The Healing Effect of Photobiomodulation on Venous Leg Ulcers: A Systematic Review and Meta-Analysis.

Venous leg ulcers are common, costly and often slow to heal despite standard management. Photobiomodulation has been proposed as an adjuvant therapy to enhance wound repair. This systematic review and meta-analysis aimed to evaluate the effect of photobiomodulation on healing outcomes in venous leg ulcers. A comprehensive search of PubMed, Embase, Web of Science and Cochrane Library (1990-2024) identified randomised controlled trials evaluating photobiomodulation in adults with venous leg ulcers. Two reviewers independently screened studies (n = 3824) and assessed eligibility according to predefined inclusion and exclusion criteria (n = 34). Data were extracted from the included studies (n = 11), and the risk of bias was assessed using the Cochrane RoB 2 tool. A random-effects meta-analysis was conducted for the absolute change in ulcer area. Eleven trials were included, comprising 615 randomised patients, where 340 had venous leg ulcers. Patients who completed follow-up contributed to the healing outcomes (intervention n = 169, controls n = 167). All studies were evaluated to have some or high concerns for risk of bias. Four trials contributed data to the meta-analysis showing that photobiomodulation did not significantly reduce ulcer area compared with controls (Mean Difference 3.77 cm2, 95% CI -4.45 to 11.99; p = 0.37) and heterogeneity was substantial (τ2 = 65.37; I2 = 96%). Current evidence does not demonstrate a statistically significant benefit of photobiomodulation on venous leg ulcer healing. High heterogeneity, small sample sizes and methodological limitations reduce confidence in the pooled estimate. Standards for photobiomodulation therapy in venous leg ulcers are still missing, and well-designed RCTs are needed to clarify the therapeutic potential of photobiomodulation.