Quantification of Rossolimo reflexes: A sensitive marker for spondylotic myelopathy

Abstract

Study design: Prospective study. Objectives: To assess and quantify Rossolimo reflexes using an electrophysiological test, and correlate the findings with the severity of spinal cord dysfunction in cervical and thoracic spondylotic myelopathy (CTSM). Setting: A university neurorehabilitation center. Methods: We enlisted 42 patients with CTSM between the fifth cervical and the ninth thoracic cord levels. Using electrophysiological assessments, Rossolimo reflexes were evaluated in all patients. Conduction latencies and amplitude of muscle action potentials (MAPs) of the reflexes were measured, analyzed and compared with the grading of spinal cord dysfunction and the cord compression ratios. Results: We found a high diagnostic sensitivity of quantified Rossolimo reflex in patients with CTSM. A positive correlation exists between the MAP amplitude of Rossolimo reflexes and the different grades of spinal cord dysfunction. A negative linear relationship was found between the MAP amplitude of Rossolimo reflexes and the cord compression ratios in CTSM patients. Conclusion: Rossolimo reflexes can be measured by electrophysiological assessments, and we demonstrate a quantification method for an established neurological sign. Not only is the Rossolimo reflex found to be a highly sensitive test in clinical neurological examination but the electrophysiological assessment for this reflex can also serve as an objective marker for evaluation of the severity of spinal cord dysfunction in CTSM. Spinal Cord (2011) 49, 211-214; doi: 10.1038/sc.2010.81; published online 13 July 2010