A randomized comparative study between high-intensity laser vs low-intensity pulsed ultrasound both combined with exercises for the treatment of knee osteoarthritis

Abstract

Objective: To compare the effects of high-intensity laser therapy (HILT) plus exercise therapy (ET) vs low-intensity pulsed ultrasound (LIPUS) plus ET in knee osteoarthritis (KOA).

Methods: A single blinded randomized controlled trial in an outpatient setting. There were 60 participants with grades II and III KOA based on the radiological findings in Kellgren and Lawrence grading scale. Participants were allocated randomly into three groups, study group I (HILT+ET), study group II (LIPUS+ET), and control (ET) group. Participants in the three groups received active range of motion (ROM) exercises, muscle strengthening, and flexibility exercises. Treatment was administered 5 times/wk for two successive weeks. Primary outcomes involved visual analog scale (VAS), secondary outcomes involved knee ROM, proprioceptive accuracy and Western Ontario and McMaster Universities Arthritis Index scale. All outcomes were measured pre- and post-treatment.

Results: The mean age of participants was 55.4 ± 6.34, 55.2 ± 4.77 and 57 ± 6.39 years in HILT+ET, LIPUS+ET and control group respectively. There were statistically significant time-by-group effects (mixed-design multivariate analysis of variance) on all measured outcomes for all groups (P < .0001). However, HILT+ET yielded better improvement than the other groups (P < .0001). Between-group comparison revealed a significant difference in all measured outcomes between study group 1 vs study group 2, and between each study group vs the control group (P = .0001).

Conclusion: The effect of HILT combined with exercises achieved better results in pain, knee ROM, proprioceptive accuracy and functional disability than LIPUS combined with exercises and both are better than exercises only.

Keywords: exercises, knee osteoarthritis; high-intensity laser therapy; low-intensity pulsed ultrasound.