New England Center for Headache, Stamford,CT) Arch Neurol 2000;57:1221–1223.

This brief article described the evolution of knowledge regard-ing headache pain, namely migraines. By exploring historicalliterature, quotes related to headache pain and treatments arediscussed. Early clinical developments are outlined with refer-ences to Hippocrates, Aretaeus the Cappadocian, and Galen.The theories of Thomas Willis regarding pain sensitivity arealso provided. Conclude that the history of headache illus-trates that the acquisition of understanding is a long-term,evolving process.

Headache (45)

Elliot A. Schulman, Roger K. Cady, Dan Henry: Effectivenessof sumatriptan in reducing productivity loss due to migraine:results of a randomized, double blind, placebo-controlled clin-ical trial. (Center for Headache Management, Springfield, PA)Mayo Clin Proc 2000;75:782–789.

This clinical trial determined the effect of sumatriptan on mi-graine-related workplace productivity loss. Adult migrainesufferers self-injected 6 mg of sumatriptan or matching pla-cebo to treat a moderate or severe migraine within the first 4 hof a minimum of an 8-h work shift. Outcome measures in-cluded productivity loss and number of patients returning tonormal work performance 2 h after injection and across thework shift, time to return to normal work performance, andtime to headache relief. A total of 206 patients underwentscreening, 140 (safety population) of whom returned for clinictreatment. Of these 140 patients, 119 received migraine treat-ment in the workplace. Sumatriptan treatment tended to re-duce median productivity loss 2 h after injection comparedwith placebo (25.2 versus 29.9 min, respectively) (P 5 0.14).Significant reductions in productivity loss were obtained acrossthe work shift after sumatriptan treatment compared with pla-cebo (36.8 versus 72.6, respectively) (P 5 0.001). Significantlymore sumatriptan-treated patients versus placebo-treated pa-tients experienced shorter return to normal work performanceat 2 h and across the work shift. Significantly more sumatrip-tan-treated patients experienced headache relief 1 h after injec-tion compared with placebo-treated patients. Conclude thatacross an 8-h work shift, sumatriptan was superior to the pla-cebo in reducing productivity loss due to migraine.

Medicine (46)

Peter N. Watson: The treatment of neuropathic pain: antide-pressants and opioids. (University of Toronto, Ontario, Can-ada) Clin J Pain 2000;16:S49–S55.

This article reviewed the scientific data on antidepressants andopioids, which are largely confined to randomized controlledtrials in two neuropathic pain conditions that have proved tobe good models for clinical investigation. A review of literaturewas conducted using MEDLINE, CINAHL, and the CochraneDatabase regarding postherpetic neuralgia and painful dia-betic neuropathy. The use of the older antidepressants such asamitriptyline in neuropathic pain was extensively supportedby the literature. However, newer randomized controlled trialssupported the use of opioids. Conclude that first-line therapyfor neuropathic pain may be either an older generation antide-pressant such as amitriptyline or nortriptyline or the anticon-vulsant gabapentin. For refractory cases, chronic opioid ther-apy may be the only avenue of relief, and evidence is accumulatingthat this approach is safe if proper guidelines are observed.

Medicine (47)

Zbigniew Zylicz: Ethical considerations in the treatment ofpain in a hospice environment. (Hospice Rozenheuvel, Ro-zendaal, The Netherlands) Patient Education and Counseling2000;41:47–53.

This article discussed some specific ethical problems encoun-tered in hospice practice. Patient’s autonomy with all its ad-vantages and disadvantages are highlighted. Ethical consider-ations with regard to risk taking and the treatment of pain arediscussed. The needs of the patients are central to the discus-sion. Myths regarding opioids and pain therapy goals are ad-dressed, as are approaches to treating intractable pain anddealing with patients who request assisted death. Acceptanceof death may result in an active and creative attitude. Con-clude that although scientific evidence of the processes takingplace is still lacking, the modern hospice may be seen as a com-plementary, mainstream institution contributing to the devel-opment of whole medicine.

Neurology (48)

Carolien M. Kooijman, Pieter U. Dijkstra, Jan H.B. Geertzen, Al-bert Elzinga, Cees P. Van der Schans: Phantom pain and phan-tom sensations in upper limb amputees: an epidemiological study.(University Hospital Groningen, Groningen, The Netherlands)Pain 2000;87:33–41.

This study determined the prevalence and factors associatedwith phantom pain and phantom sensations in upper limb am-putees in The Netherlands. Additionally, the relationship be-tween phantom pain, phantom sensations, and prosthesis usein upper limb amputees was investigated. One hundred twenty-four upper limb amputees participated in the study. Subjectswere asked to fill out a self-developed questionnaire scoring the


following items: date, side, level, and reason of amputation,duration of experienced pain before amputation, frequencieswith which phantom sensations, phantom pain, and stumppain are experienced, amount of trouble and suffering experi-enced, respectively, related to these sensations, type of phan-tom sensations, medical treatment received for phantom painand/or stump pain, and the effects of the treatment, self medi-cation, and prosthesis use. The response rate was 80%. Theprevalence of phantom pain was 51%, of phantom sensations76%, and of stump pain 49%; 48% of the subjects experi-enced phantom pain a few times per day or more. Moderate tosevere suffering from phantom pain was experienced by 64%of the respondents. A significant association was found betweenphantom pain and phantom sensations (relative risk 11.3) andbetween phantom pain and stump pain (relative risk 1.9). Noother factors associated with phantom pain or phantom sensa-tions could be determined. Only 4 patients received medicaltreatment for their phantom pain. Phantom pain is a com-mon problem in upper limb amputees that causes consider-able suffering for the subjects involved. Only a small numberof subjects are treated for phantom pain. Conclude that fur-ther research is needed to determine factors associated withphantom pain.

Neurology (49)

Jihad Khattab, Howard R. Terebelo, Basel Dabas: Phantom limbpain as a manifestation of paclitaxel neurotoxicity. (Provi-dence Hospital, Southfield, MI) Mayo Clin Proc 2000;75:740–742.

This case report described 2 patients with prior amputationwho experienced phantom limb pain (PLP) after receivingpaclitaxel therapy. A third patient experienced disabling neu-rotoxicity in the extremity of a prior ulnar nerve and tendontransposition after receiving paclitaxel. This unique syndromeshould be identified as a direct causal effect of paclitaxel. Thepathophysiology of PLP and the treatment options are re-viewed. Conclude that physicians should be aware that PLPcan occur after initiation of paclitaxel.

Neurology (50)

Burt Yaszay, Charles K. Jablecki, Marc R. Safran: Zoster pare-sis of the shoulder. (Stanford University School of Medicine, Stan-ford, CA) Clinical Orthopaedics and Related Research 2000;377:112–118.

A case of unilateral left C5-C6 segmental paresis attributableto herpes zoster in an otherwise healthy individual and a cur-rent review of literature are presented. A case of zoster paresisof the shoulder muscles is presented to remind the orthopediccommunity that this diagnosis may be confused with other di-agnoses, including rotator cuff tear, and should be consideredin the differential diagnosis of shoulder pain and shoulder gir-dle muscle weakness.

Neurology (51)

J.J. Van Hilten, W.J.T. Van de Beek, B.O. Roep: Regional painsyndrome: a distinct clinical entity associated with HLA-DR13. (Leiden University Medical center. Leiden, The Nether-lands) Ann Neurol 2000;48:113–116.

This report discussed 26 patients with a distinct phenotype ofcomplex regional pain syndrome that progressed toward amultifocal or generalized tonic dystonia. The dystonia initi-ated distally, involved mainly flexor muscles, and was associ-ated with sensory and autonomic symptoms. Dryness of theeyes or mouth and bladder and bowel disturbances were fre-quently reported. There was no increase in the familial preva-lence of autoimmune-mediated disease. Compared with con-trols, a significant elevation of HLA-DR13 was found in thepatients. Thus, HLA-DR13 may be a factor indicating suscep-tibility to this distinct phenotype of complex regional pain syn-drome.

Neurology (52)

C.A. Brookman, M.L.C Rutledge: Epidural abscess: case re-port and literature review. (Western General Hospital, Edin-burgh, Scotland) Reg Anesth Pain Med 2000;25:428–431.

A case of a 72-year-old woman who underwent adrenalec-tomy and groin dissection for recurrent malignant melanomaunder combined general and epidural anesthesia was pre-sented. On the fourth postoperative day, she developed signsof localized infection at the epidural site and a band of reducedsensation. Further neurological signs developed before the di-agnosis was made by magnetic resonance imaging scans. Shesubsequently underwent emergency laminectomy and drain-age of the epidural abscess. Conclude that delayed diagnosisallowed the development of significant morbidity before neu-rosurgical intervention and antibiotics were instituted.

Neurology (53)

David S. Goldstein, Cees Tack, Sheng-Ting Li: Sympathetic in-nervation and function in reflex sympathetic dystrophy. (Na-tional Institutes of Health, Bethesda, MD) Ann Neurol 2000;48:49–59.

This study examined sympathetic neurocirculatory functionand the role of sympathetic postganglionic nerve traffic inmaintaining the pain in 30 patients with reflex sympatheticdystrophy. Most had had the condition for more then 1 year,and 14 had undergone sympathectomy for the pain. Positronemission tomographic scanning after administration of 13N-ammonia was used to assess local perfusion, and 6-[18F]fluo-rodopamine was used to assess sympathetic innervation. Ratesof entry of norepinephrine in the regional venous drainage(spillovers) and regional plasma levels of L-dihydroxyphenyl-alanine (the immediate product of the rate-limiting enzymaticstep in norepinephrine biosynthesis) and dihydroxyphenylgly-col (the main neuronal metabolite of norepinephrine) were


measured with and without intravenous trimethaphan for gan-glion blockade. 13N-ammonia-derived radioactivity was lesson the affected side than on the unaffected side, whereas6-[18F]fluorodopamine-derived radioactivity was symmetrical.Thus, perfusion-adjusted 6-[18F]fluorodopamine-derived ra-dioactivity was higher on the affected side. Norepinephrinespillover and smaller arteriovenous increments in plasma lev-els of L-dihydroxyphenylalanine and dihydroxyphenylglycoldid not differ significantly between affected and unaffectedlimbs, although 4 patients had noticeably less norepinephrinespillover and smaller arteriovenous increments in plasma dihy-droxyphenylglycol on the affected side. Trimethaphan de-creased the pain in only 2 of 12 nonsympathectomized patients.The results indicate that patients with chronic unilateral reflexsympathetic dystrophy have decreased perfusion of the af-fected limb, symmetrical sympathetic innervation and norepi-nephrine synthesis, variably decreased release and turnover ofnorepinephrine in the affected limb, and failure of ganglionblockade to improve the pain in most cases. These findingssuggest augmented vasoconstriction, intact sympathetic termi-nal innervation, possibly impaired sympathetic neurotransmis-sion, and pain usually independent of sympathetic neurocircu-latory outflows.

