Relationship between osteophyte and arthroscopic findings in osteoarthritis of ankle

Category: Ankle Introduction/Purpose: Mortise view weight-bearing radiograph is widely used for the diagnosis of osteoarthritis of ankle. Thickness of the articular cartilage cannot be accurately evaluated in the evaluation of joint space from weight-bearing radiograph, because lateral tibiotalar joint space is maintained in valgus type osteoarthritis in some cases. There are few reports on the relation between osteophyte and the articular cartilage injury. We considered that it might be possible to estimate the cartilage injury more accurately by examining osteophytes. The purpose of this study is to analyze the relationship between the location and grade of osteophytes in weight-bearing radiograph and cartilage injury in arthroscopic findings was analyzed. Methods: Twenty-one anklets of 21 patients consisted of 10 males and 10 females, with mean age of 61.4 years (31-79 years), who underwent arthroscopic surgery for osteoarthritis in our department were included. Weight-bearing radiograph were taken before surgery. Location and grade of osteophytes were evaluated using Ankle and Hindfoot Radiographic Osteoarthritis Scoring reported by Kraus et al. Arthroscopic findings were evaluated with International Cartilage Repair Society (ICRS) Grade at a total of 20 sites (9 areas of tibia and talar in tibiotalar joint, medial malleolus and lateral malleolus). The correlation between radiographic findings and arthroscopic findings were analyzed. Results: In Mortise view, strong correlations were found between lateral tibial osteophyte grade and ICRS grade of the center (talus R = 0.69, tibia R = 0.76), the central lateral (tibia R = 0.79), the posterior center (talus R = 0.72, tibia R = 0.74) and the posterior lateral of the tibiotalar joint (talus R = 0.63, tibia R = 0.76). There are moderate correlations between distal fibular osteophyte grade and ICRS grade of the medial inner (tibia R = 0.74) and the posterior medial of the tibiotalar joint (talus R = 0.61, tibia = 0.63). In lateral view, there are moderate correlations between posterior talar osteophyte grade and ICRS grade at the center of the tibiotalar joint (talus R = 0.61, tibia R = 0.60). Conclusion: From this study, there was a strong correlation between location and grade osteophyte and the articular cartilage injury. Osteoarthritis progression is caused by degeneration of the cartilage because of the joint instability, and osteophytes were formed by traction force or impaction. This study showed that local cartilage injury is thought to be related to osteophytes. By evaluating the location and size of osteophytes, the articular cartilage injury might be predicted accurately before arthroscopic surgery.