Objectives: To examine the efficacy of electromyographic (EMG) biofeedback supplementation to exercise rehabilitation for people with patellofemoral pain syndrome.
Design: Double-blinded randomized clinical controlled pilot trial.
Setting: Clinical setting with home programme.
Participants: Twenty-six subjects diagnosed with patellofemoral pain.
Intervention: Subjects were randomly assigned into EMG biofeedback+exercise group or exercise-only group. All subjects participated in an eight-week home exercise programme, while the biofeedback group also received EMG visual feedback of their quadriceps muscle activities during the exercises.
Main outcome measures: Isokinetic knee extension strength, patellar alignments and perceived pain severity were assessed in weeks 0, 4 and 8 for all subjects. The data within and between groups were compared by repeated measures ANOVA with aα=0.05.
Results: Both groups improved in isokinetic peak torque (P=0.005), work output (P=0.037) and patellar alignments (P=0.001-0.014). Besides, there was a trend of decrease in pain (P=0.088). The biofeedback group improved faster than the exercise group in lateral patellar rotation and peak torque per body weight, although no statistically significant difference was shown.
Conclusion: Biofeedback supplement to the exercise programme might hasten the improvement for subjects with patellofemoral pain in the first few weeks of a physiotherapy exercise programme, but this needs further study before being used.
