Perthes disease is a childhood condition of the hip that occurs when the blood supply to the rounded head of the femur is temporarily disrupted. The rounded head of the femur fits into the hip socket and helps make up the hip joint. If the bone does not have an adequate blood supply, it begins to die and over time will break down and lose its round shape. As time passes, the body will eventually restore blood supply to the bone and the bone will begin to heal. New bone cells will gradually replace the dead bone, but this process may take several years. If the ball of the femur is no longer round after it has healed, it can cause pain and stiffness.
Causes and Risk Factors
The underlying cause of the temporary disruption of blood flow to the femoral head is still unknown. The disease commonly affects children between the ages of 4 and 8, and is more common in boys than girls.
One of the earliest signs of Perthes disease is a change in the way your child walks or runs. This often is most apparent during sports or other activities; the child may have a limp, limited motion, or develop a different running style. Other common symptoms include:
- Pain or stiffness in the hip, groin, thigh, or knee
- Pain that worsens with activity and gets better with rest
- Muscle spasms around the hip
The long-term prognosis for children with Perthes disease is generally good. The goal of treatment is to relieve pain and other symptoms, protect the hip joint, and restore normal function of the hip joint. If left untreated, Perthes disease can lead to complications in adulthood, such as early onset arthritis. There are several treatment options for Perthes disease, and your orthopedic surgeon will consider several factors including age, degree of damage, and stage of the disease.
Nonsurgical treatment options for Perthes disease include:
- Observation through periodical x-rays
- Anti-inflammatory medications
- Limiting activity and avoiding high impact activities
- Physical therapy
- Casting and bracing
Your doctor may recommend surgery to re-establish proper alignment of the hip joint if the damage is severe. Generally speaking, most children return to their daily activities without major limitation after 18 months to two years of treatment.