Preoperative photobiomodulation versus nonsteroidal anti-inflammatory drugs for pain and early functional recovery after total knee arthroplasty: a randomized controlled trial

Background Nonsteroidal anti-inflammatory drugs (NSAIDs) are a cornerstone of multimodal analgesia after total knee arthroplasty (TKA), but gastrointestinal, renal, cardiovascular, and bleeding risks may limit their perioperative use in some older adults. This study evaluated preoperative photobiomodulation therapy (PBMT) delivered with a stationary 810 nm semiconductor laser as a non-pharmacological pre-emptive analgesic strategy compared with celecoxib. Methods In this prospective, double-blind, double-dummy randomized controlled trial, 80 patients undergoing primary unilateral TKA were randomized 1:1 to preoperative PBMT (n = 40) or oral celecoxib (n = 40). The primary outcome was resting visual analogue scale (VAS) pain at 24 h after surgery. The non-inferiority margin was 1.0 VAS point and the assumed standard deviation for sample-size calculation was 1.5 points. Other pain time points, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), lower-limb swelling, early joint function, perioperative blood loss, and complications were also assessed. Results At 24 h, resting VAS pain was 3.9 ± 1.1 with PBMT and 3.7 ± 1.0 with celecoxib (PBMT minus celecoxib mean difference, 0.20 points; 95% CI, −0.27–0.67); the upper confidence limit was below the 1.0-point margin. The 48-h WOMAC scores were 42.4 ± 5.8 and 41.8 ± 6.2, respectively (P = 0.655). PBMT was associated with smaller increases in thigh circumference on postoperative days 3 and 7, less hidden blood loss, and fewer reports of gastrointestinal discomfort. Conclusion Preoperative 810 nm semiconductor-laser PBMT met the stated non-inferiority criterion for 24-h resting pain compared with celecoxib and was associated with favorable swelling, blood-loss, and gastrointestinal outcomes.