The Spine Journal 13 (2013) e29–e34

Case Report

Rectal perforation after AxiaLIF instrumentation: case report and reviewof the literature

Marcus D. Mazur, MD, Bradley S. Duhon, MD, Meic H. Schmidt, MD, MBA,Andrew T. Dailey, MD*

Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 N. Medical Dr. East, Salt Lake City, UT 84132, USA

Received 11 May 2012; revised 22 March 2013; accepted 14 June 2013

Abstract BACKGROUND CONTEXT: Bowel perfora

FDA device/drug

sion to treat pseudoart

spondylolisthesis Gra

back pain of discogen

history and radiograp

Author disclosure

close. MHS: Consult

Speaking/Teaching A

The disclosure key

TheSpineJournalOnlin

* Corresponding

Utah, 175 N. Medica

(801) 581-6908; fax:

E-mail address: n

1529-9430/$ - see fro

http://dx.doi.org/10.10

tion is an uncommon complication of posterior spi-nal surgery. The AxiaLIF transsacral instrumentation system has been used for the treatment of L5–S1 spondylolisthesis and degenerative disc disease since its introduction in 2005 as a potentiallyless invasive alternative to traditional anterior or posterior interbody fusion.PURPOSE: In this article, we report a case of a rectal perforation as a complication of placement ofthe AxiaLIF instrumentation system that was successfully treated without the removal of the device.STUDY DESIGN: Case report.METHODS: The patient presented with progressive back pain and sepsis 3 weeks after an L5–S1fusion done with the AxiaLIF technique at an outside facility. The patient was managed with an-tibiotic therapy and a diverting ileostomy, without the removal of the AxiaLIF device.RESULTS: Over the next year, she had symptoms indicative of nonunion of the operated level andbreakdown at the adjacent level, which were confirmed with imaging. She underwent revision pos-terior spinal fusion without the removal of the AxiaLIF device. Eighteen months after the AxiaLIFdevice was placed, the patient continued to demonstrate no signs of infection recurrence.CONCLUSIONS: Delayed presentation of rectal perforation with a subsequent anaerobic sepsis isa potential complication of the presacral approach to the L5–S1 disc space. Recognition and treat-ment with fecal diversion and long-term intravenous antibiotics is an alternative to device removaland sacral reconstruction. � 2013 Elsevier Inc. All rights reserved.

Keywords: AxiaLIF; Rectal perforation; Transsacral; TranS1; Spinal fusion surgery

Introduction

The AxiaLIF (TranS1, Inc., Wilmington, NC, USA) L5–S1 interbody instrumentation and fusion system providesa minimally invasive alternative to traditional anterior orposterior instrumentation for the treatment of L5–S1

status: Approved (AxiaLIF; for patients requiring fu-

hrosis, unsuccessful previous fusion, spinal stenosis,

de 1 or 2, or degenerative disc disease as defined as

ic origin with degeneration of the disc confirmed by

hic studies).

s: MDM: Nothing to disclose. BSD: Nothing to dis-

ing: Aesculap (B). ATD: Consulting: Biomet (B);

rrangements: AO North America (B), Stryker (B).

can be found on the Table of Contents and at www.

e.com.

author. Department of Neurosurgery, University of

l Dr. East, Salt Lake City, UT 84132, USA. Tel.:

(801) 581-4385.

europub@hsc.utah.edu (A.T. Dailey)

nt matter � 2013 Elsevier Inc. All rights reserved.

16/j.spinee.2013.06.053

degenerative disc disease, multiple recurrent disc hernia-tions, degenerative lumbar scoliosis, spondylolisthesis(Grade I or II), pseudoarthrosis, and symptomatic instabil-ity [1]. In this technique, a presacral retroperitoneal ap-proach is used for axial interbody fusion at L5–S1.Minimally invasive approaches to the lumbar spine with in-strumentation such as the AxiaLIF have been reported toresult in less pain, muscular damage, blood loss, hospitaltime, and narcotic usage than traditional open surgery [2].Published experience with the AxiaLIF system is limited,and most series report few complications, including twowound infections (treated with antibiotics alone) of 71 pa-tients [3,4]. More recently, Botolin et al. [5] reported thecase of a high rectal injury during placement of an AxiaLIFdevice to treat an L5–S1 pseudoarthrosis. The patient wastreated with a diverting ileostomy and antibiotics withoutdevice removal. Because bowel and rectal injuries havenot been reported with great frequency, the managementof this complication is not well established. We present

e30 M.D. Mazur et al. / The Spine Journal 13 (2013) e29–e34

and review our management of a patient with delayed diag-nosis of rectal perforation after AxiaLIF surgery withoutthe removal of the device.

