Legg-Calve-Perthes disease is when the ball of the thighbone in the hip doesn’t get enough blood, causing the bone to die.
Coxa plana; Perthes disease
Causes, incidence, and risk factors
Legg-Calve-Perthes disease usually occurs in boys 4 – 10 years old. There are many theories about the cause of this disease, but little is actually known.
Without enough blood to the area, the bone dies. The ball of the hip will collapse and become flat. Usually only one hip is affected, although it can occur on both sides.
The blood supply returns over several months, bringing in new bone cells. The new cells gradually replace the dead bone over 2 – 3 years.
The first symptom is often limping, which is usually painless. Sometimes there may be mild pain that comes and goes.
Other symptoms may include:
- Hip stiffness that restricts movement in the hip
- Knee pain
- Limited range of motion
- Persistent thigh or groin pain
- Shortening of the leg, or legs of unequal length
- Wasting of muscles in the upper thigh
Signs and tests
During a physical examination, the health care provider will look for a loss in hip motion and a typical limp. A hip x-ray or pelvis x-ray may show signs of Legg-Calve-Perthes disease. An MRI scan may be needed.
The goal of treatment is to keep the ball of the thigh bone inside the socket. Your health care provider may call this “containment.” The key to doing this is to make sure the hip has good range of motion. In some cases, bracing is used to help with containment.
Physical therapy and anti-inflammatory medicine (such as ibuprofen) can relieve stiffness in the hip joint. If your hip is painful or the limp gets worse, limiting the amount of weight placed on the leg or restricting activities such as running may help. Nighttime traction devices may also be used.
Health care providers no longer recommend several months of bed rest, although a short period of bed rest may help those with severe pain.
Surgery may be needed if other treatments fail. Surgery ranges from lengthening a groin muscle to major hip surgery to reshape the pelvis, called an osteotomy. The type of surgery depends on the severity of the problem and the shape of the ball of the hip joint.
It is important to have regular follow-up with your doctor and an orthopedic specialist.
The outlook depends on the child’s age and the severity of the disease. In general, the younger the child is when the disease starts, the better the outcome.
Children younger than 6 years old who receive treatment are more likely to end up with a normal hip joint. Children older than age 6 are more likely to end up with a deformed hip joint, despite treatment, and may later develop arthritis.
Osteoarthritis may develop later in life. Early recognition and proper treatment of Legg-Calve-Perthes disease may minimize this complication.
Calling your health care provider
Call for an appointment with your health care provider if a child develops any symptoms of this disorder.
McQuillen KK. Musculoskeletal disorders. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 7th ed. Philadelphia, Pa: Mosby Elsevier; 2009:chap 174.
Sankar WN, Horn BD, Wells L, Dormans JP. Legg-Calve-Perthes disease. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 670.3.