Photobiomodulation Enhances Tendon Regeneration: A Systematic Review and Meta‐analysis of Preclinical Studies

Purpose To evaluate the preclinical evidence supporting the efficacy of photobiomodulation therapies in tendon regeneration. Methods A comprehensive literature search was conducted in MEDLINE, ScienceDirect, and Google Scholar to identify in vivo animal studies evaluating photobiomodulation therapies for tendon healing. Quantitative meta‐analyses were performed for homogeneous outcomes using a random‐effects model. Results Out of 4946 screened articles, 36 met the inclusion criteria. Pooled analyses revealed that photobiomodulation significantly downregulated proinflammatory IL‐1β (mean difference [MD] = −46.14 pg/mL; 95% confidence interval [CI] = −66.45 to −25.84; P < .00001) and upregulated anti‐inflammatory IL‐10 (MD = +49.14 pg/mL; 95% CI = 37.41‐60.86; P < .00001), indicating a bidirectional immunomodulatory effect. Histologically, photobiomodulation increased the collagen type I/III ratio (standardized MD = +3.0; 95% CI = 2.4‐3.6). Functionally, load‐bearing strength improved significantly compared with controls (MD = +10.07 N; 95% CI = 3.01‐17.13; P = .005) with photobiomodulation (low‐level laser therapy and light‐emitting diode), whereas photochemical tissue bonding showed higher tensile strength (MD = +0.57 MPa; 95% CI = 0.37‐0.78; P < .00001), reflecting enhanced early mechanical stabilization through sutureless photochemical repair. Conclusions Photobiomodulation therapies promote tendon regeneration in both acute and chronic injury models, enhancing tendon regeneration at molecular, histological, and functional levels. Clinical Relevance These findings support the potential of photobiomodulation therapies, providing a foundation for clinical trials in human populations to refine rehabilitation protocols and improve musculoskeletal outcomes.