ELECTRODIAGNOSTIC PARAMETERS OF TIBIAL & SURAL NERVE IN LUMBAR SPINAL CANAL STENOSIS

Background: Lumbar spinal canal stenosis (LSCS) is dened as the narrowing of the lumbar spinal canal due to bulging intervertebral discs and/or hypertrophy of the ligamentum avum and facet joints that results in the compression of nerve root that might affect the nerve conduction studies. Objective: To determine the electrodiagnostic parameters of tibial and sural nerve with and severity of lumbar spinal canal stenosis. Methods: A comparative study was conducted on 51 patients of LSCS diagnosed clinically and canal diameter measured on MRI. All patients were subjected to nerve conduction study by EMG Octopus manufactured by Clarity Medical Pvt. Ltd. Results: The mean age of participants was 49.0±16.77 years ( 22-85 years), out of which 26 (50.98%) were males and 25 (49.02%) were females. They were divided into 3 groups based on antero-posterior lumbar canal diameter for severity of stenosis. LSCS was found at multiple levels in spinal cord with most common site is LSCS in L4-L5. There was a signicant decrease in motor nerve conduction (p=0.01(Rt. & Lt. tibial)) and sensory nerve conduction (p= 0.007(Rt. sural), 0.008 (Lt. sural)) velocities. However, signicant differences in motor and sensory latencies and amplitude were not observed. Conclusion: The signicantly reduced motor and sensory nerve conduction velocities are suggestive of functional impairement of the tibial and sural nerve with the severity of LSC; however, the non signicant changes in latencies and amplitude suggests no evidence of peripheral demyelination or axonal loss.