Cervical kyphosis after posterior cervical laminectomy with and without fusion.

BACKGROUND: Cervical posterior instrumentation and fusion is often performed to avoid post-laminectomy kyphosis. However, larger comparative analyses of cervical laminectomy with or without fusion are sparse. METHODS: A retrospective, two-center, comparative cohort study included patients after stand-alone dorsal laminectomy with (n = 91) or without (n = 46) additional fusion for degenerative cervical myelopathy with a median follow-up of 59 (interquartile range (IQR) 52) months. The primary outcome was the C2-7 Cobb angle and secondary outcomes were Neck Disability Index (NDI), modified Japanese Orthopaedic Association (mJOA) scale, revision rates, T1 slope and C2-7 sagittal vertical axis (C2-7 SVA) at final follow-up. Logistic regression analysis adjusted for potential confounders (i.e. age, operated levels, and follow-up). RESULTS: Preoperative C2-7 Cobb angle and T1 slope were higher in the laminectomy group, while the C2-7 SVA was similar. The decrease in C2-7 Cobb angle from pre- to postoperatively was more pronounced in the laminectomy group (- 6° (IQR 20) versus -1° (IQR 7), p = 0.002). When adjusting for confounders, the decrease in C2-7 Cobb angle remained higher in the laminectomy group (coefficient - 12 (95% confidence interval (CI) -18 to -5), p = 0.001). However, there were no adjusted differences for postoperative NDI (- 11 (- 23 to 2), p = 0.10), mJOA, revision rates, T1 slope and C2-7 SVA. CONCLUSION: Posterior cervical laminectomy without fusion is associated with mild loss of cervical lordosis of around 6° in the mid-term after approximately five years, however without any clinical relevance regarding NDI or mJOA in well-selected patients (particularly in shorter segment laminectomies of < 3 levels).

Effect of reversal of residual neuromuscular blockade on the amplitude of motor evoked potentials: a randomized controlled crossover study comparing sugammadex and placebo.

PURPOSE: To compare the amplitude changes in motor evoked potentials (MEP) with reversal of residual neuromuscular blockade using sugammadex or placebo in patients with cervical myelopathy. METHODS: In this prospective randomized double-blind, placebo-controlled crossover trial, 38 patients with cervical myelopathy undergoing posterior cervical decompression and fusion were randomized to either sugammadex (2mg/kg) or placebo. The primary outcome measure was the increase in amplitude of the MEP in the first dorsal interossei (FDI) muscle at 3 min. Mann-Whitney U test was used to analyze the primary outcome measure. RESULTS: There was a significant increase in the amplitude of MEP at 3 min with sugammadex when compared to placebo group. The median (IQR) increase in MEP amplitude (µV) at 3 min from the left FDI in sugammadex and placebo group was 652.9 (142:1650) and 20.6 (-183.5:297.5) (p <0.001), respectively. Corresponding values from right FDI were 2153.4 (1400:4536.8) and 55(-65.2:480.8) (p=<0.001). CONCLUSION: Our study showed that there was a 200% increase in the MEP amplitude in the first dorsal interosseous muscle at 3 min following reversal of residual neuromuscular blockade with sugammadex. By ensuring that maximal MEP amplitude is recorded at baseline, early commencement of neuromonitoring can be achieved. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION: The study was registered at http://clinicaltrials.gov , ID NCT03087513, Feb 5th 2018.

Emergent and Urgent Transfers to Neurosurgical Centers in Ontario.

Critically ill neurosurgical patients require expedient access to neurosurgical centers (NC) to improve outcome. In regionalized health systems patients are often initially evaluated at a non-neurosurgical center (NNC) and are subsequently transferred to a NC using air or ground vehicles. We sought to identify barriers to accessing a NC for critically ill patients by analyzing interfacility transfer times and referral patterns in the province of Ontario. A retrospective observational analysis was undertaken. The cohort included patients in Ontario with emergent and urgent neurologic pathologies who underwent transfer from a NNC to NC between January 1, 2011 and December 31, 2013. Timing, clinical, and geographic data were collected for each transfer. We identified 1103 emergent/urgent transfers. The median transfer time to a NC was 3.4 h (IQR -2.2, 3.8) and varied by the geographic region of origin. A total of 17% of the patients bypassed a closer NC during transfer to their destination NC. Transfers that bypassed a closer NC travelled further (101 miles vs. 296 miles, p < 0.001), took longer (3.1 h vs. 3.9 h, p < 0.001), and in some regions were associated with a higher risk of in-transit clinical decline (3.0% vs. 8.3%, p < 0.05) when compared with transfers that ended at the closest NC. Regionalization of neurosurgical services in Ontario has led to heavy reliance upon patient transfers to maintain continuity of care. Access to a NC varied across the province, which may represent regional differences in neurosurgical bed availability, resource limitations at smaller NCs, or environmental factors. Our descriptions of referral patterns and transport times can guide health system planning in Ontario and similar jurisdictions in the United States and Canada.

