title: A new technique for radiographic measurement of acetabular cup orientation.
abstract: Accurate radiographic measurement of acetabular cup orientation is required in order to assess susceptibility to impingement, dislocation, and edge loading wear. In this study, the accuracy and precision of a new radiographic cup orientation measurement system were assessed and compared to those of two commercially available systems. Two types of resurfacing hip prostheses and an uncemented prosthesis were assessed. Radiographic images of each prosthesis were created with the cup set at different, known angles of version and inclination in a measurement jig. The new system was the most accurate and precise and could repeatedly measure version and inclination to within a fraction of a degree. In addition it has a facility to distinguish cup retroversion from anteversion on anteroposterior radiographs.
authors.affiliation: Wrightington Hospital, UK.
authors.forename: Brian
authors.initials: B
authors.lastname: Derbyshire
authors.affiliation: Lancaster University, UK.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Diggle
authors.affiliation: Norfolk and Norwich University Hospital, UK.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Ingham
authors.affiliation: Norfolk and Norwich University Hospital, UK.
authors.forename: Rory
authors.initials: R
authors.lastname: Macnair
authors.affiliation: Norfolk and Norwich University Hospital, UK.
authors.forename: James
authors.initials: J
authors.lastname: Wimhurst
authors.affiliation: Wrightington Hospital, UK.
authors.forename: Henry Wynn
authors.initials: HW
authors.lastname: Jones
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging* / Q000601:surgery; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D001837:Body Weights and Measures; D006621:Hip Joint / Q000000981:diagnostic imaging* / Q000601:surgery; D006622:Hip Prosthesis; D006801:Humans; D011859:Radiography
keywords: acetabular cup; cup inclination; cup orientation; cup version; radiographic measurement