Pre-operative expectations of patients with degenerative cervical myelopathy: an observational study from the Canadian Spine Outcomes and Research Network.

BACKGROUND: Despite an abundance of literature on degenerative cervical myelopathy (DCM), little is known about pre-operative expectations of these patients. PURPOSE: The primary objective was to describe patient pre-operative expectations. Secondary objectives included identifying patient characteristics associated with high pre-operative expectations and to determine if expectations varied depending on myelopathy severity. STUDY DESIGN: This was a retrospective study of a prospective multicenter, observational cohort of patients with DCM. PATIENT SAMPLE: Patients who consented to undergo surgical treatment between January 2019 and September 2022 were included. OUTCOMES MEASURES: An 11-domain expectation questionnaire was completed pre-operatively whereby patients quantified the expected change in each domain. METHODS: The most important expected change was captured. A standardized expectation score was calculated as the sum of each expectation divided by the maximal possible score. The high expectation group was defined by patients who had an expectation score above the 75th percentile. Predictors of patients with high expectations were determined using multivariable logistic regression models. RESULTS: There were 262 patients included. The most important patient expectation was preventing neurological worsening (40.8%) followed by improving balance when standing or walking (14.5%), improving independence in everyday activities (10.3%), and relieving arm tingling, burning and numbness (10%). Patients with mild myelopathy were more likely to select no worsening as the most important expected change compared to patients with severe myelopathy (p<.01). Predictors of high patient expectations were: having fewer comorbidities (OR -0.30 for every added comorbidity, 95% CI -0.59 to -0.10, p=.01), a shorter duration of symptoms (OR 0.92, 95% CI 0.35-1.19, p=.02), no contribution from "failure of other treatments" on the decision to undergo surgery (OR 1.49, 95% CI 0.56-2.71, p=.02) and more severe neck pain (OR 0.19 for 1 point increase, 95% CI 0.05-0.37, p=.01). CONCLUSIONS: Most patients undergoing surgery for DCM expect prevention of neurological decline, better functional status, and improvement in their myelopathic symptoms. Stopping neurological deterioration is the most important expected outcomes by patients.

The Effects of Peri-Operative Adverse Events on Clinical and Patient-Reported Outcomes After Surgery for Degenerative Cervical Myelopathy: An Observational Cohort Study from the Canadian Spine Outcomes and Research Network.

BACKGROUND AND OBJECTIVES: There is a lack of data examining the effects of perioperative adverse events (AEs) on long-term outcomes for patients undergoing surgery for degenerative cervical myelopathy. We aimed to investigate associations between the occurrence of perioperative AEs and coprimary outcomes: (1) modified Japanese Orthopaedic Association (mJOA) score and (2) Neck Disability Index (NDI) score. METHODS: We analyzed data from 800 patients prospectively enrolled in the Canadian Spine Outcomes and Research Network multicenter observational study. The Spine AEs Severity system was used to collect intraoperative and postoperative AEs. Patients were assessed at up to 2 years after surgery using the NDI and the mJOA scale. We used a linear mixed-effect regression to assess the influence of AEs on longitudinal outcome measures as well as multivariable logistic regression to assess factors associated with meeting minimal clinically important difference (MCID) thresholds at 1 year. RESULTS: There were 167 (20.9%) patients with minor AEs and 36 (4.5%) patients with major AEs. The occurrence of major AEs was associated with an average increase in NDI of 6.8 points (95% CI: 1.1-12.4, P = .019) and reduction of 1.5 points for mJOA scores (95% CI: -2.3 to -0.8, P < .001) up to 2 years after surgery. Occurrence of major AEs reduced the odds of patients achieving MCID targets at 1 year after surgery for mJOA (odds ratio 0.23, 95% CI: 0.086-0.53, P = .001) and for NDI (odds ratio 0.34, 95% CI: 0.11-0.84, P = .032). CONCLUSION: Major AEs were associated with reduced functional gains and worse recovery trajectories for patients undergoing surgery for degenerative cervical myelopathy. Occurrence of major AEs reduced the probability of achieving mJOA and NDI MCID thresholds at 1 year. Both minor and major AEs significantly increased health resource utilization by reducing the proportion of discharges home and increasing length of stay.

Anterior vs Posterior Surgery for Patients With Degenerative Cervical Myelopathy: An Observational Study From the Canadian Spine Outcomes and Research Network.

