Non-invasive ultrasound registration of the pelvic bone surface for THR

Introduction Registration of intraoperative ultrasound to preoperative CT data can be used to non-invasively locate bones of interest and allow for computer assisted surgical navigation of the operative field. Ultrasound (US) images of the pelvic surface, along with the respective position and orientation of each image are processed to provide a set of 3D points which define the location of the bone surface. The registration algorithm begins with an initial estimate from three anatomic landmarks and uses an adaptation of the iterative closest points (ICP) algorithm to refine the registration result [1]. The accuracy of the registration method was tested on an anatomic pelvis model using a fiducial based registration as the ground truth registration result. The development of minimally-invasive surgical techniques would benefit from the ability to non-invasively register the intraoperative anatomy to a preoperative surgical plan.