Ultrasonographic evaluation of Legg-Calve-Perthes disease based on sonoanatomic criteria and the application of new measuring techniques.

This study attempts an ultrasonographic classification of Legg-Calve-Perthes disease according to sonoanatomic and sonometric criteria. Four stages, similar to standard radiological staging, could reproducibly be found in 29 patients with unilateral disease. The stages could be significantly differentiated according to descriptive sonoanatomic criteria and partially newly introduced sonographic measurements, including epiphysis-metaphysis-index and acetabulum-epiphysis-distance. Sonographic evaluation of Perthes hips is a simple and standardised procedure, which can serve to stage and monitor the course of the disease and hence reduce the amount of X-ray exposure and treatment costs.