Effects of Autogenic Relaxation Training on Electromyographic Activity in Active Myofascial Trigger...

Effects of Autogenic Relaxation Trainingon Electromyographic Activity in Active

Myofascial Trigger Points

Sonja L. BanksDavid W. JacobsRichard Gevirtz

David R. Hubbard

AIISTRACT. Ob.jectives: Prcvious studics in our laboratory huvc su-rt-

gcstcrl thilt myofascial triggcr grints IMTrPsl arc ctcctrically uctivc aritlarc scnsitivc to psychological strcssors even whcn surrounding ntusclctissuc is silcnt. This study invcstigatcd the ett'ccts of Autogcnic Rcl:tx-ation Training IATl on thc ncedleclcctromygraphic IEMGI rcsponsc ufactive MTrPs and adiacent [non-TrP] muscle tibcrs in thc uppcr trapc-zius of 2l chronic pain puticnts.

Mcthods: Participants were trained in AT in thc laborakrry and scnthomc tilr daily practicc tw(Flen days prior ttl data collcction. Mclnanrplitudc nccdlc EMG response tiom thc TrP and non-TrP muscletihi'rs wcrc recurdcd. Data points wcrc recttrdcd in onc minutc pcriodsthroughout tilur conditittns: haselinc, relaxation, ptxt-rclaxittittn. ltnd itnrcntal rrrathcmittical strcssttr.

Sorr.ia L. [Gerstenkornl Banks. PhD. David W. Jacobs. PhD. Richard Gevirtz.PhD. untl David R. Huhhard, MD. are affiliated with the Department of Psycholo-qy.

Calitornia School of Prol'essional Psychology-San Diego.Atldress correspondence to: Sonja L. Banks, PhD, Myolink. LLC. 8llltO Rio San

Diego Drive. Suite 1000, San Diego, CA 92108.This article is hased on a dissertation conducted by Sonja L. Banks. PhD. in

partial fulfillment tbr the requirements of a doctoral degree in Clinical Psychology at

Ca I i tir rn i a School of Professional Psychology'San Diego.This research was presented in March 1996, as a citation paperat the Association

for Applied Psychophysiology and Biofeedback 27th Annual Meeting in Albuquer-que. Nerv Mexico.

Submitted: April 29, 1998.

Revision accepted: June 1, 1998.

Journal of Musculoskeletal Pain, Vol. 6(4) 1998@ 1998 by The Haworth Press, Inc. All rights reserved. 2i

24 JOURNAL OF MUSCULOSKELETAL PAIN

Results: Results tiom paired ,-tests revealed that AI signiticantlyand dramatically reduced ihe needle EMG activity in TrPs fiom base-

Iine to relaxation.Conclusion: The results indicate that relaxation training may be an

eft'ective tool in the treatment of TrP pain possibly mediated by intratu-sal muscle tjbers via the sympathetic nervous system. [Article copies

available lor a fee from The Hsworth Doctunent Delivery Sen'ice: 1dr00-342'

9678. E-nuil address : getinfu@'luworthpressitrc.coml

KEYWORDS. Chronic muscle pain, trigger points, autogcnic training,sympathetic activation of muscle, needle electromyography

INTRODUCTION

Pain of r:ruscular origin is tho most common and debilitating type ofchronic pain (l). Patients with this condition make over 70 million visits lophysicians and 425 nrillion visits to chiropractors (2-a). The only physicalfinding in thc attcctcd muscles of these patients are myotascial trigger points

IMTrPsl which Travcll and Simons have charactcrized as localizcd arcas ofcxquisitc tendcrness associated with a palpable tirmness, a charactcristicrefcrral pattcrn of pain, and a "twitch response"(5).

In an attempt to investigatc autonomic mediat<lrs of muscle pain, t:urgroup has uscd nccdle clcctromyographic [EMC] techniqucs ttl study the

rclationship hctwccn TrP activity and pain (6), stress (7), and cmotions ([l).Thrce t'indings cmcrgc tiom all of these studies cttnccrning TrP EMG' First'TrP EMG activity is clevatcd ctlmpared ttl adiaccnt non-tcnder tihcrs of thcsumc musclc. Sccond, thc TrP EMG activity is climinated hy alpha blockcrs,hut not by curare [a cholincrgic hlocker of striate musclc]. Finally, thc TrPEMG is rcactivc to stressors such as mental arithmetic but not non-strcsstultasks.

