Lumbar facet cyst tuberculosis: a rare cause of cauda equina compression. Illustrative case.

BACKGROUND: Spinal tuberculosis may present in atypical form to involve only the posterior spinal element with relative sparing of the anterior vertebral body and intervertebral disc. Recognition of this unusual pattern is important to avoid delay in diagnosis and treatment. OBSERVATIONS: The authors report a case of a 59-year-old woman with right-sided radiculopathy and motor weakness. Her lumbosacral magnetic resonance imaging showed a large heterogeneous cyst arising from the right L4-5 facet joint. Laminectomy with excision of the cyst was performed. During surgery, the cyst contained cheese-like material that, on histopathological examination, revealed focal aggregates of tuberculous granuloma. Postoperatively, the patient recovered remarkably with no interval development of instability or any deformity. LESSONS: Facet cyst tuberculosis is rare but should be considered in the differential diagnosis in patients coming from endemic regions. Laminectomy with excision of the cyst along with concurrent antitubercular chemotherapy is a safe and durable treatment option in this case.

Surgical management of an extensive spinal epidural abscess: illustrative cases.

BACKGROUND: Extensive spinal epidural abscesses (SEAs) occupying three or more spinal regions are rare. This study aimed to address the key dilemma of surgical treatment for holospinal epidural abscesses, i.e., to determine the required scope of surgery and minimize surgical trauma with adequate purulent drainage. OBSERVATIONS: Two patients with extensive SEAs were treated at the Neurosurgery Department of the Central Hospital of Ministry of Internal Affairs of Ukraine from 2018 to 2020. Both patients had a neurological deficit and general inflammatory response syndrome. Spinal magnetic resonance examinations were performed, showing that the first and second patients had extensive SEAs at T11/S1 and C2/L1, respectively. Both underwent minimally invasive abscess drainage via intra- and translaminar access at the most caudal point using an epidural silicone catheter in the cranial direction along the entire length of the abscess. LESSONS: To achieve the key goal of extensive SEA treatment, i.e., to prevent the development of a persistent neurological deficit, immediate effective spinal canal decompression should be performed. Access method and scope should meet the requirements of spinal canal decompression and purulent content aspiration to the greatest possible extent while inducing minimal trauma.

Gout in the thoracic spine causing acute paraplegia: illustrative case.

BACKGROUND: Although spinal involvement by gout is not uncommon, spinal gout leading to symptomatic spinal cord compression in the thoracic spine is very rare and poses a diagnostic challenge by mimicking symptoms of more common diagnoses such as epidural abscess and malignancy. An even more unique presentation is spinal gout causing thoracic cord compression leading to acute paraplegia. OBSERVATIONS: The authors present an illustrative case of a 35-year-old man with thoracic spinal compression by tophaceous gout who developed rapid progression to complete paraplegia over a 5-day period. Magnetic resonance imaging of the thoracic spine revealed a cystic-appearing lesion within the dorsal extradural space of the lower thoracic spine extending from T8 to T10 accompanied by compression of the spinal cord. An emergent T9-10 laminectomy was performed, and the occupying lesion in the thoracic spine was resected. The diagnosis of spinal tophaceous gout was made by pathological examination. LESSONS: Although varying clinical manifestations of spinal gout have been reported in the literature, the patient's age and the rapid progression to complete paraplegia over a 5-day period reveals a unique presentation that broadens understanding of the manner in which this condition can present and allow more rapid diagnosis and treatment.

Readmission after spinal epidural abscess management in urban populations: a bi-institutional study.

