Postoperative Follow-up Study of F-wave and H-reflex on Lumbosacral Radiculopathy Caused by Disc Herniation

ABSTRACT

OBJECTIVE: To explore the clinical value of postoperative follow-up examination of F-wave and H-reflex in patients with lumbosacral radiculopathy and to clarify optimal timing of follow-up examination. METHOD: The subjects were 17 patients with unilateral lumbosacral radiculopathy caused by disc herniation. In patients with the L5 radiculopathy, F-waves were obtained from extensor digitorum brevis and six parameters including minimal latency per height were used. In patients with the S1 radiculopathy, H-reflexes were obtained from gastrocnemius and amplitude and minimal latency were used as parameters. These parameters were evaluated preoperatively and postoperatively at week 1, 3, 6. These changes of the parameters and clinical findings were related. RESULTS: The parameters of peroneal F-wave and tibial H-reflex showed significant improvement at 3 weeks and 6 weeks after surgery. The improvements of these parameters were not related with clinical improvement at 1 week after operation, but these were significantly related with improvement of pain and muscle weakness at 3 weeks after operation. CONCLUSION: These findings suggested that follow-up examination of F-wave and H-reflex were valuable for objective assessment of lumbosacral radiculopathy after operation and the optimal timing for follow-up study was 3 weeks after operation.