Efficacy of low level laser on knee osteoarthritis treatment

  Introduction: Osteoarthritis (OA) is the most common disease in all joints that is generally treated with drugs such as non-steroidal anti-inflammatory drugs (NSAIDs) and physiotherapy. Although NSAIDs are widely used to treat the pain and stiffness associated with knee OA, the high incidence of serious upper gastrointestinal side effect with NSAIDs can limit their use. Therefore physiotherapy plays a vital role on OA treatments. One modality that has mostly used recently is low level laser. Despite its widespread usage, the results of the experimental and clinical studies are conflicting. However, very few controlled clinical studies of low-power laser applied for the treatment of knee OA have been reported and the findings of these studies are also contradictory. This study was performed to assess the effects of low level laser on knee OA.   Material and Methods: This single-blinded clinical trial was performed on 36 adult patients (45-75 years old) with knee OA. The patients were randomly divided into two groups of active laser with standard treatment and placebo laser with standard treatment. A Gal-Al-As diode laser device with a power output of 30 mW and a wavelength of 830 nm was used in the study. The standard treatment was ultrasound¸ transcutaneous electrical nerve stimulation, infrared¸ the straight-leg raise test in supine position, and the subjects were treated for ten sessions¸ 5 times per week and for a period of two weeks. Then pain at rest, duration of morning stiffness, active range of knee flexion and the quality of life with WOMAC index were assessed before and after the intervention.   Results: Although, there were significant differences before and after the intervention of all criteria in both groups (p