Therapeutic effects of short-term monochromatic infrared energy therapy on patients with knee osteoarthritis: a double-blind, randomized, placebo-controlled study.

STUDY DESIGN: Randomized, double-blind, placebo-controlled study.

OBJECTIVES: To examine the short-term therapeutic effects of monochromatic infrared energy (MIRE) on participants with knee osteoarthritis (OA). Patients were assessed according to the International Classification of Functioning, Disability and Health.

BACKGROUND: MIRE is commonly used in therapy for patients with peripheral neuropathies. However, research has not focused intensively on the therapeutic effects of MIRE in patients with knee OA.

METHODS: This study enrolled 73 participants with knee OA. Participants received six 40-minute sessions of active or placebo MIRE treatment (890-nm wavelength; power, 6.24 W; energy density, 2.08 J/cm2/min; total energy, 83.2 J/cm2) over the knee joints for 2 weeks. International Classification of Functioning, Disability and Health-related outcomes were collected weekly over 4 weeks using the Knee injury and Osteoarthritis Outcome Score, Lysholm Knee Scale, Hospital Anxiety and Depression Scale, Multidimensional Fatigue Inventory, Chronic Pain Grade questionnaire, World Health Organization Quality of Life-brief version, and OA Quality of Life Questionnaire. Data were analyzed by repeated-measures analysis of variance.

RESULTS: No statistically significant differences were found for the interaction of group by time for Knee injury and Osteoarthritis Outcome Score scores, including pain, other symptoms, function in daily living, function in sport and recreation, and knee-related quality of life. Scores on the Lysholm Knee Scale, Hospital Anxiety and Depression Scale, Multidimensional Fatigue Inventory, Chronic Pain Grade questionnaire, World Health Organization Quality of Life-brief version, and OA Quality of Life Questionnaire also showed no significant differences between the 2 groups at any of the 4 follow-up assessments.

CONCLUSION: Short-term MIRE therapy provided no beneficial effects to body functions, activities, participation, and quality of life in patients with knee OA.