Clinical and pathological outcomes after resection of intramedullary spinal cord tumors: a single-institution case series.

OBJECTIVE The objective of this study was to identify clinically relevant predictors of progression-free survival and functional outcomes in patients who underwent surgery for intramedullary spinal cord tumors (ISCTs). METHODS An institutional spinal tumor registry and billing records were reviewed to identify adult patients who underwent resection of ISCTs between 1993 and 2014. Extensive data were collected from patient charts and operative notes, including demographic information, extent of resection, tumor pathology, and functional and oncological outcomes. Survival analysis was used to determine important predictors of progression-free survival. Logistic regression analysis was used to evaluate the association between an "optimal" functional outcome on the Frankel or McCormick scale at 1-year follow-up and various clinical and surgical characteristics. RESULTS The consecutive case series consisted of 63 patients (50.79% female) who underwent resection of ISCTs. The mean age of patients was 41.92 ± 14.36 years (range 17.60-75.40 years). Complete microsurgical resection, defined as no evidence of tumor on initial postoperative imaging, was achieved in 34 cases (54.84%) of the 62 patients for whom this information was available. On univariate analysis, the most significant predictor of progression-free survival was tumor histology (p = 0.0027). Patients with Grade I/II astrocytomas were more likely to have tumor progression than patients with WHO Grade II ependymomas (HR 8.03, 95% CI 2.07-31.11, p = 0.0026) and myxopapillary ependymomas (HR 8.01, 95% CI 1.44-44.34, p = 0.017). Furthermore, patients who underwent radical or subtotal resection were more likely to have tumor progression than those who underwent complete resection (HR 3.46, 95% CI 1.23-9.73, p = 0.018). Multivariate analysis revealed that tumor pathology was the only significant predictor of tumor progression. On univariate analysis, the most significant predictors of an "optimal" outcome on the Frankel scale were age (OR 0.94, 95% CI 0.89-0.98, p = 0.0062), preoperative Frankel grade (OR 4.84, 95% CI 1.33-17.63, p = 0.017), McCormick score (OR 0.22, 95% CI 0.084-0.57, p = 0.0018), and region of spinal cord (cervical vs conus: OR 0.067, 95% CI 0.012-0.38, p = 0.0023; and thoracic vs conus: OR 0.015: 95% CI 0.001-0.20, p = 0.0013). Age, tumor pathology, and region were also important predictors of 1-year McCormick scores. CONCLUSIONS Extent of tumor resection and histopathology are significant predictors of progression-free survival following resection of ISCTs. Important predictors of functional outcomes include tumor histology, region of spinal cord in which the tumor is present, age, and preoperative functional status.

Riluzole for Degenerative Cervical Myelopathy: A Secondary Analysis of the CSM-PROTECT Trial.

Importance: The modified Japanese Orthopaedic Association (mJOA) scale is the most common scale used to represent outcomes of degenerative cervical myelopathy (DCM); however, it lacks consideration for neck pain scores and neglects the multidimensional aspect of recovery after surgery. Objective: To use a global statistical approach that incorporates assessments of multiple outcomes to reassess the efficacy of riluzole in patients undergoing spinal surgery for DCM. Design, Setting, and Participants: This was a secondary analysis of prespecified secondary end points within the Efficacy of Riluzole in Surgical Treatment for Cervical Spondylotic Myelopathy (CSM-PROTECT) trial, a multicenter, double-blind, phase 3 randomized clinical trial conducted from January 2012 to May 2017. Adult surgical patients with DCM with moderate to severe myelopathy (mJOA scale score of 8-14) were randomized to receive either riluzole or placebo. The present study was conducted from July to December 2023. Intervention: Riluzole (50 mg twice daily) or placebo for a total of 6 weeks, including 2 weeks prior to surgery and 4 weeks following surgery. Main Outcomes and Measures: The primary outcome measure was a difference in clinical improvement from baseline to 1-year follow-up, assessed using a global statistical test (GST). The 36-Item Short Form Health Survey Physical Component Score (SF-36 PCS), arm and neck pain numeric rating scale (NRS) scores, American Spinal Injury Association (ASIA) motor score, and Nurick grade were combined into a single summary statistic known as the global treatment effect (GTE). Results: Overall, 290 patients (riluzole group, 141; placebo group, 149; mean [SD] age, 59 [10.1] years; 161 [56%] male) were included. Riluzole showed a significantly higher probability of global improvement compared with placebo at 1-year follow-up (GTE, 0.08; 95% CI, 0.00-0.16; P = .02). A similar favorable global response was seen at 35 days and 6 months (GTE for both, 0.07; 95% CI, -0.01 to 0.15; P = .04), although the results were not statistically significant. Riluzole-treated patients had at least a 54% likelihood of achieving better outcomes at 1 year compared with the placebo group. The ASIA motor score and neck and arm pain NRS combination at 1 year provided the best-fit parsimonious model for detecting a benefit of riluzole (GTE, 0.11; 95% CI, 0.02-0.16; P = .007). Conclusions and Relevance: In this secondary analysis of the CSM-PROTECT trial using a global outcome technique, riluzole was associated with improved clinical outcomes in patients with DCM. The GST offered probability-based results capable of representing diverse outcome scales and should be considered in future studies assessing spine surgery outcomes.