Case report

History and presentation

A 39-year-old woman with a history of discogenic backpain underwent an L5–S1 interbody fusion with the Axia-LIF technique followed by posterior pedicle screw instru-mentation at an outside facility. After an uneventfulhospital course, she was discharged home where she conva-lesced with adequate pain control. During the second weekafter operation, however, she developed progressive backpain that became excruciating and wound tenderness. Thisprompted her to seek treatment at an outside emergencyroom. There she was treated for pain management andgiven oral antibiotics empirically for a presumed wound in-fection. Her severe back pain failed to improve, however,and 3 weeks after her operation, she presented again tothe outside facility with new symptoms of fever, alteredmental status, and wound crepitus and was transferred toour institution for a sepsis evaluation.

On presentation, she was obtunded and meningitic witha temperature of 39�C. She was unable to follow commandsbut would open her eyes to voice. Her peripheral leukocytecount was 19,000/mL, her erythrocyte sedimentation rate(ESR) was 78 mm/h, and her C-reactive protein (CRP) levelwas 24.3 mg/dL. Magnetic resonance imaging of her lum-bar spine showed a posterior lumbar fluid collection withrim enhancement consistent with a lumbar paraspinal ab-scess (Fig. 1).

Surgical intervention and hospital course

Because of the concern for impending septic shock, thepatient was taken urgently to the operating room for surgicald�ebridement and drainage of abscess at the site of the

Fig. 1. Axial T1-weighted magnetic resonance images with contrast enhancemen

erally enhancing fluid collection in the posterior surgical bed.

posterior L5–S1 pedicle screws. Purulent material was en-countered, and cultures taken from the lumbar abscess ulti-mately grew out Bacteroides fragilis. Postoperatively, thepatient was admitted to the intensive care unit for the treat-ment of overwhelming sepsis and received broad-spectrumantibiotics, consisting of vancomycin, ceftriaxone, and met-ronidazole, and aggressive resuscitation with intravenousfluids and vasopressors. Because of a concern that the patienthad a bowel injury, an abdominal computed tomography(CT) was performed, which showed an enhancing mass thatcontained air anterior to the sacrum. Rectal injury was con-firmed with a barium enema (Fig. 2), and a loop ileostomywas performed for fecal diversion.

At this point, AxiaLIF device removal was considered,but the patient began to improve immediately after theileostomy. Although a large sacral defect with the needfor lumbar pelvic reconstruction would be acceptable inthe face of overwhelming sepsis, the rapid improvementimmediately after fecal diversion allowed us to attempta less aggressive option. With the continuation of broad-spectrum antibiotics, the patient became hemodynamicallystable, and her mental status returned to baseline. A sched-uled washout and definitive closure of the posterior lumbarincision was performed on Day 7, and the patient was dis-charged home in stable condition on Hospital Day 10. Be-cause of the patient’s clinical improvement, the decisionwas made to leave the AxiaLIF device in place and monitorthe patient closely for any signs of infection recurrence.

Posthospital course

Intravenous vancomycin, ceftriaxone, and metronidazolewere administered for a total of 10 weeks followed bymaintenance oral metronidazole and levofloxacin for 1year. The ileostomy was reversed after 3 months, and thepatient subsequently had a return of normal bowel function.At a 6-month follow-up examination, the patient had recov-ered from the bowel perforation and sepsis. Her peripheral

t (Left) and without contrast enhancement (Right) demonstrating a periph-

Fig. 2. Barium enema demonstrating contrast extravasation with presacral

pooling (arrow) caused by a posterior rectal perforation.

e31M.D. Mazur et al. / The Spine Journal 13 (2013) e29–e34

leukocyte count was 5,400/mL, her ESR was 6 mm/h, andher CRP level was 0.1 mg/dL.

