Study on repositioning of comminuted fractured bones for computer-aided preoperative planning

The objective of this study is to provide a virtual simulation of bone fracture reduction system for encouraging computer aided preoperative planning (CAPP) orthopedic surgery, by emphasizing the study into bone fracture registration algorithms to improve correctness and accuracy of bone reduction. A concept and application program for 3D simulation based on personal computer presented, enabling surgeons to relocate fracture fragments onto their original position. This laboratory default software, named PhysiGuide, employed to deal with a comminuted fracture fragments reduction. Four different registration techniques proposed: pairs point, mirrored-bone, anatomy landmarks and fracture line constraints. A proximal femoral fracture generated from CT scans used for evaluating the performance of the proposed registration. Displacements distant of fragments after reduction are calculated and compared to healthy bones as a ground truth. The translation and rotation errors in repositioning calculation and the contact between fracture fragments should be within a clinically acceptable range. The experimental results show the lowest displacement and good stability obtained by using the method of fracture line constraint. The root mean square error is + 1.097 mm.