Postoperative C5 Palsy after Anterior or Posterior Decompression for Degenerative Cervical Myelopathy: A Subgroup Analysis of the Multicenter, Prospective, Randomized, Phase III, CSM-Protect Clinical Trial.

STUDY DESIGN: Retrospective cohort study of prospectively accrued data. OBJECTIVE: To evaluate a large, prospective, multicentre dataset of surgically-treated DCM cases on the contemporary risk of C5 palsy with surgical approach. SUMMARY OF BACKGROUND DATA: The influence of surgical technique on postoperative C5 palsy after decompression for degenerative cervical myelopathy (DCM) is intensely debated. Comprehensive analyses are needed using contemporary data and accounting for covariates. METHODS: Patients with moderate to severe DCM were prospectively enrolled in the multicenter, randomized CSM-Protect clinical trial and underwent either anterior or posterior decompression between Jan 31, 2012, to May 16, 2017. The primary outcome was the incidence of postoperative C5 palsy, defined as onset of muscle weakness by at least one grade in manual muscle test at the C5 myotome with slight or absent sensory disruption after cervical surgery. Two comparative cohorts were made based on anterior or posterior surgical approach. Multivariate hierarchical mixed-effects logistic regression was used to estimate odds ratios (OR) with 95% confidence intervals (CI) for C5 palsy. RESULTS: A total of 283 patients were included, and 53.4% underwent posterior decompression. The total incidence of postoperative C5 palsy was 7.4% and was significantly higher in patients that underwent posterior decompression compared to anterior decompression (11.26% vs. 3.03%, P=0.008). After multivariable regression, posterior approach was independently associated with greater than four times the likelihood of postoperative C5 palsy (P=0.017). Rates of C5 palsy recovery were comparable between the two surgical approaches. CONCLUSION: The odds of postoperative C5 palsy are significantly higher after posterior decompression compared to anterior decompression for DCM. This may influence surgical decision-making when there is equipoise in deciding between anterior and posterior treatment options for DCM. LEVEL OF EVIDENCE: Therapeutic Level II.

Spontaneous intracranial hypotension due to CSF-venous fistula: Evaluation of renal accumulation of contrast following decubitus myelography and maintained decubitus CT to improve fistula localization.

PURPOSE: Presented here is a strategy of sequential lateral decubitus digital subtraction myelography (LDDSM) followed closely by lateral decubitus CT (LDCT) to facilitate cerebrospinal fluid (CSF)-venous fistula (CVF) localization. MATERIALS AND METHODS: This is a retrospective analysis of patients referred to our institution for evaluation of CSF leak. Patients with Type 1 and Type 2 leaks, and those not displaying MR brain stigmata of intracranial hypotension were excluded. All patients underwent consecutive LDDSM and LDCT. If the CVF was not localized on the first LDDSM-LDCT pair the patient returned for contralateral examinations. Images were reviewed for CVF and for accumulation of contrast within the renal pelvises expressed as a renal pelvis contrast score (RPCS) in Hounsfield units (HU). RESULTS: Twenty-two patients were included in this study. In 21 of 22 patients (95%) a CVF was identified yielding an RPCS for the LDDSM-LDCT pair ipsilateral to the CVF ranging from 71 to 423 with an average of 146 HU. An RPCS of the negative side LDDSM-LDCT pair contralateral to a CVF was available in 8 patients and averaged 51 HU. In 4 patients the initial bilateral LDDSM-LDCT pairs did not reveal the location of the CVF however in 3 of these 4 cases the CVF was revealed on a third LDDSM repeated ipsilateral to the higher RPCS. CONCLUSION: The strategy of sequential LDDSM-LDCT coupled with evaluation of renal accumulation of contrast agent appears to improve the rate of CVF localization and warrants further evaluation.

