Legg-Calve-Perthes disease (a condition described by Legg, Calve, Perthes and Waldenstrom in the early 20th century) strikes children and can leave them crippled. Rates vary from 6/100,000 to 15/100,000 depending on the population studied though it appears to be of higher frequency among anglo-saxons. It is currently believed that osteochondritis dissicans is a local phenomenon(…)