Legg-Calvé-Perthes disease is destruction of the growth plate of the thighbone.
Legg-Calvé-Perthes disease develops most commonly among boys between the ages of 5 and 10. The disease usually affects only one leg. About 10% of children have a relative who has the disease. It is caused by a poor blood supply to the upper growth plate of the thighbone. The reason for the poor blood supply is not known.
Legg-Calvé-Perthes disease can cause severe hip damage without causing significant symptoms at first. The severe damage may, however, lead to permanent arthritis of the hip. The first symptom is often pain in the hip joint and trouble walking (gait). Pain begins gradually and progresses slowly. The pain tends to worsen when moving the hip or walking. Some children complain of pain in the knee. A limp can develop, sometimes before the child has much pain. Eventually, joint movement becomes limited, and the thigh muscles may become wasted (atrophied) from lack of use.
The diagnosis is confirmed by x-rays. A magnetic resonance imaging (MRI) scan is done if x-rays are normal. Later x-rays may show changes around the growth plate, such as a fracture or destruction of the bone. Rarely, doctors do a bone scan.
Doctors take x-rays of the skeleton if the disorder runs in the child's family or both of the child's legs are affected. These x-rays are taken to rule out hereditary disorders of the skeleton. Blood tests are done to rule out other disorders. Doctors try to determine whether the symptoms result from injury.
Young children and children who have less damage when they are diagnosed have the best outcome.
Treatment includes prolonged immobilization of the hip. Sometimes the partial immobilization provided by bed rest is sufficient. However, sometimes nearly total immobilization for 12 to 18 months is necessary, requiring traction, slings, plaster casts, or splints. Such treatments keep the legs rotated outward. Physical therapy is used to keep the muscles from contracting and wasting away. If a child is over age 6 and has moderate or severe bone destruction, surgery may be helpful. Regardless of how it is treated, Legg-Calvé-Perthes disease usually takes at least 2 to 3 years to heal. Treatment with bisphosphonates (drugs that help increase bone density) has been effective, but more studies are needed.