Vertebral osteomyelitis: an analysis of 38 surgically treated cases

The purpose of the study was to evaluate the characteristics of patients with vertebral osteomyelitis who were treated by anterior debridement and interbody fusion. Thirty-eight patients with vertebral osteomyelitis, who were treated between 1980 and 1993, were analyzed in terms of age at the occurrence of disease, duration of disease, type of onset symptoms, radiological type of vertebral destruction, species of pathogen, and surgical result. Thirty-one out of 38 patients (82%) were more than 40 years of age. The patients with severe vertebral destruction were significantly older than those with mild vertebral destruction. Vertebral destruction in the thoracic spine was significantly more severe than that in the lumbar spine. Staphylococcus aureus was identified in only six patients (32% of organism-determined cases). In the present patients who required anterior debridement and bone grafting for this disease, the prognosis was quite good after anterior interbody fusion in conjunction with antibiotics therapy. Received: 3 February 1997 Revised: 7 April 1997 Accepted: 30 July 1997     

Spinal instrumentation for primary pyogenic infection report of 31 patients

The role of spinal instrumentation in the presence of infection is still controversial. Radical debridements of infected vertebrae and disc material and bone grafting usually leaves the spine unstable without some surgical stabilisation. We reviewed 31 cases of primary pyogenic spinal infection treated by radical debridement, bone grafting and posterior (30) or anterior (1) spinal instrumentation. The indication for surgery was the failure of conservative treatment (8), progressive neurological deficit (19) or the lack of diagnosis (3). The clinical, laboratory and radiological parameters were assessed pre and postoperatively. The mean period of follow-up was 3.8 years (1-12 years). The neurological deficit was progressive in 19 patients, following surgery all these patients were improved. The neurological deficit was established in one patient; following surgery, his neurological deficit did not improve. The infection was eradicated in all our patients. The following complications were encountered: (1) three patients developed deep wound infection, which responded to repeated debridement; (2) one death resulted from nosocomial septicaemia, (3) reoperation was carried out on one patient for implant failure and on another for a dislodged anterior bone graft. We conclude that spinal instrumentation may be indicated when after radical debridement of infected vertebrae and disc material and bone grafting the stability of the spine is still compromised. According to the location of the infection and the availability of suitable implants, anterior or posterior instrumentation may be necessary. With appropriate antimicrobial agents, the outcome has been satisfactory in our patients.     

One-stage anterior debridement,bone grafting and posterior instrumentation vs. single posterior debridement,bone grafting,and instrumentation for the treatment of thoracic and lumbar spinal tuberculosis

Purpose

The aim of this study was to compare single posterior debridement, interbody fusion and instrumentation with one-stage anterior debridement, interbody fusion and posterior instrumentation for treating thoracic and lumbar spinal tuberculosis.

Method

From January 2006 to January 2010, we enrolled 115 spinal tuberculosis patients with obvious surgical indications. Overall, 55 patients had vertebral body destruction, accompanied by a flow injection abscess or a unilateral abscess volume greater than 500 ml. The patients underwent one-staged anterior debridement, bone grafting and posterior instrumentation (group A) or single posterior debridement, bone grafting and instrumentation (group B). Clinical and radiographic results for the two groups were analyzed and compared.

Results

Patients were followed 12–36 months (mean 21.3 months), Fusion occurred at 4–12 months (mean 7.8 months). There were significant differences between groups regarding the post-operative kyphosis angle, angle correction and angle correction rate, especially if pathology is present in thoracolumbar and lumbar regions. Operative complications affected five patients in group A, and one patient in group B. A unilateral psoas abscess was observed in three patients 12 months postoperatively. In one of them, interbody fusion did not occur, and there was fixation loosening and interbody absorption. All of them were cured by an anterior operation.

Conclusion

Anterior debridement and bone grafting with posterior instrumentation may not be the best choice for treating patients with spinal tuberculosis. Single posterior debridement/bone grafting/instrumentation for single-segment of thoracic or lumbar spine tuberculosis produced good clinical results, except in patients who had a psoas abscess.     

Bacteria detected after instrumentation surgery for pyogenic vertebral osteomyelitis in a canine model

Objective

This study was designed to identify the presence, type and origin of bacteria adjacent to the metal implant in the infected region in a canine model of pyogenic vertebral osteomyelitis treated with single-stage anterior autogenous bone grafting and instrumentation.

