The effect of complementary therapies on post-operative pain control in ambulatory knee surgery: a systematic review

Ambulatory knee surgery is a common procedure with over 100,000 knee arthroscopies performed in the U.K. in 2010-2011. Pain after surgery can decrease patient satisfaction, delay discharge, and decrease cost effectiveness. Multi-modal therapies, including complementary therapies, to improve pain control after surgery have been recommended. However, a comprehensive review of the literature regarding the use of complementary therapies to enhance pain control after ambulatory knee surgery is lacking, and this article aims to address this deficit. CINHAL, EMBASE, MEDLINE, AMED and CENTRAL databases were searched. Only Randomised Controlled Trials were included. All eligible papers were quality assessed using the Jadad system, and data was extracted using piloted forms. Two independent reviewers performed each stage of the review. Full details of the study methodology can be found on Prospero, a systematic review register. Five studies satisfied our eligibility criteria: three reporting on acupuncture, one on homeopathy, and one on acupoints. Acupoint pressure was the only study that demonstrated reduced pain compared with placebo. This study was the least methodologically robust. Arnica, although demonstrating a significant reduction in swelling, did not affect post-operative pain. Acupuncture did not affect post-operative pain; however, a reduction in ibuprofen use was demonstrated in two studies. Before recommending complementary therapy for routine use in ambulatory knee surgery, further work is required. Two areas of future research likely to bear fruit are demonstrating robust evidence for the effect of acupoint pressure on post-operative pain, and quantifying the positive effect of homeopathic arnica on post-operative swelling.