Far-Infrared Radiation to Improve Clinical Outcomes after Arthroscopic Rotator Cuff Repair: A Prospective Randomized Comparative Clinical Study

BACKGROUND: The efficacy of far-infrared radiation (FIR) after rotator cuff repair has not been demonstrated yet. The aim of this study was to evaluate the effects of postoperatively applied FIR with regard to early pain, range of motion (ROM), and tendon-to-bone healing after arthroscopic rotator cuff repair. METHODS: A total of 64 consecutive patients who underwent arthroscopic rotator cuff repair with small- to medium-sized tears were enrolled in this prospective comparative study and randomly divided into an FIR group (n = 31) and a control group (n = 33). In the FIR group, FIR using a radiator device (Aladdin-H) was applied for 30 minutes per session twice daily from the first postoperative day. This application lasted for 10 weeks during the postoperative period. Clinical outcomes were assessed using a visual analog scale for pain (pVAS) at 5 weeks and ROM at 3 and 6 months postoperatively. Functional scores were evaluated at 6 months postoperatively. Healing of the repaired rotator cuff was also evaluated using ultrasonography at 3 months and magnetic resonance imaging at 6 months postoperatively. RESULTS: In both groups, clinical and functional outcomes were improved up to 6 months compared with preoperative values. At 5 weeks and 3 months postoperatively, the average pVAS was significantly lower in the FIR group than in the control group (1.7 ± 1.0 vs. 2.8 ± 1.4; p = 0.002 at 5 weeks, 2.4 ± 1.3 vs. 3.2 ± 1.8; p = 0.041 at 3 months). However, there was no significant difference in ROM, functional score, or healing rate between two groups at each follow-up time point. CONCLUSIONS: The application of FIR after arthroscopic rotator cuff repair could be a safe and effective procedure to decrease postoperative pain, especially in the early postoperative period. This effective application of FIR can be considered to facilitate painless rehabilitation in the postoperative period after arthroscopic rotator cuff repair.