What is Legg-Calvé-Perthes disease?

Legg-Calvé-Perthes disease (LCPD) is a condition in which the blood supply to a bone in the hip joint is disrupted. The hip joint is a ball and socket joint; it's the "ball" part of the long bone in the leg that's affected, at the point where it fits into the "socket" of the hipbone. (In some cases both hips may be involved.) No one knows what causes this problem, but over time the lack of blood can weaken the bone and make it more likely to break or become otherwise damaged. Fortunately, the blood supply usually returns to the area on its own and the bone heals, usually after about 18 to 36 months. Most children have no long-term disability.

LCPD is four times more common in boys than in girls, and usually affects children between the ages of 4 and 9. It is also more common in children who are shorter than average and have relatively immature bones for their age.

What are the symptoms?

This condition will cause your child to limp. He may also be complaining of pain in the hip, groin, or front of the thigh — or the limp may be painless and he won't complain at all. These symptoms usually come on gradually, rather than appearing suddenly as they would with an ordinary joint injury. If you notice that your child has been limping for more than a few days, call the doctor.

How is it evaluated and treated?

If your pediatrician suspects that your child has this condition, she'll do a physical exam and take X-rays of the joint. Once she's confirmed the diagnosis, she'll likely refer your child to an orthopedic specialist (a bone doctor) who will determine what kind of treatment will be appropriate based on your child's age and the extent of the damage to the bone. (While the bone will eventually heal on its own, the doctor may recommend treatment to try to prevent permanent deformity of the bone or arthritis.) Some children require only close follow-up and observation. Some will have to limit their activities; some will need to wear a brace or a cast until the bone heals; those with severe cases will need surgery to stabilize the bone or correct any deformity. The younger the child is, the less likely he is to need treatment or have damage to the joint. You can also give your child ibuprofen or acetaminophen for the pain.