BACKGROUND AND OBJECTIVES: The advantages and disadvantages of anterior vs posterior surgical approaches for patients with progressive degenerative cervical myelopathy (DCM) remain uncertain. Our primary objective was to evaluate patient-reported disability at 1 year after surgery. Our secondary objectives were to evaluate differences in patient profiles selected for each approach in routine clinical practice and to compare neurological function, neck and arm pain, health-related quality of life, adverse events, and rates of reoperations. METHODS: We analyzed data from patients with DCM who were enrolled in an ongoing multicenter prospective observational cohort study. We controlled for differences in baseline characteristics and numbers of spinal levels treated using multivariable logistic regression. Adverse events were collected according to the Spinal Adverse Events Severity protocol. RESULTS: Among 559 patients, 261 (47%) underwent anterior surgery while 298 (53%) underwent posterior surgery. Patients treated posteriorly had significantly worse DCM severity and a greater number of vertebral levels involved. After adjusting for confounders, there was no significant difference between approaches for odds of achieving the minimum clinically important difference for the Neck Disability Index (odds ratio 1.23, 95% CI 0.82 to 1.86, P = .31). There was also no significant difference for change in modified Japanese Orthopedic Association scores, and differences in neck and arm pain and health-related quality of life did not exceed minimum clinically important differences. Patients treated anteriorly experienced greater rates of dysphagia, whereas patients treated posteriorly experienced greater rates of wound complications, neurological complications, and reoperations. CONCLUSION: Patients selected for posterior surgery had worse DCM and a greater number of vertebral levels involved. Despite this, anterior and posterior surgeries were associated with similar improvements in disability, neurological function, pain, and quality of life. Anterior surgery had a more favorable profile of adverse events, which suggests it might be a preferred option when feasible.

Does Ending a Posterior Construct Proximally at C2 Versus C3 Impact Patient Reported Outcomes in Degenerative Cervical Myelopathy Patients up to 24 months After the Surgery?

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The primary objective was to evaluate the impact of the upper instrumented level (UIV) being at C2 vs C3 in posterior cervical construct on patient reported outcomes (PROs) up to 24 months after surgery for cervical degenerative myelopathy (DCM). Secondary objectives were to compare operative time, intra-operative blood loss (IOBL), length of stay (LOS), adverse events (AEs) and re-operation. METHODOLOGY: Patients who underwent a posterior cervical instrumented fusion (3 and + levels) with a C2 or C3 UIV, with 24 months follow-up were analyzed. PROs (NDI, EQ5D, SF-12 PCS/MCS, NRS arm/neck pain) were compared using ANCOVA. Operative duration, IOBL, AEs, and re-operation were compared. Subgroup analysis was performed on patient presenting with pre-operative malalignment (cervical sagittal vertical axis ≥40 mm and/or T1slope- cervical lordosis >15°). RESULTS: 173 patients were included, of which 41 (24%) had a C2 UIV and 132 (76%) a C3 UIV. There was no statistically significant difference between the groups for the changes in PROs up to 24 months. Subgroup analysis of patients with pre-operative malalignment showed a trend towards greater improvement in the NDI at 12 months with a C2 UIV (P = .054). Operative time, IOBL and peri-operative AEs were more in C2 group (P < .05). There was no significant difference in LOS and re-operation (P > .05). CONCLUSION: In this observational study, up to 24 months after surgery for posterior cervical fusion in DCM greater than 3 levels, PROs appear to evolve similarly.

Deterioration After Surgery for Degenerative Cervical Myelopathy: An Observational Study From the Canadian Spine Outcomes and Research Network.

STUDY DESIGN: A Prospective cohort study. OBJECTIVE: To investigate the incidence, etiology, and outcomes of patients who experience neurological deterioration after surgery for Degenerative Cervical Myelopathy (DCM). SUMMARY OF BACKGROUND DATA: Postoperative neurological deterioration is one of the most undesirable complications that can occur after surgery for DCM. METHODS: We analyzed data from the Canadian Spine Outcomes and Research Network DCM prospective cohort study. We defined postoperative neurological deterioration as any decrease in modified Japanese Orthopaedic Association (mJOA) score by at least one point from baseline to three months after surgery. Adverse events were collected using the Spinal Adverse Events Severity protocol. Secondary outcomes included patient-reported pain, disability, and health-related quality of life. RESULTS: Among a study cohort of 428 patients, 50 (12%) deteriorated by at least one mJOA point after surgery for DCM (21 by one point, 15 by two points, and 14 by three points or more). Significant risk factors included older age, female sex, and milder disease. Among those who deteriorated, 13 experienced contributing intraoperative or postoperative adverse events, six had alternative non-DCM diagnoses, and 31 did not have an identifiable reason for deterioration. Patients who deteriorated had significantly lower mJOA scores at one year after surgery [13.5 (SD 2.7) vs. 15.2 (SD 2.2), P <0.01 and those with larger deteriorations were less likely to recover their mJOA to at least their preoperative baseline, but most secondary measures of pain, disability, and health-related quality of life were unaffected. CONCLUSIONS: The incidence of deterioration of mJOA scores after surgery for DCM was approximately one in 10, but some deteriorations were unrelated to actual spinal cord impairment and most secondary outcomes were unaffected. These findings can inform patient and surgeon expectations during shared decision-making, and they demonstrate that the interpretation of mJOA scores without clinical context can sometimes be misleading.

