Perthes disease is a rare disorder whose most serious consequences can compromise the mobility of the hip. Sometimes, surgical treatment is the best option. It occurs in children aged 4 to 12 years old when the head of the femur stops receiving blood. When there is no adequate blood supply, the bone goes through necrosis, a fancy word for tissue death, causing osseous fragility. As a result, pain and lameness in the child comes about. If Perthes disease progresses without treatment, the head of the femur regenerates again (the deteriorating bone gets absorbed by the body as it dies) with two possible results. On one hand, it could recover a rounded shape, or, the bone ends up deformed.
Evolution of Perthes Disease
Phase 1: in the initial phase, there is a lack of blood flow in the femoral head and a consequent death of the bone. There is inflammation, stiffness and pain (but not always) in the joints of the hip and when viewing x-rays, the head of the femur looks irregular.
Phase 2: this phase is known as the fragmentation phase, where the dead cells are reabsorbed and replaced by healthy new cells. It begins to regenerate and to acquire a rounded shape. This phase can last between 12 to 18 months.
Phase 3: also called re-ossification phase, the head of the femur continues to recover an adequate shape and can take between 24 to 36 months.
Phase 4: in the healing phase, normal bone cells replace those that went through fragmentation.
The causes of Perthes disease are unknown, although some researches point to a vascular origin. In addition, it is known that the probability of boys to suffer it is four times higher than girls. In most cases, only one hip is affected. Generally, the child suffering from Perthes disease complains of hip pain but it is also possible that the pain occurs in the thigh and knee. The pain intensifies physical activity is performed and can disappear when resting. Most of the time, the child will have pronounced limpness.
The diagnosis of Perthes disease begins with a physical examination and a complete study of the child’s medical history. To confirm the diagnosis the doctor or specialist may suggest the following procedures: X-rays, magnetic resonance imaging (MRI) and a bone scan.
The treatment of Perthes disease varies depending on the severity of each case. Its main objective is to preserve the rounded shape of the head of the femur during the illness, while also controlling the pain suffered by the patient. In the initial phase, the treatment is based on analgesics. Among the main recommendations are bed rest, restriction of physical activity, avoiding the use of the affected limb and rehabilitation therapy.
During advanced stages, the objective is to reshape the head of the femur so that the joint retains its ability to move. To achieve this, the doctor or specialist may suggest different methods. A more traditional treatment consists of using orthopedic splints to limit certain movements. This way, the head of the femur will be kept in a position that allows the bone to be properly accommodated. On the other hand, you can opt for surgical treatment to allow the head of the femur to be positioned correctly. It is the orthopedic doctor who must decide which treatment is the most appropriate. You can also opt for physiotherapy to strengthen the muscles of the hip to stimulate movement.