Abstract: Surgical navigation systems and methods may match a model to an anatomy within sections defined by boundaries. Once the sections are matched, the sections as well as other portions of (e.g., the entire) model may be registered to an intraoperative scene. The model may be a three-dimensional model generated from a plurality of two-dimensional images of a portion of a body of a patient. The surgical navigation systems and methods may reduce and/or obviate a need for a marker, such as a fiducial, a tracker, an optical code, a tag, or a combination thereof during a medical procedure.