Timing of Recovery After Surgery for Patients With Degenerative Cervical Myelopathy: An Observational Study From the Canadian Spine Outcomes and Research Network.

BACKGROUND: The time course over which postoperative neurological recovery occurs after surgery for degenerative cervical myelopathy occurs is poorly understood. OBJECTIVE: To determine the time point at which patients experience significant neurological improvement. METHODS: We reviewed data from an ongoing prospective multicenter cohort study. We measured neurological function at 3 months, 1 year, and 2 years after surgery using the modified Japanese Orthopedic Association (mJOA) scale. We implemented minimal clinical important differences (MCIDs) to guide interpretation of mJOA scores, and we used 1-way analysis of variance to compare changes between follow-up intervals. RESULTS: Among 330 patients, the mean overall mJOA improved from 12.9 (SD 2.6) to 14.6 (SD 2.4) at 3 months, 14.7 (SD 2.4) at 1 year, and 14.8 (SD 2.5) at 2 years. The difference in means was statistically significant (P < .01) at the interval from baseline to 3 months postoperatively, but not from 3 months to 1 year or 1 year to 2 years. The MCID was reached by 161 patients at 3 months, 32 more at 1 year, and 15 more at 2 years, with a statistically significant difference only at 3 months. Patients with moderate or severe disease reached the MCID more frequently than those with mild disease. CONCLUSION: Among patients who underwent surgery for degenerative cervical myelopathy, most significant neurological improvement occurred by 3 months after surgery. These findings will facilitate valid discussions about postoperative expectations during shared clinical decision making between patients and their surgeons.

Does extending a posterior cervical fusion construct into the upper thoracic spine impact patient-reported outcomes as long as 2 years after surgery in patients with degenerative cervical myelopathy?

OBJECTIVE: In multilevel posterior cervical instrumented fusion, extension of fusion across the cervicothoracic junction (CTJ) at T1 or T2 has been associated with decreased rates of reoperation and pseudarthrosis but with longer surgical time and increased blood loss. The impact on patient-reported outcomes (PROs) remains unclear. The primary objective was to determine whether extension of fusion through the CTJ influenced PROs at 3, 12, and 24 months after surgery. The secondary objective was to compare the number of patients who reached the minimal clinically important differences (MCIDs) for the PROs, modified Japanese Orthopaedic Association (mJOA) score, operative time, intraoperative blood loss, length of stay, discharge disposition, adverse events (AEs), reoperation within 24 months of surgery, and patient satisfaction. METHODS: This was a retrospective observational cohort study of prospectively collected multicenter data of patients with degenerative cervical myelopathy. Patients who underwent posterior instrumented fusion of 4 levels or greater (between C2 and T2) between January 2015 and October 2020 and received 24 months of follow-up were included. PROs (scores on the Neck Disability Index [NDI], EQ-5D, physical component summary and mental component summary of SF-12, and numeric rating scale for arm and neck pain) and mJOA scores were compared using ANCOVA and adjusted for baseline differences. Patient demographic characteristics, comorbidities, and surgical details were abstracted. The proportions of patients who reached the MCIDs for these outcomes were compared with the chi-square test. Operative duration, intraoperative blood loss, AEs, reoperation, discharge disposition, length of stay, and satisfaction was compared by using the chi-square test for categorical variables and the independent-samples t-test for continuous variables. RESULTS: A total of 198 patients were included in this study (101 patients with fusion not crossing the CTJ and 97 with fusion crossing the CTJ). Patients with a construct extending through the CTJ were more likely to be female and have worse baseline NDI scores (p > 0.05). When adjusted for baseline differences, there were no statistically significant differences between the two groups in terms of the PROs and mJOA scores at 3, 12, and 24 months. Surgical duration was longer (p < 0.001) and intraoperative blood loss was greater in the group with fusion extending to the upper thoracic spine (p = 0.013). There were no significant differences between groups in terms of AEs (p > 0.05). Fusion with a construct crossing the CTJ was associated with reoperation (p = 0.04). Satisfaction with surgery was not significantly different between groups. The proportions of patients who reached the MCIDs for the PROs were not statistically different at any time point. CONCLUSIONS: There were no statistically significant differences in PROs between patients with a posterior construct extending to the upper thoracic spine and those without such extension for as long as 24 months after surgery. The AE profiles were not significantly different, but longer surgical time and increased blood loss were associated with constructs extending across the CTJ.

