Experimental post-contusive osteoarthritis of the knee: quantitative microscopic study of the patella and the femoral condyles.

A contusive procedure has been developed for the induction of a predictable and reproducible degenerative joint disease in knees of rabbits. Significant degeneration was observed in patella, condyles, and trochlea. These lesions included fibrillation, ulceration and erosion, clones of chondrocytes, and osteophyte formation. The incidence and distribution of lesions with time following contusion were also investigated. Lesions were observed as early as 1 day post-contusion and increased in number and severity. A global scoring system has been devised to permit comparisons of lesion incidence and severity, specially to test drug efficacy in this model of osteoarthritis.