Clinical outcomes and revision rates following four-level anterior cervical discectomy and fusion.

Studies on outcomes after four-level anterior cervical discectomy and fusion (ACDF) are limited in the literature. The purpose of this study was to report on clinical outcomes and revision rates following four-level ACDF. Patients operated with four-level ACDF were identified in a prospectively accrued single institution database. Outcome scores included the Neck Disability Index (NDI) and Visual Analogue Scale (VAS) for neck and arm pain. Reoperation rates were determined. Any complications were identified from a review of the medical records. Twenty-eight patients with a minimum of 12 months follow up were included in the analysis. The mean age at surgery was 58.5 years. The median radiographic follow up time was 23 (IQR = 16-31.25) months. Cervical lordosis was significantly improved postoperatively (- 1 to - 13, p < 0.001). At the median 24 (IQR = 17.75-39.50) months clinical follow up time, there was a significant improvement in the NDI (38 to 28, p = 0.046) and VAS for neck pain scores (5.1 to 3, p = 0.012). The most common perioperative complication was transient dysphagia (32%) followed by hoarseness (14%). Four (14%) patients required revision surgery at a median 11.5 (IQR = 2-51) months postoperatively. The results of this study indicate that patients who undergo four-level ACDF have a significant improvement in clinical outcomes at median 24 months follow up. Stand-alone four-level ACDF is a valid option for the management of complex cervical degenerative conditions.

Preoperative Heart Rate Variability Predicts Postinduction Hypotension in Patients with Cervical Myelopathy: A Prospective Observational Study.

Background: Autonomic dysfunction, commonly seen in patients with cervical myelopathy, may lead to a decrease in blood pressure intraoperatively. Objective: The aim of our study is to determine if changes in Heart rate variability (HRV) could predict hypotension after induction of anesthesia in patients with cervical myelopathy undergoing spine surgery. Methods and Material: In this prospective observational study, 47 patients with cervical myelopathy were included. Five-minute resting ECG (5 lead) was recorded preoperatively and HRV of very low frequency (VLF), low frequency (LF), and high frequency (HF) spectra were calculated using frequency domain analysis. Incidence of hypotension (MAP <80 mmHg, lasting >5 min) and the number of interventions (40 mcg of phenylephrine or 5 mg of ephedrine) required to treat the hypotension during the period from induction to surgical incision were recorded. HRV indices were compared between the hypotension group and the stable group. Results: The incidence of hypotension after induction was 74.4% (35/47) and the median (IQR) interventions needed to treat hypotension was 2 (0.5-6). Patients who experienced hypotension had lower HF power and higher LF-HF ratios. A LF/HF >2.5 indicated postinduction hypotension likely. There was a correlation between increasing LF-HF ratio and the number of interventions that needs to maintain the MAP above 80 mmHg. Conclusion: HF power was lower and LF-HF ratio was higher in patients with cervical myelopathy who developed postinduction hypotension. Hence, preoperative HRV analysis can be useful to identify patients with cervical myelopathy who are at risk of post-induction hypotension.

Recent advances and new discoveries in the pipeline of the treatment of primary spinal tumors and spinal metastases: a scoping review of registered clinical studies from 2000 to 2020.

The field of spinal oncology has substantially evolved over the past decades. This review synthesizes and appraises what was learned and what will potentially be discovered from the recently completed and ongoing clinical studies related to the treatment of primary and secondary spinal neoplasms. This scoping review included all clinical studies on the treatment of spinal neoplasms registered in the ClinicalTrials.gov website from February 2000 to December 2020. The terms "spinal cord tumor," "spinal metastasis," and "metastatic spinal cord compression" were used. Of the 174 registered clinical studies on primary spinal tumors and spinal metastasis, most of the clinical studies registered in this American registry were interventional studies led by single institutions in North America (n = 101), Europe (n = 43), Asia (n = 24), or other continents (n = 6). The registered clinical studies mainly focused on treatment strategies for spinal neoplasms (90.2%) that included investigating stereotactic radiosurgery (n = 33), radiotherapy (n = 21), chemotherapy (n = 20), and surgical technique (n = 11). Of the 69 completed studies, the results from 44 studies were published in the literature. In conclusion, this review highlights the key features of the 174 clinical studies on spinal neoplasms that were registered from 2000 to 2020. Clinical trials were heavily skewed toward the metastatic population as opposed to the primary tumors which likely reflects the rarity of the latter condition and associated challenges in undertaking prospective clinical studies in this population. This review serves to emphasize the need for a focused approach to enhancing translational research in spinal neoplasms with a particular emphasis on primary tumors.

