Orthopedics

Legg-Calve-Perthes Disease

Background

Legg-Calve-Perthes disease, (LCPD) is idiopathic avascular necrosis (AVN), or osteonecrosis of the capital femoral epiphysis. It is a disease characterized by ischemic necrosis, collapse and subsequent remodeling of the femoral head. LCPD is typically characterized as presenting with a "painless limp" but can present with anterior thigh pain, limp, or limitation of motion at the hip. Legg-Calve-Perthes disease occurs most often in Caucasian boys between the ages of 4 and 12 years of age, with the mean age of presentation being 7 years of age. The male: female ration of LCPD is about 5:1. Legg-Calve-Perthes disease is found to be bilateral in 10 to 15% of cases. There is no associated fever, increased WBC count, or increased ESR with the disease. The origin of Legg-Calve-Perthes disease is currently unknown, but it is thought to be caused by multiple vascular occlusive episodes that involve the femoral head, leading to AVN. LCPD has also been associated with thrombophilia, protein C and S deficiency, and hypofibrinolysis.

Common Symptoms:

  1. painless limp
  2. mild or intermittent pain in anterior thigh
  3. painful limp
  4. antalgic gait
  5. mild restriction of motion (on abduction and internal rotation)
  6. thigh atrophy
  7. mild shortness of stature

Diagnosis:

The diagnosis of Legg-Calve-Perthes disease is essentially a radiological one. AP and frog-leg lateral films of the hips should be taken and evaluated carefully, as LCPD is easily missed. Radiologic films can show:

  1. Early disease can present with devascularization around the capital femoral epiphysis
  2. Mild disease can present with fragmentation and collapse of the CFE
  3. Moderate disease shows reossification
  4. Resolving disease can show remodeling.

Radiographic image demonstrating Legg-Calve-Perthes disease
http://upload.wikimedia.org/wikipedia/commons/f/f6/LeggCalvePerthes2.jpg).

Complications:

Osteoarthritis, or degenerative arthritis in adulthood are the most common complications resulting from Legg-Calve-Perthes disease. The risk for degenerative arthritis in adulthood correlates with the restoration of the sphericity of the femoral head at the resolution of disease. Older children with residual femoral head deformity are at the greatest risk of developing degenerative arthritis in adulthood.

Treatment:

Legg-Calves-Perthes disease is essentially a local, self-resolving disorder. However, all suspected cases of LCPD deserve an immediate orthopedic referral. Preventing further femoral head deformity and secondary degenerative arthritis are the indications for treatment. Containment of the femoral head within the acetabulum is the aim of treatment. For children under the age of 6, expectant observation is recommended, with frequent orthopedic and radiological evaluation. Temporary treatment with bed rest or abduction stretching exercises may be recommended. Non-surgical or surgical containment of the femoral head within the acetabulum is indicated if the age of the child is > 6 years, and if the lateral CFE is involved in the disease. Non-surgical casting confining the femoral head within the acetabulum can be achieved with abduction casts. This non-surgical method usually takes up to 18 months, or until there is radiographic evidence of subchondral reossification. Surgical treatment consists of a pelvic or femoral osteotomy to contain the femoral head. Studies have shown that surgical containment results in improved prognosis for LCPD.

References:

  1. Adkins. Hip Pain in Athletes. American Family Physician. 2000; 61(7): 2109-2118.
  2. Leet, A. Evaluation of the Acutely Limping Child. American Family Physician. 2000; 61(4): 1011-1018.
  3. Hubbard, A. Imaging of Pediatric Hip Disorders. Radiologic Clinics of North America. 2001; 39(4): 721-732.
  4. Kim, M. The Limping Child. Clinical Pediatric Emergency Medicine. 2002; 3(2): 129-137.
  5. Behrman. Nelson's Textbook of Pediatrics, 16th Ed. W.B. Saunders, 2000; 2080-2081.
  6. Canale. Campbell's Operational Orthopedics, 9th ed. Mosby, 1998; 866-868.
  7. Scherl S. Common Lower Extremity Problems in Children Pediatrics in Review. February 2004