Surgical management of pyogenic discitis of lumbar region

Influence of instrumentation type on outcomes after surgical management of spondylodiscitis: a systematic review and meta-analysis

OBJECTIVE

Spondylodiscitis refers to infection of the intervertebral disk and neighboring structures. Outcomes based on instrumentation type are not well reported in the literature, but are important in establishing guidelines for surgical management of spondylodiscitis. This study aims to clarify the effect of instrumentation material selection on clinical and radiographic outcomes in patients with spondylodiscitis.

METHODS

Studies that evaluated the use of polyetheretherketone (PEEK), titanium, allograft, and/or autologous bone grafts for spondylodiscitis were identified in the literature. Radiographic and clinical data were analyzed using a meta-analysis of proportions, with estimated risk and confidence intervals reported for our primary study outcomes.

RESULTS

Thirty-two retrospective studies totaling 1088 patients undergoing surgical management of spondylodiscitis with PEEK, TTN, allograft, and autologous bone graft instrumentation were included. There were no differences in fusion rates (p-interaction = 0.55) with rates of fusion of 93.4% with TTN, 98.6% with allograft, 84.2% with autologous bone graft, and 93.9% with PEEK. There were no differences in screw loosening (p-interaction = 0.52) with rates of 0.33% with TTN, 0% with allograft, 1.3% with autologous bone graft, and 8.2% with PEEK. There were no differences in reoperation (p-interaction = 0.59) with rates of 2.64% with TTN, 0% with allograft, 1.69% with autologous bone graft, and 3.3% with PEEK.

CONCLUSIONS

This meta-analysis demonstrates that the choice of instrumentation type in the surgical management of spondylodiscitis resulted in no significant differences in rate of radiographic fusion, screw loosening, or reoperation. Future comparative studies to optimize guidelines for the management of spondylodiscitis are needed.

Discitis Following Radiofrequency Nucleoplasty: A Case Report

Introduction

Radiofrequency nucleoplasty is a minimally invasive procedure to treat chronic low back pain, especially mild degenerative disc diseases. Discitis after radiofrequency nucleoplasty is a rare case.

Case Presentation

A 62-year-old male patient with a chief complaint of 10 years low back pain, gradually worsening for the last two years, a history of hypertension, chronic kidney disease, and routine dialysis twice a week, referred to the center. He underwent a lumbar medial branch block using radiofrequency and radiofrequency nucleoplasty procedure of lumbar 4-5 (L4-L5). Three weeks after the intervention, he could not move his legs, associated with urinary and fecal incontinence. MRI (magnetic resonance imaging) of the lumbar spine was performed, and the results indicated hyperintensity in L4-L5, suspicious of discitis. Laminectomy at L4 and L5 was performed. Eight months after surgery, the patient could feel and lift legs, and urinary and fecal incontinence was also controlled.

Conclusions

Early diagnosis of discitis is critical and challenging. Delay in diagnosis may lead to treatment delay and the development of neurological deficits. Comprehensive treatment with bed rest, antimicrobial therapy, and sensible application of timely surgery are essentials to an optimal outcome.

Triaging Spine Surgery and Treatment during the COVID-19 Pandemic

OBJECTIVE

To utilize evidence-based medicine to help determine guidelines for spinal surgery during the Covid-19 era.

METHODS

A literature review was performed of peer-reviewed articles focused on indications for common procedures in spine surgery. Based on these indications, we sub-categorized these procedures into elective, urgent and emergent categories. Case examples provided.

RESULTS

Indications for spinal surgery were reviewed based on current literature and categorized. This manuscript presents a decision-making algorithm to help provide a guideline for determining the appropriateness of proceeding with spinal surgery during this COVID-19 time period.

CONCLUSIONS

Spinal surgery during the COVID-19 pandemic is an intricate challenging decision-making process, involving clinical, sociologic and economic factors.

CT-guided discitis-osteomyelitis biopsies with negative microbiology: how many days should we wait before repeating the biopsy?

PURPOSE

To determine the number of days to positive CT-guided biopsy sample culture in patients with discitis-osteomyelitis.

METHODS

Our study was IRB approved and HIPAA compliant. All CT-guided biopsies performed for acute discitis-osteomyelitis with positive microbiology between 2002 and 2018 were reviewed. Microbiological organism and days to positive biopsy were documented. Mean, median, skew, and standard deviation were calculated. The proportion of positive cultures that become positive after each day has elapsed was also calculated.

RESULTS

There were 96 true positive cultures, with 64 (67%) male and 32 (33%) female, ages 57 ± 18 (range 19-87) years. Overall, including all culture results, the mean number of days to positive culture was 2.9 ± 3.5 days. The median number of days was 2, with a positive skew of 2.9. At days 1, 2, 3, 4, and 5, 48%, 68%, 78%, 85%, and 89%, respectively, of biopsy samples had a positive microbiology culture.

CONCLUSION

Approximately three-quarters of discitis-osteomyelitis pathogens will be identified by biopsy sample culture by 3 days after CT-guided biopsy. This finding should be considered if planning for a repeat biopsy in the setting of a negative microbiology culture.