Based on these t'indings, we have hypothesized that the main contributorto musculoskeletal pain is intrafusal muscle tjber contractions that are acti-vated via the sympathetic nervous system ISNS] and not the result of extrat'u-

sal muscle contractions as had been previously assumed (9)'Thc currcnt study was designed to determine whether a rclaxation tcch-

nique that does not involve muscular recruitmcnt, but which has been shownto produce cultivated low arousal and sympathetic tonic reduction, AutogenicTraining [ATl (10,11), could produce lsdrtction in TrP activity [relative tonon-tender adjacent musclel in a sample of muscle pain patients. If the TrPactivity is under sympathetic control, we would expect that the EMG activityrvithin the TrP would be reduced by the AI induction without corespondingchanges in the non-tender adjacent muscle.

Ban/c et al.

METHODS

Participants

Participants wcre recruited as they enrolled in a treatment program con-ductcd at thc Pain Rehabilitation Center at Sharp Memorial Hospital in SanDiego, Calitornia. Thirty-two subiects volunteered and were trained in relax-ation. Thrce were never run due to scheduling ditliculties, three canceledthcir appointments, one could not prevent his adjacent muscle tiom "brac-ing," and no TrPs could bc fbund in the trapezius muscle in tbur of thcsubiccts. Thcrctbrc, thc data t'rom the remaining 21 participants was uscd.Scvcntccn were t'emalc, tbur were male, the age rangcd tiom 24 tu 70 ycarswith a mcln agc of 41.5 and a standard deviation of 10.7 years. All partici-pilnts wcrc diagnoscd as having myotascial pain syndrome. Thcy camc to thcstudy with a varicty of previous trcatments, espccially physical thcrapy. Nonchad hccn trcated with hiot'eedback or relaxation thcrapies.

Critcrion ttlr inclusion wcre as tbllows: active TrPs, according to thcdct'initions of Travcll and Simons (5) locatcd in thc uppcr trapczius musclcmcusurahlc hy nccdlc EMG, pain not of neuropathic origin, ugc 20 to 70ycars, n()t prcgnilnt or nursing, not hypcrtcnsivc ur hypotcnsivc, not rccovcr-ing tiom a rcccntly cxpcricnccd major cmotionul trauma. Participants wcrcgivcn a complimcntary rclaxation tapc as compcnsation. This study wasconductcd nccording to thc cthical guidclincs and standards of thc AmcricanPsychologictl Asstrciation, Sharp Hospital, and thc Calitirrnia School ofProtcssional Psychology.

Measures

Elactxtmwtgruphy. Two sterile, monttgxllar nccdlc EMG clcctrodcs wcrcuscd to obtain continuous data on a fbur channel I-410 modcl crlrnputcrmanutircturcd by J & J Enterprises. Data were recordcd using tiltcr scttings of30 ro 10,(X)0 Hz with a notch tilter at 6O Hz [52H2-68Hzl. Sampling ratcswcre 102-1 sample/second.

Skin Conductonce Level and Skin Temperatrrre. Skin conductancc wasmcasurcd using silver/silver chloride electrodes placed on the palmar surtaceof the tirst and second tingers of the hand ipsilateral to the needle electrodes.Room temperature was monitored. A thermistor was taped to the pad of thering tinger of the same hand.

Procedure

At the initial visit, signed consent tbrms were obtained. structured inter-viervs were conducted, and evaluations were completed by an occupational

)<


therapist and a board certitied neurologist. Trigger points were located upon

palpation by the neurologist and the skln over ttre Trp was marked with india

ink.The AI trainer then met with the Patient and explained the basic principles

of the intervention. Aller a practice session, each particiPant was sent home

wirh a fre-recorded AI tape, 15 minutes- in length. The tape. included the

usual Ai phrases abbreviatid for the time frame. It concentrated on heaviness

and warmth in the arms and legs and selt'-statements suggesting whole body

relaxation, calm, quiet. The AT training tape was played on a portable tape

player into headph'ones and participantJwere instructed to practice the relax-

iitiun trp" once iaily at home and monitor their practice. on a providcd log.

