Effects of laser acupuncture on pain and motor function in musculoskeletal disorders: A systematic review and meta-analysis

Background Evidence suggests laser acupuncture (LA) may relieve pain and improve motor function in musculoskeletal disorders (MSDs), but the relationship between these outcomes is unclear. Objectives To (1) evaluate the effects of LA on pain and motor function outcomes in MSDs; (2) examine associations between pain modulation and function; and (3) explore the impact of treatment characteristics. Methods Ten databases were searched. Pooled effects were evaluated using Hedge’s g ( g ) through random-effects meta-analysis models, with subgroup analyses exploring heterogeneity ( I 2 ). Meta-regression was conducted to examine the influence of treatment characteristics and associations between pain and motor outcomes. GRADE approach assessed the certainty of evidence. Results Nineteen studies with 1816 participants were included. LA significantly reduced pain intensity ( g = 0.59, I 2 = 68%, GRADE = low), improved physical function ( g = 0.50, I 2 = 67%, GRADE = low), joint stiffness ( g = -0.55, I 2 = 31%, GRADE = moderate) and increased range of motion ( g = 0.76, I 2 = 0%, GRADE = moderate) but not walking speed ( g = 0.38, I 2 = 65%, GRADE = low). Meta-regression showed that LA wavelength was significantly associated with pain relief ( β = -3.77) and stiffness improvement ( β = -3.07). However, pain relief was not associated with improvements in motor function. Conclusions LA offers a non-invasive and effective approach for pain management and motor function performance, with wavelength as a key moderator. Functional benefits appear independent of analgesia, suggesting a feasible alternative for patients unable to tolerate exercise-based rehabilitation.