A home-based program of simple quadriceps exercises reduces knee pain and improves knee function in overweight people with knee pain

Abstract

Does a program of quadriceps exercises or dietary advice, or both, reduce knee pain and improve knee function in people living in the community with knee pain? Factorial, randomised, controlled trial. Five general practices in the United Kingdom with interventions delivered through home visits. Community dwellers aged at least 45 years, who were overweight or obese (BMI ≥ 28) and complained of knee pain on most days of the past month. Randomisation of 389 participants allotted 82 to the quadriceps exercise group, 122 to the dietary advice group, 109 to the quadriceps exercise and dietary advice group, and 76 to a control group. The exercise groups were taught the exercises at home by a dietitian and received up to 6 further home visits over 24 months. Exercise participants were asked to complete ≥ 2 exercises a day, with 5 to 20 repetitions of each exercise. The exercises progressed from quadriceps setting exercises, to exercises with elasticised bands, to functional activities such as stepping up and down off a step. The dietary groups received individualised advice to reduce weight, newsletters with recipe ideas, and one home visit per month over 24 months. The control group received an advice leaflet. The primary outcome was pain reduction by ≥ 30% on the pain subscale of the Western Ontario McMaster (WOMAC) osteoarthritis index at 24 months. Secondary outcome measures were change in the WOMAC pain, stiffness, and physical function subscales, hospital anxiety and depression rating scale, and the bodily pain and physical function domains of the Short Form 36 (SF-36). 289 (74%) participants completed the study. At 24 months, those in the exercise groups were more likely to experience > 30% reduction in pain compared to the non-exercise groups (relative risk 1.36, 95% CI 1.05 to 1.76) with number needed to treat of 9 (95% CI 5 to 55). Compared to the non-exercise groups the exercise groups showed improvement in WOMAC physical function of −3.64 units (95% −6.01 to −1.27), WOMAC stiffness (−0.35 units, 95% CI −0.66 to −0.03), and improvements in the SF-36 subscales of bodily pain and physical function. The dietary advice groups lost weight (2.95 kg, 95% CI 1.44 to 4.46 kg) and reduced depression at 24 months compared to the non-dietary groups, but showed no evidence of an effect on any other outcomes. A 2-year homebased quadriceps exercise program reduced knee pain and increased knee function in overweight and obese people with knee pain. The effect size was moderate. Dietary advice resulted in a modest weight loss that did not change pain or function, but did reduce depression.