Fawaz Siddiqi

Spontaneous chronic spinal subdural hematoma associated with spinal arachnoiditis and syringomyelia.

Spontaneous chronic spinal subdural hematoma is rare. We describe a case of spontaneous chronic spinal subdural hematoma associated with arachnoiditis and syringomyelia in a 76-year old woman who presented with a 14-year history of progressive myelopathy. MRI scan revealed a thoraco-lumbar subdural cystic lesion and a thoracic syrinx. The patient underwent thoracic laminectomy and decompression of the lesion, which was a subdural hematoma. A myelotomy was performed to drain the syrinx. Pathological examination revealed features consistent with chronic subdural membrane. This report attempts to elucidate the pathogenesis of chronic spinal subdural hematoma. We discuss possible etiological factors in light of the current literature and pathogenesis of both spinal subdural hematoma and syrinx formation.

Influence of postoperative sagittal balance and spinopelvic parameters on the outcome of patients surgically treated for degenerative lumbar spondylolisthesis

OBJECTIVE The object of this study was to determine the association between postoperative sagittal spinopelvic alignment and patient-rated outcome measures following decompression and fusion for lumbar degenerative spondylolisthesis. METHODS The authors identified a consecutive series of patients who had undergone surgery for lumbar degenerative spondylolisthesis between 2008 and 2012, with an average follow-up of 3 years (range 1-6 years). Surgery was performed to address the clinical symptoms of spinal stenosis, not global sagittal alignment. Sagittal alignment was only assessed postoperatively. Patients were divided into 2 groups based on a postoperative sagittal vertical axis (SVA) < 50 mm (well aligned) or ≥ 50 mm (poorly aligned). Baseline demographic, procedure, and outcome measures were compared between the groups. Postoperative outcome measures and postoperative spinopelvic parameters were compared between groups using analysis of covariance. RESULTS Of the 84 patients included in this study, 46.4% had an SVA < 50 mm. Multiple levels of spondylolisthesis (p = 0.044), spondylolisthesis at the L3-4 level (p = 0.046), and multiple levels treated with fusion (p = 0.028) were more common among patients in the group with an SVA ≥ 50 mm. Patients with an SVA ≥ 50 mm had a worse SF-36 physical component summary (PCS) score (p = 0.018), a worse Oswestry Disability Index (ODI; p = 0.043), and more back pain (p = 0.039) than those with an SVA < 50 mm after controlling for multiple levels of spondylolisthesis and multilevel fusion. The spinopelvic parameters differing between the < 50-mm and ≥ 50-mm groups included lumbar lordosis (LL; 56.4° ± 4.7° vs 49.8° ± 4.3°, respectively, p = 0.040) and LL < pelvic incidence ± 9° (51% vs 23.1%, respectively, p = 0.013) after controlling for type of surgical procedure. CONCLUSIONS Data in this study revealed that patient-rated outcome is influenced by the overall postoperative sagittal balance as defined by the SVA.

Treatment of thoracolumbar burst fractures: extended follow-up of a randomized clinical trial comparing orthosis versus no orthosis

OBJECTIVE A multicenter, prospective, randomized equivalence trial comparing a thoracolumbosacral orthosis (TLSO) to no orthosis (NO) in the treatment of acute AO Type A3 thoracolumbar burst fractures was recently conducted and demonstrated that the two treatments following an otherwise similar management protocol are equivalent at 3 months postinjury. The purpose of the present study was to determine whether there was a difference in long-term clinical and radiographic outcomes between the patients treated with and those treated without a TLSO. Here, the authors present the 5- to 10-year outcomes (mean follow-up 7.9 ± 1.1 years) of the patients at a single site from the original multicenter trial. METHODS Between July 2002 and January 2009, a total of 96 subjects were enrolled in the primary trial and randomized to two groups: TLSO or NO. Subjects were enrolled if they had an AO Type A3 burst fracture between T-10 and L-3 within the previous 72 hours, kyphotic deformity < 35°, no neurological deficit, and an age of 16-60 years old. The present study represents a subset of those patients: 16 in the TLSO group and 20 in the NO group. The primary outcome measure was the Roland Morris Disability Questionnaire (RMDQ) score at the last 5- to 10-year follow-up. Secondary outcome measures included kyphosis, satisfaction, the Numeric Rating Scale for back pain, and the 12-Item Short-Form Health Survey (SF-12) Mental and Physical Component Summary (MCS and PCS) scores. In the original study, outcome measures were administered at admission and 2 and 6 weeks, 3 and 6 months, and 1 and 2 years after injury; in the present extended follow-up study, the outcome measures were administered 5-10 years postinjury. Treatment comparison between patients in the TLSO group and those in the NO group was performed at the latest available follow-up, and the time-weighted average treatment effect was determined using a mixed-effects model of longitudinal regression for repeated measures averaged over all time periods. Missing data were assumed to be missing at random and were replaced with a set of plausible values derived using a multiple imputation procedure. RESULTS The RMDQ score at 5-10 years postinjury was 3.6 ± 0.9 (mean ± SE) for the TLSO group and 4.8 ± 1.5 for the NO group (p = 0.486, 95% CI -2.3 to 4.8). Average kyphosis was 18.3° ± 2.2° for the TLSO group and 18.6° ± 3.8° for the NO group (p = 0.934, 95% CI -7.8 to 8.5). No differences were found between the NO and TLSO groups with time-weighted average treatment effects for RMDQ 1.9 (95% CI -1.5 to 5.2), for PCS -2.5 (95% CI -7.9 to 3.0), for MCS -1.2 (95% CI -6.7 to 4.2) and for average pain 0.9 (95% CI -0.5 to 2.2). CONCLUSIONS Compared with patients treated with a TLSO, patients treated using early mobilization without orthosis maintain similar pain relief and improvement in function for 5-10 years.

