The Accuracy and Ability of Preoperative Templating to Restore Femoral Offset in Calcar-Guided Short-Stem Total Hip Prosthesis through Direct Anterior Approach

Abstract

The aim of this study was to assess the applicability and ability of preoperative templating to restore femoral offset and hip length with a calcar-guided short-stem implant design in total hip arthroplasty through the direct anterior approach. Preoperative measurements were performed of femoral offset, hip length, and stem size and compared with the perioperative placed prosthesis in 100 patients undergoing primary total hip replacement through direct anterior approach. Additionally, the pre- and postoperative femoral offset and hip length were compared to evaluate the ability to restore the offset and hip length with this kind of femoral short stem. With an acceptance of 1 size difference pre- and postoperatively, a 94% accuracy of predicting the size of the calcar-guided short stem was achieved with templating. Femoral offset was within means of 5 mm in 82.2% of the patients. Postoperative hip length was within 6 mm in 90% of the patients compared with the preoperative length.The use of preoperative templating for total hip arthroplasty with calcar-guided short-stem implants was proven to be a useful tool to predict the definite implanted size of the femoral prosthesis. Our results show that this new stem design does not significantly differ from previous reported outcomes with other stem designs and is competent to restore the femoral offset and hip length within clinical acceptable range. Level of evidence Level 3 retrospective case study.