A new methodology for the measurement of the Wiberg angle in infants under 3 months.

This article describes the measurement of the Wiberg center edge angle in infants under 3 months using sonographic images of their hips. In the literature review, there was no reference of the application of this angle in this particular age group. Thus, a methodology has been developed based upon the fact that, at this age, the acetabular roof constitutes a large portion of hyaline cartilage. In this way, it was concluded that it was not possible to apply the original Wiberg method since the center of the femoral head can be only estimated and not accurately determined in plain radiography. For this present study, 400 hips of 200 infants were analyzed. All these hips were classified as type 1a or 1b, according to Graf. The sonographic images were transferred to a Pentium computer through a video Spigot interface. The images were analyzed by software specially developed for this purpose. Since ultrasonography allows the exact recognition of the anatomical elements of the hip joint in young children, software provided the acetabular cartilaginous roof angle that corresponds to the center edge angle in adults. The authors believe that this method will be helpful in the early detection of morphological alterations in the hip joint.

Racial and geographic differences of Wiberg's angle from 400 ultrasonographic normal hips in Italian and Brazilian infants younger than 3 months old.

The Wiberg center edge angle (CEA) of 400 hip sonographies among 200 infants, 100 Italians and 100 Brazilians, aged from 15 days to 90 days, whose hip joints were considered normal, from the ultrasonographic point of view (1a and 1b) according to Graf's classification were measured. For the CEA measurements in the studied material, the authors used their own methodology developed for this purpose, which is based on basic geometric concepts and applied by one graphic computer program. In the studied material, the statistical analysis of the results obtained in the measurement of the CEA showed a better conformation of the acetabular roof complex in the Brazilian infants compared with the Italian.