A perspective on the study of Moseley et al: questioning the value of arthroscopic knee surgery for osteoarthritis.

Arthroscopy for degenerative conditions of the knee is among the most commonly employed orthopedic procedures, but its effectiveness (like the effectiveness of many surgical operations) has never been proven in prospective trials. Moreover, the precise mechanism by which arthroscopy improves the course of degenerative conditions of the knee has not been established conclusively. Moseley et al performed a double-blinded, randomized, placebo-controlled trial to compare the effectiveness of arthroscopic lavage and arthroscopic debridement vs a sham procedure. Data regarding pain and function were obtained at multiple time points over a 2-year period. The authors found that all three treatment groups fared equally: each reported subjective symptomatic relief, but no objective improvement in function was noted in any of the groups. These data suggest that the benefits of arthroscopy for the treatment of osteoarthritis of the knee is to provide subjective pain relief, and that the means by which arthroscopy provides this benefit is via a placebo effect.