The impact of femoral bone quality on cementless total hip pre-operative templating.

Abstract

Accurate templating is an integral part of pre-operative planning for total hip arthroplasty (THA). Templating of cementless implant accuracy has been average. The aim of this study was to assess the impact of Dorr femoral classification on the accuracy of pre-operative digital templating. This was a retrospective study of cementless THA pre-operative planning using one implant design. A total of 210 primary THA were reviewed. A total of 102 cementless THAs matched the exclusion and inclusion criteria, using one implant combination, were analyzed by an orthopaedic resident and a fellowship trained arthroplasty surgeon. Each x-ray was evaluated and assigned a femoral Dorr classification. Accuracy of templating was determined by comparing the templated size with the actual implant size both for the femoral and acetabular components. Out of the 102 cases, exact templating size was achieved in 35.3% for the acetabulum, 25.5% for the femur, and only in 9.8% for both components. Reasonable templating, ± one of the actual size, was achieved in 78.4% for the acetabulum, 74.5% for the femur, and 60.8% for both components. Use of Dorr femoral type classification did not result in better templating accuracy. Pre-operative hip cementless templating using digital x-rays with double marker method do not improve accuracy compared to other methods available for templating. Accounting for bone quality using the Dorr femoral classification did not improve accuracy.