Neurology (54)

Michael Stanton-Hicks: Complex regional pain syndrome (typeI, RSD; type II, causalgia): controversies. (The Cleveland ClinicFoundation, Cleveland, OH) Clin J Pain 2000;16:S33–S40.

In this review, the relationship of sympathetically maintainedpain and sympatholysis is examined, particularly as a neuro-pathic process that is found in many conditions including com-plex regional pain syndromes. This review also focused on re-cent observations proposing a pathologic basis in support ofdiagnosis and treatment of these disorders.

Neurology (55)

Robert H. Dworkin, Frederick M. Perkins, Elna M. Na-gasako: Prospects for the prevention of postherpetic neuralgiain herpes zoster patients. (University of Rochester School ofMedicine and Dentistry, Rochester, NY) Clin J Pain 2000;16:S90–100.

This review discussed the results of recent studies that haveidentified risk factors for the development of postherpetic neu-ralgia (PHN) and have implicated several peripheral and cen-tral mechanisms in its pathophysiology. These risk factors andmechanisms of PHN provide a basis for hypothesizing thatcombining antiviral therapy with analgesic treatment begin-ning as soon as possible after the onset of herpes zoster wouldreduce the risk of PHN beyond that achieved by antiviral ther-apy alone. Conclude this treatment approach would be ex-pected to reduce the risk of PHN in herpes zoster patients byattenuating acute pain and thereby preventing the initiation ofcentral mechanisms of chronic pain.

Neurology (56)

Misha-Miroslav Backonja: Anticonvulsants (antineuropathies)for neuropathic pain syndromes. (University of Wisconsin Hos-pital and Clinics, Madison, WI) Clin J Pain 2000;16:S67–72.

This review concentrated on randomized clinical trials of anti-convulsants for neuropathic pain syndromes. The discussionincluded the use of phenytoin, benzodiazepines, valproic acid,lamotrigine, and gabapentin (GBP). GBP has a favorable sideeffects profile, and based on the results of these studies, itshould be considered a first-line treatment for neuropathicpain. GBP mechanisms of action are still not thoroughly de-fined, but GBP is effective in relieving indexes of allodynia andhyperalgesia in animal models. It still remains to be seenwhether GBP is as effective in other painful disorders. Onesmall clinical trial with lamotrigine demonstrated improvedpain control in trigeminal neuralgia. Evidence in support ofthe efficacy of anticonvulsant drugs in the treatment of neuro-pathic pain continues to evolve, and benefits have been clearlydemonstrated in the case of GBP and carbamazepine. Moreadvances in our understanding of the mechanisms underlyingneuropathic pain syndromes should further our opportunitiesto establish the role of anticonvulsants in the treatment of neu-ropathic pain.

Comment by Enrique Reig, MD.The clinical efficacy of anticonvulsants is clearly estab-

lished after years of use in patients with chronic neuropathicpain. However, there are few controlled studies to supporttheir clinical efficacy. Not all anticonvulsant drugs have thesame mode of action, which explains why their relief of thedifferent symptoms of neuropathic pain (allodynia, hyperalge-sia, burning pain, etc.) is varied. Gabapentine is a first-choicedrug for relieving allodynia and hyperalgesia, but it is usuallyless effective for decreasing paresthesia and dysaesthesia.

This article does not refer to clonazepam (a benzodiazepineacting on GABA, which is useful in stabbing pain) or topira-mate. The latter is an antiepileptic drug with a good profile forthe treatment of neuropathic pain. It has a triple action mecha-nism: Na1 channel blockade, increased GABA transmission,and antagonism of the kainate-glutamate/AMPA.

Neurology (57)

Charles E. Argoff: New analgesics for neuropathic pain: thelidocaine patch. (North Shore University Hospital, Syosset,NY) Clin J Pain 2000;16:S62–266.

This article reviewed the basis for the development of thelidocaine patch and reviewed the reports of the clinical studiespublished. Potential uses of the lidocaine patch for other con-ditions in addition to postherpetic neuralgia (PHN) were alsodiscussed. Conclude that it has been clearly established thatthe lidocaine patch is a safe and effective treatment for PHNand it is recommended as a first-line treatment based on dem-onstrated efficacy, quick onset of action, lack of systemic ef-fects, and ease of use with other treatments.


Comment by Enrique Reig, MD.Intravenous lidocaine is used in pain units for the transient

relief of chronic neuropathic pain. If the analgesic result is sat-isfactory, some physicians start treatment with a lidocaine an-alogue, oral mexylithene. However, the latter drug is not al-ways well tolerated and its efficacy (in my opinion) is far lowerthan that of intravenous lidocaine. The recently marketedlidocaine patch is a highly recommended therapeutic alternativeif we are considering long-term treatment with lidocaine. Topi-cal agents act locally (skin, soft tissues, peripheral nerves) anddo not cause high blood levels (no higher than 0.6 micgr/mL).Topical 5% lidocaine decreases the ectopic discharges fromperipheral afferents, reducing nociceptive input to the CNS.There are few side effects and the main indication is posther-petic neuralgia and all those syndromes with peripheral neuro-pathic pain. The relief that can be expected after using topical5% lidocaine is not complete, and it can be associated withother types of drugs (anticonvulsants, antidepressants, analge-sics, etc.) to obtain a synergistic effect.

Neurology (58)

Ralf Baron: Peripheral neuropathic pain: from mechanisms tosymptoms. (Christian-Albrechts-Univerität Kiel, Kiel, Germany)Clin J Pain 2000;16:S12–20.

This review concentrates on the several independent patho-physiological mechanisms in both the peripheral and centralnervous system that are responsible for sensory symptoms aswell as spontaneous and evoked pains in peripheral neuropa-thies. These mechanisms can operate in concert in a single dis-ease entity and also in a single patient. Distinct pathophysio-logical mechanisms lead to specific sensory symptoms, forexample, dynamic mechanical allodynia and cold hyperalge-sia. It is also possible that the pain-generating mechanism andthe symptoms change during the course of the disease. A thor-ough analysis of sensory symptoms may reveal the underlyingmechanisms that are mainly active in a particular patient. Thetreatment of neuropathic pain is currently unsatisfactory. Inthe future, drugs will be developed that address specifically therelevant combination of mechanisms.

Comment by Enrique Reig, MD.This is an excellent article, which will be a landmark in the

approach to the treatment of neuropathic pain. There are sev-eral pathophysiological mechanisms, which can cause sensitivesymptoms and spontaneous or evoked pain. Mechanical orthermal hyperalgesia is caused by peripheral sensitization. Pin-prick hyperalgesia is correlated to the “wind-up” phenome-non. Allodynia has multiple triggering factors: central sensiti-zation, central reorganization and loss of inhibitory control.Paresthesia is explained by ectopic discharges due to the accu-mulation of Na1 channels, as with stabbing or paroxysmalpain. A hot or burning pain can be explained by peripheralsensitization and loss of inhibitory mechanisms. This explainswhy not all painful syndromes respond with the same efficacyto a given treatment. Neuropathic pain can occur in very dif-ferent forms. For instance, a diabetic neuropathy can be asso-

ciated with allodynia and hyperalgesia, or with burning andparoxysmal pain. A different treatment is required for each ofthese symptoms. From now on, we must use a different crite-rion to label painful neuropathic syndromes. Keeping to theabove example, we shall distinguish between diabetic neurop-athy with allodynia and diabetic neuropathy with burningpain.

Neurology (59)

Ribert G. Phelps, Seth Wilentz: Reflex sympathetic dystrophy.(Mount Sinai School of Medicine, New York, NY) Int J Der-matol 2000;39:481–486.

This review aimed to familiarize the dermatologist with the es-sential features of reflex sympathetic dystrophy. It highlightsareas that are most likely to be of interest to the dermatologist.Information regarding diagnosis, pathogenesis theories, andtreatment are included.

Comment by Enrique Reig, MD.This paper analyses RSD from the point of view of a spe-

cialist in dermatology. It addresses in depth the definition ofRSD (or the new name, CRPS type I), the symptoms requiredfor adequate diagnosis, some theories to explain this syn-drome, and some of the treatments available. It highlights theclinical pictures, which can cause RSD (trauma, ischemia, tu-mors, infection, neurological and iatrogenic causes), and par-ticularly dermatological syndromes (minor surgery, posther-petic neuralgia, Dupuytren, vasculitis . . .).

The treatment has a bipolar objective: to relieve pain in or-der to be able to apply appropriate physical therapy, whichwill allow recovery of the involved limb. There are more than60 treatments reported in the literature, suggesting that thereis no universal protocol. However, prevention of RSD, andparticularly the early onset of treatment are essential forachieving functional and pain relief. To suppress sympathetichyperactivity, nerve blocks (somatic and sympathetic), intra-venous regional blockade with guanethidine or reserpine, al-pha blockers (phentolamine), beta blockers (propranolol), andcalcitonine can be used.

No reference is made to anticonvulsants (gabapentine, topira-mate), antidepressants (ie, amitriptyline), intravenous lidocaine,or spinal cord stimulation.

Neurology (60)

J. M. Puig I Marí, E. Martinez-Miralles, X. Perich et al: Reflexsympathetic dystropy syndrome of the lower limbs in a renaltransplant patient treated with tacrolimus. (Hospital de Mar,Barcelona, Spain) Transplantation 2000;70:210–211.

This study describes the treatment of a 49-year-old womanwho received a kidney transplant from a cadaver donor andwas treated with tacrolimus. Three months later, the patientcomplained of severe pain in her lower limbs that affectedboth knees and ankles. Bone scintigraphy and magnetic reso-nance were consistent with reflex sympathetic dystrophy syn-


drome. Laboratory tests that included creatinine, glomerularfiltration rate, calcium, phosphate, urate, alkaline phosphatase,and parathormone were normal or near normal. Tacrolimuslevels were around 13 mg/mL. Clinical improvement appearedslowly and spontaneously during the following 3 months,without appreciable changes in the tacrolimus level. Concludethat in kidney transplant patients, tacrolimus could be a riskfactor for the development of a reflex sympathetic dystrophysyndrome.

Neurology (61)

Ghassan E. Kanazi, Ribert W. Johnson, Ribert H. Dworkin:

Treatment of postherpetic neuralgia: an update. (University ofRochester School of Medicine and Dentistry, Rochester, NY)Drugs 2000;59:1113–1126.

This article provided an update on recent developments in thetreatment of postherpetic neuralgia (PHN). In clinical trials,the topical lidocaine patch, gabapentin, and controlled releaseoxycodone have been shown to provide superior pain relief inpatients with PHN when compared with placebo. It has alsobeen demonstrated that the tricyclic antidepressant nortrip-tyline provides equivalent analgesic benefit when comparedwith amitriptyline, but is better tolerated. Based on these re-sults, nortriptyline can now be considered the preferred anti-depressant for treatment of PHN. The topical lidocaine patch,gabapentin, and controlled release oxycodone all appear to beas effective as tricycline antidepressants in the treatment of pa-tients with PHN, and the results of these recent studies suggestthat each of these treatments should be considered early in thecourse of treatment. Additional controlled trials are needed tocompare the efficacy and tolerability of these 4 treatments forpatients with PHN.

