Navigation Reduces the Learning Curve in Resurfacing Total Hip Arthroplasty

Hip resurfacing is a novel technique with a substantial learning curve resulting in poor outcomes for many patients. We asked whether navigation would influence this learning curve and accuracy of implantation. Twenty medical students earning their degree in surgical technology participated in a randomized trial. We provided instruction about the surgical technique, including the use of conventional instrumentation, the use of a computed tomography-based planner for hip resurfacing, and a navigation system. The 20 students were then split into three groups undertaking these tasks in three different orders. Synthetic femurs replicated normal, osteoarthritis, slipped capital femoral epiphysis, and coxa valga. The mean error using the conventional method to insert a guidewire was 23°; using the computed tomography plan method it was 22°; and using navigation was 7°. Students produced similar accuracy, even in their first attempt, on difficult anatomy when provided navigation. Motivated students rapidly achieved an expert level of accuracy when provided with navigation. Learning a conventional method first did not improve performance, even in difficult cases. Our data suggest navigation may play an important role in reducing the learning curve in hip resurfacing arthroplasty and other tasks in arthroplasty in which a high degree of accuracy is clinically important.