Ultrasound plus low-level laser therapy for knee osteoarthritis rehabilitation: a randomized, placebo-controlled trial

Abstract

This study evaluated the synergistic effects of ultrasound (US) and low-level laser therapy (LLLT) with or without therapeutic exercises (TE) in women with knee osteoarthritis. Forty-two Caucasian women with knee osteoarthritis were allocated into three groups: (1) the placebo group who did not perform TE, but the prototype without emitting light or ultrasonic waves was applied, (2) the US + LLLT group in which only the prototype was applied and (3) the TE + US + LLLT group that performed TE before the prototype was applied. However, 35 women completed the full clinical trial. Pressure pain thresholds (PPT) using an algometer and functional performance during the sit-to-stand test were carried out. The average PPT levels increased for US + LLLT (41 ± 9 to 54 ± 15 N, p < 0.01) and TE + US + LLLT (32 ± 8 to 45 ± 9 N, p < 0.01) groups. The number of sit-to-stands was significantly higher for all groups. However, the change between pre-treatment and post-treatment (delta value) was greater for the US + LLLT (4 ± 1) and TE + US + LLLT groups (5 ± 1) than for the placebo group (2 ± 1) with a significant intergroup difference (p < 0.05). This study showed reduced pain and increased physical functionality after 3 months of US + LLLT with and without TE.

Keywords: Knee; Laser therapy; Osteoarthritis; Pain; Ultrasound.