Minimally invasive surgery for spinal cerebrospinal fluid-venous fistula ligation: patient series.

BACKGROUND: Cerebrospinal fluid-venous fistulas (CVFs) may cause cerebrospinal fluid leaks resulting in spontaneous intracranial hypotension (SIH). Surgical treatment of CVFs aims to eliminate abnormal fistulous connections between the subarachnoid space and the epidural venous plexus at the level of the nerve root sleeve. The authors propose a percutaneous minimally invasive technique for surgical ligation of CVF as an alternative to the traditional open approach using a tubular retractor system. OBSERVATIONS: Minimally invasive surgical (MIS) ligation of spinal CVF was performed in 5 patients for 6 CVFs. The definite disconnection of the CVF was achieved in all patients by clipping and additional silk tie ligation of the fistula. None of the patients experienced surgical complications or required transition to an open procedure. One patient underwent 2 MIS procedures for 2 separate CVFs. Postoperative clinical follow-up and cranial magnetic resonance imaging confirmed resolution of symptoms and radiographic SIH stigmata. LESSONS: MIS ligation of CVFs is safe and efficient. It represents an elegant and less invasive procedure, reducing the risk of wound infections and time to recovery. However, preparedness for open ligation is warranted within the same surgical setting in cases of complications and difficult accessibility.

Spinal arachnoid cysts: A case series & systematic review of the literature.

Introduction: Spinal arachnoid cysts (SACs) are rare lesions with challenging and controversial management. Research question: We analyzed our experiences from a case series and provide a systematic review to determine 1) Demographic and clinical features of SACs, 2) Optimal imaging for diagnosis and operative planning, 3) Optimal management of SACs, and 4) Clinical outcomes following surgery. Materials and methods: A single-institution, ambispective analysis of patients with symptomatic SACs surgically managed between May 2005 and May 2019 was performed. Data were collected as per local ethics committee stipulations. A systematic review of SACs in adults was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and a preapproved protocol. Results: Our series consisted of 11 patients, M:F 8:3, mean age 47.8 years (range 18-73 years). Mean follow-up was 19 months (range 5-36 months). SACs were excised or marsupialised (7), fenestrated (3) or partially excised (1). Eight patients had expansile duroplasty, 3 primary dural closure. One patient had a cystoperitoneal shunt. All patients were AIS D preoperatively; 4 remained unchanged and 7 improved to AIS E at follow-up. Our systematic search retrieved 725 citations. Fourteen case series met the inclusion criteria. There was no evidence to support superiority of one surgical strategy over another. Surgery for symptomatic patients resulted in positive clinical outcomes. Discussion and conclusions: Symptomatic SACs require surgical intervention. Limited evidence suggests that decompressing the cord, breakdown of arachnoid adhesions, and establishing CSF flow by consideration of expansile duroplasty are important for positive outcomes.

Long-level intramedullary spinal cord astrocytoma complicated with spine scoliosis: Report of two cases.

INTRODUCTION AND IMPORTANCE: Long-level intramedullary astrocytomas complicated with spine scoliosis are rare. Surgical treatment of such tumors becomes more complicated and challenging when spinal scoliosis is present. However, studies describing the treatment of long segmental intramedullary spinal cord astrocytomas complicated with severe spine scoliosis have been rarely reported. CASE PRESENTATION: Two cases of long-level intramedullary astrocytomas complicated with severe spine scoliosis were surgically treated with one-stage operation of tumor resection and scoliosis correction in this report. Case 1: A 16-year-old boy presented to our hospital with a five-month progressive paresthesia, weakness of the left lower limb, and a long-time abnormal body appearance. MRI showed a T4-T12 intramedullary tumor combined with spinal scoliosis. Case 2: A 14-year-old boy presented at our service with a 6-year history of visible spine scoliosis and a 1-year progressive motor disability of bilateral lower limbs. Spine MRI indicated a long-level abnormal syringomyelia signal from C4 to L1 and there was irregular enhancement after intravenous contrast medium administration at C7-T2 and T9-T12 level. DISCUSSION: We performed a laminectomy over the whole length of the tumor and corrected the scoliosis with trans-pedicle screws. The patients exhibited a long-time tumor free with largely neurological function preservation. One-stage operation did not generate severe short- or long-term complications. The correction of the scoliosis prevented the progression of the spinal deformity and facilitated the recovery of normal life. CONCLUSION: This case report demonstrates that the one-stage resection of long-level intramedullary astrocytoma and correction of the complicated scoliosis might be a feasible option.

