Pathophysiology and new strategies for the treatment of Legg-Calvé-Perthes disease

▶ Legg-Calvé-Perthes disease is a juvenile form of idiopathic osteonecrosis of the femoral head that can lead to permanent femoral head deformity and premature osteoarthritis. ▶ According to two recent multicenter, prospective cohort studies, current nonoperative and operative treatments have modest success rates of producing a good outcome with a spherical femoral head in older children with Legg- Calvé-Perthes disease. ▶ Experimental studies have revealed that the immature femoral head ismechanically weakened following ischemic necrosis. ▶ Increased bone resorption and delayed new bone formation, in combination with continued mechanical loading of the hip, contribute to the pathogenesis of the femoral head deformity. ▶ Biological treatment strategies to improve the healing process by decreasing bone resorption and stimulating bone formation appear promising in nonhuman preclinical studies.