Anatomic and radiologic relationships of neck structures to cervical spine: implications for anterior surgical approaches

The position of the pharyngolaryngeal framework is very important in choosing the best surgical approach for cervical spine disease. The aim of the present paper is to investigate the position of the hyoid bone and cricoid cartilage in relation to the cervical spine. Moreover, the surgical implications for anterior transcervical approaches to the upper spine and the prevertebral space are discussed. To minimise complication rates and increase surgical effectiveness, the location and extent of the cervical spine disease should be evaluated in the context of the patient’s specific anatomy. A retrospective analysis of 100 cervical spine MRIs was conducted. Patients with diseases that could alter anatomic relationships of cervical structures were excluded. The mid-sagittal view of the hyoid and the inferior margin of the cricoid cartilage were projected perpendicularly to the anterior surface of the cervical vertebrae. The distance between these two landmarks was measured on the same view. The distribution of hyoid projections ranged between C2-C3 and C4-C5 intervertebral space, while the cricoid cartilage ranged between C4-C5 and C7-T1 intervertebral spaces. The mean distance between these two landmarks was 49.1 ± 7.7 mm, with statistically significant differences between males and females. The position of the cricoid cartilage significantly influenced the length of the pharyngolaryngeal framework, while the position of hyoid did not. A wide range of variability in the position of the hyoid bone and the cricoid cartilage in relation to cervical levels exists. This implies that an a priori association of a cervical level to neck structures at risk might be inaccurate. The use of these easily identifiable landmarks on pre-operative imaging may help to guide the choice among different anterior surgical approaches to cervical spine and reduce the risk of surgical complications.