Arash Emami

The role of magnetic resonance imaging in acute cervical spine fractures

BACKGROUND CONTEXT The role of magnetic resonance imaging (MRI) in neurologically intact cervical spine fractures is not well defined. To our knowledge, there are no studies that clearly identify the indications for MRI in this particular scenario. Controversy remains regarding the use of MRI in at-risk patients, primarily the obtunded and elderly patients. PURPOSE The purpose of the present study was to examine the predisposing conditions where an MRI would provide additional findings that would affect management in acute cervical spine fractures. STUDY DESIGN Retrospective cohort involving radiographic and clinical review. PATIENT SAMPLE Consecutive patients with acute cervical injuries at a single institution. OUTCOME MEASURES Neurologic recovery. METHODS A review of 830 patients with cervical spinal injuries between 2006 and 2010 was performed. Clinical information was obtained for all the patients: Glasgow Coma Scale, mechanism of injury, major medical comorbidities, associated injuries, neurologic examination, neurologic symptoms, sex, age, and alertness. Two experienced fellowship-trained spine surgeons determined if the MRI study changed the management in the individual cases based on the Sub-axial Cervical Spine Injury classification system. RESULTS Ninety-nine patients with a cervical fracture were included in the final analysis: median age 54 years (interquartile range, 42 years), mean Glasgow Coma Scale 13 (standard deviation ± 3.0), 68% males, 32% females, 42% older patients (age>60 years), 30% spondylosis, 27% polytrauma, 67% alert, 28% neurologic deficit. Major medical comorbidities, prior to injury level of activity, atlantoaxial versus subaxial, and gender were not associated with changes in diagnosis and management (p>.05). Age >60 years, neurologic deficit, polytrauma status, alertness, and spondylosis were associated with having additional clinically relevant findings seen on MRI and changes in management (p<.05). The majority of the changes in management were related to MRIs illustration of the spinal cord injury and not due to an occult instability. Eighty-one percent of the changes in management were related to the depiction of the spinal cord compression seen on MRI, whereas 19% of the changes in management were related to occult instability seen on MRI. CONCLUSIONS Older age (>60 years), obtunded or temporary non-assessable status, cervical spondylosis, polytrauma, and neurologic deficit are predisposing factors for further injury found on MRI but missed on computed tomographic scan alone. These additional findings can affect the management in acute cervical spine fractures. The rational of the on-call spine surgeon to order an MRI for a cervical spine fracture is well founded and often that MRI will affect the fracture management. Magnetic resonance imaging particularly helps with better defining the type of spinal cord compression. Picking up occult instability missed on computed tomographic scan was possible with MRI but not as common.

Paraspinal Muscle Atrophy After Lumbar Spine Surgery

Paraspinal muscles are commonly affected during spine surgery. The purpose of this study was to assess the potential factors that contribute to paraspinal muscle atrophy (PMA) after lumbar spine surgery. A comprehensive review of the available English literature, including relevant abstracts and references of articles selected for review, was conducted to identify studies that reported PMA after spinal surgery. The amount of postoperative PMA was evaluated in (1) lumbar fusion vs nonfusion procedures; (2) posterior lumbar fusion vs anterior lumbar fusion; and (3) minimally invasive (MIS) posterior lumbar decompression and/or fusion vs non-MIS equivalent procedures. In total, 12 studies that included 529 patients (262 men and 267 women) were reviewed. Of these, 365 patients had lumbar fusions and 164 had lumbar decompressions. There was a significantly higher mean postoperative volumetric PMA with fusion vs nonfusion procedures (P=.0001), with posterior fusion vs anterior fusion (P=.0001), and with conventional fusions vs MIS fusions (P=.001). There was no significant difference in mean volumetric lumbar PMA with MIS decompression vs non-MIS decompression (P=.56). There was significantly higher postoperative PMA with lumbar spine fusions, posterior procedures, and non-MIS fusions.

Minimally Invasive Transforaminal Lumbar Interbody Fusion in the Outpatient Setting.

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) has been shown to have long-term clinical outcomes similar to those with open TLIF and decreased perioperative morbidity. This study assessed whether this procedure can be safely performed in outpatient settings. Ninety-six consecutive patients undergoing 1- or 2-level MIS-TLIFs were retrospectively reviewed. They were divided into inpatient and outpatient cohorts (36%). All had a minimum of 2 years of follow-up. Patient demographics, comorbidities, complications, and readmissions were examined. Early postoperative complications were stratified into wound related, infection, neurologic, implant related, and vascular injuries. Patients in the outpatient cohort were significantly younger, had lower American Society of Anesthesiologists physical status scores, and had lower Charlson Comorbidity Index scores than patients in the inpatient cohort. There were no statistically significant differences in overall postoperative complication rates, readmission rates, or final Oswestry Disability Index or visual analog scale scores between the 2 cohorts. The clinical outcomes of the outpatient TLIF procedure were similar to those of the inpatient procedure and it had an acceptable complication rate. [Orthopedics. 2016; 39(6):e1218-e1222.].