Although this proccrlure did not providc a standardized intcrvention, it was

hopccl itrat tnJ participants wouicl be.able to achicve at least a minimal

reriuction in sympathctic arqusal. Participants were also asked to retiuin tiom

taking ,ny pain medication 24 hours prior to the next appointment.

tti,, t,i l4 days latcr, participants returned fbr data ctlllection. Practicc logs

wcrc rcvicwcd io assuri acquisition of the rclaxation resptlnse. Participants

wcrc hclpccl into a gown and placed in an upright chair- A- temperature

thcrnristtx was tapcri-to the tleshy Pad of the ring tinger ipsilatcral to thc

dcsignttecl shouldlr with puin. Subsequently, silver-silverchloride skin con-

ductlancc clcctrtxlcs Iwith Lonductive gel] werc placed on thc first and sccttnd

t'ingcr of thc samc hand and attachcd by velcro. A board certit'icd ncurttlggist,

trai-ncd in TrP idcntitication, then palpited the previgusly markcd arca t.r the

TrP and inscrtcd a nccdle elcctrtxlc into that TrP spot. In addition, anttthcr

nccdlc was inscrtcd to thc same dcpth into a nearby non-TrP location as a

control Ithc proccdurc has heen described in (6'9)]'

Conditions

Busclina: Participunts sat quietly with eyes open tbr two minutes.

Raluxutiut: Particip:rnts sit with eyes closed tbr l0 minutcs whilc thc

prcviously practiced rclaxation tape was glaye{ into headphones.' Ptrst-Iiciaxation: Parricipants sat quietly with eyes opcn tbr two minutcs.

Stressor: The two minuie stressor consisted of instructing the participant

to count backwards hy seven as t'ast as possible starting tiom the numhcr

902. Participants weri hurried by a beeping stopwatch operated by the re-

searcher. This conclition was used as a check to ensure that the needle re-

mained in the same place during the previous conditions. Since we have

shown in prior studiei that the needle TrP EMG levels rise during a mental

arithnretic task, if ntl elevation was seen in this condition, it would have been

possible that the needle slipped out of place.during the relaxation and post-re-

iaxation conditions. Adiacent muscle amplitude levels were usually lowered

with instructions to the participant such as "iust let the arm hang limply," or

Banks et aL

"try to let your shoulder just relax." Participant's arm position was either

resiing comtbrtably in one's lap or hanging comfortably at one's side.

At the conclusion of the session, participants were asked to rate. on a

visual analog scale [VAS, 100 mm linel, the level of stress they t'elt at thc

beginning ot'the session, during successive suhtractions, and at the end of the

expcrimcnt. In addition, participants were askcd to rate the extcnt tlf relax-

ation thcy t'clt tbllowing the rclaxation tape. Anchor points wcre titlm rtortc',

Imcaning no strcss or f'eelings of relaxation I to extcme Irepresenting unhcar-ablc stre.ss tlisabling thcm tiom t'unctioning, or heavy sensatitlns tlf relax-

ationJ.

Data Analysis

C0ntinuously recordcd r(x)t mcan squarc amplitutle EMG data, skin cttn-

ductancc lcvcls ISCLsl, and skin tempcraturc wcre samplcd cvcry l0 scconds

liorn thc onsct of thc proccdurc and avcraged into mcan data points rvhich

wcrc rcp()rtcd in onc minutc pcriods. Condition mcans wcrc hascd on thcsc

scorcs Itwo scorcs in hasclinc, l0 during rclaxatitm, etc.l. Sincc voluntarybracinggrcatty incrcases both the adjaccnt and TrP EMG amplitudcs, all datu

scqucnlcs wcrc chcckcd tbr cvidcncc ttf cxtratusttl cttntractittn [hcrcatlcrrctcrrcd to as hracingl. Dlta points trom adiaccnt musclcs that wcrc 7.(l

micnrvolts or highcr wcrc climinatcd as hcing duc ttl vtlluntary hracing iswcrc thc corrcsponding data points trom thc TrB SCLs. and skin tcmpcraturc.