Neurology (62)

Wikberg, C. Andersson, F. Lithner: Signs of neuropathy in thelower legs and feet of patients with acute intermittent porphy-ria. (University of Umeå, Umeå, Sweden) J Intern Med 2000;248:27–32.

A total of 356 patients were registered and 339 of them (95%)participated in this neuropathy study. The chronic neurologi-cal signs were symmetrical and similar to those in type 1 dia-betic patients. Significant impairment was found concerningperception, EDB test, lower leg pain, ankle and knee tendonreflexes, but not concerning dry feet, loss of forefoot arch andhammer toes, on comparing patients with manifest versus la-tent acute intermittent porphyria (AIP). The neurological signswere more severe in the diabetic patients (n 5 298). Five AIPpatients had permanent quadriplegia after severe attacks. Con-clude that patients with manifest AIP had significantly moresigns of distal chronic, symmetrical neuropathy of the axonaltype than did patients with latent AIP. More grave neurologi-cal lesions appear to develop after severe attacks.

Neurology (63)

Fumihiko Hanai: Effect of electrical stimulation of peripheralnerves on neuropathic pain. (Inabe Orthopedic Clinic, Inabe,Japan) Spine 2000;25:1886–1892.

Responses of wide dynamic range neurons in the lumbosacraldorsal horn to input from C fibers were studied in urethanechloralose-anesthetized cats. The posterior tibial nerve and sci-atic nerve were stimulated simultaneously to examine the ef-fect on the C fiber responses elicited by superficial peronealnerve stimulation. Simultaneous stimulation of the posteriortibial nerve and sciatic nerve was performed with superficialperoneal nerve C fiber stimulation. This study demonstratedthat electrical stimulation of peripheral nerves leads to inhibi-tory input to the pain pathways at the spinal cord level.

Neurology (64)

Kenneth Schmader: Herpes zoster in the elderly: issues relatedto geriatrics. (Durham Veterans Affairs medical Center,Durham, NC) Clin Infect Dis 1999;28:736–739.

This article reviews specific clinical and research issues of her-pes zoster related to geriatric medicine. Salient epidemiologicaland clinical issues include the increasing probability of zosterand postherpetic neuralgia with aging, age-related decline inimmunity to varicella-zoster virus, the functional and psycho-social impact of zoster on the quality of life of the elderly, ill-ness behavior in elderly patients with zoster, and varicella-zoster virus transmission and control in the nursing home. Therole of antiviral therapy, corticosteroids, and analgesics; themeasurement and analysis of pain, health-related quality oflife, and functional status; and the development of varicellavaccine in the management of zoster in the elderly are also em-phasized. Fertile research opportunities exist within these ar-eas for investigators interested in infectious diseases, geriatrics,and other zoster-related disciplines.

Neurology (65)

Virginia K. Lee, Lynn Simpkins: Herpes zoster and posther-petic neuralgia in the elderly. (University of Virginia, Char-lottesville, VA) Geriatr Nurs 2000;21:132–136.

This article described herpes zoster (HZ), its causes, diagnosis,treatment, and associated complications. Postherpetic neural-gia (PHN), the most common complication of HZ, is the pri-mary focus of the discussion. PHN is defined broadly aschronic pain that persists after the characteristic vesicular rashof HZ has resolved.

Neurosurgery (66)

Marius A. Kemler, Gerard A.M. Barendse, Maarten van Kleef,et al: Spinal cord stimulation in patients with chronic reflexsympathetic dystrophy. (Maastricht University Hospital, Maas-tricht, The Netherlands) N Engl J Med 2000;343:618–624.


This randomized trial involved patients who had had reflexsympathetic dystrophy for at least 6 months. Thirty-six pa-tients were assigned to receive treatment with spinal cord stim-ulation plus physical therapy, and 18 were assigned to receivephysical therapy alone. The spinal cord stimulator was im-planted only if test stimulation was successful. The intensity ofpain was assessed (on a visual-analogue scale from 0 cm [nopain] to 10 cm [very severe pain]), as well as the global per-ceived effect (on a scale from 1 [worst ever] to 7 [best ever]),functional status, and the health-related quality of life. Thetest stimulation of the spinal cord was successful in 24 pa-tients; the other 12 patients did not receive implanted stimula-tors. In an intention-to-treat analysis, the group assigned to re-ceive spinal cord stimulation plus physical therapy had a meanreduction of 2.4 cm in the intensity of pain at 6 months, ascompared with an increase of 0.2 cm in the group assigned toreceive physical therapy alone (P , 0.001 for comparison be-tween the 2 groups). In addition, the proportion of patientswith a score of 6 (“much improved”) for the global perceivedeffect was much higher in the spinal cord stimulation groupthan in the control group (39% vs. 6%, P 5 0.01). There wasno clinically important improvement in functional status. Thehealth-related quality of life improved only in the 24 patientswho actually underwent implantation of a spinal cord stimula-tor. Six of the 24 patients had complications that required ad-ditional procedures, including removal of the device in 1 pa-tient. Conclude in carefully selected patients with chronicreflex sympathetic dystrophy, electrical stimulation of the spi-nal cord can reduce pain and improve health-related quality oflife.

Conmment by R. Ruiz-López, MD.This is a well-written article describing a prospective, ran-

domized, controlled trial of spinal cord stimulation (SCS) forreflex sympathetic dystrophy, which is also known as complexregional pain syndrome type I (CRPS I). The results showclearly that in carefully selected patients suffering from thispain syndrome, SCS can reduce pain and improve health-related quality of life compared to patients treated only withphysical therapy. Functional status did not improve in eithergroup of patients as SCS treats pain, but not the disease itself.The authors note that the improvement in the overall score forhealth-related quality of life was derived mainly from the alle-viation of pain as in the study population, pain was the pri-mary source of distress. This study represents a major refer-ence for pain doctors and neurosurgeons treating CRPS andchronic pain.

Neurosurgery (67)

Marius A. Kemler, Gerard A.M. Barendse, Maarten vanKleef: Recurrent rejection of a spinal cord stimulation system.(Maastricht University Hospital, Maastricht, The Nether-lands) Contact Dermatitis 2000;42:304–305.

This case report involved a 52-year old male reflex sympa-thetic dystrophy patient. This brief report describes a patientwho responded to spinal cord stimulation positively, but who

could not continue to undergo this treatment because of in-flammatory-type reactions of unknown pathophysiology.

Comment by R. Ruiz-López, MD.This is a case report communication describing a patient

who responded to spinal cord stimulation (SCS) positively, butwho could not continue to undergo this modality because ofinflammatory-type reactions of unknown pathophysiology.Once signs and symptoms of infection with negative bacterio-logical cultures had occurred for 2 consecutive times, the au-thors suspected contact hypersensitivity to materials of theSCS system to be the cause of rejection. Although a very rarecondition, allergic reactions to cardiac pacemakers have previ-ously been reported. In this case, a striking feature was thelack of any visible skin reaction such as rash, erythema, localswelling, or pruritus.

Neurosurgery (68)

John B. Wahlig, William C. Welch, Tracey L. Weigel, JamesD. Luketich: Microinvasive transaxillary thoracoscopic sym-pathectomy: technical note. (Presbyterian University Hospital,Pittsburgh, PA) Neurosurgery 2000;46:1254–1258.

This report describes a two-port transaxillary thoracoscopicapproach for thoracic sympathectomy that maximizes work-ing space, improves manipulative ability, and enhances visual-ization of the surgical field. Positioning of the patients was op-timized to displace the scapula posteriorly, widen the avenueof approach to the sympathetic ganglia, and create a more di-rect route to the target. The semi-Fowler position permittedthe lung apex to fall away from mediastinal structures, obviat-ing a separate retraction port. A 30-degree endoscope allowedan unobstructed view of surgical progress, and anatomic rela-tionships were manipulated in a temporal sequence to facili-tate dissection. Microinvasive transaxillary sympathectomywas performed successfully in 13 patients, all of whom had agood outcome without complications. Conclude the modifica-tions implemented increase the speed and safety of thoraco-scopic sympathectomy while minimizing complications.

Comment by R. Ruiz-López, MD.Thoracic sympathectomy is an accepted means of treating hy-

perhidrosis, Raynaud’s disease, causalgia major and other auto-nomically mediated syndromes. The authors describe a two-porttransaxillary thoracoscopic approach that maximizes workingspace, improves manipulative ability, and enhances visualiza-tion of the surgical field, advocating a lateral decubitus semi-Fowler position. A total of 13 patients were treated, 11 withreflex sympathetic dystrophy (complex regional pain syndrometype I (CRPS I)) and 2 with palmar hyperhidrosis. Interestingly,the authors excellent outcomes for CRPS I, not reflecting theexperience of most practitioners. Thoracoscopic sympathectomyis evolving quickly since first described by Klux in 1951. Froma technical standpoint, the authors describe a useful procedureof endoscopic thoracic sympathectomy that is worthy of fur-ther investigation as the series is limited to only 13 patients andin a larger series come complications would be encountered.


Neurosurgery (69)

Michihiro Kohno, Hiroshi Takakashi, Hiromu Segawa, KeijiSano: Neurovascular decompression for idiopathic tarsal tun-nel syndrome: technical note. (Fuji Brain Institute and Hospi-tal, Fujinomiya City, Shizuoka Prefecture, Japan) J NeurolNeurosurg Psychiatry 2000;69:87–90.

This study evaluates the efficacy of neurovascular decompres-sion for patients with tarsal tunnel syndrome (TTS). Twelvefeet from 9 patients with idiopathic TTS were treated. The pa-tients were aged 52–78 years (mean 64.6 years), and all ofthem complained of pain or dysaesthesia of the sole of thefoot. The posterior tibial nerve was freed from the attached ar-teriovenous complex (posterior tibial artery and veins). Thedissected nerve had a flattened appearance in all of the pa-tients, suggesting nerve compression by the adjacent arterio-venous complex and superficially by the flexor retinaculum. Agraft of fat was inserted as both a cushion and an antiadhesivebetween the vessels and the nerve to achieve neurovascular de-compression. Patients on whom neurovascular decompressionwas performed had resolution or lessening of symptoms intheir feet. Neither wound infection nor recurrence of symp-toms was found during the follow-up period (mean 26.8months). Conclude neurovascular compression syndromeplays a part in idiopathic TTS, and adding neurovascular de-compression to resection of the flexor retinaculum is effective.