Methods

Dogs with pyogenic spondylodiscitis underwent one-stage debridement, autogenous bone grafting and titanium plate instrumentation and perioperative antibiotic therapy. The implants and adjacent vertebral bones were removed surgically at various postoperative time points (4, 8, 12 and 24 weeks) for bacteria detection. Bacteria were detected from retrieved spinal implants as well as surrounding bones by culture and/or pyrosequencing methods in 17 (85 %) of all 20 animals. The positive rate for bacteria presence was 45 % by culture and 80 % by pyrosequencing method.

Results

Radiological or macroscopic examination showed no signs for infection recurrence in any animal regardless of bacteria presence at the surgical site. However, organism identical with the causative bacterium for spinal infection was found in only two of nine culture-positive animals.

Conclusion

Within the confines of the study, the use of metallic implants in an infected area did not lead to a clinically relevant infection although bacteria may exist at the surgical site. The use of metallic implants in an infected area of the spine is safe. The metallic implants may not be the “culprit” for the persistence or recurrence of infection.     

Treatment of hematogenous pyogenic vertebral osteomyelitis with anterior debridement and primary bone grafting

From 1971 to 1984 at the University of Rochester Medical Center, 23 adult patients underwent surgical treatment via an anterior approach for pyogenic vertebral osteomyelitis. Data from 21 patients with greater than 2-year follow-up is presented in this report. Surgical debridement via an anterior approach was performed in all 21 patients. Bone grafting with iliac crest or rib strut was done in 19 patients. Clinical follow-up averaged 4 years, with a range of 2 years to 9 years, 9 months. No patient had a recurrence of osteomyelitis. All patients with neurologic deficits recovered without functional motor or sensory deficits. Of the 19 patients grafted, 18 showed roentgenographic evidence of fusion, and one went on to a pseudarthrosis. The average increase in kyphosis at the infection site was 3 degrees. In selected patients with pyogenic vertebral osteomyelitis requiring surgical treatment, anterior debridement and primary bone grafting in conjunction with appropriate antibiotics is successful in treating the infection and promoting osseous fusion in a high percentage of cases.     

Preliminary results of staged anterior debridement and reconstruction using titanium mesh cages in the treatment of thoracolumbar vertebral osteomyelitis.

BACKGROUND CONTEXT: Vertebral osteomyelitis can be successfully treated with spinal immobilization and parenteral antibiotics. Failure of medical therapy may necessitate surgical treatment consisting of anterior debridement and structural anterior column reconstruction. Autologous structural bone graft has traditionally been the gold standard in anterior column reconstruction. Because of the morbidity related to graft harvest, vertebral body replacement cages have emerged as a viable option for reconstructing a deficient anterior column. PURPOSE: To evaluate the efficacy of titanium mesh cages in the reconstruction of anterior column defects in the presence of active pyogenic infection. STUDY DESIGN: Prospective case series. METHODS: Eleven patients underwent operative treatment for osteomyelitis of the thoracolumbar spine using staged anterior debridement and reconstruction with cylindrical titanium mesh cages followed by delayed posterior spinal fusion with pedicle screw instrumentation during a 2-year period. Patients were postoperatively evaluated clinically and radiographically. RESULTS: Follow-up averaged 17+/-9 months. Average increase in kyphosis of 10+/-6 degrees corresponding to 4+/-4 mm loss in the height (subsidence) of the anterior construct. One patient died during revision surgery for hardware failure. Seven of the remaining 10 patients have not required antibiotics after the initial postoperative course of treatment. Three patients are maintained on chronic suppressive therapy as a precaution. There has been no evidence of recurrence or residual infection in any patient. Seven of the 10 patients were pain free at latest follow-up. There has been one case of pseudarthrosis. CONCLUSION: Cylindrical titanium mesh can be used with consistently good results for large anterior column defect reconstructions even in the face of active pyogenic infection. In our cohort of patients with pyogenic vertebral osteomyelitis, the use of titanium mesh cages has not been associated with early recurrence of infection.     