OBJECTIVE: The incidence of spinal epidural abscess (SEA) is rising, yet there are few reports discussing readmission rates or predisposing factors for readmission after treatment. The aims of the present study were to determine the rate of 90-day readmission following medical or surgical treatment of SEA in an urban population, identify patients at increased risk for readmission, and delineate the principal causes of readmission. METHODS: Neurosurgery records from two large urban institutions were reviewed to identify patients who were treated for SEA. Patients who died during admission or were discharged to hospice were excluded. Univariate analysis was performed using chi-square and Student t-tests to identify potential predictors of readmission. A multivariate logistic regression model, controlled for age, body mass index, sex, and institution, was used to determine significant predictors of readmission. RESULTS: Of 103 patients with identified SEA, 97 met the inclusion criteria. Their mean age was 57.1 years, and 56 patients (57.7%) were male. The all-cause 90-day readmission rate was 37.1%. Infection (sepsis, osteomyelitis, persistent abscess, bacteremia) was the most common cause of readmission, accounting for 36.1% of all readmissions. Neither pretreatment neurological deficit (p = 0.16) nor use of surgical versus medical management (p = 0.33) was significantly associated with readmission. Multivariate analysis identified immunocompromised status (p = 0.036; OR 3.5, 95% CI 1.1-11.5) and hepatic disease (chronic hepatitis or alcohol abuse) (p = 0.033; OR 2.9, 95% CI 1.1-7.7) as positive predictors of 90-day readmission. CONCLUSIONS: The most common indication for readmission was persistent infection. Readmission was unrelated to baseline neurological status or management strategy. However, both hepatic disease and baseline immunosuppression significantly increased the odds of 90-day readmission after SEA treatment. Patients with these conditions may require closer follow-up upon discharge to reduce overall morbidity and hospital costs associated with SEA.

Late-onset neurological deficits induced by proximal adjacent segment degeneration related to severe post-tuberculous kyphotic deformities of the spine: a series of 7 cases and surgical correction concept.

OBJECTIVE: Late-onset neurological deficits are a rare complication of spinal tuberculosis that may be caused by proximal adjacent segment degeneration (ASD) above the kyphus. The objective of this study was to report several cases of neurological deficits due to proximal ASD in patients with post-tuberculous kyphotic deformity and discuss the characteristics of the authors' corrective surgical technique. METHODS: The inclusion criteria in this study were severe angular kyphosis due to a post-tuberculous kyphotic deformity and a late-onset neurological deficit. The cause of these deficits was related to a lesion in the proximal cephalad portion of the kyphotic deformity. Surgical intervention, including decompression and compromised restoration of the sagittal imbalance, was performed in all patients. Preoperative surgical planning with a radiological evaluation included CT, plain radiograph, and MRI studies. Clinical outcomes were evaluated using the American Spinal Injury Association Impairment Scale and the Oswestry Disability Index (ODI). RESULTS: The main goal of our surgical technique was the correction of sagittal malalignment by positioning the patient's head above the kyphotic deformity on the sagittal plane, excluding aggressive osteotomy. The neurological symptoms showed immediate improvements postoperatively, except in 1 patient. Compared to the preoperative value of 66.9, the mean ODI score improved to 42.6 at the final follow-up for all patients. Preoperatively, the mean values of the angles of deformity and the sagittal vertical axis were 99.7° and 157.7 mm, respectively, and decreased to 75.3° and 46.0 mm, respectively, at the final follow-up. No major complications were observed, and the patients' self-satisfaction was high with respect to both cosmetic and functional outcomes. CONCLUSIONS: Clinicians should be aware of the degeneration of the vertebrae above the kyphotic segment in patients with post-tuberculosis deformity. Successful neurological recovery and compromised sagittal balance could be obtained by using our "head on kyphus" surgical concept.

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.

Compressive cervical pannus formation in a patient after 2-level disc arthroplasty: a rare complication treated with posterior instrumented fusion.

