Objective: To evaluate the effects of isokinetic exercise versus a program of patient education on pain and function in older persons with knee osteoarthritis.
Design: A randomized, comparative clinical trial, with interventions lasting 8 weeks and evaluations of 12 weeks.
Setting: An outpatient Veterans Affairs Medical Center clinic and an affiliated university hospital.
Patients: One hundred thirteen men and women between 50 and 80 years old with diagnosed osteoarthritis of the knee; 98 completed the entire assigned treatment.
Intervention: Patients received either a regimen of isokinetic exercise of the quadriceps muscle three times weekly over 8 weeks or a series of 4 discussions and lectures led by health care professionals.
Main outcome measures: Variables studied for change were isokinetic and isometric quadriceps strength, pain and function determined by categorical and visual analog scales, and overall status using physician and patient global evaluations by the Arthritis Impact Scale, version 2, Western Ontario McMaster's Arthritis Index, and Medical Outcome Study Short Form 36.
Results: Both treatment groups showed significant strength gains (p < .05), which occurred over a wider velocity spectrum for the exercise group. Exercised patients also had improved pain scores for more of the variables measured than those receiving education. Both groups had positive functional outcomes and slightly improved measures of overall status.
Conclusions: Isokinetic exercise is an effective and well-tolerated treatment for knee osteoarthritis, but a much less costly education program also showed some benefits.