Single-stage treatment of pyogenic spinal infection with titanium mesh cages

STUDY DESIGN: Single institution retrospective review. OBJECTIVES: To report a series of pyogenic spinal infections treated with single-stage debridement and reconstruction with titanium mesh cages. SUMMARY OF BACKGROUND DATA: Various studies have reported surgical results of pyogenic spinal osteomyelitis with anterior debridement, strut grafting and fusion, including delayed posterior spinal instrumentation. Additionally, various authors have recommended against the use of instrumentation because of the concern about glycocalyx formation on the metal and chronic infection. At our institution, we routinely treat chronic vertebral osteomyelitis with single-stage debridement, reconstruction with a titanium mesh cage filled with allograft chips and demineralized bone matrix, and posterior pedicle screw instrumentation. To our knowledge, this is the largest single series reporting single-stage debridement and instrumentation of pyogenic spinal infection with titanium mesh cages and posterior instrumentation. MATERIALS AND METHODS: We retrospectively reviewed the patient records and radiographs of 21 consecutive patients (average age 49.3 years, range 23 to 80 years) with pyogenic vertebral osteomyelitis, all treated with titanium mesh cages. Average follow-up was 44 months (range, 25 to 70 months). Spinal levels included 6 thoracic, 4 thoracolumbar, 9 lumbar, and 2 lumbosacral (L5-S1) lesions. All patients had preoperative serum evaluation, which usually included blood cultures, complete blood count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP), in addition to plain radiographs and magnetic resonance imaging. A positive needle biopsy was available in only 2/7 patients (29%), and overall, preoperative pathogen identification was available in only 7/21 patients (33%). All patients were treated postoperatively with a minimum of 6 weeks of intravenous antibiotics, with a specific antibiotic regimen directed toward the postoperative pathogen when identified (17/21 cases). Extensive radiographic evaluation was also performed. RESULTS: ESR and CRP were routinely elevated (18/20 and 11/17 cases respectively), whereas the white blood count was elevated in only 8 out of 21 cases (38%). The average duration of symptoms to diagnosis was approximately 13.6 weeks (range 3 weeks to 10 months). The indications for surgery included neurologic compromise, significant vertebral body destruction with loss of sagittal alignment, failure of medical treatment, and/or epidural abscess. All patients had resolution of infection, as noted by normalization of the ESR and CRP. Further, 16 out of 21 patients also had a significant reduction of pain. There were no deaths or new postoperative neurologic compromise. The most common pathogen was Staphylococcus aureus. Two patients required a second surgery (posterior irrigation and debridement) during the same admission for persistent wound drainage. Radiographically, the average segmental kyphosis (or loss of lordosis) was 11.5 degrees (range, 0 to 24 degrees) preoperatively, and +0.8 degrees (range, -3 to +5 degrees) at latest postoperative follow-up. There was an average of 2.2 mm cage settling (range, 0 to 5 mm) on latest follow-up. There were no instrumentation failures, signs of chronic infection, or rejection. CONCLUSIONS: Titanium mesh cages present a viable option for single-stage anterior surgical debridement and reconstruction of vertebral osteomyelitis, without evidence of chronic infection or rejection. When used in conjunction with pedicle screw instrumentation, there is minimal cage settling without loss of sagittal alignment.     

Pyogenic Vertebral Osteomyelitis after Acute Bacterial Prostatitis: A Case Report

A case of pyogenic vertebral osteomyelitis after acute bacterial prostatitis in a 78-year-old man is reported. The rarity and subtle clinical presentation of this condition, and the delayed appearance of radiologic signs of progression to destructive osteomyelitis, contributed to a significant delay in diagnosis. An arterial blood culture positive for bacterial growth during the episode of acute prostatitis suggested that bacteremia might result from hematogenous spread of the infection to the vertebral column via the venous system. Since intensive antimicrobial therapy proved ineffective, debridement of the first and second lumbar vertebral bodies, and anterior spinal fusion from the twelfth thoracic to the third lumbar vertebrae were performed. The patient's high fever and severe lumbago subsided immediately after the surgery. The possibility of development to pyogenic vertebral osteomyelitis should be kept in mind when treating a serious genitourinary tract infection.     

