Effectiveness of hip abductor strengthening on health status, strength, endurance and six minute walk test in participants with medial compartment symptomatic knee osteoarthritis

BACKGROUND AND OBJECTIVES: Decreased activity of hip abductor musculature has been suggested as a contributing factor for the disease progression in participants with symptomatic knee osteoarthritis (OA). In this study, the effectiveness of 6 weeks isolated hip abductor strengthening on WOMAC, 6 minute walk test and hip strength and endurance in participants with symptomatic medial compartment knee OA were studied. MATERIAL AND METHOD: Thirty persons with medial compartment knee OA were randomized to hip abductor strengthening group (n = 15) and conventional group (n = 15). Both the groups received intervention for 5 times per week for 6 weeks. 6 minute walk test, health status (WOMAC), hip strength (by modified syphgmomanometer) and hip endurance (number of repetitions) were assessed at baseline and post intervention. The dependent variables were analyzed using 2 x 2 ANOVA, with repeated measurement as second factor to determine the effects of the intervention on each outcome variable. RESULTS: Significant group-by-time interactions were observed for each variable of interest. Post hoc testing revealed that all the outcome measures improved significantly in the hip abductor strengthening group following the 6-week intervention than the control group. CONCLUSION: The incorporation of hip-strengthening exercises may be considered along with conventional exercises when designing a rehabilitation program for persons with knee OA.