title: How should the acetabular angle of Sharp be measured on a pelvic radiograph?
abstract: Four experienced orthopaedic surgeons measured the acetabular angle of Sharp (AA) in 66 hips by using two methods. In the classic method (AA-c), the lateral margin of the acetabular roof was used as the landmark. In the modified method (AA-m), the lateral margin of the sourcil (subchondral bony condensation in the acetabular roof) was used as the landmark. Mean AA-c and AA-m measurements were 44.8 degrees and 48.4 degrees, respectively. Mean intraobserver variations of AA-c and AA-m were 1.8 degrees and 2.1 degrees, respectively. Mean interobserver variations of AA-c and AA-m were 2.1 degrees and 2.6 degrees, respectively. Means obtained using AA-c of normal and defective acetabular roofs were similar, but the difference between AA-m means of different acetabular roof types was significant. The authors conclude that both AA-c and AA-m were reliable measurement methods, but clinical use of AA-m would probably produce better understanding of the radiographic hip anatomy in dysplastic hips.
authors.affiliation: Second Clinic of Orthopaedics and Traumatology, SSK Tepecik Hospital, Izmir, Turkey.
authors.forename: Haluk
authors.initials: H
authors.lastname: Agus
authors.forename: Ali
authors.initials: A
authors.lastname: Biçimoglu
authors.forename: Hakan
authors.initials: H
authors.lastname: Omeroglu
authors.forename: Yücel
authors.initials: Y
authors.lastname: Tümer
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging*; D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D006617:Hip Dislocation / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D015588:Observer Variation; D011859:Radiography