Impact of Preoperative Intramedullary T2 Signal Intensity Changes on Surgical Outcomes in Cervical Spondylotic Myelopathy

Study Design. Multicenter prospective cohort study. Objective. To evaluate the impact of preoperative intramedullary T2 signal intensity (SI) changes on surgical outcomes in patients with cervical spondylotic myelopathy (CSM). Summary of Background Data. Intramedullary SI on T2-weighted MRI has been considered a predictor of poor outcomes in CSM; however, its prognostic value remains controversial. Methods. We prospectively analyzed 721 patients with CSM who underwent surgical decompression at 10 institutions between 2019 and 2022. Patients were classified into SI (+) and SI (−) groups based on preoperative T2-weighted MRI. Outcomes were assessed preoperatively and at 2 years using the Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS), JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), and Short Form-36 (SF-36). Multivariable analyses were adjusted for age, sex, symptom duration, preoperative C2–7 angle, cervical range of motion, diabetes mellitus, and smoking history. Results. Of the 721 patients, 554 (76.8%) were SI (+) and 167 (23.2%) were SI (−). Although preoperative upper extremity pain/numbness on VAS was significantly higher in the SI (+) group (64.7 vs. 58.9, P =0.037), this difference was not significant at 2 years. No significant between-group differences were found in preoperative or postoperative JOA score, JOA recovery rate, ΔJOA, SF-36, JOACMEQ effectiveness rates, or perioperative complications. SI was not independently associated with improvement in any JOACMEQ domain. Only the preoperative C2–7 angle was independently associated with the presence of SI (odds ratio, 1.02; P =0.023). Conclusion. Preoperative intramedullary T2 SI was associated with greater preoperative upper extremity pain/numbness, and with a greater preoperative C2–7 angle. However, after adjustment for confounders, the binary presence of intramedullary T2 SI was not statistically significantly associated with worse 2-year neurological, functional, or patient-reported outcomes. Level of Evidence. Level II