Photobiomodulation Associated With Conservative Treatment for Achilles Tendon Rupture: A Double-Blind, Superiority, Randomized Controlled Trial

OBJECTIVE: To investigate the effects of photobiomodulation on Achilles tendon rupture (ATR) treated conservatively. DESIGN: Prospective, patient- and assessor-blinded, parallel, randomized controlled trial. SETTING: Patients with acute ATR treated conservatively. PARTICIPANTS: Thirty-four male individuals with acute unilateral ATR treated conservatively (N=34), equally divided in 2 groups: photobiomodulation group (PBMG) and sham group, with mean age of 45.5±9.47 and 48.7±8.38 years, respectively. INTERVENTION: All participants underwent through an immobilization period, followed by rehabilitation sessions (2 d/wk for 12 weeks) comprising strengthening, range of motion, and balance/weightbearing exercises. In PBMG, the tendon was irradiated with a photobiomodulation cluster (1 904 nm/50 mW infrared laser, 4 858 nm/50 mW infrared diodes, and 4 658 nm/40 mW red diodes; power density of 105 mW/cm(2) per cluster area) during the immobilization period (2 d/wk for 8 weeks) and the sham group received a simulation of the procedure with no irradiation. Outcomes were assessed at the removal of the immobilization 12 and 16 weeks after tendon rupture. MAIN OUTCOME MEASURES: Primary outcome was the Achilles Tendon Rupture Score. Secondary outcomes included Numerical Pain Rating Scale at rest and during effort, plantar flexor strength, and ankle range of motion. RESULTS: Both groups demonstrated an increase in the Achilles Tendon Rupture Score and improvements in range of motion, plantar flexor strength, and pain. There were no significant differences in outcomes between the 2 groups (P>.05) except in pain during walking, which was significantly lower in the PBMG in week 12 (P<.01, effect size=0.56) and week 16 (P<.01, effect size=0.55). CONCLUSION: Photobiomodulation associated with conservative treatment is not superior to conservative treatment alone for improving function in patients with acute ATR.