Efficacy of EMG-biofeedback in knee osteoarthritis

This study was designed to investigate the additive effect of EMG-biofeedback in rehabilitation of knee osteoarthritis. Forty patients, aged 45-70, with the diagnosis of knee osteoarthritis according to American College of Rheumatology (ACR) criteria were taken into the study. The patients were randomly assigned in two groups. One group (n = 20) received strengthening exercise program with EMG-biofeedback while the other group (n = 20) had the same exercise program without biofeedback for 3 weeks. The clinical outcome was assessed on the basis of pain with visual analog scale (VAS), function with Western Ontario McMaster Osteoarthritis Index (WOMAC) and quality of life with Nottingham Health Profile (NHP). Quadriceps strength was measured with Cybex isokinetic dynamometer, isokinetically at the angular velocities of 60 and 180A degrees/s and isometric strength at 65A degrees of knee flexion. Pain, WOMAC scores and muscle strength improved in both groups but there was no statistically significant differences between two groups (p > 0.05). In both groups physical mobility, pain scores of NHP improved significantly (p < 0.001) while in EMG-biofeedback group energy and sleep scores also improved after treatment (p < 0.05). As reported in the literature, in our study, strengthening exercises improved pain, function, muscle strength and quality of life in patients with knee osteoarthritis. But it seems that there is no significant additive effect of EMG-biofeedback to regular strengthening exercise program in these patients.