Abstract
This paper describes an automated 3D acetabular cup planning method in total hip arthroplasty. A number of past preoperative plans prepared by experienced surgeons and used for actual computer navigated surgery are utilized to model surgeon’s expertise of surgical planning. We construct “pelvis-cup merged statistical shape model (PC-SSM)” by applying principal component analysis to mergers of cup shape and pelvis shape. The cup shape has size, position, and orientation planned by experienced surgeon. The PC-SSM is fitted to the patient pelvis to automatically generate the preoperative plan. According to the performance evaluation, cup size errors between the proposed method and the experienced surgeon’s plans were within one size in 34 cases out of 38 cases. Since the PC-SSM is automatically constructed from training datasets while the previous method based on a manual definition of criteria, we consider the proposed method may be useful for quantitative evaluation of surgeons’ trends for cup planning as well as for automated planning. As a remaining problem, the performance in severely diseased pelvis is needed to be improved.
