the histological and biochemical changes on experimental osteoarthritis in rabbit knee

Osteoarthrosis (OA) is a common joint disease, characterized by degenerative changes in articular cartilage and reactive proliferation of bone and cartilage around the joint. The evaluation of the histological and biochemical changes were investigated on the articular cartilage of knee joint during development of osteoarthritis in rabbits following anterior cruciate ligament transsection (ACLT). A total of 12 New Zealand White (NZW) male rabbits with closed epiphyses underwent ACLT of knees and healthy control knees arthrotomy. The animals were killed at 9 weeks after surgery. The parameters tested were gross morphology, histology as well as urinary pyridinoline (Pyr) and creatinine. Morphological changes in osteoarthritic femoral condyles were seen on both, medial and lateral region, but markedly on medial condyle of the ACLT knee. The articular cartilage was characterised by a rough and hypertrophic appearance with severe erosions. The gross morphological examination of healthy control revealed no changes. Histological evidence for cartilage degeneration was observed in the ACLT knees. In OA femoral condyles the articular cartilage showed degenerative changes, including: rough surface, loss of superficial layer, erosion, fissures, irregular arrangement and form of chondrocytes. Biochemical determinations showed significantly higher concentrations of urinary Pyr in the OA rabbits compared to healthy rabbits during the whole period of the study (9 weeks), indicating a higher collagen degradation of cartilage and subchondral bone in the osteoarthritic animals.