A novel system for markerless intra-operative bone and bone fragment tracking

Fluoroscopic guidance is an integral tool in modern orthopedic surgery often used to track bones and/or bone fragments during a surgical procedure. However, relying upon this intra-operative 2D projective imaging modality for this purpose can challenge a surgeon's ability to interpret 3D position and orientation of any but the simplest bony anatomy. A number of object-tracking technologies have been developed to aid surgeons, but they have failed to be generalizable to a wider array of procedures, have required an unrealistic amount of time and effort to implement, or have unacceptably changed the flow of the surgery. This work describes a novel, general-purpose system for markerless, intra-operative bone tracking that seamlessly integrates into a surgical setting. The system uses a unique calibration object placed next to the patient, which provides a common reference for aligning multiple fluoroscopic images. This approach enables robust and expedient 3D object registration from only two semi-orthogonal 2D fluoroscopic images.