Deformation analysis of in-vivo implant for total hip arthroplasty using multidetector-row CT images

In the field of orthopedic surgery, many types of implant have been used. Especially, revision total hip arthroplasty (THA) uses a metallic implant called support implant to reconstruct the damaged acetabulum. After the revision THA, the support implant might be deformed or be broken in serious cases by the strong load or by the other factors. However, there are few effective diagnosing methods for evaluating the 3-D deformation of the support implant in vivo. This study proposes a novel approach for finding the deformation of the support implant in vivo. The proposed method uses Multidetector-row CT images to take the 3-D shape of the support implant, and employs the combination of finite element method (FEM) and genetic algorithm (GA). The new combination gives us the new application of FEM. The proposed system was evaluated by computer-simulation experiment, and the effective of the system was demonstrated by applying it to the revision THA patient.