Predictors of home discharge after scheduled surgery for degenerative cervical myelopathy.

OBJECTIVE: Degenerative cervical myelopathy (DCM) is an important public health issue. Surgery is the mainstay of treatment for moderate and severe DCM. Delayed discharge of patients after DCM surgery is associated with increased healthcare costs. There is a paucity of data regarding predictive factors for discharge destination after scheduled surgery for patients with DCM. The purpose of this study was to identify factors predictive of home versus nonhome discharge after DCM surgery. METHODS: Patients undergoing scheduled DCM surgery who had been enrolled in a prospective DCM substudy of the Canadian Spine Outcomes and Research Network registry between January 2015 and October 2020 were included in this retrospective analysis. Patient data were evaluated to identify potential factors predictive of home discharge after surgery. Logistic regression was used to identify independent factors predictive of home discharge. A multivariable model was then used as a final model. RESULTS: Overall, 639 patients were included in the initial analysis, 543 (85%) of whom were discharged home. The mean age of the entire cohort was 60 years (SD 11.8 years), with a BMI of 28.9 (SD 5.7). Overall, 61.7% of the patients were female. The mean length of stay was 2.72 days (SD 1.7 days). The final internally validated bootstrapped multivariable model revealed that younger age, higher 9-Item Patient Health Questionnaire score, lower Neck Disability Index scores, fewer operated levels, mJOA scores indicating mild disease, anterior cervical discectomy and fusion procedure, and no perioperative adverse effects were predictive of home discharge. CONCLUSIONS: Younger age, less neck-related disability, fewer operated levels, more significant depression, less severe myelopathy, anterior cervical discectomy and fusion procedure, and no perioperative adverse effects are predictive of home discharge after surgery for DCM. These factors can help to guide clinical decision-making and optimize postoperative care pathways.

Cervical Sagittal Alignment in Patients with Cervical Spondylotic Myelopathy: An Observational Study From the Canadian Spine Outcomes and Research Network.

STUDY DESIGN: Prospective cohort study. OBJECTIVE: Among patients with CSM, we aimed to evaluate the extent to which: (1) Preoperative cervical sagittal alignment is associated with health-related quality of life, function, and symptoms; (2) Surgery leads to changes in cervical sagittal alignment; and (3) Postoperative cervical sagittal alignment is associated with health-related quality of life, function, and symptoms at 12 months of follow-up. SUMMARY OF BACKGROUND DATA: The importance of maintaining or improving cervical sagittal alignment in the surgical management of patients with CSM has not been established. METHODS: We measured C2-C7 Cobb angle, T1 slope, and C2-C7 cervical sagittal vertical axis (cSVA). We tested for associations with Neck Disability Index, Pain Scales for neck and arm pain, EuroQol 5D, Short Form 12 Physical and Mental Component Summaries, and modified Japanese Orthopaedic Association scores. We adjusted for potential confounders using multiple linear regression, and we performed various prespecified subgroup (cSVA > 40 mm, surgical approach) and sensitivity analyses. RESULTS: Among 250 patients, adjusted analyses yielded significant inverse associations prior to surgery between each of cSVA and T1 slope with SF12 Physical Component Summaries (T1 slope: -0.14, 95% CI -0.26 to -0.01, P = 0.03; C2-C7 cSVA: -0.13, 95% CI --0.21 to -0.05 P < 0.01). Surgery was associated with a small but statistically significant increase in cSVA across the cohort (+5.8 mm [SD 11.7], P < 0.01) but no change in Cobb angle or T1 slope. At 12-months after surgery, there were no significant associations between alignment parameters or change in alignment and any measures of health-related quality of life, function, or symptoms. Results were consistent across subgroup and sensitivity analyses. CONCLUSION: Increased cSVA and T1 slope were associated with inferior health-related quality of life at presentation among patients with CSM, but no significant associations were observed following surgical treatment.Level of Evidence: 3.

Factors Associated With Return to Work After Surgery for Degenerative Cervical Spondylotic Myelopathy: Cohort Analysis From the Canadian Spine Outcomes and Research Network.

