Legg-Calvé-Perthes disease is a health condition that involves avascular necrosis of the proximal femoral head. In common language, this refers to damage induced by reduced blood flow to the ball of the thighbone in the hip. This can lead to the death of the bone. As a result, the bone may collapse and become flattened. Over time, the blood supply usually returns and builds up the bone cells again. New bone may eventually replace the old bone over a period of several years.
The disease usually affects young boys from 4 to 10 years of age, but the exact cause of the condition is unknown. It is a rare condition that affects approximately 4 in 100,000 children.
Signs and Symptoms
The first sign of Legg-Calvé-Perthes disease is usually limping. The child does not usually complain of pain, although some intermittent pain is occasionally reported.
Symptoms may include:
- Hip stiffness
- Limited movement and range of motion
- Thigh, groin or knee pain
- Shortening of one leg, leading to unequal leg length
- Loss of thigh muscle
The condition is usually unilateral, which is what causes the unevenness of the gait and posture, and limping.
The diagnosis of Legg-Calvé-Perthes disease will usually begin with a consultation about the reported symptoms and medical history. A physical examination helps to detect signs such as changes in muscle mass, movement and range of motion.
To confirm the diagnosis, a hip or pelvis x-ray may be ordered to detect characteristic changes in the bone. Magnetic resonance imaging (MRI) may also be required in some cases, particularly if a more detailed image is needed.
It is important for the diagnosis to be made as soon as possible when indicative symptoms present. This is because children who are diagnosed at an earlier age (before the age of 6) typically have more positive treatment outcomes and eventually regain a normal hip joint. Children who are diagnosed after the age of 6 are more likely to have a deformed hip joint and have a greater risk for arthritis later in life.
The aim of treatment in Legg-Calvé-Perthes disease is to contain the ball of the thighbone inside the hipbone socket. This is important because it helps to maintain the range of motion in the hip.
There are several lifestyle changes that can help to reduce the impact of the condition on the individual. For example, reducing participation in high-impact activities that place a large amount of weight and strain on the leg can be beneficial.
Physical therapy is important to increase the strength of the leg and hip muscles. Additionally, some patients may benefit from a cast or brace fitted to help contain the thighbone in the hip socket. If the limp is particularly bad, using crutches or a walker to improve mobility may be beneficial.
If severe pain is posing a problem, bed rest can help to improve symptoms. Even a short period of rest can help improve the pain significantly. Some medications may also be beneficial to reduce pain and inflammation. Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen may often be effective in relieving hip joint stiffness.
Finally, a surgical procedure may be required when other treatments have not been successful. There are various types of procedures that may be utilized, according to the severity of the disease and the shape of the bone. These may include lengthening of the groin muscle, osteotomy or reshaping of the pelvis.