The Mechanisms and Efficacy of Photobiomodulation Therapy for Arthritis: A Comprehensive Review

Zhang R, Qu J · International Journal of Molecular Sciences

A mechanism-and-method review from a biomedical optics group. It frames photobiomodulation as a photobiological rather than photothermal response — light absorbed by the cell regulating its functional response, distinct from heating — and traces the anti-inflammatory effect through that route. It catalogues how the small-animal arthritis models are constructed and reviews the outcome measures clinical trials have used to judge the therapy, noting that some rely on questionnaire responses. The authors state there is no universally agreed optimal parameter set, that wavelength, dose, power density, irradiation time and treatment site all remain open questions, and that future trials should adopt standardised evaluation methods.

Population

Cell studies, small-animal arthritis models and clinical trials of photobiomodulation in rheumatoid arthritis and osteoarthritis together

Intervention

Near-infrared light from lasers or LEDs, across an unstandardised range of wavelength, dose, power density, irradiation time and treatment site

Comparator

Sham irradiation or untreated arthritis controls, varying by included study

Limitations

A narrative review with no stated search strategy, no risk-of-bias assessment and no pooling. It treats rheumatoid arthritis and osteoarthritis as one subject throughout, so a claim taken from it may rest on the disease the reader does not have. Its clinical section reviews how trials were evaluated more than what they found, and it reports no effect sizes. Chinese national and Shenzhen municipal funding; the authors declare no commercial or financial relationships.