Anterior Cervical Debridement and Fusion for Cervical Pyogenic Spondylodiscitis: Use of Anterior Cervical Plating or Not?

STUDY DESIGN

Retrospective multicenter case series.

OBJECTIVE

We sought to evaluate the safety and efficacy of anterior cervical plating in anterior cervical debridement and fusion (ACDF) for patients with cervical pyogenic spondylodiscitis (CPS).

SUMMARY OF BACKGROUND DATA

Due to concerns about bacterial seeding on the foreign material after instrumentations in pyogenic infections, the safety and efficacy of anterior cervical plating for CPS are still undetermined and controversial. Little information is available about the safety and efficacy of anterior cervical plating to manage CPS.

METHODS

Twenty-three patients who underwent ACDF with (n = 12) or without (n = 11) plating for CPS were included. The mean age was 62.6 years. Medical records were reviewed and radiological parameters including segmental height, segmental angle, C2-C7 angle, and fusion status were analyzed. The mean follow-up period after surgery was 21.3 months.

RESULTS

After ACDF with plating, segmental height, segmental angle, and C2-C7 angle were significantly improved compared with preoperative conditions and remained well-maintained at the last follow-up. After ACDF without plating, three radiological parameters were also initially improved compared with preoperative condition, but significantly deteriorated to preoperative levels at the time of the last follow-up. The fusion rate was higher in the ACDF with plating group compared with the ACDF without plating group (90.9% vs. 63.6%; P < 0.01). One patient who received ACDF with plating and four patients who received ACDF without plating underwent revision surgery due to nonunion or bone graft dislodgement. No recurrence of pyogenic spondylodiscitis occurred in either group.

CONCLUSION

ACDF with plating showed better surgical outcomes compared with ACDF without plating for CPS. We recommend the use of anterior cervical plating, which can provide biomechanical stability, for better healing of CPS. To our knowledge, this is the largest surgical case series of CPS.

LEVEL OF EVIDENCE

4.

Spontaneous spondylodiscitis: review, incidence, management, and clinical outcome in 44 patients

OBJECTIVESpontaneous spondylodiscitis remains uncommon but is a serious complication of the vertebral column. Risk factors include diabetes, hemodialysis, intravenous drug abuse, and chronic steroid use, and pain is the most common presenting symptom. This study aims to review the literature and report on the incidence, management, and clinical outcome of spontaneous spondylodiscitis in 44 patients.METHODSThis is a prospective study including 44 patients with spontaneous spondylodiscitis managed in the neurosurgery department of Cairo University Hospitals during the period between January 2012 and October 2017. All patients had a full clinical assessment, laboratory tests, radiological studies in the form of MRI with and without contrast, and a postoperative follow-up of up to 12 months.RESULTSTwelve cases underwent conservative treatment in the form of complete bed rest, intravenous antibiotics, and a spinal brace. Ten cases underwent surgical intervention in the form of laminectomy, debridement, and open biopsy. Twenty-two cases underwent laminectomy and surgical stabilization with fusion. There were 15 cases of tuberculous spondylodiscitis, 6 cases of brucellosis, 6 cases of pyogenic infection, and 17 cases in which no organism could be detected.CONCLUSIONSOnce the primary diagnosis is confirmed, early and adequately prolonged antibiotic therapy is recommended for spontaneous spondylodiscitis. Some cases can be successfully treated with conservative treatment alone, whereas surgery may be needed in other cases such as severe destruction of endplates, spinal abscess formation, mechanical instability, neurological deficits, and severe pain that have failed to respond to conservative treatment.

Pathogen Identification in Suspected Cases of Pyogenic Spondylodiscitis

Pyogenic spinal infection continues to represent a worldwide problem. In approximately one-third of patients with pyogenic spondylodiscitis, the infectious agent is never identified. Of the cases that lead to organismal identification, bacteria are more commonly isolated from the spine rather than fungi and parasites. This study applied universal prokaryotic 16S rRNA PCR as a rapid diagnostic tool for the detection of bacterial agents in specimens from patients suspected of pyogenic spondylodiscitis. Gram and Ziehl-Neelsen staining were used as a preliminary screening measure for microbiologic evaluation of patient samples. PCR amplification targeting 16S rRNA gene was performed on DNA extracted from 57 cases including specimens from epidural abscesses, vertebral, and disc biopsies. Positive samples were directly sequenced. MRI findings demonstrated that disc destruction and inflammation were the major imaging features of suspected pyogenic spondylodiscitis cases, as 44 cases showed such features. The most common site of infection was the lumbar spine (66.7%), followed by thoracic spine (19%), the sacroiliac joint (9.5%), and lumbar-thoracic spine (4.8%) regions. A total of 21 samples amplified the 16S rRNA-PCR product. Sanger sequencing of the PCR products identified the following bacteriological agents: Mycobacterium tuberculosis (n = 9; 42.9%), Staphylococcus aureus (n = 6; 28.5%), Mycobacterium abscessus (n = 5; 23.8%), and Mycobacterium chelonae (n = 1; 4.8%). 36 samples displayed no visible 16S rRNA PCR signal, which suggested that non-bacterial infectious agents (e.g., fungi) or non-infectious processes (e.g., inflammatory, or neoplastic) may be responsible for some of these cases. The L3–L4 site (23.8%) was the most frequent site of infection. Single disc/vertebral infection were observed in 9 patients (42.85%), while 12 patients (57.15%) had 2 infected adjacent vertebrae. Elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) inflammatory markers were noted in majority of the patients. In conclusion, microbiological methods and MRI findings are vital components for the proper diagnosis of pyogenic spondylodiscitis. Our findings suggest that molecular methods such as clinical application of 16S rRNA PCR and sequencing may be useful as adjunctive diagnostic tools for pyogenic spondylodiscitis. The rapid turnaround time of 16S rRNA PCR and sequencing submission and results can potentially decrease the time to diagnosis and improve the therapeutic management and outcome of these infections. Although S. aureus and M. tuberculosis were the most common causes of pyogenic spinal infections in this study, other infectious agents and non-infectious etiologies should be considered. Based on study results, we advise that antibiotic therapy should be initiated after a definitive etiological diagnosis.