Comment by R. Ruiz-López, MD.The surgical outcome of idiopathic tarsal tunnel syndrome

(TTS) has been reported less than ideal and worse than that at-tributable to tarsal coalition tumor or ganglion. The authorsconsidered necessary the development of a new technique inthe surgical treatment of this syndrome assuming that neu-rovascular compression plays a part in idiopathic TTS. Theytreated 12 feet from 9 patients on whom neurovascular de-pression with a graft of fat adding resection to the flexor reti-naculum was effective for the resolution or lessening of painand paresthesia in all cases during a mean follow-up period of26.8 months without complications.

Orthopedics (70)

Chia-Chin Lin: Applying the American Pain Society’s QA stan-dards to evaluate the quality of pain management among sur-gical, oncology, and hospice inpatients in Taiwan. (TaipeiMedical College, Taipei, Taiwan) Pain 2000;87:43–49.

The purpose of this study was two-fold: first, to apply theAmerican Pain Society (APS) outcome questionnaire to exam-ine and compare the quality of pain management provided insurgical, oncology, and hospice inpatient units in the Taipeiarea of Taiwan, and second, to provide baseline data of painmanagement quality in advance of the implementation of na-tional guidelines for cancer pain management. Data revealedthat hospice patients reported that they received pain medica-tion within 15 min after they complained of pain. However, alarge number of patients never asked for pain medication dur-ing hospitalization. Moreover, most patients never requested

medication changes even when their perception was that theirmedication was not effective. The findings of this study mayprovide support for the effectiveness of hospices in Taiwan inpain management and provide information on the validity ofthe APS quality standards.

Orthopedics (71)

Norbert Boos, Norbert Semmer, Achim Elfering: Natural his-tory of individuals with asymptomatic disc abnormalities inmagnetic resonance imaging: predictors of low back pain-related medical consultation and work capacity. (University ofZurich, Zurich, Switzerland) Spine 2000;25:1484–1492.

This prospective study involved 46 asymptomatic individualswho had a high rate of disc herniations (73%) that were ob-served for an average of 5 years. Four classes of variable wereassessed at baseline and follow-up. Disc herniations and neu-ral compromise did not significantly worsen at follow-up,whereas disc degeneration progresses in 17 individuals (41.5%).Minor episodes of low back pain occurred in 19 individuals(41.3%), 6 of whom had to seek medical treatment and 5 ofwhom had to stop work temporarily. The requirement for lowback pain-related medical consultation was predicted withhigh accuracy by listlessness, job satisfaction, and working inshifts (P , 0.001). Work capacity was best predicted by physi-cal job characteristics, job disaffection, and working in shifts(P , 0.001). Conclude that physical job characteristics andpsychological aspects of work were more powerful than mag-netic resonance imaging-identified disc abnormalities in predict-ing the need for low back pain-related medical consultationand the resultant work incapacity. However, the conclusionsare still preliminary, and replication of the findings in largerand more representative study samples is needed.

Orthopedics (72)

Patricia Dolan, Keith Greenfield, Richard J. Nelson, Ian W.Nelson: Can exercise therapy improve the outcome of micro-discectomy? (University of Bristol, Bristol, United Kingdom)Spine 2000;25:1523–1532.

This study determined the effects of a postoperative exerciseprogram on pain, disability, psychological status, and spinalfunction. Twenty patients who underwent lumbar microdis-cectomy were randomized into EXERCISE and CONTROLgroups. After surgery, all patients received normal postopera-tive care that included advice from a physiotherapist about ex-ercise and a return to normal activities. Six weeks after sur-gery, patients in the EXERCISE group undertook a 4-weekexercise program that concentrated on strength and enduranceof the back and abdominal muscles and mobility of the spineand hips. Assessments of spinal function were performed in allpatients during the week before the surgery and at 6, 10, 26,and 52 weeks after. On each occasion, patients completedquestionnaires that asked about pain, disability, and psycho-logical status. Surgery improved pain, disability, back muscleendurance capacity and hip and lumbar mobility in both


groups of patients. After the exercise program, the EXERCISEgroup showed further improvements. The only further im-provement showed by the CONTROL group was an increasein back muscle endurance capacity. Conclude that a 4-weekpostoperative exercise program can improve pain, disabilityand spinal function in patients who undergo microdiscectomy.

Orthopedics (73)

Jason C. Fanuele, Nancy J.O. Birkmeyer, William A. Abdu,Tor D. Tosteson, James N. Weinstein: The impact of spinalproblems on the health status of patients: have we underesti-mated the effect? (Dartmouth-Hitchcock Medical Center, Leb-anon, New Hampshire) Spine 2000;25:1509–1514.

This prospective study involved 17,774 patients who consultedspine centers and aimed to qualify the effect that spinal diag-noses have on patient’s physical functional status (SF-36 Phys-ical Component Summary (PCS) score) compared with othercommon conditions and to qualify the effects of comorbiditieson physical functional status in spine patients. The study pa-tients were a mean of 47.5 years of age, 54.7% were female,52.3% had lumbosacral diagnoses, and 82% has had 3 or moremonths of pain. The population had a mean PCS score of30.4 6 9.95 (SD) compared with 50.0 6 10.00 for the generalUnited States population. The more comorbidities in a patient,the lower the PCS score (Spearman rank correlation 5 20.27).The 5 comorbid conditions that lowered the PCS the most in-cluded congestive heart failure, chronic obstructive pulmonarydisease, renal failure, rheumatoid arthritis, and lupus. Con-clude the PCS score is greatly affected in patients with spinalproblems. The study population’s OCS was lower or similar tothe PCS for patients with other illnesses reported in the litera-ture. Further, the presence of comorbidity in spine patientsadds to the burden of spinal conditions on functional status.

Orthopedics (74)

Llmo Keskimäki, Seppo Seitsalo, Jeikki Österman, Pekka Ris-sanen: Reoperations after lumbar disc surgery: a population-based study of regional and interspecialty variations. (NationalResearch and Development Center for Welfare and Health(STAKES), Helsinki, Finland) Spine 2000;25:1500–1507.

This study aimed to explore rates of reoperation after lumbardisc surgery and their regional and interspecialty variations.Patients who underwent lumbar spine surgery from 1987 to1995 were identified in the Finnish Hospital Discharge Regis-ter. Data on the patient’s initial disc operations, subsequentoperations, and cause-of-death records were linked using per-sonal identification codes. The Kaplan-Meier method andproportional hazard model were used to analyze risks of reop-eration after initial surgery and for neurosurgical and orthope-dic patients of university hospitals. Out of 25,359 surgicalpatients with herniated lumbar discs, 12.3% underwent subse-quent lumbar operations corresponding to the cumulative risk of18.9% in the 9-year follow-up. Reoperation rates increased dur-ing the study period with the recent patient cohorts exhibiting

risks. The reoperation risk showed a systematic geographicvariation: the higher the regional disc surgery rate, the higherthe reoperation risk. Overall, neurosurgical patients had ahigher reoperation risk than orthopedic patients, but it wasnot a uniform finding. Conclude that the reoperation risk afterdisc surgery increased during the study period and was higherin hospital catchment areas with higher overall discectomyrates. The reoperation rates varied among the university hospi-tals, but tended to be higher for neurosurgical rather than fororthopedic patients.

Orthopedics (75)

Mohammed BenDebba, Warren S. Torgerson, Donlin M.Long: A validated, practical classification procedure for manypersistent low back pain patients. (Johns Hopkins School ofMedicine, Baltimore, MD) Pain 2000;87:89–97.

This article discussed the development of a simple procedurefor assigning persistent low back pain (LBP) patients to 1 of 4mutually exclusive, hierarchically organized classes. This pro-cedure relies on the spatial distribution of a patient’s pain andthe results of straight leg raise tests to make the assignment.The procedure was applied to a large group of patients whosought treatment for persistent LBP at several university affili-ated tertiary care clinics, and found that the resulting 4 classesof patients were significantly different from one another intheir presentation, and in the way they were evaluated andtreated by physicians. Conclude that the procedure may havepractical research and clinical applications.

Orthopedics (76)

James D. Kang, Henry H. Bohlman: Cervical disc herniation ina patient with congenital insensitivity to pain: a case report.(University of Pittsburg Medical center, Pittsburg, PA) Spine2000;25:1726–1728.

This report discussed the clinical manifestations and the treat-ment outcome of a patient with a known diagnosis of congenitalinsensitivity to pain who developed a herniated cervical disc. Thepatient had neurologic motor weakness with “neck and shoulderpain.” A clear radicular pattern could not be elicited. The patientunderwent a successful anterior discectomy and fusion with long-term clinical and radiographic results. Conclude that patientswith congenital insensitivity to pain who develop a cervical discherniation may present with atypical symptoms not manifestingin the classic radicular pattern. Higher index of suspicion by theclinician must be practiced to make the appropriate diagnosis.Successful surgical outcome may be achieved in these patients.

Orthopedics (77)

Eugene J. Carragee, Yung Chen, Cary M. Tanner, Chris Hay-ward, Michael Rossi, Chad Hagle: Can discography cause long-term back symptoms in previously asymptomatic subjects?(Stanford University School of Medicine, Stanford, CA) Spine2000;25:1803–1808.


This prospective controlled study aimed to determine whetherdiscography might cause long-term low back symptoms in se-lected patients. Twenty-six patients without preexisting lowback pain were observed for 1 year after lumbar discographyto determine the effects of lumbar discography in 3 experimen-tal groups: 10 patients who had remote cervical spine surgerywith excellent results (pain-free group); 10 patients who hadthe same surgery with poor results (chronic pain group); and 6patients who had primary somatization disorders. Two con-trol groups were also observed: a group of patients with soma-tization disorder who were similarly evaluated but withoutdiscography and a group of patients with low back pain ob-served for 1 year after discography without surgery. In the 3experimental groups (no back pain before discography) nosubject with normal psychometric testing had persistent painafter discography (0/11), whereas 6 (40%) of the 15 with ab-normal psychometric tests results reported significant new lowback pain. None of the pain-free group (0/10), 20% of thechronic neck pain group (2/10), and 66% of the somatizationgroup (4/6) continued to have significant back pain 1 year af-ter injection. Psychological testing and occupational disabilitystrongly predicted continued pain after discography. The con-trol groups had no significant change in low back symptoma-tology during the year of observation. Conclude that discogra-phy in a subject group without low back pain, but withsignificant emotional and chronic pain problems may result inreports of significant back pain for at least 1 year after injec-tion. Subjects with normal psychometric test results had no re-ports of significant long-term back pain after discography.

Pediatrics (78)

Minna Aromaa, Matti Sillanpää, Päivi Rautava, Hans Hele-nius: Pain experience of children with headache and their fam-ilies: a controlled study. (University of Turku, Turku, Finland)Pediatrics 2000;106:270–275.