Adjuvant Posterior Stabilization in the Management of Tuberculous Spondylitis of the Dorsal and Lumbar Spine

Objective Posterior instrumentation and stabilization allowing early mobilization, shortened hospital stay and maintenance of correction after debridement and bone grafting for tuberculous spondylitis through an anterior approach. Indications Tuberculous spondylitis requiring anterior drainage, debridement and decompression, as well as interbody fusion. Significant bone loss of vertebral body. Kyphosis > 25° Concomitant posterior column disease. Contraindications Poor general health precluding such an extensive intervention. Superinfection of tubercoulous sinus on the back. Surgical Technique The first stage consists of anterior debridement and bone grafting. During the second stage, preferably performed at the same sitting, a posterior stabilization is done. At the level of the thoracic spine and for all patients with osteoporosis irrespective of the level, a sublaminar wiring (Hartshill) is performed. At the lumbar spine pedicular screw fixation and Steffee plating are done in the absence of osteoporosis. Results Between June 1993 and December 1996 25 patients (nine men, 16 women, average age 38.5 years) with tuberculous spondylitis underwent this two-stage procedure. Average length of follow-up 16.9 months. A preoperative neurologic deficit seen in 15 patients persisted only in two. The overall loss of correction amounted to 6.5°. The average time of fusion was 6 months. No implant failures were recorded. A screw pull-out secondary to infection accompanied by loss of correction occurred in one patient. Another patient experienced a transient neurologic deficit.     

Posterior instrumentation, anterior column reconstruction with single posterior approach for treatment of pyogenic osteomyelitis of thoracic and lumbar spine

Purpose

Surgical treatment of thoracolumbar osteomyelitis consists of radical debridement, reconstruction of anterior column either with or without posterior stabilization. The objective of present study is to evaluate a case series of patients with osteomyelitis of thoracic and lumbar spine treated by single, posterior approach with posterior instrumentation and anterior column reconstruction.

Methods

Seventeen patients underwent clinical and radiological evaluation pre and postoperatively with latest follow-up at 19 months (8–56 months) after surgery. Parameters assessed were site of infection, causative organism, angle of deformity, blood loss, duration of surgery, ICU stay, deformity correction, time to solid bony fusion, ambulatory status, neurologic status (ASIA impairment scale), and functional outcome (Kirkaldy-Willis criteria).

Results

Mean operating time was 207 min and average blood loss 1,150 ml. Patients spent 2 (1–4) days in ICU and were able to walk unaided 1.6 (1–2) days after surgery. Infection receded in all 17 patients postoperatively. Solid bony fusion occurred in 15 out of 17 patients (88 %) on average 6.3 months after surgery. Functional outcome was assessed as excellent or good in 82 % of cases. Average deformity correction was 8 (1–18) degrees, with loss of correction of 4 (0–19) degrees at final follow-up.

Conclusions

Single, posterior approach addressing both columns poses safe alternative in treatment of pyogenic vertebral osteomyelitis of thoracic and lumbar spine. It proved to be less invasive resulting in faster postoperative recovery.     

Adjuvante dorsale Stabilisierung der thorakalen und lumbalen Wirbelsäule bei tuberkulöser Spondylitis

Objective Posterior instrumentation and stabilization allowing early mobilization, shortened hospital stay and maintenance of correction after debridement and bone grafting for tuberculous spondylitis through an anterior approach. Indications Tuberculous spondylitis requiring anterior drainage, debridement and decompression, as well as interbody fusion. Significant bone loss of vertebral body. Kyphosis > 25°. Concomitant posterior column disease. Contraindications Poor general health precluding such an extensive intervention. Superinfection of tuberculous sinus on the back. Surgical Technique The first stage consists of anterior debridement and bone grafting. During the second stage, preferably performed at the same sitting, a posterior stabilization is done. At the level of the thoracic spine and for all patients with osteoporosis irrespective of the level, a sublaminar wiring (Hartshill) is performed. At the lumbar spine pedicular screw fixation and Steffee plating are done in the absence of osteoporosis. Results Between June 1993 and December 1996 25 patients (nine men, 16 women, average age 38.5 years) with tuberculous spondylitis underwent this two-stage procedure. Average length of follow-up 16.9 months. A preoperative neurologic deficit seen in 15 patients persisted only in two. The overall loss of correction amounted to 6.5°. The average time to fusion was 6 months. No implant failures were recorded. A screw pull-out secondary to infection accompanied by loss of correction occurred in one patient. Another patient experienced a transient neurologic deficit.     