Cervical disc arthroplasty (CDA) has received widespread attention as an alternative to anterior fusion due to its similar neurological and functional improvement, with the advantage of preservation of segmental motion. As CDA becomes more widely implemented, the potential for unexpected device-related adverse events may be identified. The authors report on a 48-year-old man who presented with progressive neurological deficits 3 years after 2-level CDA was performed. Imaging demonstrated periprosthetic osteolysis of the vertebral endplates at the CDA levels, with a heterogeneously enhancing ventral epidural mass compressing the spinal cord. Diagnostic workup for infectious and neoplastic processes was negative. The presumptive diagnosis was an inflammatory pannus formation secondary to abnormal motion at the CDA levels. Posterior cervical decompression and instrumented fusion was performed without removal of the arthroplasty devices or the ventral epidural mass. Postoperative imaging at 2 months demonstrated complete resolution of the compressive pannus, with associated improvement in clinical symptoms. Follow-up MRI at > 6 months showed no recurrence of the pannus. At 1 year postoperatively, CT scanning revealed improvement in periprosthetic osteolysis. Inflammatory pannus formation may be an unexpected complication of abnormal segmental motion after CDA. This rare etiology of an epidural mass associated with an arthroplasty device should be considered, in addition to workup for other potential infectious or neoplastic mass lesions. In symptomatic individuals, compressive pannus lesions can be effectively treated with fusion across the involved segment without removal of the device.

Bartonella henselae infection presenting as cervical spine osteomyelitis: case report.

Bartonella henselae is a gram-negative bacillus implicated in cat-scratch disease. Cat-scratch disease is usually self-limiting and results in local lymphadenopathy. In rare circumstances, patients may develop endocarditis, neuroretinitis, or osteomyelitis. Osteomyelitis of the cervical spine is exceedingly rare, especially in the pediatric population, and to date there have been only 4 previously reported cases of cervical spine osteomyelitis caused by B. henselae, all of which were treated surgically. In this article, the authors report the case of a 7-year-old boy who presented with neck swelling and was found to have a C2-4 paravertebral B. henselae abscess with osteomyelitis of C-3 and epidural extension. To the authors' knowledge, this represents the first case in the literature of a cervical spine B. henselae infection managed conservatively.

Delayed osteomyelitis resulting from an extension injury of the cervical spine: case report.

Osteomyelitis of the cervical spine is an exceedingly rare lesion in pediatric practice and is caused by a variety of mechanisms. The authors present a case in which cervical osteomyelitis presented in a delayed manner after the patient experienced a stable cervical extension injury at the C4-5 level. On review of the original images, the authors noted a likely perforation in the retropharyngeal space. This case highlights the risk of retropharyngeal injury in cervical trauma, with the seldom-seen complication of osteomyelitis as a result.

Thoracic osteomyelitis and epidural abscess formation due to cat scratch disease: case report.

Osteomyelitis of the spine with associated spinal epidural abscess represents an uncommon entity in the pediatric population, requiring prompt evaluation and diagnosis to prevent neurological compromise. Cat scratch disease, caused by the pathogen Bartonella henselae, encompasses a wide spectrum of clinical presentations; however, an association with osteomyelitis and epidural abscess has been reported in only 4 other instances in the literature. The authors report a rare case of multifocal thoracic osteomyelitis with an epidural abscess in a patient with a biopsy-proven pathogen of cat scratch disease. A 5-year-old girl, who initially presented with vague constitutional symptoms, was diagnosed with cat scratch disease following biopsy of an inguinal lymph node. Despite appropriate antibiotics, she presented several weeks later with recurrent symptoms and back pain. Magnetic resonance imaging revealed 2 foci of osteomyelitis at T-8 and T-11 with an associated anterior epidural abscess from T-9 to T-12. Percutaneous image-guided vertebral biopsy revealed B. henselae by polymerase chain reaction analysis, and she was treated conservatively with doxycycline and rifampin with favorable clinical outcome.

Acute spinal cord injury associated with multilevel pediatric idiopathic intervertebral disc calcification: case report.

Pediatric idiopathic intervertebral disc calcification (PIIVDC) is a rare condition; most cases are reported to be selflimited with conservative management. In this study, we describe a case of PIIVDC presenting with acute incomplete spinal cord injury with Brown-Séquard-plus syndrome that was treated with surgery and demonstrate the subsequent rehabilitation time course.

Incidence of microbiological contamination of local bone autograft used in posterior lumbar interbody fusion and its association with postoperative spinal infection.