This study reported the pain sensitivity of children with head-ache and their family members as well as the prevalence of re-curring aches, psychosocial life, and family environment ofchildren with headache at preschool age. A representative pop-ulation-based sample of 1443 families expecting their firstchild was followed over 7 years. A screening questionnaire re-lating to the child’s headache was sent to parents of a represen-tative sample of 1132 6-year-old children. Of 144 children suf-fering from headache, 106 (76%) were examined and interviewedclinically. Ninety-six children (58 migraine and 38 tension-typeheadache children) with primary headache and matched controlswere included in further examinations. Children with head-ache were more often extremely sensitive to pain accordingto their parents, were more excited about physical examina-tions, cried more often during blood sampling or vaccination,avoided play or games more often because they were afraid ofhurting themselves, and had recurring abdominal and growingpains more often than did control children. The fathers of chil-dren with headache were more often extremely sensitive topain. Children with headache reacted with somatic symptoms,usually with pain and functional intestinal disorders in stresssituations, felt more tired, and had more ideations of death

during the previous month. More mothers of tension-typeheadache children than those of migraine children reportedthat they were considerably sensitive to pain. Tension-typeheadache children had a poorer family environment; the fam-ily atmosphere was more often unhappy and the relationshipbetween parents was more often distant than in families ofchildren with migraines. Conclude that in addition to somaticfactors, it is important to consider the child’s pain sensitivity,reaction to various stress situations, and family functioningwhen studying childhood headache. The child’s coping mecha-nisms can be supported by information given by the parents.School entry can be considered a suitable period for careful in-vestigation into possible occurrence of headache and also forgiving information about headache and its management

Pediatrics (79)

Christel W. Perquin, Alice A.J.M. Hazebroek-Kampschreur,Joke A.M. Hunfeld et al: Pain children: a common experience.(Erasmus University Rotterdam, Rotterdam, The Netherlands)Pain 2000;87:51–57.

This study analyzed the prevalence of pain in Dutch childrenfrom 0 to 18 years of age. A random sample of 1300 children0–3 years of age was taken from the register of population inRotterdam, The Netherlands. In the Rotterdam area, 27 pri-mary schools and 14 secondary schools were selected to obtaina representative sample of 5336 children from 4–18 years of age.Depending on the age of the child, a questionnaire was eithermailed to the parents (0–3 years) or distributed at school (4–18years). Of 6636 children surveyed, 5424 (82%) responded; re-sponse rates ranged from 64% to 92%, depending on the sub-ject age and who completed the questionnaire. Of the respon-dents, 54% had experienced pain within the previous 3 months.Overall, a quarter of the respondents reported chronic pain (re-current or continuous pain for more than 3 months). The prev-alence of chronic pain increased with age, and was significantlyhigher in girls (P , 0.001). In girls, a marked increase occurredin reporting chronic pain between 12 and 14 years of age. Themost common types of pain in children were limb pain, head-ache, and abdominal pain. Half of the respondents who hadreported pain reported to have multiple pain, and one-third of thechronic pain sufferers experienced frequent and intense pain.These multiple pains and severe pains were more often reportedby girls (P , 0.001). The intensity of pain was higher in thecase of chronic pain (P , 0.001) and multiple pains (P , 0.001),and for chronic pain the intensity was higher for girls (P ,0.001). These findings indicate that chronic pain is a commoncomplaint in childhood and adolescence. In particular, the highprevalence of severe chronic pain and multiple pain in girls aged12 years and over calls for follow-up investigations document-ing the various bio-psycho-social factors related to this pain.

Pediatrics (80)

J.M. Wilson, R. Wise, M.D. Klein et al: Palliative care for chil-dren. (American Academy of Pediatrics, Elk Grove Village, IL)Pediatrics 2000;106:351–357.


This article presented an integrated model for providing pallia-tive care for children living with a life-threatening or terminalcondition. Advice on the development of a palliative care planand on working with parents and children is also provided.Barriers to the provision of effective pediatric palliative careand potential solutions are identified. The American Academyof Pediatrics recommends the development and broad avail-ability of pediatric palliative care services based on child-specific guidelines and standards. Such services will requirewidely distributed and effective palliative care education of pe-diatric health care professionals. The Academy offers guidanceon responding to requests for hastening death, but does notsupport the practice of physician-assisted suicide or euthanasiaof children.

Pharmacology (81)

Roger Abs, Johan Verhelst, Jan Maeyaert et al: Endocrine con-sequences of long-term intrathecal administration of opioids.(University of Antwerp, Edegem, Belgium) J Clin EndocrinolMetab 2000;85:2215–2222.

This study involved 73 patients (29 men and 44 women) re-ceiving opioids intrathecally for nonmalignant pain whowere enrolled for extensive endocrine investigation. At thetime of hormonal determination, the mean duration of opi-oid treatment was 26.6 6 16.3 months; the mean daily dose ofmorphine was 4.8 6 3.2 mg. The control group consisted of20 patients (11 men and 9 women) with a comparable painsyndrome, but not treated with opioids. Decreased libidoor impotency was present in 23 of 24 men receiving opioids.The serum testosterone level was below 9 nmol/L in 25 of29 men and was significantly lower than that in the controlgroup (P , 0.001). The free androgen index was below nor-mal in 18 of 29 men and was significantly lower than that inthe control group (P , 0.001). The serum LH level was lessthan 2 U/L in 20 of 29 men and was significantly lower thanthat in the control group (P , 0.001). Serum FSH was com-parable in both groups. Decreased libido was present in 22 of32 women receiving opioids. All 21 premenopausal femalesdeveloped either amenorrhea or an irregular menstrual cycle,with ovulation in only 1. Serum LH, estradiol, and progester-one levels were lower in the opioid group. In all 18 postmeno-pausal females significantly decreased serum LH (P , 0.001)and FSH (P 5 0.012) levels were found. The 24-h urinaryfree cortisol excretion was below 20 mg/day in 14 of 71 opioidpatients and was significantly lower than that in the controlgroup (P 5 0.003). The peak cortisol response to insulin-induced hypoglycemia was below 180 mg/L in 9 of 61 opioidpatients and was significantly lower than that in the nonopi-oid group (P 5 0.002). The insulin-like growth factor I sdscore was below 22 sd in 12 of 73 opioid patients and wassignificantly lower than that in the control group (P 50.002). The peak GH response to hypoglycemia was below3 mg/L in 9 of 62 subjects and was significantly lower thanthat in the control group (P 5 0.010). Thyroid function testsand PRL levels were considered normal. No metabolic distur-bances were recorded, apart from significantly decreased high-

density lipoprotein cholesterol levels (P 5 0.041) and elevatedtotal/high density lipoprotein cholesterol ratio (P 5 0.008) inthe opioid group compared to the control group. Supple-mentation with gonadal steroids improved sexual function inmost patients. Conclude of all patients receiving intrathecalopioids, the large majority of men and all women developedhypogonadotropic hypogonadism, about 15% developedcentral hypocorticism, and about 15% developed GH defi-ciency. These findings suggest that further investigations arerequired to determine the need for systematic endocrinework-up in these patients and the necessity for substitutivetherapy.

Pharmacology (82)

Klaus Eckhardt, Susanne Ammon, Ute Hofmann, Anja Riebe,Nadja Gugeler, Gerd Mikus: Gabapentin enhances the analge-sic effect of morphine in healthy volunteers. (Dr. MargareteFischer Bosch Institut fuer Klinische Pharmakologie, Stuttgart,Germany) Anesth Analg 2000;91:185–191.

This randomized, placebo-controlled, double-blinded studyinvestigated the pharmacodynamic and pharmacokinetic in-teraction of Gabapentin (GBP) and morphine in 12 healthymale volunteers. Morphine (60 mg, controlled release) or pla-cebo was administered at 8:00 a.m., and GBP (600 mg) or pla-cebo was administered at 10:00 a.m., thus comparing the anal-gesic effect of placebo 1 GBP (600 mg) with placebo 1placebo and morphine (60 mg) 1 GBP in comparison to mor-phine plus placebo by using the cold pressor test. The durationand intensity of the side effects were assessed by using visualanalog scales. The analgesic effect was evaluated by the changein the area under the curve of pain tolerance. Placebo 1 GBPdid not present any significant analgesic effect compared withplacebo 1 placebo. A siginificant increase in pain tolerancewas observed comparing the combination of morphine andGBP with morphine and placebo. The observed adverse eventsafter placebo 1 GBP were not significantly different comparedwith placebo 1 placebo. Morphine 1 placebo led to the ex-pected opioid-mediated side effects. They were significantlymore pronounced compared with placebo 1 placebo, but didnot differ significantly compared with the combination ofmorphine 1 GBP. Concerning the pharmacokinetic variablesof morphine and its glucuronides, no significant difference be-tween morphine 1 placebo and morphine 1 GBP was ob-served, whereas the area under the curve of GBP significantlyincreased, and apparent oral clearance and apparent renalclearance of GBP decreased when morphine was administeredconcomitantly. These results suggest 2 different sites for thepharmacokinetic interaction—1 at the level of absoption andthe other at the level of elimination. The study reveals both apharmacodynamic and pharmacokinetic interaction betweenmorphine and GBP, leading to an increased analgesic effect ofmorphine 1 GBP. These results and the good tolerability ofGBP should favor clinical trials investigating the clinical rele-vance of the combination of morphine and GBP for treatingsevere pain.


Pharmacology (83)

P.M. Warren, J.H. Taylor, K.E. Nicholson, P.K. Wraith, G.B.Drummond: Influence of tramadol on the ventilatory responseto hypoxia in humans. (University of Edinburgh, Edinburgh,United Kingdom) Br J Anaesth 2000;85:211–216.

In this study, the effect of tramadol on the ventilatory responseto 7 min acute isocapnic hypoxia during steady mild hypercap-nia in 14 healthy volunteers (7 male, 7 female) was studied.The acute hypoxic response was measured before and 1 h afteroral placebo or tramadol (100 mg). After tramadol, ventila-tion during mild hypercapnia (mean 11.28 liters min21) wassignificantly less (P , 0.05) than during placebo baseline(13.93 liters min21), tramadol baseline (14.63 liters min21),or after placebo (14.9 liters min21), confirming that tramadolhas a small depressive effect on the hypercapnic ventilatory re-sponse. There was no significant difference in the hypoxic ven-tilation/Spo2 response measured during the placebo baseline(0.99), placebo (1.18), tramadol baseline (0.78) or tramadol(0.68) runs. These data suggest that tramadol does not depressthe hypoxic ventilatory response.

Physical Medicine and Rehabilitation (84)

Yoon-Kyoo Kang, Eun-Ha Lee, Miriam Hwang: Pure trigeminalmotor neuropathy: a case report. (Korea University Medical Cen-ter, Guro-gu, Korea) Arch Phys Med Rehabil 2000;81:995–998.

A 38-year-old man complaining of progressive weakness andwasting of the right masticatory muscles after a bout of mild coldsymptoms is presented in this case report. No sensory symptomswere present. History, neurologic examination, electrophysio-logic studies, and magnetic resonance imaging of the brain ledto the diagnosis of pure trigeminal motor neuropathy. The causemay have been an autoimmune reaction to a viral infection.

