Weber-Levine, Carly

OBJECTIVE Intramedullary spinal cord tumors (IMSCTs) are typically treated with maximal safe resection, during which neurosurgeons often monitor for neurological injury using muscle motor evoked potential (mMEP) and direct wave (D-wave) neuromonitoring. The predictive value of changes in D-waves for identifying motor outcomes is underexplored. This study evaluated the utility of D-waves for predicting postoperative motor deficits. METHODS Patients who underwent resection of a primary IMSCT with mMEP neuromonitoring from 2003 to 2023 at a tertiary care hospital were identified. Patients who underwent D-wave monitoring in addition to mMEP monitoring were compared to those who underwent mMEP monitoring alone using the Mann-Whitney U-test, chi-square test, and Fisher’s exact test. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of D-wave and mMEP monitoring for identifying new neurological deficits immediately postoperatively and at 1 month, 6 months, and last follow-up were calculated. RESULTS After matching, 125 patients were included (median age 42.0 years; 57.6% male; median follow-up 34.0 months), of whom 88 had both mMEP and D-wave data. The most common pathologies were ependymoma (64.0%) and astrocytoma (17.6%). Patients who did and did not undergo D-wave neuromonitoring had similar preoperative neurological function, primary pathology, tumor grade, and tumor location. D-wave use was associated with increased gross-total resection (88.6% vs 64.9%, p = 0.002) and reduced mortality (5.7% vs 24.3%, p = 0.007), length of stay (5.0 vs 6.0 days, p = 0.033), and 30-day readmission (2.3% vs 13.5%, p = 0.013) and reoperation (1.1% vs 10.8%, p = 0.012). At the 6-month follow-up, D-wave monitoring alone was superior to mMEP and combination monitoring for detecting new motor deficits. D-wave monitoring had peak sensitivity (77.8%) and NPV (96.5%) at 6 months and peak specificity (95.8%) and PPV (76.9%) in the immediate postoperative period. CONCLUSIONS D-wave monitoring was associated with reduced mortality and was more accurate than mMEP monitoring alone or combination monitoring for detecting new postoperative neurological deficits. Further prospective studies are needed to validate these results.

BACKGROUND AND OBJECTIVES: Social determinants of health (SDOH), such as education, insurance, race, and income, significantly affect a patient's medical care and surgical outcomes. Additional studies characterizing the impact of SDOH on patients undergoing spine surgery are needed. Accordingly, this study evaluates the impact of SDOH on severity of symptoms at presentation and discharge disposition in patients undergoing surgical treatment of cervical myelopathy. METHODS: A retrospective single-center study identified adult patients undergoing surgical intervention for cervical myelopathy between 2016 and 2020. Cohort characteristics were collected from patient medical records. The t -test, Wilcoxon rank-sum, analysis of variance, Kruskal-Wallis, and χ 2 tests were used to compare variables when appropriate. Multivariable linear and logistic regression analyses were conducted for modified Japanese Orthopaedic Association (mJOA) and discharge disposition. All statistical analysis was performed in MATLAB R2022b (MathWorks, Natick, MA). RESULTS: A total of 480 patients were included in the study with a male predominance of n = 281 (59%) and a mean age of 62 ± 13 years. Racial demographics included 64% White (n = 308) and 36% Non-White (n = 172) patients. On univariable analysis, mJOA at presentation was significantly associated with employment status ( P < .01), annual income ( P < .01), education level ( P < .01), and insurance status ( P = .03). On multivariable analysis, annual income and education level continued to be significant predictors of presenting mJOA. On univariable analysis, discharge disposition was associated with body mass index ( P = .01), mJOA at presentation ( P < .01), employment status ( P = .05), annual income ( P < .01), education level ( P < .01), insurance ( P < .01), approach ( P < .01), and length of stay ( P < .01). On multivariable analysis, mJOA at presentation, education level, insurance, and approach continued to be significant predictors of discharge disposition. CONCLUSION: SDOH affect the severity of symptoms at presentation and discharge disposition in patients undergoing surgery for cervical myelopathy. Understanding these dynamics and uncovering additional SDOH are critical for enhancing surgical care and achieving equitable healthcare outcomes.