To evaluate arthroscopic findings as a potential measurement of severity and outcome of chondropathy.
110 patients with knee osteoarthritis (OA) were included in a cross sectional study and 41 of them in a one year longitudinal study. The evaluation of OA performed once in the cross sectional study and twice (at entry and after one year) in the longitudinal study, included clinical, radiological and arthroscopic variables evaluating disease activity and severity. Arthroscopy was performed. under local anesthesia in an outpatient procedure using a small arthroscope. Chondropathy was evaluated by the overall assessment of the investigator by visual analog scale and the Société Française d'Arthroscopie (SFA) scoring and grading systems, which represent a composite index taking into account depth, size, and localization of the articular cartilage lesions.
The intrinsic validity of the arthroscopic variables was suggested by highly significant correlation (R2 = 80-85%) between the overall assessment of the investor and the SFA systems. There was also highly significant correlation (p < 0.01) between the arthroscopic and radiological variables. Intraobserver reliability of the arthroscopic quantification of chondropathy was better than interobserver reliability. In the cross sectional study, severity of chondropathy correlated with both age and body mass index. In the longitudinal study there was statistically significant worsening in the severity of chondropathy and statistically significant correlation between the changes in the severity of chondropathy and changes in functional impairment.
We conclude that arthroscopy might be considered a relevant measurement of OA outcome for research purposes.