Perthes Disease is an uncommon condition that affects young children and their hip development. The blood supply that feeds the head of the femur (the ball in the ball and socket of the hip) is interrupted. This allows the bone to die back, and become misshapen. However, it is a self limiting condition and some cases will fully resolve without intervention.

Symptoms of Perthes Disease
The condition usually starts around the age of 9, but it has a broad window of onset. It affects boys much more than girls. The earliest symptoms are often hip or groin pain (illustrated above) or a limp. These symptoms are often slow to come on and slow to progress. Over time, limited hip movement may become noticeable, along with muscle wasting in the thigh.
Osteopaths need to be aware of the condition as its symptoms can be subtle. Rheumatological conditions or fractures can present similarly, so we need to be able to rule them out or know when to refer on for more investigation. Response to treatment will be limited as long as the blood flow is interrupted, although we may be able to help with temporary symptomatic relief and managing compensatory patterns. Compensation may be more stark for patients who are undergoing treatment with a brace or using crutches. Usually once the disease has run its course, the affected leg will be slightly shorter than the other. This can have a knock-on effect to the lower back, where this asymmetry is often absorbed. We can help the body to adapt to this change to limit the secondary effects of it.
Stretching exercises are recommended as the condition progresses, which is an area we can help with.
Disease Process
As the blood flow is limited, some bony tissue in the head of the femur dies. This can cause the joint surface to become rough, or flattened in places. Over time this malformed bone is reabsorbed, and the body remodels it when the blood supply returns. The resulting joint surface could be as perfect as if the disease had never affected it, or it can remain misshapen and continue to cause problems. Early onset osteoarthritis is more likely in patients who had Perthes Disease as a child, especially those whose symptoms started after the age of 10.
Risk Factors for Perthes Disease
Causes for the disease have not been fully identified, and generally it is considered to be an idiopathic condition. Each case is likely due to a combination of factors. These may include:
low birth weight
trauma
exposure to tobacco smoke
a positive family history of the disorder
The area in which the blood flow is interrupted is usually the growth plate. Sometimes an X-Ray or MRI will show what looks like a fracture in the growth plate, which may be a factor in the onset. However this is not present in all cases.
Osteochondrosis
Perthes Disease is not unique in the way it develops. The same process can occur at other joints, such as the knee in Osgood Schlatter Disease. The process is known as osteochondrosis, which refers to an issue with the growth plate within a bone, often for unknown reasons.