Single-stage anterior debridement and fusion with autografting and internal fixation for pyogenic lumbar spondylodiscitis

Introduction  

Patients with pyogenic lumbar spondylodiscitis can be successfully treated by non-operative methods. However, the typical operation for this condition includes debridement of the infected site, bone grafting and internal fixation to stabilize the spine. Single-stage anterior debridement and fusion with autografting and internal fixation of one spinal segment were performed on nine patients with pyogenic lumbar spondylodiscitis. This operative procedure is rarely documented for pyogenic lumbar spondylodiscitis.     

Surgical treatment of pyogenic vertebral osteomyelitis with spinal instrumentation

Pyogenic vertebral osteomyelitis responds well to conservative treatment at early stage, but more complicated and advanced conditions, including mechanical spinal instability, epidural abscess formation, neurologic deficits, and refractoriness to antibiotic therapy, usually require surgical intervention. The subject of using metallic implants in the setting of infection remains controversial, although more and more surgeons acknowledge that instrumentation can help the body to combat the infection rather than to interfere with it. The combination of radical debridement and instrumentation has lots of merits such as, restoration and maintenance of the sagittal alignment of the spine, stabilization of the spinal column and reduction of bed rest period. This issue must be viewed in the context of the overall and detailed health conditions of the subjecting patient. We think the culprit for the recurrence of infection is not the implants itself, but is the compromised general health condition of the patients. In this review, we focus on surgical treatment of pyogenic vertebral osteomyelitis with special attention to the role of spinal instrumentation in the presence of pyogenic infection.     

前路病灶清除植骨内固定治疗胸腰椎结核

目的总结前路病灶清除植骨内固定治疗脊柱结核的临床效果。方法对12例脊柱结核患者采用一期病灶清除结合植骨内固定,手术前后配合正规化疗,根据X线片观察脊柱融合时间和脊柱后凸角度变化。结果随访时间8~45个月,全部病例未出现严重并发症。植骨界面骨性融合时间4.5~8个月。后凸矫正度数为7°~18°。结论一期病灶清除植骨内固定治疗脊柱结核,骨结构重建可靠,治疗过程相对简化,效果肯定。     

Two-staged operation for thoracolumbar osteomyelitis following methicillin-resistant staphylococcus aureus infection of a craniectomy wound--case report.

A previously healthy 53-year-old woman developed pyogenic vertebral osteomyelitis (PVO) manifesting as progressive lumbago following wound infection of a decompressive craniectomy performed for brain contusion caused by a traffic accident. Magnetic resonance imaging disclosed vertebral osteomyelitis at T-12 and L-1 with paravertebral abscess. Anterior debridement and fusion using autografts were performed at the first operation. Methicillin-resistant Staphylococcus aureus (MRSA) was cultured from the abscess specimen. Antibiotic therapy resolved the infection. Pedicle screw fixation was performed at the second operation. The patient became free from back pain and no recurrence of infection was seen. The diagnosis of PVO is frequently observed or delayed because of the nonspecific symptomatic presentation in the early stage. Coexistent infection or trauma makes early diagnosis more difficult. Indications and timing of instrumentation for the spinal column infected with MRSA is difficult. Two-staged operation with anterior debridement and posterior instrumentation after eradication of the infection is a safe and effective procedure for MRSA vertebral osteomyelitis.     

病灶清除植骨内固定治疗胸腰椎结核

目的评价采用病灶清除植骨内固定术治疗胸腰椎结核的疗效。方法采用前路或前后路联合病灶清除植骨内固定术治疗16例胸腰椎结核患者,术后抗结核药物治疗9~12个月。结果患者均获得随访,时间6~48个月。9例术前神经功能障碍者术后均获得明显改善:改善至C级1例,D级1例,恢复至E级7例,无神经功能障碍加重者。除1例植骨融合延期外,其余患者植骨均愈合良好。Cobb角术前22.6°~48.5°,术后10°~21°。结论胸腰椎结核采用病灶清除植骨融合及内固定术,彻底清除病变组织,可重建脊柱稳定性,提高脊柱结核的治愈率。     

