Virtual 3D Bone Fracture Reconstruction via Inter-fragmentary Surface Alignment

This paper presents a system for virtual reconstruction of comminuted bone fractures. The system takes as input a collection of bone fragment models represented as sur-face meshes, typically segmented from CT data. Users in-teract with fragment models in a virtual environment to re-construct the fracture. In contrast to other approaches that are either completely automatic or completely interactive, the system attempts to strike a balance between interaction and automation. There are two key fracture reconstruction interactions: (1) specifying matching surface regions be-tween fragment pairs and (2) initiating pairwise and global fragment alignment optimizations. Each match includes two fragment surface patches hypothesized to correspond in the reconstruction. Each alignment optimization initialized by the user triggers a 3D surface registration which takes as input: (1) the specified matches and (2) the current position of the fragments. The proposed system leverages domain knowledge via user interaction, and incorporates recent ad-vancements in surface registration, to generate fragment re-constructions that are more accurate than manual methods and more reliable than completely automatic methods. 1