OBJECTIVE: The aim of this study was to examine the results of microbiological cultures from local bone autografts used in posterior lumbar interbody fusion (PLIF) and to identify their association with postoperative spinal infection. METHODS: The authors retrospectively evaluated cases involving 328 patients who had no previous spinal surgeries and underwent PLIF for degenerative diseases with a minimum 1-year follow-up. Local bone was obtained during laminectomy, and microbiological culture was performed immediately prior to bone grafting. The associations between culture results from local bone autografts and postoperative spinal infections were evaluated. RESULTS: The contamination rate of local bone was 4.3% (14 of 328 cases). Coagulase-negative Staphylococcus (29%) was the most common contaminant isolated, followed by Streptococcus species and methicillin-sensitive Staphylococcus aureus. Of 14 patients with positive culture results, 5 (35.7%) had postoperative spinal infections and were treated with intravenous antibiotics for a minimum of 4 weeks. One of these 5 patients also underwent reoperation for debridement during this 4-week period. Regardless of the microbiological culture results, the infection rate after PLIF with local bone autograft was 2.4% (8 of 328 cases), with 5 (62.5%) of 8 patients showing positive results on autograft culture. CONCLUSIONS: The incidence of contamination of local bone autograft during PLIF was considerable, and positive culture results were significantly associated with postoperative spinal infection. Special attention focused on the preparation of local bone for autograft and its microbiological culture will be helpful for the control of postoperative spinal infection.

Single-level lumbar pyogenic spondylodiscitis treated with mini-open anterior debridement and fusion in combination with posterior percutaneous fixation via a modified anterior lumbar interbody fusion approach.

OBJECT: This study evaluated the efficacy and safety of mini-open anterior debridement and lumbar interbody fusion in combination with posterior percutaneous fixation for single-level lumbar pyogenic spondylodiscitis. METHODS: This is a retrospective study. Twenty-two patients with single-level lumbar pyogenic spondylodiscitis underwent mini-open anterior debridement and lumbar interbody fusion in combination with posterior percutaneous fixation via a modified anterior lumbar interbody fusion (ALIF) approach. Patients underwent follow-up for 24 to 38 months. Clinical data, etiological examinations, operative time, intraoperative blood loss, American Spinal Injury Association (ASIA) grade, Japanese Orthopaedic Association (JOA) lumbar function score, visual analog scale (VAS) score, Oswestry Disability Index (ODI), postoperative complications, and the bony fusion rate were recorded. RESULTS: The mean operative time was 181.1 ± 22.6 minutes (range 155-240 minutes). The mean intraoperative blood loss was 173.2 ± 70.1 ml (range 100-400 ml). Infection was found in lumbar vertebrae L2-3, L3-4, and L4-5 in 2, 6, and 14 patients, respectively. Bacterial cultures were positive in 15 patients, including 4 with Staphylococcus aureus, 6 with Staphylococcus epidermidis, 4 with Streptococcus, and 1 with Escherichia coli. Postoperative complications included urinary retention, constipation, and numbness in the thigh in 5, 3, and 2 patients, respectively. Compared with before surgery, the VAS scores and ODI were significantly lower at the final follow-up, the JOA scores were significantly higher, and the ASIA grades had improved. All patients achieved good intervertebral bony fusion. CONCLUSIONS: Mini-open anterior debridement and lumbar interbody fusion in combination with posterior percutaneous fixation via a modified ALIF approach results in little surgical trauma and intraoperative blood loss, acceptable postoperative complications, and is effective and safe for the treatment of single-level lumbar pyogenic spondylodiscitis. This approach could be an alternative to the conventional open surgery.

Vertebral osteolytic defect due to cellulose particles derived from gauze fibers after posterior lumbar interbody fusion.

