A new methodology for the measurement of the Wiberg angle in infants under3 months

This article describes the measurement of the Wiberg center edge angle in i nfants under 3 months using sonographic images of their hips. In the litera ture review, there was no reference of the application of this angle in thi s particular age group. Thus, a methodology has been developed based upon t he 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 possibl e to apply the original Wiberg method since the center of the femoral head can be only estimated and not accurately determined in plain radiography. F or this present study, 400 hips of 200 infants were analyzed. All these hip s were classified as type 1a or 1b, according to Graf. The sonographic imag es 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 eleme nts of the hip joint in young children, software provided the acetabular ca rtilaginous roof angle that corresponds to the center edge angle in adults. The authors believe that this method will be helpful in the early detectio n of morphological alterations in the hip joint.