Histological and Histomorphometrical Evaluation of Tibial Plateau in Cats With Osteoarthritis

Feline osteoarthritis (OA) is a joint disease that causes cartilage degeneration and bone changes, impairing load transmission and joint function in ageing cats. This study aimed to assess histologic and histomorphometric changes in the tibial plateau of cats with naturally occurring stifle OA and to determine the relationship between cartilage damage and bone changes. Osteochondral tissues from 12 OA and 10 normal cats were examined with H&E and Safranin O staining. Histology showed higher total articular damage scores in OA cats (p<0.05), with cartilage changes ranging from fibrillation to complete loss. Bone histomorphometry revealed increased trabecular bone volume fraction (BV/TV) and subchondral bone plate thickness (Subcho. BP.Th) in OA cats, though trabecular thickness did not differ (p>0.05). However, damage to the articular cartilage showed no relationship with changes in the underlying subchondral bone. These findings highlight the importance of evaluating both cartilage and subchondral bone in OA