STUDY DESIGN: Retrosepctive analysis of prospectively collected data from the multicentre Canadian Surgical Spine Registry (CSORN). OBJECTIVE: Degenerative cervical myelopathy (DCM) is the most common cause of spinal cord dysfunction in North America. Few studies have evaluated return to work (RTW) rates after DCM surgery. Our goals were to determine rates and factors associated with postoperative RTW in surgically managed patients with DCM. METHODS: Data was derived from the prospective, multicenter Canadian Spine Outcomes and Research Network (CSORN). From this cohort, we included all nonretired patients with at least 1-year follow-up. The RTW rate was defined as the proportion of patients with active employment at 1 year from the time of surgery. Unadjusted and adjusted analyses were used to identify patient characteristics, disease, and treatment variables associated with RTW. RESULTS: Of 213 surgically treated DCM patients, 126 met eligibility, with 49% working and 51% not working in the immediate period before surgery; 102 had 12-month follow-up data. In both the unadjusted and the adjusted analyses working preoperatively and an anterior approach were associated with a higher postoperative RTW (P < .05), there were no significant differences between the postoperative employment groups with respect to age, gender, preoperative mJOA (modified Japanese Orthopaedic Association) score, and duration of symptoms (P > .05). Active preoperative employment (odds ratio = 15.4, 95% confidence interval = 4.5, 52.4) and anterior surgical procedures (odds ratio = 4.7, 95% confidence interval = 1.2, 19.6) were associated with greater odds of RTW at 1 year. CONCLUSIONS: The majority of nonretired patients undergoing surgery for DCM had returned to work 12 months after surgery; active preoperative employment and anterior surgical approach were associated with RTW in this analysis.

Effectiveness of Surgical Decompression in Patients With Degenerative Cervical Myelopathy: Results of the Canadian Prospective Multicenter Study.

BACKGROUND: Conflicting evidence exists regarding the effectiveness of surgery for degenerative cervical myelopathy (DCM), particularly in mild DCM. OBJECTIVE: To prospectively evaluate the impact of surgery on patient-reported outcomes in patients with mild (modified Japanese Orthopaedic Association [mJOA] ≥ 15), moderate (mJOA 12-14), and severe (mJOA < 12) DCM. METHODS: Prospective, multicenter cohort study of patients with DCM who underwent surgery between 2015 and 2019 and completed 1-yr follow-up. Outcome measures (mJOA, Neck Disability Index [NDI], EuroQol-5D [EQ-5D], Short Form [SF-12] Physical Component Score [PCS]/Mental Component Score [MCS], numeric rating scale [NRS] neck, and arm pain) were assessed at 3 and 12 mo postoperatively and compared to baseline, stratified by DCM severity. Changes in outcome measures that were statistically significant (P < .05) and met their respective minimum clinically important differences (MCIDs) were deemed clinically meaningful. Responder analysis was performed to compare the proportion of patients between DCM severity groups who met the MCID for each outcome measure. RESULTS: The cohort comprised 391 patients: 110 mild, 163 moderate, and 118 severe. At 12 mo after surgery, severe DCM patients experienced significant improvements in all outcome measures; moderate DCM patients improved in mJOA, NDI, EQ-5D, and PCS; mild DCM patients improved in EQ-5D and PCS. There was no significant difference between severity groups in the proportion of patients reaching MCID at 12 mo after surgery for any outcome measure, except NDI. CONCLUSION: At 12 mo after surgery, patients with mild, moderate, and severe DCM all demonstrated improved outcomes. Severe DCM patients experienced the greatest breadth of improvement, but the proportion of patients in each severity group achieving clinically meaningful changes did not differ significantly across most outcome measures.

Clinical predictors of achieving the minimal clinically important difference after surgery for cervical spondylotic myelopathy: an external validation study from the Canadian Spine Outcomes and Research Network.

OBJECTIVE: Recently identified prognostic variables among patients undergoing surgery for cervical spondylotic myelopathy (CSM) are limited to two large international data sets. To optimally inform shared clinical decision-making, the authors evaluated which preoperative clinical factors are significantly associated with improvement on the modified Japanese Orthopaedic Association (mJOA) scale by at least the minimum clinically important difference (MCID) 12 months after surgery, among patients from the Canadian Spine Outcomes and Research Network (CSORN). METHODS: The authors performed an observational cohort study with data that were prospectively collected from CSM patients at 7 centers between 2015 and 2017. Candidate variables were tested using univariable and multiple binomial logistic regression, and multiple sensitivity analyses were performed to test assumptions about the nature of the statistical models. Validated mJOA MCIDs were implemented that varied according to baseline CSM severity. RESULTS: Among 205 patients with CSM, there were 64 (31%) classified as mild, 86 (42%) as moderate, and 55 (27%) as severe. Overall, 52% of patients achieved MCID and the mean change in mJOA score at 12 months after surgery was 1.7 ± 2.6 points (p < 0.01), but the subgroup of patients with mild CSM did not significantly improve (mean change 0.1 ± 1.9 points, p = 0.8). Univariate analyses failed to identify significant associations between achieving MCID and sex, BMI, living status, education, smoking, disability claims, or number of comorbidities. After adjustment for potential confounders, the odds of achieving MCID were significantly reduced with older age (OR 0.7 per decade, 95% CI 0.5-0.9, p < 0.01) and higher baseline mJOA score (OR 0.8 per point, 95% CI 0.7-0.9, p < 0.01). The effects of symptom duration (OR 1.0 per additional month, 95% CI 0.9-1.0, p = 0.2) and smoking (OR 0.4, 95% CI 0.2-1.0, p = 0.06) were not statistically significant. CONCLUSIONS: Surgery is effective at halting the progression of functional decline with CSM, and approximately half of all patients achieve the MCID. Data from the CSORN confirmed that older age is independently associated with poorer outcomes, but novel findings include that patients with milder CSM did not experience meaningful improvement, and that symptom duration and smoking were not important. These findings support a nuanced approach to shared decision-making that acknowledges some prognostic uncertainty when weighing the various risks, benefits, and alternatives to surgical treatment.

