Perthes disease (also known as Legg-Calve-Perthes disease, or Calve Perthes disease, or avascular necrosis) is a childhood disorder which affects the head of the femur (the ball of the ball and socket joint of the hip). It typically occurs in children who are between 4 and 10 years old. It is five times more common in boys than in girls, however, it is more likely to cause extensive damage to the bone in girls. In 10% to 15% of all cases, both hips are affected.
In Perthes disease the blood supply to the growth plate of the bone at the end of the femur (called the epiphysis) becomes inadequate. As a result, the bone softens and breaks down (a process called necrosis). Over time, the blood supply to the head of the femur returns and the bone begins to grow back.
The cause of Perthes disease is not known. Some recent studies indicate that there may be a genetic link to the development of Perthes, but more research needs to be conducted.
One of the earliest signs of Perthes is a change in the way your child walks and runs. This is often most apparent during sports activities. Signs and symptoms of Legg-Calve-Perthes disease include:
Legg-Calve-Perthes disease usually involves just one hip. Both hips are affected in some children, usually at different times.
Depending upon your child’s activity level, symptoms may come and go over a period of weeks.
Imaging studies like X rays and MRI scans
Treatment for Perthes focuses on helping the bone grow back into a more rounded shape that still fits into the socket of the hip joint. This will help the hip joint move normally and prevent hip problems in adulthood.
The long-term prognosis for children with Perthes is good in most cases. After 18 months to 2 years of treatment, most children return to daily activities without major limitations.