Thc 7.0 micrtwolt cut-otf is basccl tln prcvious cxpcricncc with scvcr:rl

hundrcd paticnts.Plircd /-tcsts wcrc uscd in all analyscs. Thcsc wcrc trcatctl as planncd

conrparisons. Thus a- t comparis()ns wcre rUn without Corrcctitln tor cxpcr-

inrcntwisc crror and a moditicd Bontbrnrni corrcctittn was uscd whcn rnorc

than thc it-l comparisons wcre used (12).

RESALTS

Tahle I shows the meuns and standard deviations tbr nll ttf thc mcasurcs

across all conditions.

Vatidit-v of the Autogenic Training and Subsequent Stressor

Skin Conductance Levels

In this analvsis, SCLs decreased significantly trom baseline IM = L8.39

micromhos/cm2, SD = 6.151 to the relaxation condition IM = 16.37 micro-

27


TABLE 1. Means and Standard Deviations of Electromyography, skin con-ductance, and Finger Temperature Measures Across Correlations

Basel Relax2 Post Relax3 Stressora

Trigger PointnEMGs inmicrovolts

AdjacentMusclenEMG inmicrovolts

SkinConductancein micromhos/cm2

FingerTemperaturein Degrees Celsius

13.43[3.8616

3.74[1.60]

18.39

[6.151

29.60[3.eI

7.63[2.s31

3.69[1.581

16.37[6.83]

8.65[4.431

3.66I1.sol

16.05

v.741

30.24

[4.31

12.90

[6.441

4.4'.1

n.301

18.89

v.281

29.70

14.21

30.27[4.6]

ltwo-mrnute baseline. 2.lo-mrnute autogenic & training lape. 3two-minute racovery 4two-minute menlal

arithmelrc. 5needle eleclromyography. 6standard deviations. nEMG = needl€ eledromyography.

mhos/cm:, SP = 6.831, with I I l4l = 2.75, P = .016. Estimatcd magnitudc trfctlccr was u2 = .25. Skin ccnductance levels incrcased signiticantly tiom the

prrst-rclaxation condition IM = 16.05 micromhos/cm2, SD = 7.7!l ttl th-c

,tr.rr,,, condition 1AZ = 18.'tl9 micromhos/cm2, ,SD = 7 .281with r I l5] = 3'136,

P = .0()2. Estimated magnitudc of eff'ect was oj = .39.

Skiu Tentpcrature

Skin temperaturc increased tiom baseline IM =29.60'C, SD = 3.9.1 to th!relaxation condition lM = 30.27"C, SD = 4.61, but the change was not signiti-cant, with t U41 ='t.t3, P = .278. However, skin temperature decreascd

signit'icantly iiorir the post-relaxation conditionlM = 30.21"C, SD = 4.31 tcr

thc stressor condition IM = 29.70" C, SD = 4.27, with t [15] = 2.76, P = .015.

Estimated magnitude of efi'ect was a: = .24.

llsual Analog Scale

The VAS data indicated that participants did t'eel relaxed during the AIprocedure IM = 69.33 mm, SD = 24)whete 0 is not at all relaxed and 100 is

ixtremely ielaxecl. During the stressor the_VAS stress scales showed signiti-cant increases [53.62 mm to 72-62 mm, t [201= 2.80, P = .011.|.

Banl<s et al.

Based on this data. it was iudged that the Af, did produce reduction insympathetic activity and in subiective perception of relaxation. Furthermore.as was true in previous studies, serial sevens seems to have produced sympa-thetic arousal and subiective "stress."

