Perthes' disease Dr Rob Hicks Dr Trisha Macnair Perthes' disease causes deformity of the hip joint in children, owing to an interruption in the blood supply to the head of the thigh bone.

In this article

What's the cause? Who's affected?

How's it diagnosed? What's the treatment?

Advice and support

Perthes' disease (also known as Legg-Calve-Perthes' disease) affects the top of the femur (thigh bone) where it meets the hip bone. The blood supply to the growth plate of the bone (epiphysis) becomes inadequate. As a result, the bone softens and breaks down - a process called necrosis.

This happens gradually over several weeks. Then, as the blood supply recovers, the bone reforms and hardens. This takes 18 to 36 months and may lead to a deformed shape, with flattening of the ball-shaped head of the femur that normally fits into the round socket of the hip joint.

Recent research has suggested Perthes' may be linked to a subtle problem with blood clotting.

What are the symptoms?

The first sign of Perthes' disease is usually hip or groin pain, or a limp. Knee pain can also be an early symptom.

The pain persists and there may be wasting of the muscles in the upper thigh, shortening of the leg and stiffness of the hip, which can restrict movement and cause problems with walking.

When Perthes' disease has been present for a long time, the affected leg may be shorter and thinner than the unaffected one.

Perthes' most commonly affects children between the ages of four and eight, but younger children and teenagers can also develop the condition.

It affects around one in 20,000 children and is up to five times more common in boys. It's also more common among Caucasians.

In ten to 20 per cent of cases, both hips are affected.

If a child with hip pain has limited hip movement, an x-ray will be taken to check for Perthes'. In the early stages of the disease this may be normal, so the x-ray must be repeated if symptoms persist. Bone scans, MRI scans and other tests may also be used.

The aim of treatment is to reduce hip pain and stiffness, prevent deformity of the head of the thigh bone, and achieve and maintain a full range of movement in the hip joint.

Treatment depends on the severity of the condition. In mild cases, where less than half the head of the femur is affected, bed rest and traction may be all that are needed.

In more severe cases, the femur may have to be splinted in position using a plaster cast or calipers. Occasionally, surgery is required.

Most children recover well with minimal long-term problems, especially if they're under six and the disease is mild. But in older children where more than half the head of the femur is affected, there's an increased risk of deformity and arthritis later in life.

Perthes' Association
Tel: 01483 306637
Email: help@perthes.org.uk
Website: www.perthes.org.uk

This article was last medically reviewed by Dr Orlena Kerek in March 2009