Objective
To evaluate the efficacy of light-emitting diode (LED) and their dual-wavelengths as a treatment strategy for osteoarthritis.
Methods
We induced osteoarthritis in male Sprague-Dawley rats by intra-articular injection of sodium iodoacetate into the right rear knee joint. The animals with lesions were divided into an untreated group and an LED-treated group (n=7 each). In the LED-treated group, the lesioned knee was irradiated with lasers (850 and 940 nm) and dose (3.15 J/cm²) for 20 minutes per session, twice a week for 4 weeks. Knee joint tissues were stained and scanned using an in vivo micro-computed tomography (CT) scanner. Serum interleukin (IL)-6 and IL-18 levels were determined using enzyme-linked immuno-sorbent assay. Several functional tests (lines crossed, rotational movement, rearing, and latency to remain rotating rod) were performed 24 hours before LED treatment and at 7, 14, 21, and 28 days after treatment.
Results
LED-treated rats showed improved locomotor function and suppressed matrix-degrading cytokines. Micro-CT images indicated that LED therapy had a preserving effect on cartilage and cortical bone.
Conclusion
LED treatment using wavelengths of 850 and 940 nm resulted in significant functional, anatomical, and histologic improvements without adverse events in a rat model. Further research is required to determine the optimal wavelength, duration, and combination method, which will maximize treatment effectiveness.

Citations

• Effects of Dual Wavelength Photobiomodulation on Osseointegration in Grafted Areas
  Lucas de Sousa Goulart Pereira, Julia Raulino Lima, Elcio Marcantonio, Priscilla Barbosa Ferreira Soares, Suzane Cristina Pigossi, Guilherme José Pimentel Lopes de Oliveira
  Lasers in Surgery and Medicine.2026; 58(5): 429.     CrossRef
• BTEX-K Ameliorates Rheumatoid Arthritis Through Regulating the NF-κB and PPAR-γ Signaling Pathways in Incomplete Freund’s Adjuvant-Induced Arthritis Mice
  Joonpyo Hong, Jin-Ho Lee, Ga Young Lee, Jin-Hwan Oh, Hana Lee, Han Sung Kim, Tack-Joong Kim
  Biomedicines.2025; 13(7): 1524.     CrossRef
• Photobiomodulation Literature Watch December 2023
  James D. Carroll
  Photobiomodulation, Photomedicine, and Laser Surgery.2024; 42(10): 660.     CrossRef