Vertebral cystic lesions may be observed in pseudarthroses after lumbar fusion surgery. The authors report a rare case of pseudarthrosis after spinal fusion, accompanied by an expanding vertebral osteolytic defect induced by cellulose particles. A male patient originally presented at the age of 69 years with leg and low-back pain caused by a lumbar isthmic spondylolisthesis. He underwent a posterior lumbar interbody fusion, and his neurological symptoms and pain resolved within a year but recurred 14 months after surgery. Radiological imaging demonstrated a cystic lesion on the inferior endplate of L-5 and the superior endplate of S-1, which rapidly enlarged into a vertebral osteolytic defect. The patient underwent revision surgery, and his low-back pain resolved. A histopathological examination demonstrated foreign body-type multinucleated giant cells, containing 10-µm particles, in the sample collected just below the defect. Micro-Fourier transform infrared spectroscopy revealed that the foreign particles were cellulosic, presumably originating from cotton gauze fibers that had contaminated the interbody cages used during the initial surgery. Vertebral osteolytic defects that occur after interbody fusion are generally presumed to be the result of infection. This case suggests that some instances of vertebral osteolytic defects may be aseptically induced by foreign particles. Hence, this possibility should be carefully considered in such cases, to help prevent contamination of the morselized bone used for autologous grafts by foreign materials, such as gauze fibers.

Soft-tissue defects after spinal instrumentation in 5 children: risk factors, management strategies, and outcomes.

OBJECT: Wound-related complications following complex posterior spine procedures in children may result in the need for serial debridements and may place spinal instrumentation at risk. In this study, the authors review their experience with the management of soft-tissue defects from spinal instrumentation in 5 high-risk pediatric patients. The use of various rotational and transpositional flaps in the management of these complicated cases is discussed, as well as their outcomes. METHODS: The authors retrospectively reviewed the medical records of 5 patients who returned to the Neuro-Spine service at Texas Children's Hospital for erosion of spinal instrumentation through the skin between September 1, 2007, and October 31, 2012. Patient demographics and clinical and operative data were recorded. RESULTS: Risk factors such as young age (1 case), poor nutritional status (1 case), multiple previous surgeries (3 cases), severe neurological deficits (2 cases), and history of radiation therapy for malignancy (2 cases) were noted in the 5 patients. The paraspinous flap (4 cases) was the mainstay of the treatment. Follow-up ranged from 7.5 to 17.5 months (mean 11 ± 4.2 months). One of the patients required more than 1 procedure for revision of the wound. Cultures were positive in 2 of the 5 cases. Spinal instrumentation was removed in 3 of the 5 cases; however, in all 3 of the cases there was evidence of delayed instability that developed after the removal of spinal instrumentation. CONCLUSIONS: The use of local tissue flaps is safe and efficacious for treatment of posterior wound complications due to spinal instrumentation in children. Removal of spinal instrumentation should be avoided due to the development of delayed instability. Highly vascularized tissue is used to speed healing, clear bacteria, and eliminate dead space, obviating the need to remove contaminated spinal instrumentation.

Computed tomography-guided percutaneous biopsy for vertebral osteomyelitis: a department's experience.

