The aim of the study is to evaluate the prognostic value of Herring’s classification for treatment planning of Perthes Disease and predicting the final outcome of the disease.

We analysed 45 patients treated in our department in the period of 1992 – 2005. The analysis consisted of determining the lateral pillar collapse in fragmentation stage and the containment of the femoral head in the residual stage. We did retrospective analysis of the x-rays in fragmentation stage and classified the patients according to Herring’s classification. Group A included 10 patients, group B – 20 patients and group C included 15 patients. We used Hayman – Herndon Acetabulum – Head Index (AHI) to analyse the x- rays in the residual stage. The statistical analysis of the results included the analysis of the differences between the lateral pillar collapse among the groups and the differences between affected hip and the contralateral control hip. Correlation between the degree of lateral pillar collapse and the AHI in the residual stage was also analyzed. Correlation between the age of onset of the disease and AHI was determined for each group, too.

The results show significant differences between the lateral pillar collapse in Herring groups, and among the affected and control hips. Differences of AHI values were also significant between the groups. Correlation between the AHI and lateral pillar collapse for each group shows moderate connection just as the one between AHI and age.

Herring’s classification is reliable in classifying patients with Perthes disease. It enables good prediction of the natural course of the disease and thus influences the treatment decision-making