Iatrogenic Vascular Injury Occurring during Discectomy in a Spondylodiscitis Patient

All iatrogenic vascular injury occurring during discectomy is a rare complication, but fatal if not immediately diagnosed. When a vascular injury is highly suspected during discectomy, immediate vascular evaluation is needed even vital signs are stable during and immediately after the operation. We describe a case of iatrogenic abdominal aortic injury that occurred during discectomy in a spondylodiscitis patient, which was treated by endovascular repair.

Posterior Titanium Screw Fixation without Debridement of Infected Tissue for the Treatment of Thoracolumbar Spontaneous Pyogenic Spondylodiscitis

Study Design

Retrospective study.

Purpose

The aim of our study was to analyze the safety and effectiveness of posterior pedicle screw fixation for treatment of pyogenic spondylodiscitis (PSD) without formal debridement of the infected tissue.

Overview of Literature

Posterior titanium screw fixation without formal debridement of the infected tissue and anterior column reconstruction for the treatment of PSD is still controversial.

Methods

From March 2008 to June 2013, 18 patients with PSD underwent posterior titanium fixation with or without decompression, according to their neurological deficit. Postero-lateral fusion with allograft transplantation alone or bone graft with both the allogenic bone and the autologous bone was also performed. The outcome was assessed using the visual analogue scale (VAS) for pain and the Frankel grading system for neurological status. Normalization both of C-reactive protein (CRP) and erythrocyte sedimentation rate was adopted as criterion for discontinuation of antibiotic therapy and infection healing. Segmental instability and fusion were also analyzed.

Results

At the mean follow-up time of 30.16 months (range, 24–53 months), resolution of spinal infection was achieved in all patients. The mean CRP before surgery was 14.32±7.9 mg/dL, and at the final follow-up, the mean CRP decreased to 0.5±0.33 mg/dL (p <0.005). Follow-up computed tomography scan at 12 months after surgery revealed solid fusion in all patients. The VAS before surgery was 9.16±1.29 and at the final follow-up, it improved to 1.38±2.03, which was statistically significant (p <0.05). Eleven patients out of eighteen (61.11%) with initial neurological impairment had an average improvement of 1.27 grades at the final follow-up documented with the Frankel grading system.

Conclusions

Posterior screw fixation with titanium instrumentation was safe and effective in terms of stability and restoration of neurological impairment. Fixation also rapidly reduced back pain.

Is Biopsying the Paravertebral Soft Tissue as Effective as Biopsying the Disk or Vertebral Endplate? 10-Year Retrospective Review of CT-Guided Biopsy of Diskitis-Osteomyelitis

OBJECTIVE

The purpose of this study was to determine whether there is a difference in biopsying bone (endplate), disk, or paravertebral soft tissue to culture the pathogenic organism causing diskitis-osteomyelitis.

MATERIALS AND METHODS

A retrospective review was conducted of 111 spinal biopsies performed between 2002 and 2011. Pathologic examination was used as the reference standard for detecting diskitis-osteomyelitis. Microbiologic yield, sensitivity, and specificity were calculated. The yields for different groups were compared by use of Fisher exact test. The analysis was repeated with biopsy samples from patients not being treated with antibiotics at the time of biopsy.

RESULTS

A total of 122 biopsy specimens were obtained from 111 spinal biopsy procedures on 102 patients. Overall, 27 (22%) biopsies were performed on the endplate-disk, 61 (50%) on the disk only, and 34 (28%) on paravertebral soft tissue only. The microbiologic yield was 36% for all biopsies, 19% for endplate-disk biopsies, 39% for disk-only biopsies, and 44% for soft-tissue biopsies. The sensitivity and specificity of the microbiologic results for all specimens were 57% and 89%; endplate-disk, 38% and 86%; disk only, 57% and 89%; and paravertebral soft tissue, 68% and 92%. There was no statistically significant difference between the yields of the endplate-disk, disk-only, and paravertebral soft-tissue biopsies.

CONCLUSION

Paravertebral soft-tissue changes, when present, may be considered a viable target for biopsy in cases of diskitis-osteomyelitis, even in the absence of a paravertebral abscess.