一期前后联合入路手术治疗胸腰椎脊柱结核

目的探讨胸、腰椎结核的手术治疗方式。方法42例胸、腰椎结核患者，男24例，女18例；年龄为22～73岁，平均38．2岁。其中胸椎结核11例，胸腰段结核14例，L2以下腰椎结核17例。术前采用四至六联正规抗结核治疗至少3周，所有患者均采用后路椎弓根螺钉系统矫形内固定、椎板间植骨（人工骨），同期行前路病灶清除联合自体髂骨植骨术。前路手术切口根据病变节段分别采用经胸腔入路、胸膜外腹膜外入路、经腹膜外肾切口、经腹直肌旁腹膜外切口及腹正中腹膜外入路。平均手术时间为230min，术中平均出血量为550ml。术后继续抗结核治疗，术后4周下地行走。结果所有患者均获得8～46个月随访，平均24．3个月。全部患者植骨融合，腰背痛症状缓解，神经功能明显恢复，复查血沉及CRP均正常。结论对于非手术治疗效果不佳的胸、腰椎结核患者，采用后路矫形内固定、前路病灶清除植骨的一期手术方式可获得满意的疗效。     

Surgical therapy of unspecific and specific Spondylodiscitis

AIM: The aim of this study was to evaluate the clinical and radiological results of surgical treatment of thoracic and lumbar vertebral osteomyelitis by means of one-stage extrafocal posterior stabilisation, anterior debridement, and anterior column reconstruction. METHOD: A retrospective analysis of the peri- and postoperative parameters of 62 patients with a clinical and radiographic follow-up of 2.6 years that were available for 46 patients was performed. In 42 cases, the anterior column was restored with structural bone grafts, in 20 patients, expandable titanium cages filled with morsellised autologous bone and antibiotic collagen sponges were used. To assess the course of spinal alignment a radiometric analysis was undertaken. Furthermore, the Roland-Morris score (RMS) was applied to evaluate the back pain-related disability. RESULTS: The diagnosis was made no earlier than 2.7 months after the first symptoms. Preoperatively, 40 % of the patients presented with neurological impairment, of these 76 % improved after surgery. Staphylococcus aureus was the most common pathogen isolated (32 %), Mycobacterium tuberculosis was found in 11 % of the patients. Except for one patient with revision for persistent infection and consecutive failure of the bone graft, primary eradication of the infection was achieved in all cases. At follow-up, bony fusion was radiographically observed in all patients. When using cages, the segmental loss of correction was significantly lower than when using bone grafts (1.0 vs. 4.1 degrees ). At follow-up the RMS averaged 6.6. CONCLUSION: One-stage extrafocal posterior stabilisation combined with anterior debridement and anterior column reconstruction with bone grafts or titanium cages is a safe and effective strategy for patients with vertebral osteomyelitis in need of surgery. Titanium cages have proven to be biomechanically advantageous, especially in cases of extensive destruction and are not associated with higher rates of persistence or recurrence of infection compared to autologous bone grafts.     

胸腰段结核的手术治疗

目的：探讨胸腰段结核的手术治疗,以提高胸腰段结核的手术治愈率。方法：１９９１年１月至１９９９年１月,我院共实施胸腰段结核手术３４例,其中前路病灶清除兼椎间植骨融合术３２例,后路病灶清除并横突间植骨融合术２例。结果：术后对所有病人进行了０．５￣６．５年,平均３．５年的随访,手术优良率为９４．１％。结论：多数胸腰段结核适合于前路病灶清除术Ⅰ期椎间植骨融合术,部分可以选用后路病灶清除并Ⅰ期横突间植骨融合     

Osteomyelitis of the cervical spine: a potentially dramatic disease

Osteomyelitis of the cervical spine is a rare disease, representing only 3% to 6% of all cases of vertebral osteomyelitis. In contrast with other locations of spinal infections, osteomyelitis of the cervical spine can be a much more dramatic and rapidly deteriorating process, leading to early neurologic deficit. Thus, the disease must be diagnosed quickly and appropriate therapy initiated as soon as possible. The clinical course, therapy, and outcome of 15 patients treated for osteomyelitis of the cervical spine are presented. Nine of 15 patients presented with a neurologic deficit at the time of diagnosis. Surgical treatment consisted of radical debridement of the infected bone and either immediate bone grafting and stabilization as a one-step procedure or interval antibiotic treatment before bone grafting and surgical stabilization as a second procedure. A favorable outcome was achieved by early and aggressive surgical intervention, including complete resolution of neurologic deficits in more than 50% of the patients and complete bony fusion in all but one patient. The authors prefer additional posterior rather than anterior stabilization alone to perform fusion over a shorter distance involving only the infected segments.