Comment by Miles Day, MD.This article is a case report of pure trigeminal motor neu-

ropathy. Trigeminal motor neuropathy is defined as a trigemi-nal motor paralysis accompanied by no trigeminal sensorysigns or other cranial nerve involvement. The author describedthe history of the patient and their work up including exami-nation, laboratory tests, and electro diagnostic examinations,which all pointed to the pure trigeminal motor neuropathy.The strength of this case report is the detailed description ofthe anatomy of the trigeminal nerve and the muscular innerva-tions of the mandubular branch. The authors attributed themotor neuropathy to a possible post viral infection autoim-mune response that predominantly affected the motor divisionof the trigeminal nerve. They have stressed that all other po-tential causes of motor neuropathy should be ruled out includ-ing malignancy in mass lesions.


Erbil Dursun, Nigar Dursun, Canan Eksi Ural, Aytül Çakci: Gle-nohumeral joint subluxation and reflex sympathetic dystrophy

in hemiplegic patients. (Kocaeli University, Kocaeli, Turkey)Arch Phys Med Rehabil 1999; 81:944–946.

This is a case-controlled study of the relationship between gle-nohumeral joint subluxation and reflex sympathetic dystrophy(RSD) in hemiplegic patients set in an inpatient rehabilitationhospital. Thirty-five hemiplegic patients with RSD (RSD group)and 35 hemiplegic patients without RSD (non-RSD group) wereincluded in this study. Patients with rotator cuff rupture, bra-chial plexus injury, or spasticity greater than stage 2 on theAshworth scale were excluded. Both the RSD and non-RSDgroups were assessed for presence and grade of subluxationfrom radiographs using a 5-point categorization. The degreeof shoulder pain of the non-RSD group was assessed by a vi-sual analogue scale of 10 points. Glenohumeral subluxationwas found in 74.3% of the RSD group and 40% of the non-RSD group (P 5 0.004). In the non-RSD group, 78.6% of thepatients with subluxation and 38.1% of the patients withoutsubluxation reported shoulder pain (P 5 0.019). No correla-tion was found between the degree of shoulder pain and gradeof subluxation in the non-RSD group (P 5 0.152). Concludethat the findings suggest that shoulder subluxation may be acausative factor for RSD. Therefore, prevention and appropri-ate treatment of glenohumeral joint subluxation should be in-cluded in rehabilitation of hemiplegic patients.

Comment by Miles Day, MD.The purpose of this study was to examine the relationship

between shoulder subluxation in hemiplegic patients and re-flex sympathetic dystrophy. They also examined if sublux-ation is associated with shoulder pain and the grade of sublux-ation in patients with subluxation and no reflex sympatheticdystrophy (RSD). Patients with injuries to the rotator cuff ofthe brachial plexus, marked spasticity, and major trauma tojoint structures were excluded as these can be precipitatingfactors for RSD. The study noted a significantly higher pres-ence of shoulder subluxation within the RSD group and thepresence of pain was significantly high in patients with shoul-der subluxation in the non-RSD group. The take home mes-sage of this article is that any measure or treatment that can beapplied to the glenohumeral joint should be performed toeliminate the possibility of the patient developing RSD andsubsequently hindering further rehabilitation in these patients.


David D. Kilmer, Susan G. Aitkens, Nancy C. Wright, MeganA. McCrory: Simulated work performance tasks in personswith neuropathic and myopathic weakness. (University of Cal-ifornia, Sacramento, CA) Arch Phys Med Rehabil 2000;81:938–943.

This study aimed to determine the test-retest reliability of se-lected simulated work performance tasks in persons with neu-ropathic and myopathic weakness and control subjects, andthe association between muscular performance during thesework tasks and conventional isolated muscle group testing.Measurement of 3 tasks was performed on a work simulation


device on 2 different days separated by 1 week. Associationsbetween work task performance and previously reportedstrength measures in 6 muscle groups by hand-held dynamom-etry (HHD) were examined. This study was conducted in thehuman performance laboratory of a university and consistedof a convenience sample of ambulatory outpatients with he-reditary motor and sensory neuropathy, type I (n 5 9), myo-tonic muscular dystrophy (n 5 10), and able-bodied controls(n 5 11). Mean between-session differences for work simula-tion tasks ranged from 211% to 14% for peak torque andfrom 212% to 112% for total work; test sessions did not dif-fer significantly for either patient or control groups. All groupshad between-session intraclass correlation coefficients usually.0.80, which indicated good consistency. In general, correla-tions between peak torque during work simulation and HHDwere strongest in the control group. Conclude that personswith neuromuscular weakness reliably performed the simu-lated work tasks examined in this investigation. Work simula-tion tasks may be a useful tool to assess muscular performancein persons with neuromuscular weakness.

Comment by Miles Day, MD.This article addresses something that is very important

when evaluating patient progress during rehabilitation. It iscommon in rehab to evaluate muscle groups and to determinea muscular performance by using isolated muscle group test-ing. The problem with this is that it doesn’t necessarily corre-late with tasks that patients perform on a day-to-day basis.The purpose of the study was to determine the test-retest reli-ability of selected simulated work performance tasks in pa-tients with neuropathic and myopathic weakness and controlsubjects and the association between muscular performanceduring these work tasks and conventional isolated musclegroup testing. The work simulation tasks included knob-turn-ing (alternating pronation and supination), linear motion (al-ternating push/pull motion), and lever arm (push-down mo-tion). This study did accomplish its goals. The peak torque andtotal work measured in work simulation tasks did not differsignificantly between test and retest sessions for either the pa-tients with neuropathic and myopathic weakness or the con-trol groups.

This study addresses an issue that other studies have not. Justbecause a patient shows improvement in strength measure byhand held dynamometry does not necessarily mean that he orshe will be able to accomplish tasks that are performed at home.The main goal of rehabilitation is for patients to be able to per-form activities of daily living around the house and at work. Ifthis is not accomplished then their rehabilitation is for naught.


A.J. Haig, K. Yamakawa, D.M. Hudson: Paraspinal electromyo-graphy in high lumbar and thoracic lesions. (University of Michi-gan, Ann Arbor, MI) Am J Phys Med Rehabil 2000;79:336–342.

This study aimed to use needle electromyography in theparaspinal muscles to localize the root level of a radiculopa-thy. Nine cases of clinically proven, isolated high lumbar or

thoracic disk herniations of patients who underwent MiniPMwere collected. Four were from a prospective study of 114 per-sons with low back pain (MiniPM had 100% sensitivity tomagnetic resonance imaging-documented high disks). In themost medial “S” column, mean MiniPM scores were 0.7 forthe level above the radiologically documented lesion (3.1 atthe lesion and 1.6, 1.6, and 1.1 at the 3 spinous processes be-low the lesion). Similar numbers were obtained in the “M”column (slightly lateral), with no significant differences be-tween S and M. Differences were significant between and atthe level of the lesion for S (P , 0.06) and M (P , 0.01), andbetween the lesion level and 3 levels below for the M column(P , 0.01). Conclude that paraspinal electromyography has ahigher than previously reported sensitivity for high lumbar le-sions. Electromyography using MiniPM can localize some ra-diculopathies. The individual cases suggest that, consistentwith the anatomy of the caudi equina, thoracic lesions and lat-eral lumbar lesions denervate only at 1 level, but more centrallumbar lesions also denervate distally innervated paraspinalmuscles.

Comment by Miles Day, MD.This study is designed to assess the sensitivity of many

MiniPM for higher-level rediculopathies, ie, lower thoracicand high lumbar, and to determine if findings are specific tothe root level involved. The MiniPM is thought to assess themultifidus portion of the paraspinal muscles that are inner-vated from L2 to the sacrum. The clinical protocol tests theparaspinal extensively and provides a numerica score, thuseliminating some subjectivity of the EMG. The study demon-strates that MiniPM has good sensitivity for high lumbar andthoracic lesions and provides information on the level of thelesion independent of limb EMG. After reviewing the study, Iagree with the authors that MiniPM is in itself not diagnosticfor radiculopathy, but is only an additional test to help sup-port other neuro physiological studies when evaluating for ra-diculopathy. It is not specific for diagnosing radiculopathy.


A. Suputtitada: Managing spasticity in pediatric cerebral palsyusing a very low dose of botulinum toxin type A: preliminaryreport. (Chulalongkorn University Hospital, Bangkok, Thai-land) Am J Phys Med Rehabil 2000;79:320–326.

This study was conducted to determine if very low doses ofbotulinum toxin type A (BTX-A) could reduce spasticity andimprove gait in cerebral palsied children when combined withrehabilitation therapy. The trainable (IQ . 80), ambulatory,spastic diplegic or hemiplegic cerebral palsied children, withno fixed contractures in at least one limb, were selected for thisstudy. Patients with a score of 3 on a modified Ashworth scalereceived 0.5 units of BTX-A/kg/muscle. Patients with an Ash-worth score of 4 received 1.0 BTX-A/kg/muscle. After BTX-Ainjection, all patients received rehabilitation therapy and plas-tic ankle and foot orthoses for walking. Both groups exhibitedimprovement in Ashworth score and in gait within 72 h of in-


jection with botulinum toxin. Beneficial effects persisted for10 to 12 months in most patients, with 3 patients exhibitingbenefits for at least 20 months. Conclude that a very low doseof BTX-A combined with rehabilitation therapy resulted in along-lasting decrease in spasticity and an improvement in gaitin children with cerebral palsy.


Curtis W. Slipman, Jason S. Lipetz, Richard J. Herzog, Ed-ward J. Vresilovic: Nonsurgical treatment for radicular pain ofzygoapophyseal joint cyst origin: therapeutic selective nerveroot block. (Hospital of the University of Pennsylvania, Phila-delphia, PA) Arch Phys Med Rehabil 2000;81;1119–1122.

This report discusses the first case of zygoapophyseal jointcyst-induced radicular pain successfully treated with therapeu-tic selective nerve root block. A 56-year-old dentist presentedwith pain involving the lateral thigh, lateral calf, and foot dor-sum that worsened with standing and walking. Magnetic reso-nance imaging of the lumbar spine showed a cyst emanatingfrom the right L4-L5 zygoapophyseal joint, resulting in centralcanal and lateral recess stenosis. The patient was treated with2 fluoroscopically guided therapeutic L5 selective nerve rootblocks. The patient remained pain free at 18-month follow-up.


Kenneth P. Botwin, Robert D. Gruber, Constantine G.Bouchlas, Francisco M. Torres-Ramos, Ted L. Freeman, War-ren K. Slaten: Complications of fluoroscopically guided trans-formational lumbar epidural injections. (Florida Spine Insti-tute, Clearwater, FL) Arch Phys Med Rehabil 2000;81:1045–1050.

