title: Assessment of reproducibility and accuracy in templating hybrid total hip arthroplasty using digital radiographs.
abstract: In 20 patients undergoing hybrid total hip arthroplasty, the reproducibility and accuracy of templating using digital radiographs were assessed. Digital images were manipulated using either a ten-pence coin as a marker to scale for magnification, or two digital-line methods using computer software. On-screen images were templated with standard acetate templates and compared with templating performed on hard-copy digital prints. The digital-line methods were the least reliable and accuracy of sizing compared with the inserted prostheses varied between -1.6% and +10.2%. The hard-copy radiographs showed better reproducibility than the ten-pence coin method, but were less accurate with 3.7% undersizing. The ten-pence coin method was the most accurate, with no significant differences for offset or acetabulum, and undersizing of only 0.9%. On-screen templating of digital radiographs with standard acetate templates is accurate and reproducible if a radiopaque marker such as a ten-pence coin is included when the original radiograph is taken.
authors.affiliation: Department of Orthopaedics, The Norfolk and Norwich University Hospital NHS Trust, Colney Lane, Norwich, Norfolk NR4 7UZ, UK. Mjoddy9@aol.com
authors.forename: M J
authors.initials: MJ
authors.lastname: Oddy
authors.forename: M J
authors.initials: MJ
authors.lastname: Jones
authors.forename: C J
authors.initials: CJ
authors.lastname: Pendegrass
authors.forename: J R
authors.initials: JR
authors.lastname: Pilling
authors.forename: J A
authors.initials: JA
authors.lastname: Wimhurst
mesh_terms: D000077:Acetabulum / Q000601:surgery; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D005269:Femur / Q000601:surgery; D006621:Hip Joint / Q000000981:diagnostic imaging* / Q000601:surgery; D006622:Hip Prosthesis; D006801:Humans; D015588:Observer Variation; D010388:Pelvis / Q000000981:diagnostic imaging; D017755:Prosthesis Fitting; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D015203:Reproducibility of Results