Influence of graft size on spinal instability with anterior cervical plate fixation following in vitro flexion-distraction injuries

BACKGROUND CONTEXT Anterior cervical discectomy and fusion with plating (ACDFP) is commonly used for the treatment of distractive-flexion cervical spine injuries. Despite the prevalence of ACDFP, there is little biomechanical evidence for graft height selection in the unstable trauma scenario. PURPOSE This study aimed to investigate whether changes in graft height affect the kinematics of instrumented ACDFP C5-C6 motion segments in the context of varying degrees of simulated facet injuries. STUDY DESIGN In vitro cadaveric biomechanical study was used as study design. METHODS Seven C5-C6 motion segments were mounted in a custom spine simulator and taken through flexibility testing in axial rotation, lateral flexion, and flexion-extension. Specimens were first tested intact, followed by a standardized injury model (SIM) for a unilateral facet perch at C5-C6. The stability of the ACDFP approach was then examined with three graft heights (computed tomography-measured disc space height, disc space height undersized by 2.5 mm, and disc space height oversized by 2.5 mm) within three increasing unstable injuries (SIM, an added unilateral facet fracture, and a simulated bilateral facet dislocation injury). RESULTS In all motions, regardless of graft size, ACDFP reduced range of motion (ROM) from the SIM state. For flexion-extension, the oversized graft had a larger decrease in ROM compared with the other graft sizes (p<.05). Between graft sizes and injury states, there were a number of interactions in axial rotation and lateral flexion, where specifically in the most severe injury, the undersized graft had a larger decrease in ROM than the other two sizes (p<.05). CONCLUSIONS This study found that graft size did affect the kinematic stability of ACDFP in a series of distractive-flexion injuries; the undersized graft resulted in both facet overlap and locking of the uncovertebral joints leading to decreased ROM in lateral bending and axial rotation, whereas an oversized graft provided larger ROM decreases in flexion-extension. As such, a graft that engages the uncovertebral joint may be more advantageous in providing a rigid environment for fusion with ACDFP.

Systemic inflammatory response syndrome in patients with spinal cord injury: does its presence at admission affect patient outcomes?

OBJECT The object in this study was to determine whether the presence of systemic inflammatory response syndrome (SIRS) in patients with traumatic spinal cord injury (SCI) on admission is related to subsequent clinical outcome in terms of length of stay (LOS), complications, and mortality. METHODS The authors retrospectively reviewed the charts of 193 patients with acute traumatic SCI who had been hospitalized at their institution between 2006 and 2012. Patients were excluded from analysis if they had insufficient SIRS data, a cauda equina injury, a previous SCI, a preexisting neurological condition, or a condition on admission that prevented appropriate neurological assessment. Complications were counted only once per patient and were considered minor if they were severe enough to warrant treatment and major if they were life threatening. Demographics, injury characteristics, and outcomes were compared between individuals who had 2 or more SIRS criteria (SIRS+) and those who had 0 or 1 SIRS criterion (SIRS-) at admission. Multivariate logistic regression (enter method) was used to determine the relative contribution of SIRS+ at admission in predicting the outcomes of mortality, LOS in the intensive care unit (ICU), hospital LOS, and at least one major complication during the acute hospitalization. The American Spinal Injury Association Impairment Scale grade and patient age were included as covariates. RESULTS Ninety-three patients were eligible for analysis. At admission 47.3% of patients had 2 or more SIRS criteria. The SIRS+ patients had higher Injury Severity Scores (24.3 ±10.6 vs. 30.2 ±11.3) and a higher frequency of both at least one major complication during acute hospitalization (26.5% vs. 50.0%) and a fracture-dislocation pattern of injury (26.5% vs. 59.1%) than the SIRS- patients (p < 0.05 for each comparison). The SIRS+ patients had a longer median hospital stay (14 vs 18 days) and longer median ICU stay (0 vs. 5 days). However, mortality was not different between the groups. Having SIRS on admission predicted an ICU LOS > 10 days, hospital LOS > 25 days, and at least one complication during the acute hospitalization. CONCLUSIONS A protocol to identify SCI patients with SIRS at admission may be beneficial with respect to preventing adverse outcomes and decreasing hospital costs.