A dj a c u t M us c le N e e d Ie E le c t romyographic Ac tivity

Thc ad.iaccnt necdlc EMG levels in microvolts did not decreasc significant-ly tiom bascline IM = 3.74 microvolts, SD = 1.60] to relaxation IM = 3.31

microvolts, SD = l.4ll, with I [4] = 1.51, P = .153. The non-TrP needle EMGlevcls in microvolts signiticantly increased t'rum plst-relaxation IM = 3.59microvolts, SD = 1.521 to thc stressor condition lM = 4.41 micmvolts, .SD =1.30f with / [.5] = 2.t]2,P =.013. Estimatcd magnitudc of cll'cst was url = .24.

Ttr discovcr whcthcr rcductiuns in TrP EMG werc causcd by voluntaryrcduction in thc trapczius as a whole, non-TrP EMG activitics wcrc analyzcd.Sincc thc rcduction was not significant and of small magnitudc. it can hc

ctrncludcd that adiaccnt musclc activity is not thc sourcc of any TrP EMGrcduction. Thc adjaccnt musclc did increase tiom post-relaxation to strcss hutthal change was not uf sutlicicnt magnitudc to ttbscurc our ability to dctcr-minc uny nccdlc slippagc.

Triggcr Point Needle Electrontyttgraphic Activity

Triggcr Point EMG levcls dccreased signiticantly trom hasclinc IM =13.43 micnrvultsl to thc relaxation condition lM = 7.63 microvoltsl, , [14] =5.17, P < .(X)01. Estimutcd magnitude of ctlbct was cui = .56. In adrlition. TrP

EMG lcvcls incrcascd signiticantly tiom the grst-rclaxution {M = 8.6-5 mi-crtrvrrltsf condition to the strcssor condition IM = 12.90 microvoltsl, / [15] =3.(X), P = .009. Estimutcd magnitude of et'fbct was o)j= .27. Thus, indcpcn-

dcnt of non-TrP musclc EMG activity, Af reduccd sympathetic activity and

TrP EMC lctivity whilc the presence of a stressor increased thcm.

Triggcr Point versus Non-Trigger Point Electromyographic Activity

Triggcr point EMG levels were signiticantly hlSher than the non-TrP

needle EMG levels in microvolts when comparing TrP baseline IM = 13.43

microvolts, SD = 3.861 to adjacent muscle baseline IM = 3.74,.SD-= 1.601,

with r [14] = !0.79, P < .0001. Estimated ma-gnitude o-f eff_e_ct was oj = .85.

Trigger point relaxation condition IM = 7.63 microvolts, sD = 2.931was also

signiiicantly higher than the adjacent muscle relaxation condition IM = 3.69microvglts.lp = 1.581, with t [19] = 6.93, P < .0001. Estimated magnitude ofetlbct was a2 = .64.

29


Trigger point post-relaxation condition lM = 8.65 microvolts, SD = 4.431was again signiticantly higher than the adjacent muscle post-relaxation con-dition [M = 3.66 microvolts, SD =-1.50], with , [16] = 4.74, P < .0001.

Estimated magnitude of ell'ect was or = .49.Finally, TrP stressor condition IM = 12.9O microvolts, SD = 6.44] was

signiticantly higher than the adjacent muscle stressor condition IM = 4.4Lmicrovolts, SD = 1.30] with I [15] = 5.07, P < .0001. Estimated magnitude ofeft'cct was ul3 = .54.

Paarson Correlatilns

Skin tempcrature during the relaxation condition was negatively corclatcdwith thc EMG activity in the TrP during the relaxation condition, r [l9l =-.55, P = .012. Othcr corrclations of interest throughout thc conditions: l.adiaccnt musclc EMG activity and SCLs wcre signiticantly and ptxitivclycorrclatcd, r 167l = .53, P < .001, 2. no signiticant correlations wcrc toundhctwccn TrP EMG activity and SCLs, r167l =.11, P =.362,3. TrP EMGactivity was not signiticuntly corrclated with skin temperature, r 167l= - .22,P = .0'16,4. no signilicant corclations were tbund hetwecn skin tcmpcraturcund SCLs, r [tl3] = .09, P = .435, 5. no signiticant corrclations wcrc tirundhclwucn adiaccnt musclc EMG activity and skin iemPerature, r 167l - -.13,P = .297, and tinally,6. no signiticant correlation between the numher ofrclaxation sessions practiccd by the participant and thc level of TrP EMGactivity rcduction in thc rclaxation condition, r 121,] = .07, P = .766.