High Speed, High Density Intraoperative 3D Optical Topographical Imaging with Efficient Registration to MRI and CT for Craniospinal Surgical Navigation.

Intraoperative image-guided surgical navigation for craniospinal procedures has significantly improved accuracy by providing an avenue for the surgeon to visualize underlying internal structures corresponding to the exposed surface anatomy. Despite the obvious benefits of surgical navigation, surgeon adoption remains relatively low due to long setup and registration times, steep learning curves, and workflow disruptions. We introduce an experimental navigation system utilizing optical topographical imaging (OTI) to acquire the 3D surface anatomy of the surgical cavity, enabling visualization of internal structures relative to exposed surface anatomy from registered preoperative images. Our OTI approach includes near instantaneous and accurate optical measurement of >250,000 surface points, computed at >52,000 points-per-second for considerably faster patient registration than commercially available benchmark systems without compromising spatial accuracy. Our experience of 171 human craniospinal surgical procedures, demonstrated significant workflow improvement (41 s vs. 258 s and 794 s, p < 0.05) relative to benchmark navigation systems without compromising surgical accuracy. Our advancements provide the cornerstone for widespread adoption of image guidance technologies for faster and safer surgeries without intraoperative CT or MRI scans. This work represents a major workflow improvement for navigated craniospinal procedures with possible extension to other image-guided applications.

Monitoring for myelopathic progression with multiparametric quantitative MRI.

BACKGROUND: Patients with mild degenerative cervical myelopathy (DCM) are often managed non-operatively, and surgery is recommended if neurological progression occurs. However, detection of progression is often subjective. Quantitative MRI (qMRI) directly measures spinal cord (SC) tissue changes, detecting axonal injury, demyelination, and atrophy. This longitudinal study compared multiparametric qMRI with clinical measures of progression in non-operative DCM patients. METHODS: 26 DCM patients were followed. Clinical data included modified Japanese Orthopedic Association (mJOA) and additional assessments. 3T qMRI data included cross sectional area, diffusion fractional anisotropy, magnetization transfer ratio, and T2*-weighted white/grey matter signal ratio, extracted from the compressed SC and above/below. Progression was defined as 1) patients' subjective impression, 2) 2-point mJOA decrease, 3) ≥3 clinical measures worsening ≥5%, 4) increased compression on MRI, or 5) ≥1 of 10 qMRI measures or composite score worsening (p < 0.004, corrected). RESULTS: Follow-up (13.5 ± 4.9 months) included mJOA in all 26 patients, MRI in 25, and clinical/qMRI in 22. 42.3% reported subjective worsening, compared with mJOA (11.5%), MRI (20%), comprehensive assessments (54.6%), and qMRI (68.2%). Relative to subjective worsening, qMRI showed 100% sensitivity and 53.3% specificity compared with comprehensive assessments (75%, 60%), mJOA (27.3%, 100%), and MRI (18.2%, 81.3%). A decision-making algorithm incorporating qMRI identified progression and recommended surgery for 11 subjects (42.3%). CONCLUSIONS: Quantitative MRI shows high sensitivity to detect myelopathic progression. Our results suggest that neuroplasticity and behavioural adaptation may mask progressive SC tissue injury. qMRI appears to be a useful method to confirm subtle myelopathic progression in individual patients, representing an advance toward clinical translation of qMRI.

Generating level-dependent models of cervical and thoracic spinal cord injury: Exploring the interplay of neuroanatomy, physiology, and function.

