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 motor 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 (I2). 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, I2 = 68 %, GRADE = low), improved physical function (g = 0.50, I2 = 67 %, GRADE = low), joint stiffness (g = -0.55, I2 = 31 %, GRADE = moderate) and increased range of motion (g = 0.76, I2 = 0 %, GRADE = moderate) but not walking speed (g = 0.38, I2 = 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.