Obesity and spinal epidural lipomatosis in cauda equina syndrome

BACKGROUND CONTEXT Although lumbar disc herniations are common, only a small portion of these herniations lead to cauda equina syndrome (CES), which is an uncommon but debilitating disorder. Why some patients with herniation develop CES, when most do not, remains unknown. Preexisting subclinical epidural lipomatosis may limit canal space such that an otherwise benign herniation causes CES. PURPOSE This study determines whether patients with an acute disc herniation and CES have a greater body mass index (BMI) and greater quantity of epidural fat compared with control subjects with non-CES symptomatic lumbar herniated discs. STUDY DESIGN/SETTING A retrospective case-control series at a university-based level-1 trauma center was carried out. PATIENT SAMPLE There were 33 CES and 66 control subjects identified from a prospectively maintained database of patients who underwent surgical management for a lumbar disc herniation between 2007 and 2012. Each CES case had two non-CES control patients matched by gender and age within 5 years except 5 CES cases that matched only one non-CES control. OUTCOME MEASURES The outcome measures included weight, height, age, gender, and BMI. Radiographic outcome measures included the proportion of lumbar spinal canal occupied by fat and herniated disc on preoperative magnetic resonance imaging. METHODS Patient charts and preoperative radiographs were retrospectively reviewed. For each patient, a blinded reviewer determined the proportion of lumbar spinal canal occupied by fat, and the maximal proportion of the canal occupied by herniated material at the involved level. Patient demographics and radiographic measures were compared between CES and control groups using chi-square or Student t tests. A second blinded reviewer re-assessed a series of radiographs, and the intraobserver variability was determined by Spearman correlation. Logistic regression was used to model the preoperative factors associated with having an acute disc herniation and CES. RESULTS The CES cases had higher BMI (31.8 kg/m2, 95% confidence interval [CI] 29.5-34.0 vs. 28.1 kg/m2, 95% CI 26.7-29.5 in controls; p=.007), focally narrower canals (14.6 mm, 95% CI 13.8-15.3 mm vs. 16.4 mm, 95% CI 15.4-17.3 mm in controls; p=.003), and a greater percentage of spinal canal occupied by epidural fat (31.3%, 95% CI 26.1%-36.6% vs. 21.9%, 95% CI 18.7%-25.1% in controls; p=.003) and herniated disc material (54.5%, 95% CI 46.9%-62.0% vs. 34.4%, 95% CI 30.3%-38.5% in controls; p<.0001). Logistic regression confirmed canal width at the involved level, BMI, amount of canal occupied disc, and proportion of canal occupied by fat as independent predictors of having an acute disc herniation and CES. CONCLUSIONS Obesity is a risk factor for CES from disc herniation. The CES cases also had a greater amount of herniated material, focally narrower canal, and larger epidural fat deposits. The latter may be the mechanism linking obesity with CES.

Primary Clear Cell Chondrosarcoma of Thoracic Spine: A Rare Tumor in an Uncommon Location.

Clear cell chondrosarcoma is a rare cartilaginous tumor that arises commonly in the epiphyses of the proximal femur or humerus. Spinal involvement is extremely rare, but when present, it most frequently involves the thoracic spine. Clear cell chondrosarcoma is rarely reported in thoracic spine. We report a case of a 70-year-old man with clear cell chondrosarcoma of the T7-8 thoracic spine. Gross en bloc resection of T6-8 vertebral bodies with reconstruction and fusion followed by radiotherapy were performed.

Intradural Extramedullary Spinal Cord Metastasis of the Prostate: A Case Presentation and Review of the Literature.

Prostate cancer is associated with vertebral metastasis in up to 10% of patients; however, intradural spinal cord metastases (ISCM) are much less frequent. We present the clinical and histopathological findings of a patient with ISCM arising from prostate. A PubMed literature search for ISCM from the prostate yielded a total of nine additional cases. ISCM of the prostate occurs at a late stage of systemic disease and the prognosis is generally poor. Decompressive surgery followed by adjuvant radiation therapy may help reduce intractable pain and stabilize neurological symptoms, thereby improving quality of life.