Comparison of Photobiomodulation and Anti-Inflammatory Drugs on Tissue Repair on Collagenase-Induced Achilles Tendon Inflammation in Rats

Author(s)

Naterstad, Ingvill Fjell ^[1] ; Rossi, Rafael Paolo ^[2] ; Marcos, Rodrigo Labat ^[3] ; Parizzoto, Nivaldo Antonio ^[4] ; Frigo, Lucio ^[5] ; Joensen, Jon ^[1] ; Leonardo Lopes Martins, Patricia Sardinha ^[6] ; Bjordal, Jan Magnus ^[1] ; Brandao Lopes-Martins, Rodrigo Alvaro ^{[6, 7]}

Affiliation

^[1] Univ Bergen, Dept Global Publ Hlth & Primary Care, Physiotherapy Res Grp, N-5020 Bergen - Norway

^[2] Univ Sao Paulo, Inst Biomed Sci, Postgrad Program Pharmacol, Sao Paulo - Brazil

^[3] Univ Nove Julho, Postgrad Program Biophoton Appl Hlth Sci, Sao Paulo - Brazil

^[4] Univ Fed Sao Carlos, Dept Physiotherapy, Sao Paulo - Brazil

^[5] Univ Cruzeiro Sul, Dept Hlth Sci, Sao Paulo - Brazil

^[6] Univ Mogi das Cruzes, Postgrad Program Biomed Engn, Technol Res Ctr, Sao Paulo - Brazil

^[7] Univ Brasil, Dept Bioengn, Sao Paulo - Brazil

• Document type: Journal article
• Source: Photomedicine and Laser Surgery; v. 36, n. 3, p. 137-145, MAR 2018.
• Web of Science Citations: 2

Abstract

Background: Tendinopathy is characterized by pain, edema, and structural changes in tendon tissue. Objective: In this animal study we decided to compare the short- and medium-term effects of low-level laser therapy (LLLT), dexamethasone, and diclofenac on inflammation and tendon tissue repair in collagenase-induced tendinitis. Materials and methods: Two hundred five female Wistar rats were randomly divided into five groups. Animals in the control group were given a saline injection and the experimental groups received a collagenase injection (100g/tendon) in the peritendinous Achilles and received no treatment, LLLT (3J, 810nm, 100mW), diclofenac (1.1mg/kg), or dexamethasone (0.02mg/kg). Histological analyses were performed at 10 time points up to 60 days (n=5/group each time point), and included an assessment of the severity of inflammation, collagen fiber content, and organization. Results: Collagenase injection induced a severe inflammatory reaction with significant reduction in collagen content for 48h, and disorientation of collagen fibers lasting between 14 and 21 days. Diclofenac and dexamethasone reduced inflammatory signs during the first 2 days, although there was prolongation of the inflammatory phase and slower normalization of tendon quality, particularly in the dexamethasone group. LLLT prevented hemorrhage, reduced inflammation severity, and preserved tendon morphology compared with the other groups. Conclusions: LLLT showed a significant superiority over commonly used anti-inflammatory pharmaceutical agents in acute collagenase-induced tendinitis. (AU)

• FAPESP's process: 11/18330-1 - The effect of low level laser therapy, topical antiinflammatory drug and exercise in the treatment of papain-induced knee osteoarthritis in rats
• Grantee: Rodrigo Alvaro Brandão Lopes Martins
• Support Opportunities: Regular Research Grants