Prevalence of Electrodiagnostic Lumbosacral Nerve Root Involvement in Patients Presenting with Radicular Low Back Pain Referred to Physical Medicine and Rehabilitation Clinic of Imam Khomeini Hospital in Tehran, Iran, Within 2017 - 2020

Background: Low back pain is one of the most common causes of clinic referrals. In most patients, radicular pain results from the compression or injury of the proximal nerve root or dorsal root ganglion. Objectives: This study aimed to investigate the electrodiagnostic involvement of lumbar nerve roots in patients with lumbar radicular pain undergoing electromyography (EMG) and nerve conduction study. Methods: The sample population was selected from 18-70-year-old patients who had files in the clinic, complaining of lumbar pain radiating to the lower extremities for at least 2 months. Patient data were extracted from the available data and recorded in a separate anonymous information sheet. Results: This study was carried out on 352 patients with lumbar radicular pain. In addition to radicular pain, paresthesia was present in 86 patients (24.4%). Out of 352 patients with radicular pain, 294 cases (83.52%) showed unilateral or bilateral involvement in EMG. Among those who had paresthesia, 74 patients (86%) showed nerve root involvement in EMG. Conclusions: This study indicated the compatibility between lumbar radicular pain symptoms and the features observed in EMG, particularly in areas of paresthesia or the side of pain. Therefore, the patient’s symptoms can help predict nerve root involvement in the electrodiagnostic study before conducting this test.