The Effect of adding Hip Abductor Strengthening to Conventional Rehabilitation on Muscular Strength and Physical Function following Total Knee Replacement

Objective: This study aimed to investigate the effect of adding hip abductor strengthening to conventional rehabilitation on muscle strength and physical function following total knee replacement (TKR) for knee osteoarthritis. Design: Randomized controlled trial Methods: Thirty-five participants were randomly allocated to exercise groups I (n=18) and II (n=17). Group I underwent hip abductor training and conventional rehabilitation for 30 min per day, 5 days per week for 4 weeks. Group II underwent conventional rehabilitation for 30 min per day, 5 days per week for 4 weeks. The participants in both groups also received continuous passive motion therapy for 15 min per day, 5 days per week for 4 weeks. To investigate the effect of the intervention, the Biodex dynamometer was used to measure the peak torque of both knee extensors and hip abductors. This study used the Knee Outcome Survey-Activities of Daily Living Scale (KOS-ADLS) to assess physical function, as well as the figure-of-8 walk test (F8W) and the stair climb test (SCT). Results: According to the interventions, exercise groups I and II showed significantly improved muscle strength and KOS-ADLS, F8W, and SCT scores (p＜0.001). Compared with that of exercise group II, exercise group I showed significantly improved hip abductor strength (p＜0.001) and KOS-ADLS, F8W, and SCT scores (p＜0.05). Conclusions: The results of this study indicate that the combination of hip abductor strengthening and conventional rehabilitation is an effective exercise method to increase hip abductor muscle strength and physical function after TKR.