The informative value of radionative diagnostics in cases of patellar chondropathy

The present study of 64 patients analyzes the diagnosticability of patellar chondropathy on the basis of X-ray native images. The results were confirmed intraoperatively or arthroscopically. We evaluated images of both knees in a.p. and lateral projection and walking images with 30, 60, and 900 of joint bending. In all cases of chondropathy of third degree, radiomorphologic changes could be delineated; in stage I this was possible in 66% of the cases. The summarizing assessment of structural irregularities as discontinued contours of the subchondral osseous lamella, spot-like or diffuse demineralisation, osteophyteous peripheral serration, disintegration in the insertion area of the quadriceps tendo, soft-tissue swelling and hemarthrosis is significant for establishing the diagnosis. Whereas there is a causal relationship between defective axial positions of the patella or particularly posttraumatic defect and the development of a chrondropathy, we could not detect in the investigated patient-group a significantly higher incidence of chondropathy in cases of dysplasia of the patella or of the femoral condyles. A simple scheme - applicable in arthroscopy and radiology - is introduced: it shall help to record chondromalacious regions and considers the most frequently affected areas. (orig.)