Legg-Calve-Perthes (LEG-kahl-VAY-PER-theez) disease is a childhood condition that affects the hip, where the thighbone (femur) and pelvis meet in a ball-and-socket joint.
Legg-Calve-Perthes disease occurs when blood supply is temporarily interrupted to the ball part (femoral head) of the hip joint. Without sufficient blood flow, the bone begins to die — so it breaks more easily and heals poorly.
To keep the ball part of the joint as round as possible, doctors may use a variety of treatments to keep it snug in the socket portion of the joint. The socket acts as a mold for the fractured femoral head as it heals.