OBJECT: Vertebral osteomyelitis has been reported to occur in approximately 0.2-2 cases per 100,000 annually. Elevated laboratory values such as erythrocyte sedimentation rate and C-reactive protein suggest inflammatory etiologies. Different imaging modalities, from radiography and CT scanning to nuclear medicine imaging and contrastenhanced MRI, can be employed to evaluate for osteomyelitis. Although MRI has a strong sensitivity and specificity for vertebral osteomyelitis, obtaining histological and microbiological samples remains the gold standard in diagnosis. Therapy can be geared toward the specific pathogen cultured, thereby preventing the need surgical intervention in the majority of cases. However, recent reports have questioned the percentage yield of image-guided percutaneous biopsy even when there is a high clinical suspicion for vertebral osteomyelitis. METHODS: After obtaining institutional review board approval, the authors performed a chart review of patients who had undergone image-guided percutaneous bone biopsies at University Hospitals Case Medical Center in Cleveland, Ohio. Data were filtered for patients in whom a biopsy sample of a vertebral body/disc was obtained. A total of 213 procedures were performed, of which clinicians indicated a concern for infection in 84, infection or neoplasm in 13, and a noninfectious etiology (the majority being neoplasms) in the remaining 116. RESULTS: Histological examination provided positive results in 25 (41.0%) of the 61 samples collected for suspected cases of osteomyelitis. Microbiology samples were less predictive, with only 16 of the 84 samples collected, or 19.0%, yielding a positive result. In 10 patients there were positive blood and/or urine cultures. Of these, 8 samples (80%) demonstrated the same pathogen identified by biopsy (for the remaining 2 positive systemic cultures, no pathogen was identified by the percutaneous intervention). In other words, half of the 16 cases that provided microbiological results from biopsy demonstrated the same results by systemic cultures. However, 89 (76.7%) of the 116 samples collected with the primary concern of neoplasm yielded results. CONCLUSIONS: Image-guided percutaneous biopsy for vertebral osteomyelitis demonstrates an extremely low probability of identifying specific microbes. Blood or urine cultures concurrently identified culprit pathogens in 50% of positive biopsy cultures. Therefore, in only 8 (9.5%) of 84 biopsies did the biopsy results provide additional information to clinicians as to the pathological microorganism present and how treatment might need to be adjusted.

Intramedullary spinal cord abscess and subsequent granuloma formation: a rare complication of vertebral osteomyelitis detected by diffusion-weighted magnetic resonance imaging.

An intramedullary spinal cord abscess, which is usually associated with discitis, is an uncommon but potentially important complication of vertebral osteomyelitis. The authors describe a rare case of an intramedullary conus medullaris abscess and lumbar osteomyelitis sparing the intervertebral discs and without discitis. The patient also developed a granuloma in the cauda equina during treatment. Diffusion-weighted MRI was useful for differentiating the granulomatous lesion from the relapse of infection. A 65-year-old immunocompetent man with moderately controlled diabetes presented with progressive lowerextremity numbness and weakness with urinary dysfunction. He had progressive paraparesis, bilateral leg paresthesia, and sphincter compromise. Magnetic resonance imaging revealed an intramedullary ring-enhanced lesion, which was hyperintense on diffusion-weighted images. The lesion, an intramedullary spinal cord abscess, was surgically drained. During antibiotic treatment, serial MRI showed an enlarging enhanced lesion in the cauda equina, and a recurrent infection was suspected. A second-look surgery confirmed the formation of a granuloma and the absence of a relapse of the abscess. Although the enhanced lesion increased in size, its intensity on diffusion-weighted images remained unchanged. After 3 months of antibiotic treatment, all enhanced lesions were diminished. An intramedullary spinal cord abscess is a rare but important complication of vertebral osteomyelitis, and it requires immediate treatment. Diffusion-weighted MRI was useful for the initial diagnosis as well as for monitoring treatment efficacy.

Diagnosis and management of primary pyogenic spinal infections in intravenous recreational drug users.