Over the next year, the patient experienced worseningactivity-dependent low back pain. Imaging demonstrateda nonunion at L5–S1 with lucency around the AxiaLIFdevice, migration of the distal portion of the implant tothe L4–L5 disc space, and widening of the facet joints atL4–L5, all which were consistent with instability (Fig. 3).The patient underwent a revision posterior spinal fusionfrom L4 to S1 with transforaminal interbody fusion at eachlevel. Before the second fusion surgery, her ESR and CRPhad remained within normal limits. Because of the prior in-fection, interbody fusion was performed with bone allograftaugmented by autogenous cancellous bone. Removal of theAxiaLIF device was not attempted because of the large de-fect it would have left in the sacrum.

Fig. 3. Sagittal nonenhanced CT demonstrating implant loosening and nonunion

Axial CT demonstrating widened of the L4–L5 facet joints (Right). Both these

Three years after the bowel perforation, the patient hasrecovered quite well. She now has a solid fusion acrosseach of these levels and has returned to full activity. Up-right radiographs (Fig. 4) show incorporation of the graft,no lucency around the mechanical devices, and no move-ment on flexion and extension radiographs. At 2-yearfollow-up for her revision fusion, she continued to exhibitno signs of infection.

Discussion

Bowel injury during lumbar spine surgery is an uncom-mon but potentially serious complication. The incidence ofbowel injury after lumbar microdiscectomy alone has beenreported at less than 0.1% [6,7]. The risk of injury from ananterior exposure to the lumbar spine is thought to be higher,but nonetheless is still quite low. Faciszewski et al. [8] re-ported no instances of bowel injury from 930 anterior thor-acolumbar and lumbar approaches, whereas Rajaramanet al. [9], Bianchi et al. [10], and Kang et al. [11] each re-ported one bowel injury in their series (544 patients total).When all these experiences are totaled, there were threebowel perforations of 1,474 anterior approaches (0.2%). Re-ports of rectal injuries from AxiaLIF surgery are few. Lind-ley et al. [12] reported two rectal injuries in 68 patientsundergoing AxiaLIF surgery. In one female patient witha history of previous anterior surgical approach to the spine,pelvic inflammatory disease, and diverticulitis, the diagnosisof rectal injury was made on Postoperative Day 4. A generalsurgeon performed a diverting ileostomy that was later re-versed, and a 6-week course of intravenous antibiotics wasadministered [5,12]. At 1 year, this patient demonstrated fu-sion at the AxiaLIF level on CT and radiographs and had re-gained normal bowel function. In another patient, rectalinjury occurred during a L4–L5, L5–S1 AxiaLIF surgery af-ter the interbody graft, and transsacral screws were placed. Atwo-level AxiaLIF requires a more anterior entry point thana one-level procedure, and this may have contributed to rec-tal perforation in this patient. Placement of posterior pedicle

across the L5–S1 interspace 9 months after the AxiaLIF procedure (Left).

images indicate hardware instability. CT, computed tomography.

Fig. 4. Upright radiographs demonstrating intact L4–S1 posterior fusion

hardware without evidence of complication.

e32 M.D. Mazur et al. / The Spine Journal 13 (2013) e29–e34

screws was aborted, and a general surgeon performed surgi-cal repair of the rectal injury and a loop colostomy. Althoughthis patient regained normal bowel function, follow-up im-aging revealed loosening of the transsacral screw. Pediclescrews were placed at a later date, but the patient then devel-oped nonunion at L5–S1 and required posterior fusion andiliac bolt placement. In neither case was removal of the Ax-iaLIF device attempted.

Normally, the midline of the sacrum is relatively freefrom neurovascular and intra-abdominal structures, en-abling a safe entry point for an AxiaLIF [13]. Certain ana-tomical factors, however, may predispose patients toa higher risk of rectal injury. Women have smaller presacralspaces compared with men, which may put women ata higher risk for rectal perforation, vascular injury, or dam-age to the sacral parietal fascia. Some patients may haveabnormal connections of fibrous tissue between the visceraand the abdominal or pelvic wall. Those with rectal adher-ence to the sacrum and patients with adhesions from priorabdominal or anterior spine surgery, infections, pelvic in-flammatory disease, appendicitis, or diverticulitis may haveincreased risk for complications [12,14]. Some authors sug-gest that such patients should receive a preoperative pelvicCT scan with rectal contrast or magnetic resonance imagingof the presacral space to assess the size of the space, checkfor rectal adherence to the sacrum, evaluate for vascularabnormality, and plan instrument trajectory [12]. At a min-imum, a thorough preoperative evaluation should be com-pleted to exclude these risk factors before considering theAxiaLIF approach. Additionally, a full presurgical mechan-ical bowel preparation should be done to decompress therectum and decrease the risk of injury.

