title: A novel computer-based method for measuring the acetabular angle on hip radiographs.
abstract: OBJECTIVE
  The aim of this study was to propose a new computer based method for measuring acetabular angles on hip radiographs and to assess its practicality, sensitivity and reliability for acetabular angle measurement.
  
  
  METHODS
  A total of 314 acetabulum were assessed on 157 pelvic X-ray images. Acetabular angles were measured with both the conventional method (Method 1) and our proposed method (Method 2). All the Acetabular Index (AI) angle, Acetabular Angle (AA) and Acetabular Center (ACM) angle were measured with both methods.
  
  
  RESULTS
  The mean AI angle for Method 1 is 11.02° ± 2.7° and the mean AI angle for Method 2 is 10.08° ± 1.88°, the mean AA angle for Method 1 is 39.5° ± 5.3° and the mean AA angle for Method 2 is 39.36° ± 4.68°, the mean ACM angle for Method 1 is 50.5° ± 6.01° and the mean ACM angle for Method 2 is 55.42° ± 12.43°.
  
  
  CONCLUSIONS
  Our novel automated method appear to be reliable and practical for acetabular angle measurement on hip radiographs.
  
  
  METHODS
  Level III, Diagnostic study.
authors.affiliation: Department of Electrical and Electronics Engineering, Baskent University, Ankara, Turkey.
authors.forename: Seda
authors.initials: S
authors.lastname: Sahin
authors.affiliation: Department of Electrical and Electronics Engineering, Baskent University, Ankara, Turkey.
authors.forename: Emin
authors.initials: E
authors.lastname: Akata
authors.affiliation: Department of Orthopaedic and Traumatology, Baskent University Hospital, Ankara, Turkey. Electronic address: drorcunsahin@gmail.com.
authors.forename: Orcun
authors.initials: O
authors.lastname: Sahin
authors.affiliation: Department of Orthopaedic and Traumatology, Baskent University Hospital, Ankara, Turkey.
authors.forename: Cengiz
authors.initials: C
authors.lastname: Tuncay
authors.affiliation: Department of Orthopaedic and Traumatology, Gulhane Military Medical Academy Hospital, Ankara, Turkey.
authors.forename: Hüseyin
authors.initials: H
authors.lastname: Özkan
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging*; D003936:Diagnosis, Computer-Assisted; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography / Q000379:methods*; D012016:Reference Values; D015203:Reproducibility of Results; D012189:Retrospective Studies
keywords: Acetabular angle; Computer-based measurement; Hip radiograph; Obturator foramen; Pelvic X-ray; Pelvic angle