Revision total hip arthroplasty.: Analysis of the predictive value of a radiographic classification system for assessment of bone stock loss

Aim: The aim of this study was to evaluate the predictive value of a radiographic classification system concerning implant and bone graft in revision total hip arthroplasty. This classification is used to assess bone stock loss prior to surgery, thus hypothetically enabling an adequate choice of the implant and bone graft required. Method: 33 consecutive patients with the diagnosis of aseptic failure of total hip arthroplasty were included in the study. The investigation was performed using the classification system according to Saleh et al. The predictive value was analyzed by comparing the radiographically based recommendation concerning implant and bone graft and the intraoperative procedure according to a blinded observer technique. The Spearman coefficient of correlation (r(s)) was used to establish levels of agreement among multiple ordinal variables. Results: Analysis of correlation between preoperative radiological estimations and intraoperative conclusions concerning implant and bone graft revealed coefficients of correlation (r(s)) of 0.53 (p < 0.01) for the acetabular and of 0.63 (p < 0.01) for the femoral classification. Conclusion: Our results indicate that the Saleh classification does not provide sufficient information for preoperative assessment of the revision implant and bone graft required concerning the acetabular side, whereas planning of the operative procedure regarding the femoral implant seems to be possible. These ambivalent findings should be taken into account prior to revision total hip arthroplasty.