Predictors of Return to Normal Neurological Function After Surgery for Moderate and Severe Degenerative Cervical Myelopathy: An Analysis of A Global AOSpine Cohort of Patients.

Abstract

Multiple studies have established the safety and efficacy of surgical intervention for degenerative cervical myelopathy (DCM). Although the main goal of surgery is symptom stabilization, a subset of patients achieves remarkable improvements. To identify predictors of return to normal neurological function after surgery for moderate or severe DCM. This is an analysis of 2 prospective multicenter studies (the AOSpine CSM-North America and CSM-International studies) conducted between 2005 and 2011. For patients with complete preoperative magnetic resonance imaging (MRI) and 2-yr follow-up, characteristics were compared between those who achieved a modified Japanese Orthopaedic Association (mJOA) score of 18 at 2 yr (no signs of myelopathy) vs controls. Only patients with baseline mJOA≤14 (moderate and severe myelopathy) were included to minimize ceiling effects. A total of 51 patients (20.3%) out of 251 with moderate or severe baseline myelopathy achieved an mJOA score of 18 at 2 yr. On stepwise multiple logistic regression analysis, T1-weighted (T1W1)-hypointensity (odds ratio [OR] 0.10; 95% confidence interval [CI], 0.01-0.79; P=.03) and longer walking time on the 30-m walking test (OR 0.95; 95% CI, 0.92-0.99; P=.03) were independent predictors of outcome, with an area under the curve of 0.71 for the model. In this study, T1W-hypointensity on MRI and longer walking time were found to predict a less likelihood of achieving return to normal neurological function after surgery for moderate or severe DCM. These findings may provide useful information for patient counseling and perioperative expectations.