Clinical outcomes of nonoperatively managed degenerative cervical myelopathy: an ambispective longitudinal cohort study in 117 patients.

OBJECTIVE: Degenerative cervical myelopathy (DCM) is among the most common pathologies affecting the spinal cord but its natural history is poorly characterized. The purpose of this study was to investigate functional outcomes in patients with DCM who were managed nonoperatively as well as the utility of quantitative clinical measures and MRI to detect deterioration. METHODS: Patients with newly diagnosed DCM or recurrent myelopathic symptoms after previous surgery who were initially managed nonoperatively were included. Retrospective chart reviews were performed to analyze clinical outcomes and anatomical MRI scans for worsening compression or increased signal change. Quantitative neurological assessments were collected prospectively, including modified Japanese Orthopaedic Association (mJOA) score; Quick-DASH; graded redefined assessment of strength, sensation, and prehension-myelopathy version (GRASSP-M: motor, sensory, and dexterity); grip dynamometer; Berg balance scale score; gait stability ratio; and gait variability index. A deterioration of 10% was considered significant (e.g., a 2-point decrease in mJOA score). RESULTS: A total of 117 patients were included (95 newly diagnosed, 22 recurrent myelopathy), including 74 mild, 28 moderate, and 15 severe cases. Over a mean follow-up of 2.5 years, 57% (95% CI 46%-67%) of newly diagnosed patients and 73% (95% CI 50%-88%) of patients with recurrent DCM deteriorated neurologically. Deterioration was best detected with grip strength (60%), GRASSP dexterity (60%), and gait stability ratio (50%), whereas the mJOA score had low sensitivity (33%) in 50 patients. A composite score had a sensitivity of 81% and a specificity of 82%. The sensitivity of anatomical MRI was 28% (83 patients). CONCLUSIONS: DCM appears to have a poor natural history; however, prospective studies are needed for validation. Serial assessments should include mJOA score, grip strength, dexterity, balance, and gait analysis. The absence of worsening on anatomical MRI or in mJOA scores is not sufficient to determine clinical stability.

Inter-rater Reliability of the Modified Japanese Orthopedic Association Score in Degenerative Cervical Myelopathy: A Cross-sectional Study.

STUDY DESIGN: Prospective cross-sectional blinded-assessor cohort study. OBJECTIVE: The aim of this study was to determine the inter-rater reliability of the modified Japanese Orthopaedic Association (mJOA) score in a large cohort of degenerative cervical myelopathy (DCM) patients. SUMMARY OF BACKGROUND DATA: The mJOA score is widely accepted as the primary outcome measure in DCM; it has been utilized in clinical practice guidelines and directly influences treatment recommendations, but its reliability has not been established. METHODS: A refined version of the mJOA was administered to DCM patients by two or more blinded clinicians. Inter-rater reliability was measured using intraclass correlation coefficient (ICC), agreement, and mean difference for mJOA total score and subscores. Data were also analyzed with analysis of variance for differences by mJOA severity (mild: 15-17, moderate: 12-14, severe: <12), assessor, assessment order, previous surgery, age, and sex. RESULTS: One hundred fifty-four DCM patients underwent 322 mJOA assessments (183 paired assessments). ICC was 0.88 for total mJOA, 0.79 for upper extremity (UE) motor, 0.84 for lower extremity (LE) motor, 0.63 for UE sensation, and 0.78 for urinary function subscores. Paired assessments were identical across all four subscores in 25%. The mean difference in mJOA was 0.93 points between assessors, and this differed by severity (mild: 0.68, moderate: 1.24, severe: 0.87, P = 0.001). Differences of ≥ 2 points occurred in 19%. Disagreement between mild and moderate severity occurred in 12% of patients. Other variables did not demonstrate significant relationships with mJOA scores. CONCLUSION: The inter-rater reliability of total mJOA and its subscores is good, except for UE sensory function (moderate). However, the vast majority of assessments differed between observers, indicating that this measure should be interpreted carefully, particularly when near the threshold between severity categories, or when a patient is reassessed for deterioration. Further efforts to educate clinicians on administration and to refine the UE sensory subscore may enhance the reliability of this tool.Level of Evidence: 1.

Safety and efficacy of riluzole in patients undergoing decompressive surgery for degenerative cervical myelopathy (CSM-Protect): a multicentre, double-blind, placebo-controlled, randomised, phase 3 trial.

