Dissection showed a simultaneous occurrence of complete developmental ossification of the left hyoid apparatus, variants of the vertebral artery, and a left superior vena cava in a 56-year-old male cadaver.
Developmental variants, posttraumatic and degenerative changes of the hyoid apparatus may result in variable degrees of ossification or calcification.
This unusual disorder should be considered in the differential diagnosis of facial and neck pain especially within the scope of manipulation of the upper cervical spine. Cervical spine manipulation may exacerbate existing pathological conditions of the stylohyoid apparatus, thereby irritating neurovascular structures, and induce a fracture. Developmental ossification of this apparatus might be associated with anomalies in the atlantic section of the vertebral artery which make the patient more susceptible to vertebrobasilar insufficiency. We conclude that extreme care should be taken in the presence of such an ossification to avoid trauma to the stylohyoid apparatus and maybe even because of increased vertebrobasilar risk (J Manipulative Physiol Ther. 2005;28:346-351).