A randomized, placebo-controlled, double-blind study was designed to investigate the effectiveness of ultrasound therapy in primary knee osteoarthritis.
Ninety patients between 40 and 65 years of age having grade 2 and 3 bilateral knee osteoarthritis enrolled in the study were randomly assigned into 3 groups: continuous ultrasound, pulsed ultrasound, and placebo ultrasound. All patients were given a home exercise program. Patients were evaluated at baseline, at the end of the treatment, and at the second month after the treatment by a range of motion measurement, visual analog scale, Lequesne index for knee osteoarthritis, and Short Form-36 quality of life scale.
The increase in the knee range of motion was similar in both ultrasound groups, while the change in the placebo group was not statistically significant. Visual analog scale scores and Lequesne scores of the placebo group at the second month were significantly greater than both ultrasound groups' scores (P < 0.01 and P < 0.05, respectively).
Significant improvements in terms of pain, function, and quality of life scales were noted in both ultrasound groups in comparison with the placebo group. No statistically significant difference was found in terms of efficacy between the continuous and pulsed ultrasound.