The role of inherited thrombotic disorders in the etiology of Legg-Calve-Perthes disease

Inherited thrombophilia has been suggested as a cause of Legg-Calve-Perthes disease in up to 75% of patients. This prevalence seems high compared to t he prevalence of inherited thrombophilia in other thrombotic disorders (ave rage, 30%). Therefore, we investigated 44 patients with Legg-Calve-Perthes disease for antithrombin-III, protein-C, and protein-S deficiency and activ ated protein C (APC) resistance. Three (6.8%) of our patients were positive for APC resistance, and one patient (2.2%) showed deficiency of protein-C activity. Our results suggest that inherited thrombophilia is not associate d with avascular necrosis of the femoral head (Legg-Calve-Perthes disease).