BACKGROUND: Degenerative cervical myelopathy represents the most common form of non-traumatic spinal cord injury. This trial investigated whether riluzole enhances outcomes in patients undergoing decompression surgery for degenerative cervical myelopathy. METHODS: This multicentre, double-blind, placebo-controlled, randomised, phase 3 trial was done at 16 university-affiliated centres in Canada and the USA. Patients with moderate-to-severe degenerative cervical myelopathy aged 18-80 years, who had a modified Japanese Orthopaedic Association (mJOA) score of 8-14, were eligible. Patients were randomly assigned (1:1) to receive either oral riluzole (50 mg twice a day for 14 days before surgery and then for 28 days after surgery) or placebo. Randomisation was done using permuted blocks stratified by study site. Patients, physicians, and outcome assessors remained masked to treatment group allocation. The primary endpoint was change in mJOA score from baseline to 6 months in the intention-to-treat (ITT) population, defined as all individuals who underwent randomisation and surgical decompression. Adverse events were analysed in the modified intention-to-treat (mITT) population, defined as all patients who underwent randomisation, including those who did not ultimately undergo surgical decompression. This study is registered with ClinicalTrials.gov, NCT01257828. FINDINGS: From Jan 31, 2012, to May 16, 2017, 408 patients were screened. Of those screened, 300 were eligible (mITT population); 290 patients underwent decompression surgery (ITT population) and received either riluzole (n=141) or placebo (n=149). There was no difference between the riluzole and placebo groups in the primary endpoint of change in mJOA score at 6-month follow-up: 2·45 points (95% CI 2·08 to 2·82 points) versus 2·83 points (2·47 to 3·19), difference -0·38 points (-0·90 to 0·13; p=0·14). The most common adverse events were neck or arm or shoulder pain, arm paraesthesia, dysphagia, and worsening of myelopathy. There were 43 serious adverse events in 33 (22%) of 147 patients in the riluzole group and 34 serious adverse events in 29 (19%) of 153 patients in the placebo group. The most frequent severe adverse events were osteoarthrosis of non-spinal joints, worsening of myelopathy, and wound complications. INTERPRETATION: In this trial, adjuvant treatment for 6 weeks perioperatively with riluzole did not improve functional recovery beyond decompressive surgery in patients with moderate-to-severe degenerative cervical myelopathy. Whether riluzole has other benefits in this patient population merits further study. FUNDING: AOSpine North America.

Admission and acute complication rate for outpatient lumbar microdiscectomy.

OBJECTIVE: Specialization is generally independently associated with improved outcomes for most types of surgery. This is the first study comparing the immediate success of outpatient lumbar microdiscectomy with respect to acute complication and conversion to inpatient rate. Long-term pain relief is not examined in this study. METHODS: Two separate prospective databases (one belonging to a neurosurgeon and brain tumor specialist, not specializing in spine (NS) and one belonging to four spine surgeons (SS)) were retrospectively reviewed. All acute complications as well as admission data of patients scheduled for outpatient lumbar microdiscectomy were extracted. RESULTS: In total, 269 patients were in the NS group and 137 patients were in the SS group. The NS group averaged 24 cases per year while the SS group averaged 50 cases per year. Chi-square tests revealed no difference in acute complication rate [NS (6.7%), SS (7.3%)] (p > 0.5) and admission rate [NS (4.1%), SS (5.8%)] (p = 0.4) while the SS group had a significantly higher proportion of patients undergoing repeat microdiscectomy [NS (4.1%), SS (37.2%)] (p < 0.0001). Excluding revision operations, there was no statistically significant difference in acute complication [NS (5.4%), SS (1.2%)] (p = 0.09) and conversion to inpatient [NS (4.3%), SS (4.6%)] (p > 0.5) rate. The combined acute complication and conversion to inpatient rate was 6.9% and 4.7% respectively. CONCLUSION: Based on this limited study, outpatient lumbar microdiscectomy can be apparently performed safely with similar immediate complication rates by both non-spine specialized neurosurgeons and spine surgeons, even though the trend favored the latter group for both outcome measures.

Exploring the role of 3-dimensional simulation in surgical training: feedback from a pilot study.