The majority of spinal cord injuries (SCI) occur at the cervical level, which results in significant impairment. Neurologic level and severity of injury are primary endpoints in clinical trials; however, how level-specific damages relate to behavioural performance in cervical injury is incompletely understood. We hypothesized that ascending level of injury leads to worsening forelimb performance, and correlates with loss of neural tissue and muscle-specific neuron pools. A direct comparison of multiple models was made with injury realized at the C5, C6, C7 and T7 vertebral levels using clip compression with sham-operated controls. Animals were assessed for 10weeks post-injury with numerous (40) outcome measures, including: classic behavioural tests, CatWalk, non-invasive MRI, electrophysiology, histologic lesion morphometry, neuron counts, and motor compartment quantification, and multivariate statistics on the total dataset. Histologic staining and T1-weighted MR imaging revealed similar structural changes and distinct tissue loss with cystic cavitation across all injuries. Forelimb tests, including grip strength, F-WARP motor scale, Inclined Plane, and forelimb ladder walk, exhibited stratification between all groups and marked impairment with C5 and C6 injuries. Classic hindlimb tests including BBB, hindlimb ladder walk, bladder recovery, and mortality were not different between cervical and thoracic injuries. CatWalk multivariate gait analysis showed reciprocal and progressive changes forelimb and hindlimb function with ascending level of injury. Electrophysiology revealed poor forelimb axonal conduction in cervical C5 and C6 groups alone. The cervical enlargement (C5-T2) showed progressive ventral horn atrophy and loss of specific motor neuron populations with ascending injury. Multivariate statistics revealed a robust dataset, rank-order contribution of outcomes, and allowed prediction of injury level with single-level discrimination using forelimb performance and neuron counts. Level-dependent models were generated using clip-compression SCI, with marked and reliable differences in forelimb performance and specific neuron pool loss.

Complications from the use of intrawound vancomycin in lumbar spinal surgery: a systematic review.

OBJECT The use of intrawound vancomycin is rapidly being adopted for the prevention of surgical site infection (SSI) in spinal surgery. At operative closure, the placement of vancomycin powder in the wound bed-in addition to standard infection prophylaxis-can provide high concentrations of antibiotics with minimal systemic absorption. However, despite its popularity, to date the majority of studies on intrawound vancomycin are retrospective, and there are no prior reports highlighting the risks of routine treatment. METHODS A MEDLINE search for pertinent literature was conducted for studies published between 1966 and May 2015 using the following MeSH search terms: "intrawound vancomycin," "operative lumbar spine complications," and "nonoperative lumbar spine complications." This was supplemented with references and known literature on the topic. RESULTS An advanced MEDLINE search conducted on May 6, 2015, using the search string "intrawound vancomycin" found 22 results. After a review of all abstracts for relevance to intrawound vancomycin use in spinal surgery, 10 studies were reviewed in detail. Three meta-analyses were evaluated from the initial search, and 2 clinical studies were identified. After an analysis of all of the identified manuscripts, 3 additional studies were included for a total of 16 studies. Fourteen retrospective studies and 2 prospective studies were identified, resulting in a total of 9721 patients. A total of 6701 (68.9%) patients underwent treatment with intrawound vancomycin. The mean SSI rate among the control and vancomycin-treated patients was 7.47% and 1.36%, respectively. There were a total of 23 adverse events: nephropathy (1 patient), ototoxicity resulting in transient hearing loss (2 patients), systemic absorption resulting in supratherapeutic vancomycin exposure (1 patient), and culture-negative seroma formation (19 patients). The overall adverse event rate for the total number of treated patients was 0.3%. CONCLUSIONS Intrawound vancomycin use appears to be safe and effective for reducing postoperative SSIs with a low rate of morbidity. Study disparities and limitations in size, patient populations, designs, and outcomes measures contribute significant bias that could not be fully rectified by this systematic review. Moreover, care should be exercised in the use of intrawound vancomycin due to the lack of well-designed, prospective studies that evaluate the efficacy of vancomycin and include the appropriate systems to capture drug-related complications.

High-resolution imaging of the central nervous system: how novel imaging methods combined with navigation strategies will advance patient care.

This narrative review captures a subset of recent advances in imaging of the central nervous system. First, we focus on improvements in the spatial and temporal profile afforded by optical coherence tomography, fluorescence-guided surgery, and Coherent Anti-Stokes Raman Scattering Microscopy. Next, we highlight advances in the generation and uses of imaging-based atlases and discuss how this will be applied to specific clinical situations. To conclude, we discuss how these and other imaging tools will be combined with neuronavigation techniques to guide surgeons in the operating room. Collectively, this work aims to highlight emerging biomedical imaging strategies that hold potential to be a valuable tool for both clinicians and researchers in the years to come.

Sources of delayed provision of neurosurgical care in a rural kenyan setting.

