Cartilage necrosis due to pin penetration: experimental studies in rabbits.

An animal model was used to evaluate the role of pin penetration into the hip joint as the cause of chondrolysis. The gross and microscopic studies, as well as the biochemical studies, showed changes indicating cartilage destruction. These changes were more severe when the pins remained in the joint. Immunologic studies showed some type of immunological interaction. The immunologic response may be initiated by release of cartilage byproducts. The initial insult of the slip may cause release of cartilage byproducts from the exposed growth plate within the joint, and is compounded by penetration of the pin in the hip joint.