This retrospective cohort design study assessed the incidenceof complications of fluoroscopically guided lumbar transfor-mational epidural injections at a multidisciplinary spine carecenter. Patients presenting with radiculopathy caused by eitherlumbar spinal stenosis or herniated nucleus pulposus con-firmed by magnetic resonance imaging or computed tomogra-phy scanning received transformational epidural steroid injec-tions as part of a conservative care treatment plan. Allinjections were performed consecutively over a 4-month pe-riod by 5 physiatrists. An independent observer reviewed med-ical charts, which included a 24-h postprocedure telephonecall by an ambulatory surgery center nurse who had askedquestions from a standardized questionnaire about complica-tions following the injections. Physician follow-up office notes1 to 3 weeks after the injection, along with epiduragrams,were also reviewed. Two hundred seven patients who received322 injections were reviewed. Complications per injectionseen included 10 transient nonpositional headaches that re-solved within 24 h (3.1%), 8 increased back pain (2.4%), 2 in-creased leg pain (0.6%) 4 facial flushing (1.2%), 1 vasovagalreaction (0.3%), 1 increased blood sugar (258 mg/dL) in an in-sulin-dependant diabetic (0.3%), and 1 intraoperative hyper-tension (0.3%). No dural punctures occurred. Conclude there

were no major complications. The incidence of minor compli-cation was 9.5% per injection. All reactions resolved withoutmorbidity, and no patient required hospitalization.


Wannapha Petchkrua, Stacy A. Harris: Shoulder pain as anunusual presentation of pneumonia in a stroke patient: a casereport. (University of Chicago Hospitals, Chicago, IL) ArchMed Phys Rehabil 2000;81:827–829.

An 89-year-old woman with right hemiparesis secondary to is-chemic lacunar infarction who developed sudden onset ofright shoulder pain on the fifth day of inpatient rehabilitationis discussed in this case study. The pain was severe, limitingrange of motion (ROM) and participation in therapy. Exten-sive investigations to rule out subluxation, fracture, connectivetissue disease, RSD, and pulmonary embolism were negative.Ultimately, her shoulder pain and decreased ROM completelyresolved with antibiotic treatment for right lower lobe pneu-monia. Conclude that her symptoms were possibly referredpain from diaphragmatic irritation transmitted via right C4sensory axons in the phrenic nerve, which shares the same der-matome as the right acromion area. This case was an unusualpresentation of pneumonia in an elderly woman with hemiple-gia. The authors recommend that pneumonia be considered indifferential diagnoses of shoulder pain.

Physical Therapy (92)

Jeanine Yip Menck, Susan Mais Requejo, Kornelia Kulig:Thoracic spine dysfunction in upper extremity complex regionalpain syndrome type 1. (University of Southern California, LosAngeles, CA) J Orthop Sports Phys Ther 2000;30:401–409.

The objective of this case study was to demonstrate the impor-tance of assessment and treatment of the thoracic spine in themanagement of a patient with signs and symptoms of upperextremity complex regional pain syndrome type I. The patientwas a 38-year-old woman who suffered a traumatic injury toher left hand. Five months after the injury, she presented withsevere pain, immobility of the left arm, and associated dystro-phic changes. She was unable to work and needed help in someactivities of daily living. The patient was treated for 3 monthsin 36 visits. Initial treatment consisted of cutaneous desensiti-zation, edema management, and gentle therapeutic exercises.However, further examination indicated hypomobility and hy-persensitivity of the upper thoracic spine. Joint manipulationof the T3 and T4 segments was implemented. The patient’sstatus was monitored. Immediately after the vertebral manipu-lation, there was significant increase in the left hand’s skintemperature and a decrease in hyperhydrosis as measured bypalpation. Shoulder range of motion increased from 135º to1758 and the patient reported reduced pain. The decrease inthe patient’s dystrophic and allodynic symptoms permittedfurther progress in functional reeducation. The patient wasdischarged with full return to independence and initiation of a


vocational training program. Conclude that the assessmentand treatment of the thoracic spine should be considered in pa-tients with upper extremity complex regional pain syndrometype I.

Comment by Karen Crawford, RPT.This is a study demonstrating the importance of assessment

of the thoracic spine to manage patients with signs and symp-toms of upper extremity complex regional pain syndrome typeI (CRPS-I). The patient was a 38-year-old female with trau-matic injury to the left hand. The purpose of this study is to de-termine the relation between distal symptoms of CRPS-I andthe thoracic spine and to describe the use of thoracic spine ma-nipulation in the management of patients with CRPS-I in theupper extremity. CRPS-I in the upper extremity often exhibitspostural deviations associated with protective positioning ofthe arm. It emanates as trunk motion during upper activitiesand may present with decreased thoracic intervertebral mobil-ity. This study believes that the evaluation and treatment in ar-eas proximal to a patient’s symptoms in CRPS-I may be neces-sary. Hypomobility secondary to abnormal posturing andanatomical proximity of the sympathetic ganglions to the tho-racic spine may contribute to the link between upper quadrantCRPS-I and thoracic joint dysfunction.

In the study, a 38-year-old, left-hand dominant, femalewho sustained trauma to her left wrist and hand while at workwas seen in physical therapy for a total of 36 visits. Initialtreatment consisted of desensitization, edema management,and general therapeutic exercises. Further examination indi-cated hypomobility and hypersensitivity of the upper thoracicspine. At that time, joint manipulation of T3 and T4 segmentswas implemented. The patient’s status was monitored andrange of motion, strength, temperature, and skin moisturewere measured. The patient reported minimal changes in herstatus, and 1 month into treatments, she hit her left hand on adoor and consequently discontinued therapy because of in-creased pain. Five months after the initial injury, patient wasreevaluated. She then received physical therapy 3 times perweek for 12 weeks and was discharged with significant im-proved functional status. At the initial examination, the diag-nosis of CRPS-I was based on the IASP Committee on Taxon-omy. The initial treatment objective was pain managementand edema control. The long-term goal was return to a func-tional status. Initial treatment consisted of gentle active andpassive wrist and finger range of motion and tubagrip foredema management. A home program desensitization was im-plemented. The patient’s active participation in therapy waslimited secondary to her willingness to move her left arm.Treatment 2 included evaluation and manipulation of the up-per thoracic spine. Her clinician used her manipulating handas a fulcrum by placing it under the supine patient at the levelof thoracic joint dysfunction. A thrust was delivered throughthe patient’s folded arms as she exhaled and there as an audi-ble click. There was an immediate normalization of skin tem-perature, color, as well as significantly decreased allodynic re-sponse to light touch along the left arm and the left upperthoracic vertebral column. Segmental thoracic mobility wasimmediately improved and there was immediate increase inshoulder flexion after this treatment. This reduction of signs

and symptoms of CRPS-I made it possible to proceed withfunctional rehabilitation.

Manipulation of the thoracic spine may have resulted inimprovements in distal upper extremity pain, skin color, andtemperature in a patient with CRPS-I. One explanation is thatdisuse of the arm and abnormal posturing may contribute tothoracic hypomobility. The anatomic proximity of the sympa-thetic chain to the dysfunctional thoracic joints may predis-pose the ganglions to mechanical pressure. Therefore, it is con-cluded that the evaluation and treatment of areas proximal tothe patient’s symptoms are necessary. It is difficult to identifythe mechanism responsible for changing distal symptoms afterthoracic manipulation. The immediate increase in shoulderflexion after manipulation is likely due to mechanical changein the tissue.

In conclusion, this study describes a link between the tho-racic spine and distal symptoms in patients with CRPS-I. Tho-racic joint manipulation appeared to improve spinal mobility,and also appeared to relieve distal and autonomic symptoms.These improvements allowed for functional rehabilitation ofthe effected arm. Therefore, it is the opinion of the study thatthe mobility of the thoracic spine should be evaluated for pa-tients with autonomic dysfunction diagnosed with CRPS-I.The research also indicates a need for further research to de-fine the relationship between neurogenic symptoms and mus-culoskeletal pathology.


Helen Razmjou, John F. Kramer, Riki Yamada: Intertester re-liability of the McKenzie evaluation in assessing patients withmechanical low back pain. (Sunny Brook & Women’s CollegeHealth Sciences Centre, Toronto, Ontario, Canada) J OrthopSports Phys Ther 2000;30:368–389.

In this study, patients were assessed simultaneously by 2 phys-ical therapists trained in the McKenzie evaluation system. Thetherapists were randomly assigned as examiner and observer.Agreement was estimated by Kappa statistics. Forty-five sub-jects (47 6 14 years), composed of 25 women and 20 menwith acute, subacute, or chronic low back pain were exam-ined. The agreement between raters for selection of the Mc-Kenzie syndromes was K 5 0.70, and for the derangementsubsyndromes was K 5 0.96. Interrater agreement for thepresence of lateral shift, relevance of lateral shift, relevance oflateral component, and deformity in the sagittal plane wasK 5 0.52, 0.85, 0.95, and 1.00, respectively. Intertester agree-ment on syndrome categories in 17 patients under 55 years ofage was excellent with K 5 1.00. Conclude that a form of lowback evaluation, using patterns of pain response to repeatedend range spinal test movements, was highly reliable whenperformed by 2 properly trained physical therapists.

Comment by Karen Crawford, RPT.This article intends to address the ability for therapists to

agree on a low back pain diagnosis using the McKenzie tech-nique of classification. It is important for this study to select aclear clinical diagnosis in order to establish rationale for pa-


tient management and determine a prognosis. Another pur-pose for this study was to agree on the relevance of sagittal andfrontal plane deformities using McKenzie methods in assessingpatients with back pain. The subjects included adult patientswith a history of acute, subacute, or chronic low back pain.Patients were referred by general practitioners or specialistsfor treatment at an outpatient department where the study wasconducted. The examination consisted of taking a history, ob-servational evaluation of the range of motion, and completionof a specified tests movements in the sagittal, frontal, and com-bined planes. Subjects were allowed to communicate only withthe assessor. A total of 46 patients with a history of low backpain agreed to complete the assessment. Patients were dividedinto 2 groups, those 55 years of age and older and those youngerthan 55. McKenzie identifies only 3 mechanical syndromes: 1.Postural, 2. Dysfunction, 3. Derangement. Each of these syn-dromes were divided into separate subsyndromes according tolocation of the pain and presence or absence of spinal deformi-ties. The study concluded that therapists trained in use of theMcKenzie evaluation system can be highly reliable in reachingthe same conclusion in respect to classifying patients into diag-nostic syndromes and subsyndromes, especially in patients un-der the age of 55. In contrast to other published studies, theimportance of advanced training for interpretation of symptombehavior definitely leads to selection of the correct diagnosis.


Harriet Wittink, Theresa Hoskins Michel, Ronald Kulich etal: Aerobic fitness testing in patients with chronic low backpain—Which is the best test? (New England Medical Center,Boston, MA) Spine 2000;25:1704–1710.

