title: Prediction of long-term polyethylene wear in total hip arthroplasty, based on early wear measurements made using digital image analysis.
abstract: The capability to reliably predict long-term in vivo wear of polyethylene would be of great value for the early identification of problematic total hip designs. Formal quantitative estimates of long-term polyethylene wear were made from a series of 197 patients who had a total hip arthroplasty and who were followed for a minimum of 10 years; the estimates were based on the wear that was apparent radiographically at nominally 2 years after the operation. A newly developed digital image-analysis edge-detection procedure was applied to 1,237 archived follow-up radiographs. The edge-detection measurements were analyzed with a robust regression random-coefficients statistical formulation developed especially to address the distributions of wear rate observed across this population over time. Formal regression equations were reported, which can be used to estimate late-wear depth for a patient radiographed at a 2-year follow-up visit. Series wide, the correlation between predicted and observed wear depths was 0.73 at 4 years, with a correlation decline of approximately 0.03 per additional year.
authors.affiliation: Department of Orthopaedic Surgery, University of Iowa, Iowa City 52242, USA.
authors.forename: D R
authors.initials: DR
authors.lastname: Pedersen
authors.forename: T D
authors.initials: TD
authors.lastname: Brown
authors.forename: S L
authors.initials: SL
authors.lastname: Hillis
authors.forename: J J
authors.initials: JJ
authors.lastname: Callaghan
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip; D015331:Cohort Studies; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D008297:Male; D008422:Materials Testing; D011095:Polyethylenes; D011237:Predictive Value of Tests; D011859:Radiography
chemical_list: D011095:Polyethylenes