Histopathology Findings of Low-Level Laser Therapy Effectiveness on Achilles Tendon Repair in Rabbit Model.

Abstract

BACKGROUND: Low-level laser therapy (LLLT) has been utilized to treat tendinitis and various other musculoskeletal conditions. The current study assessed the impact of LLLT (650 and 750&#xa0;nm) on tendon repair in rabbits. MATERIALS AND METHODS: Fifteen 2-year-old male New Zealand White rabbits were divided into three groups: control, 650&#xa0;nm laser and 750&#xa0;nm laser therapy. After applying Achilles tendon-destructive surgery on their right legs, rabbits underwent LLLT, and tendon repair was assessed using histopathology and immunohistochemistry (IHC) findings. All data were analysed using SPSS version 21, considering a significant level <0.05. RESULTS: The study's histopathological and immunohistochemical analysis revealed that LLLT at 650 and 750&#xa0;nm significantly improved tendon healing compared to the control group (p&#xa0;<&#xa0;0.05). The treated groups exhibited better organized tendon fibres with reduced discontinuity, collagen fibre waviness, and inflammatory response (p&#xa0;<&#xa0;0.05). Both laser wavelengths showed similar results with no significant differences between them (p&#xa0;>&#xa0;0.05), but both were notably better than the control group in reducing inflammation, enhancing fibre structure, and lowering levels of collagen type I (Col-I); collagen type III (Col-III); transformer growth factor beta (TGF-&#x3b2;); galectin-3 (galectin-3); VGF nerve growth factor inducible; vascular endothelial growth factor (VEGF), indicating a more effective healing process with LLLT. CONCLUSION: Due to our findings, LLLT at 650 and 750&#xa0;nm effectively reduced inflammation, improved structural integrity, and enhanced the organization of collagen fibres for Achilles tendon repair in rabbits.