Authors: Michael G. Fehlings, MD, PhD, FAANS, FRCS; Jetan Badhiwala, MD; Branko Kopjar, MD, PhD; Henry Ahn, MD, PhD; Francis Farhadi, MD, PhD; Christopher Shaffrey, MD; Ahmad Nassr, MD; Praveen Mummaneni, MD; Paul Arnold, MD; Bradley Jacobs, MD; K. Riew, MD; Darrel Brodke, MD (Toronto, Canada)
Introduction: Cervical spondylotic myelopathy (CSM) is the leading cause of spinal cord dysfunction. Surgical decompression is effective. Nonetheless, many patients suffer from significant residual disability. Based on preclinical evidence, we hypothesized that the sodium/glutamate blocking drug, riluzole, may enhance clinical outcomes following surgical decompression for CSM. Methods: In this multi-center, double-blinded, placebo-controlled randomized trial (ClinicalTrials.gov NCT01257828), adults (18-80 years) with moderately-severe CSM (mJOA 8-14) were assigned to surgical decompression plus riluzole (50 mg PO BID for 14 days before surgery and 28 days after surgery) or surgical decompression plus placebo. The primary outcome was change in mJOA score from baseline to 6 months post-operatively. Secondary outcomes included measures of function (Nurick grade), disability (NDI), QOL (SF-36, EQ-5D), neurological function (ASIA scores), grip strength, and pain (VAS). Outcomes were evaluated at enrollment, pre-operative hospital admission, 35 days, 6 months, and 1 year. Results: Two-hundred and ninety patients were enrolled (n=141 riluzole; n=149 placebo). Mean age was 58.0 ± 10.1 years. Subjects in both trial arms improved in all endpoints for functional status, disability, QOL, neurological function, grip strength, and pain. There was no difference between riluzole and placebo groups in change in mJOA at 6 months (2.45 vs. 2.82, respectively; P=0.16) or 1 year. Patients treated with riluzole showed a significantly greater reduction in pain (VAS) at 35 days than those who received placebo; this effect was maintained at 6 months and 1 year (P<0.05). There was a strong trend toward superior recovery in ASIA motor score with riluzole versus placebo at 1 year (P=0.053). Conclusion: Adjuvant treatment for 6 weeks peri-operatively with riluzole in the setting of CSM does not enhance functional recovery beyond surgical decompression, which dominates the clinical picture. However, the effects of riluzole in reducing pain in CSM patients are of clinical interest and merit further study.