Legg Calve Perthes disease is a disorder of the epiphysis (growing part of bone) of the upper end of femur. It is characterized by the loss of blood supply in the upper femoral epiphysis. The epiphysis is necrosed (becomes dead). It then gets absorbed and replaced. This leads to deformation of the femoral head.
It is commonly seen in children between the age of 4 to 12 years. Three to four times more common in boys as compared to girls. It is rare in Negroes, Indians and Polynesians.
Early symptoms include pain on walking. Limping is seen. Pain is located over he effected hip. On examination tenderness may be present. Movements of the hip are restricted. In the later stages of Perthes disease there is absence of pain or pain is felt during prolonged and strenuous activity. In adulthood osteoarthritis of the hip may develop.
Diagnosis is by x rays. Findings present on x rays depend on the stage of the disease. Here we shall see the x ray findings along with the natural history of the disease.
Stage of synovitis - In this stage fluid in the joint is increased. This is due to irritation of the synovial membrane. X rays may show slight increase in joint space.
Stage of Necrosis - In this stage part or whole of the ossification centre becomes dead and weak. Due to this it cannot withstand the normal forces acting across the hip joint. These forces cause the round head to flatten. This flattening can be seen on x rays. Flattening extends from the outer side of the femoral head to the inner side.
Stage of Regeneration - In this stage the dead bone is absorbed and replaced with new bone. If only a small part of the epiphysis was dead. Then it gets reformed and the round head appears. If the whole epiphysis had become necrotic then the replacement with new bone shows as clear areas between the dead bone. This gives an appearance of fragmentation on the x rays.
Stage of Healing - In this stage the dead bone is completely absorbed and replaced with new bone. This new bone is weak, therefore it gets deformed. This deformation can produce various defects such as ovoid, cup shaped, mushroom shaped, or an enlarged head. The head may protrude beyond the acetabulum.
The blue arrow in this x ray points to the flattened head of femur.
The red arrow in this x ray points to a hip showing fragmentation.
Classification of Perthes disease according to Catterall
Group 1 - Less than half the epiphysis is involved. Involvement is limited to the anterior portion only. No collapse no sequestrum formation occurs.
Group 2 - Half or less than half of the epiphysis is involved. Involvement is limited to anterior portion only. Collapse sequestrum formation is seen.
Group 3 - More than half the epiphysis is involved, leaving only a small part of the posterior portion, with a large sequestrum.
Group 4 - The entire epiphysis is involved.
Other investigations that can help in the diagnosis and classification include
2 Bone scan
Treatment of Perthes disease depends on the stage of the disease. Goal of treatment is to minimise the deformation of the femoral head. This can only be done by
1. Reducing the deforming forces acting across the joint
2. Providing a proper template for remodeling of the femoral head.
Treatment methods include the following
1. Recumbent treatment with traction applied to the affected limb in abduction and internal rotation.
2. Use of various braces such as Scottish Rite, Newington or Toronto brace.
3. Surgery. (rarely required in the active period of the disease)
Good prognosis can be expected regardless of the treatment modality and even with no treatment
- if the age of onset is less than 6 years.
- Catterall group 1 and 2.
Bad prognosis is seen in patients who are
- above 7 years of age at the time of onset.
- Catterall group 3 and 4.
These patients require more aggressive treatment.
In spite of all treatment methods used in the active stage of the disease some patients still develop deformity in the femoral head. Depending on the type of the deformity some re-constructive surgery may be required.
I hope the information provided on perthes disease was helpful. If you have any query you can ask me at the contact me page.
This page was last updated on 12th October 2010.
Other causes of hip pain...
Avascular Necrosis of Hip
Congenital Dislocation of Hip
Go back to Hip Pain from Perthes Disease