Bowel injury may be found intraoperatively or the diag-nosis may be delayed until the signs of abdominal contam-ination manifest in the postoperative period. If discoveredintraoperatively, the injury should be repaired immediately,

and the surrounding area should be copiously irrigated toprevent local abscess formation and peritonitis. If thewound is significantly contaminated, the fusion surgeryshould be abandoned. Delayed diagnosis of a rectal perfo-ration is challenging to manage. The importance of main-taining spinal stability must be balanced with the need toeffectively treat an evolving infection. The decision to keepor remove hardware in this setting should be based onmultiple factors, including concerns for instability and thefeasibility of alternative fixation options. A special consid-eration unique to the AxiaLIF device is its location and thedifficulty of removal. Anatomically, access to the L5–S1 in-terspace can be achieved either through the initial surgicalincision or from a separate anterior approach, but becausethe transsacral screw traverses from the S1 end platethrough the interbody space to the L5 end plate, retrievalwould destabilize both the sacrum and the L5 vertebralbody and leave a large defect in the sacrum. In our patient,long-term stabilization of the lumbosacral spine by an alter-native fixation technique, such as posterior fusion or lum-bopelvic fixation, would have required placing newhardware into the infected surgical site, which might facil-itate dissemination of the infection into uncontaminatedtissues. In addition, the large sacral defect left after the re-moval of the AxiaLIF device might have produced a deadspace that would still harbor bacteria. Therefore, we optedto leave the instrumentation in place and manage the pa-tient with long-term intravenous antibiotics, wound wash-out, and fecal diversion with ileocolostomy. Although sheultimately required a posterior fusion for pseudoarthrosis,this procedure was performed at a time when she had noclinical or laboratory signs of persistent infection.

Fecal diversion was popularized during World War IIand is the cornerstone for the management of rectal injury[15]. Theoretically, a diverting colostomy decreases the riskof an abscess or necrotizing soft tissue infection of the para-rectal fat by reducing contamination with the fecal stream.Fecal diversion without primary repair of a rectal perfora-tion has been advocated to avoid risking exposure of uncon-taminated tissue planes and in cases when the injury cannotbe adequately visualized [15–17]. Rectal perforation froman AxiaLIF is extraperitoneal, and injuries to the extraper-itoneal rectum are distinct and mandate aggressive manage-ment [15]. The extraperitoneal rectum is covered by themesorectum and surrounded by the soft tissues of the pel-vis. Rectal perforation at this level causes contaminationof a closed space occupied primarily by adipose tissue. Thiscan result in the formation of a localized abscess and nec-rotizing soft tissue infection. Moreover, the site of injury atthis level is difficult to identify without full intraperitonealmobilization of the rectum. This is generally not recom-mended because primary repair of an extraperitoneal rec-tum injury does not seem to affect outcomes [17].Presacral abscess drainage may be performed in additionto fecal diversion, although arguments for its necessity re-main controversial [15,16].

e33M.D. Mazur et al. / The Spine Journal 13 (2013) e29–e34

The use of spinal instrumentation increases the risk forpostoperative soft tissue infections [18–20]. Some arguethat the presence of foreign material such as a metal im-plant enables the formation of bacteria-harboring biofilmthat precludes successful eradication of a spinal infection[18,21–23]. Others, however, have shown that deep spinalinfections can be successfully treated without removinghardware [19,24]. Various effective management tech-niques have been described, including empiric broad-spectrum antimicrobial agents followed by microbialculture and sensitivity-directed parenteral antibiotics,long-term suppressive antibiotic therapy in high-risk cases,selective surgical d�ebridement and drainage, and the use ofadjuncts such as continuous irrigation systems and woundvacuums [19,24–26].

