Abstract
Each in vivo wear measurement method for total hip arthroplasty (THA) has strengths and weaknesses. The authors have developed a new manual wear measurement method (PowerPoint [PP] method) and validated that the PP method was found to have better repeatability, reproducibility and pick up differences in the radiographs than the previously established manual wear measurement methods. The primary aim of this study was to evaluate the reliability of the PP method by retrieval study. 17 retrieved polyethylene (PE) liners (16 patients) were enrolled in this study. The wear volumes of retrieved PE liners from clinical radiographs were calculated by the PP and Dorr and Wan method and they were compared with the wear volume of retrieved PE liners calculated by the triangulation three-dimensional (3D) laser scan. Spearman correlation coefficients results between PP method and 3D laser scan revealed excellent correlations (0.89 to 0.93). The Intraclass Correlation Coefficients values of the PP method showed excellent correlations (0.95 to 1.00). We suggest that the PP method will be a viable new technique for measuring wear of THA and a supplement method when computerized methods are not available.
