Frequently Asked Questions for Legg-Perthes Disease

Is Perthes curable?

It is not curable because we don't know the cause. However, it is a self-healing disease, meaning the body is able to heal the bone in the femoral head that is affected. The healing process and the duration of the disease seem to vary from patient to patient. The clinical outcome also varies, depending on the age of the patient, the extent of femoral head involvement and the lateral pillar height (see illustration on Legg-Perthes web page).

Will my child ever be able to run again or be involved in sports?

In our experience, most patients are able to return to running and sports once the femoral head is into the healing phase.

How long does it take for Perthes to “run its course?”

The duration of the disease seems to vary from patient to patient, and there is no sure way to tell from the onset how quickly or slowly the healing will take place. On average, the course of the disease can run from three to five years.

Why do they call it a “disease?” Is it contagious?

It is a disease because it adversely affects the cells in the femoral head and affects hip function and development. It is not contagious, and it is generally not passed on from one generation to another in most cases.

Is it genetic?

Perthes disease usually does not run in families. Only 10 to 15 percent of patients have another family member with this disease.

What is the time frame of Perthes?

Perthes disease can be divided into four stages, which are called the initial stage, resorptive or fragmentational stage, reossification stage and healed stage. The duration of the disease can vary from one patient to another. In general, it may take three to five years for a patient to go from the initial stage to the healed stage of the disease.

How does the hip grow back?

Although the blood supply to a part or all of the femoral head is disrupted and stops the femoral head from growing, healing will occur over time since tissue around the affected part of the femoral head is alive and is able to respond to the abnormal change. In many patients, especially those with early onset of the disease (before age 6), normal growth is restored. In older patients, restoration of normal growth of the hip is not as predictable.

What symptoms or signs should I look for?

At the early stage of the disease, your child may complain of groin, thigh or knee pain during or after physical activity. Some children may complain of pain at rest. Your child may also have restricted hip movement and a mild limp.

Should I expect a lot of complaints of pain?

Amount of pain experienced by a child with Perthes disease seems to vary from patient to patient. Some patients complain of activity-related pain or night pain only.

What are the long-term effects of Perthes?

The long-term effects of Perthes disease are related to the residual deformity of the femoral head and the mismatch between the deformed femoral head and the acetabulum. One long-term study found that if the femoral head is moderately deformed (Stulberg classification III), about 58 percent of the patients had X-ray signs of degenerative arthritis by their late 40s and 50s. In this study, those children with late-onset disease (age 8 or older) had a greater risk of developing arthritis. A study at TSRHC by Dr. Herring and co-authors found that with early-onset disease 80 percent of the patients had a good outcome.

Will my child need a hip replacement?

If so, when? Hip replacement is not a surgery for children. Only if a patient develops painful degenerative arthritis later in adulthood is the surgery warranted. Even with a deformed femoral head, most patients can perform daily activities and sports activities once the hip has healed.

Should my child have a hyperbaric oxygen treatment?

To our knowledge, there is no evidence to support that hyperbaric oxygen treatment improves the outcome of Perthes disease.

What activities are safe or beneficial for my child?

We would recommend a consultation with your physician to determine the activities that are safe and beneficial because the answer would depend on the stage of the disease, your child's symptoms, hip joint stiffness and your child's age.

What is the purpose of a tenotomy?

Tenotomy is sometimes performed when there is a restriction of hip abduction (i.e. ability to spread the leg outward). The muscles that are involved with bringing legs together (hip adductors) can become tightened or contracted and are lengthened to improve hip abduction.