OBJECT: Primary spine infection secondary to intravenous drug abuse (IVDA) is a difficult clinical entity encountered by spine surgeons and infectious disease specialists. Patients tend to be noncompliant with the treatment and follow-up, and some continue to use IV recreational drugs even after the diagnosis of spine infection. The authors undertook this study to analyze the presentation, etiology, demographic characteristics, treatment, and outcome of primary pyogenic spinal infection in patients with IVDA as the major risk factor. METHODS: The medical records, radiology imaging, and laboratory results (white blood cell count, inflammatory markers, bacteriology cultures) of all patients with pyogenic spine infection and history of IVDA presenting to a tertiary care center from August 2005 through December 2013 were retrospectively reviewed. The department of neurosurgery database and the hospital electronic medical records of University Hospital in San Antonio were used to identify the cohort for our study. RESULTS: A total of 164 patients with spinal infection were evaluated during the study period; 102 of these patients had a history of IVDA. Their average age was 45.4 years, and only 14 (13.7%) were women. The mean laboratory values at presentation included a white blood cell count of 11.1 × 10(3) cells/µl (range 0.5-32 × 10(3) cells/µl), erythrocyte sedimentation rate (ESR) of 74 mm/hr (range 9.9-140 mm/hr), and C-reactive protein (CRP) level of 67 mg/L (range 0.1-327 mg/L). Twenty-six patients (25.4%) had an associated epidural abscess. The most common organism isolated from cultures of the bone and/or blood was methicillin-sensitive Staphylococcus aureus (MSSA), which was found in 37 cases. A close second was methicillin-resistant S. aureus (MRSA), found in 23 cases. The most commonly involved region was the lumbar spine (24 cases [57.8%]), and most patients (69.6%) had involvement of only a single level. Eighty patients were initially treated with long-term IV antibiotic therapy, and only 22 underwent surgical intervention (24 procedures). Of the latter group, 8 patients underwent laminectomy alone while 16 required some type of instrumented stabilization. Of the patients requiring stabilization procedures, 2 (12.5%) required reoperation with extension of their surgical constructs to other levels. The average follow-up was 29.7 weeks (range 6 weeks to 3 years). CONCLUSIONS: Diagnosis and management of spinal infection in patients with a history of IVDA is challenging. The data from this study show that initial laboratory values are difficult to interpret given that only a minority of these patients present with leukocytosis. Back pain was the only reliable predictor of spine infection. The authors' experience indicates that the majority of patients with spine infection and a history of IVDA can be successfully treated with IV antibiotic therapy alone.

Direct lateral retroperitoneal approach for the surgical treatment of lumbar discitis and osteomyelitis.

OBJECT: The medical management of discitis and osteomyelitis with long-term antibiotic therapy and bracing usually results in eradicated infection. Surgical management is appropriate when medical management fails and in some cases with pyogenic deformity or neurological deficit. The success of surgery depends on adequate debridement of the necrotic infected disc and vertebral body, along with anterior column reconstruction and vertebral stabilization. Debridement is typically performed via an anterior retroperitoneal approach, which can necessitate mobilization of the great vessels for proper exposure. Mobilization can be technically difficult and lead to vascular injury. The purpose of this study was to evaluate an alternative technique for the surgical treatment of lumbar discitis and osteomyelitis using a direct lateral retroperitoneal approach, which allows for thorough debridement and anterior column reconstruction while avoiding the need to mobilize the great vessels. METHODS: A retrospective chart analysis was performed for all patients who had presented with lumbar discitis and osteomyelitis and had undergone surgical management via the direct lateral retroperitoneal approach in the period from 2006 to 2013. Collected data included surgical blood loss, perioperative complications (wound infection, vascular injury, approach-related complications, and neurological injury), need for secondary procedures, microbiological and laboratory results, and efficacy of infection eradication. Imaging studies were reviewed as well. RESULTS: Ten patients, 7 male and 3 female, underwent this procedure at the authors' institution in the defined period. Average blood loss was 272 ml (range 150-800 ml, with 800 ml in the only 2-level case). There were no vascular injuries. Average follow-up was 680 days, although 4 patients did not complete the follow-up beyond 6 months. Eight patients underwent immediate posterior pedicle screw instrumentation. Two patients did not undergo posterior instrumentation, and one of these developed a kyphotic deformity that required a secondary posterior procedure. Infection was eradicated in all patients according to a history, physical examination, imaging studies, and laboratory parameters (complete blood count, erythrocyte sedimentation rate, and C-reactive protein). One patient developed a painful neuroma at the iliac crest harvest site, and one patient had a retroperitoneal hematoma. Otherwise, there were no approach-related neurological injuries or complications. Neither was there any postoperative surgical site infection. CONCLUSIONS: The direct lateral approach for the surgical treatment of lumbar discitis and osteomyelitis allows for thorough debridement and spinal reconstruction without the need to mobilize the great vessels. This technique effectively eradicated infection in all cases, with reasonable blood loss and no vascular injuries. This approach should be considered as an alternative to the open anterior approach. The authors recommend posterior instrumentation to prevent the development of kyphosis.