Anaerobic bacteria are uncommon pathogens in verte-bral osteomyelitis, discitis, or paraspinal infections. Fewerthan 3% of spine infections are related to anaerobic infec-tions [27–29], most of which are caused by Actinomycesisraelli. Bacteroides species are anaerobic, non–spore-forming gram negative bacilli and are present as normal co-lonic and vaginal flora; however, they account for less thanone-third of anaerobic cases of osteomyelitis [30,31], A re-cent review of 15 cases of Bacteroides osteomyelitis sug-gested two mechanisms of inoculation: direct extensionfrom an intra-abdominal or pelvic infection and bacteremiafrom a recent gastrointestinal procedure [32]. Either mech-anism could have been involved in our patient. In the liter-ature, most patients improved without surgical d�ebridementand were treated with antibiotics alone after the causativeorganism was identified [28,33], Our patient, however,had overwhelming sepsis, no clear organism initially iden-tified, and a large posterior lumbar fluid collection, makingsurgical d�ebridement essential. In most cases, B. fragilis issusceptible to metronidazole, and long-term suppressivetreatment is recommended in high-risk cases [24,32].We elected to treat our patient for 12 months and monitortherapy response through clinical assessment of neurologicfunction and evaluation of wound sites; laboratory eva-luation with serial white blood cell count, ESR, and CRPmeasurements; and radiologic imaging to assess spinalfusion.

Conclusion

Delayed diagnosis of rectal perforation is an uncommonbut potentially devastating complication of the AxiaLIFprocedure. Proper management includes fecal diversion,surgical d�ebridement and/or drainage of the infected tissue,and long-term suppressive antibiotic therapy. With concur-rent antibiotic treatment, the L5–S1 interbody device mayremain in place in some cases, thereby avoiding hardwareremoval and spine destabilization, but close monitoring isessential to ensure appropriate response to intravenous an-tibiotics. If antibiotic therapy fails, device removal may benecessary.

Acknowledgments

The authors thank Kristin Kraus, MSc, for editorial as-sistance in preparing this manuscript.

References

[1] Cragg A, Carl A, Casteneda F, et al. New percutaneous access

method for minimally invasive anterior lumbosacral surgery. J Spinal

Disord Tech 2004;17:21–8.

[2] Marotta N, Cosar M, Pimenta L, Khoo LT. A novel minimally inva-

sive presacral approach and instrumentation technique for anterior

L5-S1 intervertebral discectomy and fusion: technical description

and case presentations. Neurosurg Focus 2006;20:E9.

[3] Aryan H, Newman C, Gold J, et al. Percutaneous axial lumbar

interbody fusion (AxiaLIF) of the L5-S1 segment: initial clinical

and radiographic experience. Minim Invasive Neurosurg 2008;51:

225–30.

[4] Stippler M, Turka M, Gerszten P. Outcomes after percutaneous

TranS1 AxiaLIF� L5-S1 interbody fusion for intractable lower back

pain. Internet J Neurosurg 2008;5. http://dx.doi.org/10.5580/222.

[5] Botolin S, Agudelo J, Dwyer A, et al. High rectal injury during trans-

1 axial lumbar interbody fusion L5-S1 fixation: a case report. Spine

2010;35:E144–8.

[6] Oppel F, Schramm J, Schirmer M, Zeitner M. Results and compli-

cated course after surgery for lumbar disc herniation. Adv Neurosurg

1977;4:36–51.

[7] Ramirez LF, Thisted R. Complications and demographic characteris-

tics of patients undergoing lumbar discectomy in community hospi-

tals. Neurosurgery 1989;25:226–30; discussion 230–1.

[8] Faciszewski T, Winter RB, Lonstein JE, et al. The surgical and med-

ical perioperative complications of anterior spinal fusion surgery in

the thoracic and lumbar spine in adults. A review of 1223 procedures.

Spine 1995;20:1592–9.

[9] Rajaraman V, Vingan R, Roth P, et al. Visceral and vascular compli-

cations resulting from anterior lumbar interbody fusion. J Neurosurg

1999;91:60–4.

[10] Bianchi C, Ballard JL, Abou-Zamzam AM, et al. Anterior retroperi-

toneal lumbosacral spine exposure: operative technique and results.

