Low Level Laser Therapy in Knee Osteoarthritis: A Narrative Review

Knee osteoarthritis (KOA) is the most common musculoskeletal disorder, especially in middle up to old age. KOA also results in many complications like changes in gait. Nowadays, changes in lifestyle and the reduced physical activity make people more vulnerable to KOA. Therefore, considering the increasing prevalence of KOA in many societies and the costs imposed on the afflicted people and their governments, providing conservative management approaches with a view to saving time and money is important. There are an assortment of conservative strategies in the management of KOA including low level laser therapy (LLLT). Since the introduction of lasers in the medical field in 1960, various types of lasers with widespread administration programs are used for medical conditions from cosmetics to surgery. However, there are conflicting findings on the application of lasers in osteoarthritis. To discuss the basis of the highest level of evidence, only systematic reviews with or without meta-analyses published up to January 2019 were included in the present work. In this regard, Scopus, PEDro, Medline, ISI Web of Science, Cochrane, PubMed, Irandoc, Iran Medex, Magiran, and SID were searched to retrieve articles in English or Persian. A total of 22 systematic reviews and meta-analyses were found, 14 of which were included in this study. The accepted articles were published between 1991 and up to 2019. The purpose of this narrative review was to investigate the effect of LLLT on pain and function in subjects with KOA. The result of the present review may help clinicians in making evidence-based decisions on optimal care in relation to administering LLLT.