Effects of Hip Abductor Muscle Strengthening Exercises in Patients with Osteoarthritic Knee Joints

OBJECTIVES: To study the effectiveness of hip abductor muscle strengthening exercises in people with medial compartment knee osteoarthritis.

Introduction: Osteoarthritis (OA) affects many joints including the large, weight bearing joints (hips and knees) and also the spine, hands, feet and shoulders. The knee is the most common weight bearing joint affected by OA, with the disease predominantly affecting the medial compartment of the tibiofemoral joint. Patients with knee OA frequently report symptoms of knee pain and stiffness as well as difficulty with activities of daily living such as walking, stair-climbing and house-keeping. Ultimately, pain and disability associated with the disease lead to a loss of functional independence and a profound reduction in quality-of-life.

Materials and Methodology: Study included 30 subjects with unilateral medial compartment knee OA, aged 45 years or above. The subjects were randomly divided into 2 groups. Group A subjects were given hip abductor muscle strengthening exercises&conventional physiotherapy treatment and Group B subjects were given conventional physiotherapy treatment alone. The subjects were treated for a period of 6 weeks, 6 days a week, once daily. Pain was assessed by VAS score and physical function was assessed by WOMAC Index of Osteoarthritis.

Results: The results were analyzed by Wilcoxon Signed-Rank Test. Group A showed significant improvement in pain (T=120, p<0.05) and physical function (T=120, p<0.05). In Group B, results showed significant improvement in pain (T=91, p<0.05) and physical function (T=120, p<0.05). Comparison of Group A and Group B was done with Wilcoxon Rank-Sum Test (Mann Whitney U Test), Group A showed significant improvement in pain (z = 2.82, p<0.0026) and physical function (z = 3.56, p<0.0002).

Conclusion: Hip abductor muscle strengthening exercises showed overall improvement in pain and physical function and is a useful adjunct exercise therapy in treating patients with unilateral medial compartment knee osteoarthritis.