Effectiveness of electromyographic biofeedback training on quadriceps muscle strength in osteoarthritis of knee †

The objective of this randomised controlled trial was to evaluate the effectiveness of electromyographic biofeedback as an add-on therapy with isometric exercise on quadriceps strengthening in patients with osteoarthritis of knee. Thirty three, 10 men and 23 women, patients with osteoarthritis of knee participated in the study. Patients were randomly placed into two groups: a biofeedback group (n = 17) and a control group (n = 16). The biofeedback group received electromyographic biofeedback-guided isometric exercise programme for 5 days a week for 5 weeks, whereas the control group received an exercise programme only. On between-group comparisons, the maximum isometric quadriceps strength in biofeedback group, at the end of 5th week was significantly greater than that of the control group (p < 0.004). The addition of electromyographic biofeedback to a 5-week isometric exercise program appeared to increase quadriceps muscle strength, compared to the exercise program alone for people with knee osteoarthritis. The finding, however, should be interpreted with caution due to limitations of the study design.