Cervical Corpectomy With Ultra-low-dose rhBMP-2 in High-risk Patients: 5-year Outcomes

Twenty-four consecutive patients with cervical spondylosis who were treated with cervical corpectomy and recombinant human bone morphogenetic protein-2 (rhBMP-2) with standalone anterior instrumentation were evaluated. Mean number of levels fused was 2.4. There were significant improvements in visual analog scale neck pain and Oswestry Disability Index scores and cervical lordosis. Cervical corpectomy with a lower dose of rhBMP-2 was found to be safe and efficacious for patients who are at a higher risk for pseudarthrosis.

Ultra-Low-Dose Recombinant Human Bone Morphogenetic Protein-2 for 3-Level Anterior Cervical Diskectomy and Fusion

This study evaluated the safety of 3-level anterior cervical diskectomy and fusion (ACDF) with ultra-low-dose recombinant bone morphogenetic protein-2 (rhBMP-2). Thirty-seven consecutive patients with cervical spondylotic myelopathy who were treated with 3-level ACDF and rhBMP-2 were evaluated. Complications such as airway or cervical swelling or hematoma were not observed. The rate of dysphagia was no different at 1, 2, and 6 months postoperatively compared with reports in the literature without rhBMP-2. There were significant improvements in VAS neck/arm pain, Oswestry Neck Disability Index, and cervical lordosis. The use of ultra-low-dose rhBMP-2 for 3-level ACDF may be efficacious for surgically addressing 3-level spondylotic myelopathy.

Incidence of Neuraxial Abnormalities Is Approximately 8% Among Patients With Adolescent Idiopathic Scoliosis: A Meta-analysis

Background Several studies have sought to address the role of routine preoperative MRI in patients with adolescent idiopathic scoliosis (AIS) undergoing deformity correction. Despite similar results regarding the prevalence of neuraxial anomalies detected on MRI, published conclusions conflict and give opposing recommendations. Lack of consensus has led to important variations in use of MRI before spinal surgery for patients with AIS. Questions/purposes This systematic review and meta-analysis of studies about patients with AIS evaluated (1) the overall proportion of neuraxial abnormalities; (2) the patient factors and curve characteristics that may be associated with abnormalities; and (3) the proportion of patients who underwent neurosurgical intervention before scoliosis surgery and the kinds of neuraxial lesions that were identified. Methods We performed a search of four electronic databases (PubMed, EMBASE, CINAHL Plus, and SCOPUS) utilizing search terms related to routine MRI and AIS, yielding 206 articles. Studies included had at least 20 participants, patients with ages 11 to 21 years, and a Methodological Index for Non-Randomized Studies (MINORS) study quality score of 8 and 16 points for noncomparative and comparative studies, respectively. Non-English manuscripts, animal studies, and those that did not include patients with AIS solely were excluded. Eighteen articles with 4746 patients were included for analysis of the overall proportion of neuraxial abnormalities, 12 articles with 3028 patients for analysis by sex, eight articles with 1603 patients for right main thoracic curve, eight articles with 665 patients for a left main thoracic curve, and 13 articles with 3063 patients and 230 (7.5%) abnormalities for number of neurosurgical interventions before scoliosis correction. The mean MINORS score for studies included was 14 (range, 10-20). Each study was analyzed for the proportion of patients identified with neuraxial abnormalities and associations with specific demographics. We determined the proportion of patients who underwent surgical interventions before scoliosis surgery as well as the types of neuraxial lesions identified. The articles were assessed for heterogeneity and publication bias. Because all groups were determined to be heterogeneous, a random-effects model was used for each group in this meta-analysis; with this analysis, an overlap of 95% confidence intervals suggests no difference at the p < 0.05 level, but this analytic approach does not provide p values. Results The pooled proportion of neuraxial abnormalities detected on MRI was 8% (95% confidence interval [CI], 6%-12%). With the numbers available, we found no difference in the proportion of male and female patients with neuraxial abnormalities (18% [95% CI, 11%-29%] versus 9% [95% CI, 6%-12%], respectively). Likewise, there was no difference in the proportion of pooled neuraxial abnormalities in right and left curves (9% [95% CI, 6%-14%] versus 15% [95% CI, 5%-35%], respectively). In the subset of abnormalities analyzed for number of neurosurgical interventions before scoliosis correction, the pooled proportion showed that 33% (95% CI, 24%-43%) underwent neurosurgical intervention before deformity correction. The most common abnormalities of the 367 found on MRI were syringomyelia in 127 patients (35%), Arnold-Chiari Type 1 malformation with syrinx in 103 patients (28%), and isolated Arnold-Chiari Type 1 malformation in 91 patients (25%). Conclusions The proportion of patients with AIS who have neuraxial abnormalities is high (8%) and a large number undergo surgical intervention before scoliosis reconstruction. We did not find any particular demographic variables that indicated an increased risk of abnormality. Clinicians should consider advanced imaging before surgical intervention in the treatment of a patient with an idiopathic diagnosis. Preventable variables need to be identified by future studies to establish a better working treatment protocol for these patients. Level of Evidence Level III, diagnostic study.

