MR imaging as a supplement to traditional decision-making in the treatment of LCP disease.

Background: Heretofore, the general concept in treating Legg-Calve-Perthes (LCP) disease has been containment of the diseased femoral head into the acetabulum. However, surgery or bracing for containment of a deformed femoral head without accurate information on its dynamic relationship with the hip may aggravate hip congruity and lead to impingement between the femoral head and the acetabulum. We used magnetic resonance imaging on an outpatient clinic basis to evaluate the relationship between the deformed femoral head and the acetabulum in moderate-to-severe LCP disease, and applied these findings to management.