Ann Vasc Surg 2003;17:137–42.

[11] Kang BU, Choi WC, Lee SH, et al. An analysis of general surgery-

related complications in a series of 412 minilaparotomic anterior

lumbosacral procedures. J Neurosurg Spine 2009;10:60–5.

[12] Lindley EM, McCullough MA, Burger EL, et al. Complications of

axial lumbar interbody fusion. J Neurosurg Spine 2011;15:273–9.

[13] Yuan PS. Authercutaneous presacral space for a novel fusion tech-

nique. J Spinal Disord Tech 2006;19:237–41.

[14] Frantzides CT, Zeni TM, Phillips FM, et al. L5-S1 laparoscopic an-

terior interbody fusion. JSLS 2006;10:488–92.

[15] Merlino J, Reynolds H. Management of rectal injuries. Semin Colon

Rectal Surg 2004;15:95–104.

[16] Cleary RK, Pomerantz RA, Lampman RM. Colon and rectal injuries.

Dis Colon Rectum 2006;49:1203–22.

[17] Tuggle D, Huber PJ Jr. Management of rectal trauma. Am J Surg

1984;148:806–8.

[18] Abbey DM, Turner DM, Warson JS, et al. Treatment of postoperative

wound infections following spinal fusion with instrumentation. J Spi-

nal Disord 1995;8:278–83.

[19] Levi AD, Dickman CA, Sonntag VK. Management of postoperative

infections after spinal instrumentation. J Neurosurg 1997;86:975–80.

[20] Lonstein J, Winter R, Moe J, Gaines D. Wound infection with Har-

rington instrumentation and spine fusion for scoliosis. Clin Orthop

Relat Res 1973;96:222–33.

[21] Richards BS. Delayed infections following posterior spinal instru-

mentation for the treatment of idiopathic scoliosis. J Bone Joint Surg

Am 1995;77:524–9.

e34 M.D. Mazur et al. / The Spine Journal 13 (2013) e29–e34

[22] Collins I, Wilson-MacDonald J, Chami G, et al. The diagnosis and

management of infection following instrumented spinal fusion. Eur

Spine J 2008;17:445–50.

[23] Donlan RM. Biofilm formation: a clinically relevant microbiological

process. Clin Infect Dis 2001;33:1387–92.

[24] Ahmed R, Greenlee JD, Traynelis VC. Preservation of spinal in-

strumentation after development of postoperative bacterial infec-

tions in patients undergoing spinal arthrodesis. J Spinal Disord

Tech 2012;25:299–302.

[25] Rohmiller MT, Akbarnia BA, Raiszadeh K, Canale S. Closed suc-

tion irrigation for the treatment of postoperative wound infections

following posterior spinal fusion and instrumentation. Spine

2010;35:642–6.

[26] Mehbod AA, Ogilvie JW, Pinto MR, et al. Postoperative deep

wound infections in adults after spinal fusion: management with

vacuum-assisted wound closure. J Spinal Disord Tech 2005;18:

14–7.

[27] Perronne C, Saba J, Behloul Z, et al. Pyogenic and tuberculous spon-

dylodiskitis (vertebral osteomyelitis) in 80 adult patients. Clin Infect

Dis 1994;19:746–50.

[28] Saeed MU, Mariani P, Martin C, et al. Anaerobic spondylodiscitis:

case series and systematic review. South Med J 2005;98:144–8.

[29] Sapico FL, Montgomerie JZ. Vertebral osteomyelitis. Infect Dis Clin

North Am 1990;4:539–50.

[30] Finegold SM. Therapy for infections due to anaerobic bacteria: an

overview. J Infect Dis 1977;135(Suppl):S25–9.

[31] Nakata MM, Lewis RP. Anaerobic bacteria in bone and joint infec-

tions. Rev Infect Dis 1984;6(1 Suppl):S165–70.

[32] Elgouhari H, Othman M, Gerstein WH. Bacteroides fragilis vertebral

osteomyelitis: case report and a review of the literature. South Med J

2007;100:506–11.

[33] Lechiche C, Le Moing V, Marchandin H, et al. Spondylodiscitis due

to Bacteroides fragilis: two cases and review. Scand J Infect Dis

2006;38:229–31.