Results of the present prospective study confirm the findings of the previous retrospective study and suggest that Ilizarov joint distraction is a promising treatment for severe ankle OA, at least delaying the need for a joint fusion. Considering the high prevalence of OA and the lack of a remedy for this disorder, Ilizarov joint distraction as a treatment for OA may have great medical, social and economic impact.

Results suggest that the promising clinical results of Ilizarov joint distraction in patients with OA are accompanied by changes in cartilage metabolism. A change in proteoglycan turnover, indicating normalization of overall chondrocyte function, might in the long term, with normal joint use, lead to actual repair of cartilage.

The aim of this study was to investigate the relationship between location and size of osteophytes and cartilage loss in an instability-induced experimental model for osteoarthritis. Osteoarthritis was induced in murine knee joints by injection of highly purified bacterial collagenase, causing joint instability. The size of the osteophytes and the cartilage loss were measured at different locations in the joint using image analysis on histological sections of total kees. Cartilage damage did not occur without osteophytes. Osteophytes were located on both medial and lateral sides, independent of the location of cartilage damage, but the size of the osteophytes was related to the amount of cartilage damage on the corresponding side. Cartilage loss on the lateral tibial plateau correlated well with the size of lateral osteophytes, in particular with the osteophyte at the margin of the lateral tibial plateau. Cartilage loss on the medial tibial plateau appeared to have a good correlation with the size of medial osteophytes, which was most pronounced for the osteophyte on the medial margin of the tibial plateau. This side-specific correlation between cartilage damage and osteophyte formation suggests compartmentalization of the osteoarthritic process.

No abstract

The aim of this study was to evaluate a method for the quantification of cartilage erosions and osteophyte sizes in a murine model of osteoarthritis (OA). Mice in which OA was induced in the knee joint by intra-articular injection of bacterial collagenase were used. With an interactive image analysis system, the areas occupied by osteophytes and the areas of erosions of the articular cartilage were measured on histological sections by two independent observers at two time points. Measurements of osteophyte areas and cartilage loss at the tibial plateau showed good reproducibility, whereas measurement of cartilage loss at the femoral condyles was less reproducible. Measurement of three frontal total knee joint sections from the middle part of the joint provided a reliable measure for cartilage damage and osteophyte size in the total joint. A cumulative score was developed, composed of both cartilage loss and osteophyte size, which can be used as a general measure for OA of the knee joint. The presented method of quantitative scoring makes it possible to perform correlation studies and to investigate the effect of therapeutic interventions on the osteoarthritis process.