What is Perthes disease?

Perthes disease is a painful condition of the hip that affects children. It involves a problem with the blood supply to the top of the thighbone (femur).

The hip is known as a 'ball and socket’ joint. The top of the femur (femoral head) is ball-shaped, and fits into a socket in the pelvis.

In Perthes disease, the femoral head becomes soft and goes out of shape. This causes pain and a limp.

Perthes disease usually affects children aged from 3 to 11 years.

It takes time, but most children recover fully.

What are the symptoms of Perthes disease?

Symptoms of Perthes disease include:

• pain in the hip, knee, thigh or groin
• a slight limp that becomes worse over time
• limited movement
• uneven leg length — the affected leg may become shorter

Children with Perthes disease are otherwise healthy.

What causes Perthes disease?

It is not clear what causes Perthes disease, or why the blood supply to the femoral head is reduced.

Perthes disease usually affects one hip, although it can happen in both hips. It sometimes runs in families. It is more common in males than in females.

When should I see my doctor?

If your child is limping, has leg pain or limited movement in their leg, they should be seen by their doctor.

How is Perthes disease diagnosed?

If your child has pain in the hip, thigh or knee, your doctor may suggest an x-ray to check for a diagnosis of Perthes disease. If the x-ray doesn’t provide an answer, other more sensitive tests can include:

• MRI scan
• ultrasound
• bone scan

How is Perthes disease treated?

In most cases, the bone will repair itself over 2 to 5 years, if it doesn’t become too damaged.

Treatment is aimed at avoiding damage to the hip. This might include:

• avoiding activities with a high impact on the hip, such as running
• rest, which may include use of a wheelchair or crutches
• a splint or a plaster
• special exercises

In rare cases, your child may need surgery.

If your child has Perthes diseases, a specialist doctor will monitor their progress and guide their treatment.

Complications of Perthes disease

For some children, the femoral head does not recover properly and remains deformed. These children can experience ongoing hip stiffness and early arthritis of the hip.

Resources and support

For more information about the symptoms, diagnosis and treatment of Perthes disease, visit the Sydney Children’s Hospitals Network website.

Call healthdirect on 1800 022 222 at any time to speak to a registered nurse (known as NURSE-ON-CALL in Victoria) for more information and advice.