History of Cervical Spine Localization: Surface Landmarks.

Interest in the relational anatomy of the anterior neck among spine surgeons increased after the popularization of anterior cervical discectomy and fusion in the 1950s. Five surface landmarks and their relationship to specific spinal levels have been routinely described, comprising the angle of the mandible for the C2-C3 interspace, the hyoid bone for the C3 body, the thyroid cartilage for the C4-C5 disc, and the cricoid cartilage and carotid tubercle for the C6 body. We aimed to investigate the origins of these anatomic relationships and their application in modern practice.