Comparison of Mirror, Raw Video, and Real-Time Visual Biofeedback for Training Toe-Out Gait in Individuals With Knee Osteoarthritis

Objective: To compare performance error and perceived difficulty during toe-out gait modification in people with knee osteoarthritis (OA) across 3 different types of visual feedback: mirror, raw video, and real-time biofeedback of toe-out angle. Design: Repeated-measures, within-subject trial. Setting: University motion analysis laboratory. Participants: Individuals with knee OA (N=20; 11 women; mean age, 65.4 +/- 9.8y) participated in this study. Seven participants had mild knee OA, 9 had moderate knee OA, and 4 had severe knee OA. Interventions: Participants were trained to walk on a treadmill while matching a target indicating a 10 degrees increase in stance phase toe-out compared with toe-out angle measured during self-selected walking. The target was provided visually via the 3 types of feedback listed above and were presented in a random order. Main Outcome Measures: Kinematic data were collected and used to calculate the difference between the target angle and the actual performed angle for each condition (toe-out performance error). Difficulty was assessed using a numerical rating scale (0-10) provided verbally by participants. Results: Toe-out performance error was significantly less when using the real-time biofeedback method than when using the other 2 methods (P=.025; mean difference vs mirror=2.05 degrees; mean difference vs raw video=1.51 degrees). Perceived difficulty was not statistically different between the groups (P=.51). Conclusions: Although statistically significant, the 2 degrees difference in toe-out gait performance error may not necessitate the large economic and personnel costs of real-time biofeedback as a means to modify movement in clinical or research settings. (C) 2014 by the American Congress of Rehabilitation Medicine