Abstract
We describe a method to guide the surgical fixation of distal radius fractures. The method registers the fracture fragments to a volumetric intensity-based statistical anatomical atlas of distal radius, reconstructed from human cadavers and patient data, using a few intra-operative X-ray fluoroscopy images of the fracture. No pre-operative Computed Tomography (CT) images are required, hence radiation exposure to patients is substantially reduced. Intra-operatively, each bone fragment is roughly segmented from the X-ray images by a surgeon, and a corresponding segmentation volume is created from the back-projections of the 2D segmentations. An optimization procedure positions each segmentation volume at the appropriate pose on the atlas, while simultaneously deforming the atlas such that the overlap of the 2D projection of the atlas with individual fragments in the segmented regions is maximized. Our simulation results shows that this method can accurately identify the pose of large fragments using only two X-ray views, but for small fragments, more than two X-rays may be needed. The method does not assume any prior knowledge about the shape of the bone and the number of fragments, thus it is also potentially suitable for the fixation of other types of multi-fragment fractures.
