Lead author Dr. Wiroon Laupattarakasem, of Khon Kaen University in Thailand, led a systematic review of studies on the surgical procedure arthroscopic debridement, which involves trimming damaged cartilage and bone spurs.

"There may be certain types of pathology or certain levels of disease severity for which arthroscopic debridement can be more effective," Laupattarakasem said in a statement. "It should by no means be regarded as inappropriate for every knee. At this time, clinicians must make decisions regarding arthroscopic debridement on a case-by-case basis. ""

The review, published in The Cochrane Library, was based on three randomized controlled studies with 271 patients. The studies compared arthroscopic debridement with lavage -- which is flushing and suctioning debris from the joint -- and sham surgery.

The three treatments produce similar results in pain and physical function after two years, although debridement could cause greater discomfort in the first few weeks after surgery.

The reviewers said more studies are needed.