In this study, 30 participants with chronic low back pain per-formed three symptom-limited maximal exercise tests: a tread-mill, an upper extremity ergometer, and a bicycle ergometer.The tests were administered in randomized order. Heart ratewas continuously monitored and oxygen consumption interms of mL/kg/minute was measured by indirect calorimetryeach 30 seconds. The statistical difference among the tests washighly significant (P , 0.0001). The treadmill test yielded thehighest peak and predicted oxygen consumption followed bythe bicycle and the upper extremity ergometer test, respec-tively. Conclude that the treadmill test is the best test for mea-suring aerobic fitness levels in patients with chronic low backpain. It yielded the highest peak oxygen consumption com-pared with the other tests, coming closest to measuring maxi-mal oxygen consumption.

Comment by Karen Crawford, RPT.Aerobic conditioning has been a component of several

treatment approaches in the reduction of back pain disability.The specific contribution of aerobic fitness achieved throughthese approaches is not always known. Chronic pain patientstend to be inactive. As a result of this inactivity muscles be-come inefficient at using oxygen and this results in a loss ofmuscle endurance and cardiac output.

The purpose of this study was, 1) to determine which test-ing protocol yields the highest peak values of VO2, heart rates,and respiratory changes ratio in a sample of patients withCLBP; 2) to determine whether the VO2 measures between thetests are significantly different from each other; 3) to deter-mine which factors limit performance in each of these tests;and 4) to compare values of peak VO2 and predicted VO2 maxwith aerobic fitness values published for normal subjects.Chronic low back pain was defined as pain persisting for 3months or more. Patients were excluded from this study if theywere taking medications that influenced heart rate or bloodpressure or if they had coexisting major medical disease, am-putations of one or more extremities, or acute upper or lowerextremity muscular skeletal pain that would interfere with ex-ercise testing or acute psychiatric illness. Thirty participantswith chronic low back pain performed 3 symptom limitedmaximal exercise tests: a treadmill, upper extremity ergome-ter, and a bicycle ergometer. These tests were randomly ad-ministered and heart rate was continuously monitored alongwith oxygen consumption.

Of the 3 tests, the treadmill test is the most functional be-cause of its uses in walking, a function of everyday life. Thisadvantage to bicycle testing is that most Americans are unac-customed to bicycle riding. Many of the patients reported in-creased burning in the thigh and buttocks for sitting on a hardsaddle. Most clinics have access to a treadmill making this apractical test. The treadmill test is, thus, the best measure ofcardiovascular performance; deconditioning of these patientsexpressed itself as early fatigue of peripheral muscles due to in-actively, and limiting their performance on the bicycle andUBE test.


Martha E. Cox, Steeve Asselin, Serge A. Gracovetsky et al:Relationship between functional evaluation measures and self-assessment in nonacute low back pain. (Concordia University,Montréal, Québec, Canada) Spine 2000;25:1817–1826.

In this study, two hypotheses were examined: range of motionand velocity are controllable and inherently correlated withself-assessment; complex spinal coordination patterns such asrange of lordosis cannot be controlled and are independent ofself-assessment. Self-assessment questionnaires were adminis-tered, and indexes of spinal motion and coordination weremeasured through skin marker kinematics. The correlation be-tween self-assessments and biomechanical measures was deter-mined. Self-assessments of function were significantly corre-lated with parameters prone to regulation: range of motion,velocity, and load lifted. In contrast, little correlation wasfound with measures of complex spinal coordination less sus-ceptible to conscious or affective regulation, namely, range oflordosis, and estimated segmental mobility. This effect wasmagnified with increased load. Self-assessment scores were sig-nificantly poorer among insurance referrals, regardless offunctional status. Conclude that simple parameters of thefunctional examination, such as range of motion and velocity,are strongly correlated with cognitive state, and thus the infor-mation they supply is less than ideal. Complex spinal coordi-


nation is a better indicator of the degree of spinal dysfunctionand enhances the process of differentiating between pain, dis-ability, and functional impairment.

Comment by Phillip S. Sizer Jr., MEd, PT.Numerous approaches to the evaluation of lumbar spine

disorders have been proposed. Self-reported disability scalesare frequently implemented, but outcomes can be influencedby patient psychological factors. ROM tests have been fre-quently used for disability rating, but difficulty is encounteredin detecting submaximal patient effort. These investigatorsevaluated the relationships between the Quebec Back Pain Dis-ability Questionnaire and other self-assessment measures, sim-ple functional measures, and coordination patterns using theSpinoscope. From these measures the investigators attemptedto elucidate a more accurate objective measure of biomechani-cal impairment independent from affective or self-assessmentinfluences. The outcomes illustrated that, while simple ROMand velocity measures were strongly correlated with subjectiveindex scores, complex spinal coordination measures were notcorrelated with the same self-assessment outcomes. Addition-ally, the authors suggested that simple ROM does not ensurebiomechanical normalcy in movement. Furthermore, they sug-gested that complex coordination measures that include Rangeof Lordosis (ROL) and Estimate of Inter-segmental Mobility(EISM) may serve as a better compliment to the clinical exami-nation findings associated with lumbar conditions. Finally,they suggested that loading the spine during coordination test-ing further distances the outcomes from the subjective influenceof pain and other factors. These measures may be superior totraditional measures for accurate diagnosis and return-to-workdecisions with patients suffering from seemingly vague condi-tions, such as nonspecific low back pain.


Simo Taimela, Carlo Diederich, Marc Hubsch, Michel Hein-ricy: The role of physical exercise and inactivity in pain recur-rence and absenteeism from work after active outpatient reha-bilitation for recurrent or chronic low back pain: A follow-upstudy. (DBC International, Vantaa, Finland) Spine 2000;25:1809–1816.

This study analyzed the role of physical exercise and inactivityon long-term outcome after active outpatient low back reha-bilitation. One hundred twenty-five patients with low backpain, who had participated in a 12-week active low back reha-bilitation program, were asked about subjective pain and dis-ability on the average of 14 months after the treatment. Theoutcomes were defined as a recurrence of persistent pain andwork absenteeism, and a survival or failure analysis was per-formed between those who had continued exercising and whohad been physically inactive. Recurrences of persistent painduring the follow-up period were fewer (P 5 0.03) amongthose who had maintained regular exercise habits after thetreatment than among those who had been physically inactive.Similarly, work absenteeism was less (P , 0.01) among physi-cally active than among physically inactive persons. However,

patients with good outcome in pain reduction after low backpain rehabilitation were more likely to participate in physicalexercise. Conclude that exercises are beneficial after guidedtreatment in the maintenance of the results of active treatmentfor recurrent chronic low back pain in the long term, but thosewith less favorable outcome in rehabilitation are less likely toparticipate in exercises afterward. In active treatment pro-grams, it is recommended that exercises be incorporated afterthe guided treatment.

Comment by Phillip S. Sizer Jr., MEd, PT.Historically, clinicians have instructed their patients to use

trunk exercise to reduce the severity and duration of the symp-toms and functional losses associated with low back pain(LBP). Through the years increasing evidence has supportedthis notion. However, fewer investigators have evaluated theimpact of exercise after the rehabilitation process has beencompleted. This investigation performed this evaluation andfound that regular, postrehabilitation exercise improved long-term outcomes for patients who had previously suffered fromLBP. Specifically, the investigators reported that ongoing exer-cise performed after an active outpatient rehabilitation pro-gram reduced recurrence of symptoms and absenteeism fromwork, especially after 1 year postonset. Additionally, thesebenefits did not appear to differ for those involved in self-guided exercises versus those participating in a guided pro-gram with back-specific devices in an outpatient treatmentunit. This very interesting article reveals several pearls for thepractitioner. First, subjects were not recruited on a voluntarybasis, so to avoid attracting a group with good self-motivationto alleviate their prevailing symptoms. This measure allowsthe outcomes to be applicable to a varied clinical population.Secondly, although the results favored the use of a guided pro-gram with back specific devices over self-guided exercise, therewere no statistical differences between the 2 approaches. Thus,patients can benefit from self-monitored exercise even whenthey do not have access to a guided program using specific de-vices. Finally, the investigators revealed that poor clinical re-habilitation outcomes predicted postrehabilitation inactivityand reduced success with posttreatment exercise. Thus, the ef-fectiveness of the rehabilitation process may influence pa-tient’s activity level and success of exercise after rehabilitation.


Toni S. Roddey, Sharon L. Olsen, Karon F. Cook, Gary M.Gartsman, William Hanten: Comparison of the University ofCalifornia (Los Angeles) shoulder scale and the simple shuldertest with shoulder pain and disability index: Single-administra-tion reliability and validity. (Texas Woman’s University,Houston, TX) Phys Ther. 2000;80:759–768.

This study compared 2 shoulder measures—the University ofCalifornia-Los Angeles (UCLA) Shoulder Scale and the SimpleShoulder Test (SST)—with the Shoulder Pain and DisabilityIndex (SPADI). One hundred ninety-two patients with shoul-der disorders were recruited from one physician’s office tocomplete the self-report sections of the 3 scales. Cronbach al-


pha values and standard errors of measurements (SEM) werecalculated for each of the multi-item subscales. Validity wasexamined through calculation of correlation coefficientsamong the 3 scales. Factor analysis was completed to assessthe underlying constructs of the SPADI and SST. Cronbachalpha values ranged from 0.85 to 0.95. The SEM values for themulti-item scales ranged from 4.75 to 11.65. Evidence for va-lidity to reflect function was indicated by the correlation be-tween the SST and the SPADI disability subscale. The factoranalysis of the SPADI revealed loading on 1 factor, whereasthe SST loaded on 2 factors. Conclude that all scales demon-strated good internal consistency, suggesting that all items foreach scale measure the same constract. However, SEMS for allscales were high. Factor loading was consistent, suggestingthat patients may not distinguish between pain and function.

Comment by Philip S. Sizer Jr., MED, PT.Clinical practitioners are leaning toward evaluating func-

tional status versus a pure-impairment-based approach to ap-praising shoulder limitations. Several scales have been devel-oped for the evaluation of shoulder function, including the

University of California Los Angeles Shoulder Scale (UCLA),the Simple Shoulder Test (SST), and the Shoulder Pain andDisability Index (SPADI). Investigations demonstrating thepsychometric properties of these scales are limited in number.These investigators attempted to assess those properties, in-cluding internal consistency, reliability, and validity for all 3scales. The analyses demonstrated internal consistency andconstruct homogeneity for the SPADI. However, all 3 scalesdemonstrated rather large standard errors of measure, whichquestions the reliability of the scales for measurement of an in-dividual’s progress. Regarding construct validity, the SPADIdoes not appear to distinguish between pain and dysfunction,disqualifying its use as a gold standard for comparison withother scales. While the SST purports to measure a single con-struct, the data suggests that it appears to measure 2 differentconstructs namely function and comfort. Additionally, theanalyses appear to demonstrate that, while the scales may at-tempt to measure the same constructs, they apparently do not.Finally, the authors suggest that the precision of the UCLAscale is inferior to the other 2 scales and insufficient for follow-ing the progress of individual patients in the clinical setting.

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