DISCUSSION

The rcsults indicatc that AT, a technique designed to lower thc activity ofthe SNS, signiticantly lowered the EMG activity rsad tiom active MTrPs.These tindings support the theory that TrP activity is activated and main-taincd in part hy the SNS.

We (9) have previously established that the TrP activity was not blockedby curare, a cholinergic blocker, but was blocked by phentolamine, a tempo-rary alpha-sympathetic blocker, and that psychological stressors could sclec-tively increase this activity while leaving adjacent extrat'usal and non-tendermuscle unafl'ected. As in the previous studies, we tried to eliminate otherexplanations tbr the AT produced reductions. To do this, we controlled anyvariance due to voluntary muscle contraction, checked tbr needle slippage byadministering a stress condition atler the relaxation condition, and cstab-

lished that at least a minimal cultivated low arousal eft'ect occurred.Overall, the lack of conelation fbund among autonomic measures is further

Banl<s et al.

evidence against the traditional theory that "relaxation" and "stl€ss" q:nstitute

total, generalized physiological states (13). Perhaps a segregated SNS comprised

of "subsystems" causes physiological changes that react separately to relaxationand stressor within a target organ without eft'ecting an individual's autonomic

nervous system physiology as a whole. It also may be the tnse that itliosyncratic

diff'crenccs cause physiological reactiom to occur in differing sequcnccs or timctiamcs, causing lag times t'or other physiological markers to show change. [f so,

this would explain why TrP activity is quicker to react than ls skin tcmpraturc.Furthcr rsscarch is needcd to clarity these issues.

Duc to limitations in thc trcatmcnt protocols, we werc not ahlc to stnndurd-izc thc AT training. Clearly some participants were more allbctcd than othcn.Howcvcr. no rclationships between practice logs, selt'-reprrted relaxation, and

TrP EMGs were tbund. Ba.scd on clinical observations, high ttlnic SCLs, and

cool hands, it is fair to concludc that the Af intcrvcntion was only minimall.vcflcctivc. For cxamplc, SCLs only went down to 16.37 micromhtx/cml ttn thc

avcragc during thc relaxation condition. Yet dcspitc this tact, thc TrP EMGdroppcd prccipitously. Thus it appcars that TrP EMG is trndcr spccitic symPil-thctic control. We havc obscrvcd TrP EMC activity to hc quitc stahlc in thc

abscncc uf spccitic stimuli. Participants in our othcr studics havc bccn ob-scrvcd rvith stahlc high TrP EMGs tbr 30 minutcs or morc whcn just iuskcd to

sit quictly (6). This makcs thc rapid reduction in TrP EMG activity tttund inthis study vcry dramatic. Within a two minutc recording pcritxl lcvcls dntppcdtipnr 19 microvolts to a littlc undcr [1 micnrvolts. In spccitic cascs thc dropwits cvcn morc extrcme. It remains to be seen whcthcr a complctc pntttrcol tlfAT with irn cxpcrienccd traincr or tbr that mattcr othcr relaxation tcchniqucs

woutd havc an oven morc protilund effect. Futurc rescarch is also nccdcd tocxplorc thc responsc of cmtltittnal cXperienccs in musclcs othcr than thc uppcr

trapczius.

CONCLT\SION

The localized needle EMG activity tbund within MTrPs wus signiticantlyand dramatically increased by a psychological stressor, mcntal arithmctic,and decreased by Autogenic Relaxation Training.

REFERENCES

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Mersky (Eds.). Progress in Fibromyalgia and Myofascial Pain. Elsevier Science.

Amsterdam. 1993.

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9. Hubhard, DR Jr: Chronic and recurrent muscle pain: Pathophysiology andTreatmcnt, and Review of Pharmacologic Studies. Journal of Musculoskeletal Puin 4(l/2):t23-t43, 1996.

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