Catterall versus Herring classification in Perthes' disease.

It is the purpose of this study to compare the prognostic value of the Herring classification (lateral pillar) with that of the Catterall classification. The material is constituted by 45 patients affected with Perthes' disease and reviewed an average of 24 years after onset. At follow-up the hips were divided into three classes based on joint congruency as suggested by Stulberg. The Catterall classification demonstrated overall a better predictive value for the Herring system. Instead, the most satisfactory reproducibility seems to be that of Herring: 80% as compared to 42% for the Catterall classification.