Clinical Differences Between Monomicrobial and Polymicrobial Vertebral Osteomyelitis

Little literature exists examining differences in presentation and outcomes between monomicrobial and polymicrobial vertebral infections. Seventy-nine patients treated for vertebral osteomyelitis between 2001 and 2011 were reviewed. Patients were divided into monomicrobial and polymicrobial cohorts based on type of infection. Various characteristics were compared between the 2 groups. The 26 patients with a polymicrobial infection were older and had a higher mortality rate, lower clearance of infection, larger infection, more vertebral instability, higher erythrocyte sedimentation rate at presentation, and longer mean length of stay. There were no significant differences in Oswestry Disability Index scores at final follow-up, but there were differences in presentation and clinical outcomes between monomicrobial and polymicrobial vertebral osteomyelitis. Patients may benefit from counseling regarding their disease type and potential prognosis. [Orthopedics. 2017; 40(2):e370-e373.].

Low energy chronic traumatic spondylolisthesis of the axis

ObjectiveThe aim of this study is to present a unique case of a patient who presented to our Emergency Department with evidence of a chronic traumatic spondylolisthesis of the axis with severe displacement treated with anterior cervical discectomy and fusion (ACDF) of C2–C3 as well as and posterior cervical fusion (PCF) of C1–C3.MethodsOne patient with an untreated traumatic spondylolisthesis of the axis with Levine type II injury pattern and 1.2 cm of anterior subluxation underwent ACDF C2–C3 and PCF C1–C3.ResultsThe patient recovered well, radiographs demonstrated reduction of the anterior subluxation, and the patient reported a neck disability index (NDI) score of 20 at 6-month follow-up with full neurologic function intact. The patient was then lost to follow-up.ConclusionIn this report, we present an alcoholic patient with a history of many falls who presented with a Levine type II traumatic spondylolisthesis of the axis with signs of chronicity seen on magnetic resonance imaging (MRI). We were able to partially reduce the anterior displacement with traction, but needed both anterior and posterior cervical approaches to achieve adequate reduction and stabilization of the injury.

Outcomes of Instrumented and Noninstrumented Posterolateral Lumbar Fusion

The purpose of this study was to evaluate the long-term clinical and radiographic outcomes of posterolateral lumbar fusion for lumbar stenosis cases requiring bilateral facetectomy in conjunction with a laminectomy. The authors evaluated 34 consecutive patients who had undergone a lumbar laminectomy, bilateral partial facetectomy, and posterolateral fusion at a single institution between 1981 and 1996. They included 25 men and 9 women with a mean age of 42 years (range, 27-57 years). Twenty-three cases were instrumented and 11 were noninstrumented. Mean follow-up was 21 years (range, 15-29 years). Outcomes evaluated included reoperation rate, clinical outcomes evaluated by the Oswestry Disability Index (ODI) score, radiographic evaluations of adjacent segmental degeneration (ASD) and lumbar lordosis, and contributing demographic factors to disease progression. At final follow-up, 17 of the 34 patients had undergone reoperation (43% of the instrumented group and 64% of the noninstrumented group). There were no differences in the reoperation rate or ODI improvement between the instrumented and noninstrumented groups (P>.05). Female patients required more revisions, had less ODI improvement, had greater postoperative ASD, and had less maintenance of their postoperative lumbar lordosis. There was no difference in maintenance of postoperative lumbar lordosis or ASD between the instrumented and noninstrumented groups. Instrumentation did not improve revision rates, clinical outcomes, or radiographic outcomes in laminectomies requiring contemporaneous facetectomies.

Hip Flexion Contracture Caused by an Intraspinal Osteochondroma of the Lumbar Spine

Osteochondroma (or osteocartilaginous exostosis) is the most common bone tumor of childhood, with an incidence ranging from 1 to 1.4 per 1,000,000. In the lumbar spine, osteochondromata usually arise from the posterior column at the secondary ossification center and grow away from the spinal canal without causing neurologic deficits. This article reports a rare intraspinal lumbar osteochondroma that compressed the thecal sac, resulting in a hip flexion contracture in an 11-year-old boy. This lumbar, intraspinal, extradural exostosis was confluent with the L3 inferior articular process and compressed the L3 nerve root and thecal sac severely. The patient underwent an en bloc resection of the tumor with a right-sided hemilaminectomy of L3 and L4, a right-sided partial facetectomy at L3 to L4, and an extended resection from the pars intra-articularis of the L2 to the L5 vertebrae. The tumor specimen measured 4.8×3.7×2.5 cm with clear margins. Instrumented posterolateral fusion was completed from L2 to L5 due to iatrogenic instability from the resection. The patient had an uneventful recovery and returned to his normal activities of daily living, including sports. He remains asymptomatic at 54-month follow-up. A solitary lumbar osteochondroma that compresses the spinal cord, resulting in a motor neurological deficit, has not been reported in a pediatric patient. Orthopedic surgeons should be aware of potential intraspinal presentation of osteochondromas. Magnetic resonance imaging is the modality of choice in diagnosing and screening for spinal osteochondromas. These cases can be treated with resection surgery.