Shedding more light on the short-term effect of low-level laser therapy on pain in tendinopathy: A systematic review with meta-analysis

Background: In recent years, the effect of low level laser therapy (LLLT) on pain in tendinopathy has been increasingly evaluated in clinical trials. However, conflicting evidence regarding its use persists. Objective: The aim of this review is to evaluate the effect of LLLT on pain in the management of tendinopathy, and investigate the influence of LLLT parameters on the effect size of pain score. Methods: Searches of eight databases were conducted from inception to Jan 2025. Meta-analyses were conducted where possible, using either a fixed- or random-effects model, standardized mean differences (SMDs), and tests of heterogeneity. Multivariable meta-regression was performed to identify significant predictors of the effect size in pain score. Results: Thirty-five clinical controlled trials were identified and included in the meta-analyses. Compared to minimal intervention, LLLT provided superior pain relief in chronic tendinopathy, with pooled SMD -0.57(95% confidence interval [CI] -0.93 to -0.20, P = 0.002) after sensitivity analysis (15 RCTs, 299 participants in the experimental group and 282 participants in the control group). Additionally, the total number of sessions was a significant predictor of the effect size of pain relief (P < 0.05), after adjusting for age. Conclusions: LLLT is more effective than minimal intervention for pain relief in chronic tendinopathy. Greater total number of treatment sessions may be associated with a greater extent of pain relief. Other No funding was received for this review. PROSPERO registration number (CRD42021256567)