An Accurate Technique for Registration of the Anterior Pelvic Plane Using Multiple Fluoroscopic Views

Accurate assessment of the orientation of the pelvis on the operating table is a crucial step for a number of surgical procedures in orthopaedics. The anterior pelvic plane (APP) has been traditionally used as a reference in various pelvic surgeries including a number of trauma, reconstruction and arthroplasty applications. The APP is either manually traced by over the skin palpation in conventional methods, or is identified by digitization or image-based registration techniques in a computer-assisted approach. Manual palpation has limitations because of the presence of a thick layer of soft tissues covering the landmarks and difficulties in accessing these landmarks in a lateral patient pose. Image-based navigation techniques require access to a three-dimensional model produced from a pre-operative image of the patient, and can increase the time of surgery significantly for registration. A quick and accurate method for registering the position and orientation of the pelvis without the need for a three-dimensional image can be a critically important component of a surgical navigation or an image-guided device, with significant impact on efficiency and quality of the surgery.