Legg-Perthes disease

Legg-Calvé-Perthes syndrome is a degenerative disease of the hip joint, where a loss of bone mass leads to some degree of collapse of the hip joint, that is, to deformity of the ball of the femur and the surface of the hip socket. The disease is typically found in young children and small dogs, and it can lead to osteoarthritis in adults.
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A hip disorder in children due to interruption of the blood supply to the head of the femur (the ball in the ball-and-socket hip joint). Also called Legg disease and Legg-Calve-Perthes disease.