Evaluating Postoperative Muscle Strength Using Surface Electromyography in Hip Fracture Patient

BACKGROUND: To compare the muscle strength of patients with a hip fracture according to the presence of sarcopenia after surgery and the correlation of measured values between a Biodex and surface electromyography (sEMG) in postoperative measurement of muscle strength. METHODS: Seventy-one patients who underwent hip fracture surgery were included in this study. Muscle mass was measured using dual energy X-ray absorptiometry and the grip strength was evaluated using a dynamometer. The diagnosis of sarcopenia followed the Asian Working Group for Sarcopenia criteria. We evaluated the Biodex to assess muscle strength according to the presence of sarcopenia and at the same time measured the sEMG to evaluate the correlation of muscle strength between Biodex and sEMG. RESULTS: We assigned 34 patients with sarcopenia and 37 without sarcopenia to 2 groups. In the comparison of muscle strength using Biodex and sEMG between the 2 groups, it was confirmed that muscle strength of sarcopenia group was decreased compared with that of the non-sarcopenia group, although there was no statistical significance between the groups. However, Biodex and sEMG showed very close correlation with muscle strength in all variables. CONCLUSIONS: We suggest that using sEMG for the evaluation of muscle strength after hip fracture surgery may be an excellent tool alternative to isokinetic testing machines such as the Biodex.