BACKGROUND: Delay to neurosurgical care can result in significant morbidity and mortality. In this study, we aim to identify and quantify the sources of delay to neurosurgical consultation and care at a rural setting in Kenya. METHODS: A mixed-methods, cross-sectional analysis of all patients admitted to the neurosurgical department at Kijabe Hospital (KH) was conducted: A retrospective analysis of admissions from October 1 to December 31, 2013 and a prospective analysis from June 2 to June 20, 2014. Sources of delay were categorized and quantified. The Kruskal-Wallis test was used to identify an overall significant difference among diagnoses. The Mann-Whitney U test was used for pairwise comparisons within groups; the Bonferroni correction was applied to the alpha level of significance (0.05) according to the number of comparisons conducted. IBM SPSS version 22.0 (SPSS, Chicago, IL) was used for statistical analyses. RESULTS: A total of 332 admissions were reviewed (237 retrospective, 95 prospective). The majority was pediatric admissions (median age: 3 months). Hydrocephalus (35%) and neural tube defects (NTDs; 27%) were most common. At least one source of delay was identified in 192 cases (58%); 39 (12%) were affected by multiple sources. Delay in primary care (PCPs), in isolation or combined with other sources, comprised 137 of total (71%); misdiagnosis or incorrect management comprised 46 (34%) of these. Finances contributed to delays in 25 of 95 prospective cases. At a median delay of 49 and 200.5 days, the diagnoses of hydrocephalus and tumors were associated with a significantly longer delay compared with NTDs (P < 0.001). CONCLUSION: A substantial proportion of patients experienced delays in procuring pediatric neurosurgical care. Improvement in PCP knowledge base, implementation of a triage and referral process, and development of community-based funding strategies can potentially reduce these delays.

Establishing a surgical partnership between Addis Ababa, Ethiopia, and Toronto, Canada.

BACKGROUND: Academic partnerships between high- and low/middle-income countries can improve the quality of surgical education and health care delivery in each setting. We report the perceived needs related to collaborative surgical education in a resource-limited setting. METHODS: We used qualitative methods to elicit the opinions of surgical faculty members and surgical residents and quantitative methods to outline surgical procedure type and volume. RESULTS: Ethiopian faculty members identified the management of trauma and emergency surgical care as a priority. They identified supervision in the operating room (OR), topic-specific lectures and supervising resident assessments in the clinic as appropriate roles for partners. Residents were in agreement with faculty members, highlighting a desire for supervision in the OR and topic-specific lectures. CONCLUSION: We present specific experiences and needs of a surgical teaching unit in a low-income country, paving the way to form a meaningful and responsive relationship between 2 surgical departments in 2 universities.

CONTEXTE: Les partenariats universitaires entre pays riches et pays à revenus faibles ou moyens peuvent améliorer l'enseignement de la chirurgie et la prestation des soins de santé dans chaque contexte. Nous faisons état des besoins perçus en matière de collaboration pour la formation en chirurgie dans un milieu aux ressources limitées. MÉTHODES: Nous avons utilisé des méthodes qualitatives pour sonder l'opinion des professeurs et des résidents en chirurgie, ainsi que des méthodes quantitatives pour faire le point sur les types d'opérations et leur volume. RÉSULTANTS: Les professeurs éthiopiens ont établi comme priorités la traumatologie et les soins chirurgicaux d'urgence. Ils ont évoqué la supervision au bloc opératoire, les conférences sur des thèmes précis et la supervision de l'évaluation clinique des résidents comme rôles appropriés pour les partenaires. Les résidents ont été du même avis que les professeurs et ont confirmé leur souhait d'être supervisés au bloc opératoire et d'entendre des conférences sur des thèmes précis. CONCLUSIONS: Nous présentons les expériences et les besoins particuliers d'une unité d'enseignement de la chirurgie dans un pays à faible revenu, et nous pavons ainsi la voie pour l'établissement d'un lien de collaboration important et pertinent entre les départements de chirurgie de 2 universités.

Review of speckle and phase variance optical coherence tomography to visualize microvascular networks.

High-resolution mapping of microvasculature has been applied to diverse body systems, including the retinal and choroidal vasculature, cardiac vasculature, the central nervous system, and various tumor models. Many imaging techniques have been developed to address specific research questions, and each has its own merits and drawbacks. Understanding, optimization, and proper implementation of these imaging techniques can significantly improve the data obtained along the spectrum of unique research projects to obtain diagnostic clinical information. We describe the recently developed algorithms and applications of two general classes of microvascular imaging techniques: speckle-variance and phase-variance optical coherence tomography (OCT). We compare and contrast their performance with Doppler OCT and optical microangiography. In addition, we highlight ongoing work in the development of variance-based techniques to further refine the characterization of microvascular networks.