title: [X-ray morphological study of the hip joints in children of pre-school age].
abstract: Age characteristics of the ossification of hip joints were studied at the stage of their most active formation in children aged under 6 years using radiographical archive documents (1898 hip arthrograms in direct projection). According to our observations, the ossification of the femoral caput in modern children begins at the age of 3 to 5 months (88.6%--1158 cases), which is earlier than previously reported (from 6 to 12 months). In addition, we have studied in detail all the variants of the ossification of the femoral caput, such as: the fragmented center of ossification (3.6%--68 cases), various sizes of ossification centers on the right and on the left sides (11.4%--216 cases), an eccentric position of the center of ossification in the cartilaginous caput (2.1%--40 cases). Sex differences in the formation of acetabulum roof were described for the first time: the acetabulum angle in girls proved to be 3-4 degrees larger than that in boys (91.9%--1746 cases). Thus, our studies made it possible not only to update the information on the age osteology of this part of the skeleton, but also to define the variants of the individual features of ossification as well as to detect the signs of sex determination in the formation of hip joints in pre-school children.
authors.forename: L G
authors.initials: LG
authors.lastname: Konstantinova
authors.forename: V G
authors.initials: VG
authors.lastname: Mazur
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging* / Q000254:growth & development; D006801:Humans; D007223:Infant; D008297:Male; D010012:Osteogenesis / Q000502:physiology*; D011859:Radiography; D014965:X-Rays