الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 32 |  |  |
| | | from | 32 | | |
Abstract
Perthes’ disease has been studied extensively for almost the last 100 years and still, the aetiology is not clear and the outcome is unpredictable. It predominately affects young boys around 4-8 years of age. Late-onset after the age of 10 years usually carries a poor prognosis due to the short time left until skeletal maturity and the remodelling phase is inadequate to accommodate the deformed head into the acetabulum. In severe cases especially of late-onset flattening of the femoral head with joint incongruity can lead to “hinged abduction” and premature osteoarthritis of the hip.
In Perthes’ disease, containment of the head in the acetabulum and an acceptable range of motion are the aims of management in the belief that the femoral head is biologically plastic. However, there is still no consensus as to when to perform a surgical containment. It is at present generally accepted that, if less than half the head is necrotic and the lateral pillar is intact, no treatment is necessary, as it would not alter the natural course of the condition. If more than half of the head is necrotic and the lateral pillar is collapsed, surgical attempt to improve the natural course of the disease is indicated
Both surgery, on the femoral or pelvic sides, have their advocates. The rationale is to reduce the laterally sublaxated portion of the femoral head to better distribute joint forces. If the femoral head is in the acetabulum and there is a good range of motion, results should be good provided there is sufficient growth remaining to allow some remodeling. Girls have a worse prognosis ; this could be related to their earlier skeletal maturity with less time remaining for remodeling.
In the clinical practice many patients presented in a later stage of the disease when there is already hinge abduction or poor range of motion. Containment procedures are contraindicated in these patients, which in turn makes the outcome of the disease even worse. These patients were treated in a two-stage procedure. Stage one involves arthrodiastasis or articulated joint distraction with an external fixator in all patients. The goal of arthrodiastasis is to prevent further femoral head flattening while improving the mobility of the involved hip. Once the range of motion of the hip joint improves and the joint distracts sufficiently for the head to be able to relocate into the acetabulum, containment of the head by a varus osteotomy of the femur is performed as a second stage procedure.