Spontaneous cartilage degeneration in guinea pigs

Abstract

Spontaneous degeneration of the knee joint cartilage in male Hartley guinea pigs was studied by light microscopy in animals aged 3–18 months. Unilateral focal degeneration, characterized by chondrocyte death and proteoglycan loss with surface fibrillation, was observed on the medial tibial plateau in 2 of 5 guinea pigs that were 3 months old. The incidence and severity of the lesions increased with age, and by 12–18 months of age, all animals had moderate‐to‐severe degeneration of the medial tibial plateau, femoral condyle, and meniscus. Lesions were not present on the lateral aspect of the knee joint in any of the animals.