What is the cause and management of Legg-Calve-Perthes disease?

From the Guidelines

Legg-Calve-Perthes disease is a childhood hip disorder caused by temporary interruption of blood supply to the femoral head, leading to bone death (avascular necrosis), with the exact cause remaining unclear. The disease typically affects children between 4-10 years old, predominantly boys 1. Management of Legg-Calve-Perthes disease focuses on preserving hip joint structure and function while the femoral head naturally regenerates over 2-4 years.

Key Considerations

• The condition is characterized by temporary interruption of blood supply to the femoral head, resulting in avascular necrosis.
• It predominantly affects children between 4-10 years old, with boys being more commonly affected than girls.
• Treatment depends on the child's age and disease severity, with options ranging from observation and activity modification for younger children with mild cases, to containment therapy using braces or surgical interventions for more severe cases.

Management Approaches

• For younger children (under 6) with mild cases, observation and activity modification may be sufficient.
• Most children require containment therapy to keep the femoral head properly positioned in the acetabulum during healing, using either non-surgical methods (braces like the Petrie cast or Scottish Rite orthosis worn for 12-18 months) or surgical interventions (femoral or pelvic osteotomy) 1.
• Pain management includes NSAIDs like ibuprofen and physical therapy to maintain range of motion.
• Weight-bearing restrictions and avoiding high-impact activities are essential during treatment.

Disease Progression and Outcomes

• The disease's natural history involves bone resorption, fragmentation, reossification, and remodeling phases, with outcomes generally better in younger children.
• Long-term monitoring is necessary as some patients may develop early osteoarthritis in adulthood despite appropriate treatment 1.

From the Research

Cause of Legg-Calve-Perthes Disease

• The exact cause of Legg-Calve-Perthes disease (LCPD) is still poorly understood, with various hypotheses researched but none found to be decisive 2.
• Emerging evidence suggests that environmental risk factors, such as maternal smoking, low birth weight, and socioeconomic deprivation, may play a role in the development of LCPD 3.
• Genetic factors, including mutations in COL2A1 and polymorphisms in IL6, may also contribute to the disease, although twin studies do not support a major role for genetic factors 2, 3.
• Mechanical induced ischemia, leading to avascular necrosis of the femoral head, is another theory that has been proposed as a possible cause of LCPD 2.

Management of Legg-Calve-Perthes Disease

• Non-operative treatment is not effective in managing LCPD, and surgery is often required to prevent long-term damage to the hip joint 4.
• Femoral varus osteotomy and Salter's innominate osteotomy are two surgical procedures that have been shown to provide good outcomes in patients with LCPD 4.
• The use of bisphosphonates has been proposed as a potential treatment for LCPD, although the evidence is still limited and further research is needed to determine its effectiveness 5.
• The management of LCPD should be individualized, taking into account the age of the patient, the severity of the disease, and the presence of any underlying risk factors 4, 6.