It is a well designed trial on several levels. It documented the knees radiographically at baseline and follow-up. However, added Klippel, the trial falls short in other ways. For example, biomarkers would help to prove whether or not glucosamine influences cartilage damage or cartilage repair. Other experts assert that the study is seriously undermined by flawed radiographic data.
Any results are subject to questions.
Felson's comments were based to some extent on new research by rheumatologist and anatomist J. Chris Buckland-Wright, MD, of Guy's Hospital in London. He asserted that the apparent improvement in joint space width observed by the researchers did not necessarily reflect anatomically healthier joints, but merely less painful joints. This is a problem inherent in the use of AP views, he explained. On entering the trial, patients in both groups were in pain and equally unable to fully extend their knees, Buckland-Wright pointed out. At the end of the trial, the patients taking glucosamine experienced pain relief.