STUDY DESIGN: Randomized control study assessing the efficacy of a pedicle screw insertion simulator. OBJECTIVES: To evaluate the efficacy of an in-house developed 3-dimensional software simulation tool for teaching pedicle screw insertion, to gather feedback about the utility of the simulator, and to help identify the context and role such simulation has in surgical education. SUMMARY OF BACKGROUND DATA: Traditional instruction for pedicle screw insertion technique consists of didactic teaching and limited hands-on training on artificial or cadaveric models before guided supervision within the operating room. Three-dimensional computer simulation can provide a valuable tool for practicing challenging surgical procedures; however, its potential lies in its effective integration into student learning. METHODS: Surgical residents were recruited from 2 sequential years of a spine surgery course. Patient and control groups both received standard training on pedicle screw insertion. The patient group received an additional 1-hour session of training on the simulator using a CT-based 3-dimensional model of their assigned cadaver's spine. Qualitative feedback about the simulator was gathered from the trainees, fellows, and staff surgeons, and all pedicles screws physically inserted into the cadavers during the courses were evaluated through CT. RESULTS: A total of 185 thoracic and lumbar pedicle screws were inserted by 37 trainees. Eighty-two percent of the 28 trainees who responded to the questionnaire and all fellows and staff surgeons felt the simulator to be a beneficial educational tool. However, the 1-hour training session did not yield improved performance in screw placement. CONCLUSIONS: A 3-dimensional computer-based simulation for pedicle screw insertion was integrated into a cadaveric spine surgery instructional course. Overall, the tool was positively regarded by the trainees, fellows, and staff surgeons. However, the limited training with the simulator did not translate into widespread comfort with its operation or into improvement in physical screw placement.

The Treatment of Perioperative Spinal Cord Injury With Hyperbaric Oxygen Therapy: A Case Report.

STUDY DESIGN: Case report (level IV evidence). OBJECTIVE: To describe a potential novel application of hyperbaric oxygen therapy (HBOT) in the successful treatment of a postoperative spinal cord injury. SUMMARY OF BACKGROUND DATA: A 68-year-old man presented with an acute spinal cord injury (ASIA impairment scale D), on the background of degenerative lower thoracic and lumbar canal stenosis. He underwent emergent decompression and instrumented fusion (T9-L5), with an uncomplicated intraoperative course and no electrophysiological changes. Immediate postoperative assessment demonstrated profound bilateral limb weakness (1/5 on the Medical Research Council [MRC] grading scale, ASIA impairment scale B), without radiological abnormality. METHODS: Conventional medical management (hypertension, level 2 care) was instigated with the addition of Riluzole, with no effect after 30 hours. At 36 hours 100% oxygen at 2.8 atmospheres was applied for 90 minutes, and repeated after 8 hours, with a further three treatments over 48 hours. RESULTS: The patient demonstrated near-immediate improvement in lower limb function to anti-gravity (MRC grading 3/5) after one treatment. Motor improvement continued over the following treatments, and after 2 weeks the patient was ambulatory. At 4 months, the patient demonstrated normal motor function with no sphincteric disturbance. CONCLUSION: The application of HBOT contributed to the immediate and sustained improvement (ASIA B to ASIA E) in motor recovery after postoperative spinal cord injury. HBOT may represent a new avenue of therapy for spinal cord injury, and requires further prospective investigation. LEVEL OF EVIDENCE: 4.

Quantitative Assessment of Gait Characteristics in Degenerative Cervical Myelopathy: A Prospective Clinical Study.

It is challenging to discriminate the early presentation of Degenerative Cervical Myelopathy (DCM) as well as sensitively and accurately distinguishing between mild, moderate, and severe levels of impairment. As gait dysfunction is one of the cardinal symptoms of DCM, we hypothesized that spatiotemporal gait parameters, including the enhanced gait variability index (eGVI), could be used to sensitively discriminate between different severities of DCM. A total of 153 patients recently diagnosed with DCM were recruited and stratified on the basis of DCM severity grades, as measured using the modified Japanese Orthopedic Association (mJOA) scale. Demographic information and neurological status were collected. Gait assessments were performed using an 8 m walkway. Spearman rank correlation was used to identify relationships between gait parameters and mJOA values as well as the mJOA lower extremity (LE) subscore. Kruskal-Wallis H test was performed to evaluate differences between severity groups, as defined by mJOA classification. A significant and relatively strong correlation was found between the mJOA score and eGVI, as well as between the LE subscore of the mJOA and eGVI. Significant differences in the eGVI (X2(2, N = 153) = 55.04, p < 0.0001, ε2 = 0.36) were found between all groups of DCM severity, with a significant increase in the eGVI as DCM progressed from mild to moderate. The eGVI was the most discriminative gait parameter, which facilitated objective differentiation between varying severities of DCM. Quantitative gait assessments show promise as an accurate and objective tool to diagnose and classify DCM, as well as to potentially evaluate the impact of therapeutic interventions.