Stylohyoid Ligament Injection

Indications and Clinical Considerations

Hyoid syndrome is caused by calcification and inflammation of the attachment of the stylohyoid ligament to the hyoid bone. Tendinitis of the other muscular attachments to the hyoid bone also may contribute to this painful condition. Hyoid syndrome also may be seen in conjunction with Eagle syndrome or as a sequela of traumatic injuries of the hyoid ( Fig. 12.1 ). The pain of hyoid syndrome is sharp and stabbing and occurs with movement of the mandible, turning of the neck, or swallowing. The pain starts below the angle of the mandible and radiates into the anterolateral neck. The pain of hyoid syndrome often is referred to the ipsilateral ear. Some patients also may report a foreign body sensation in the pharynx. Injection of the attachment of the stylohyoid ligament to the greater cornu of the hyoid bone with local anesthetic and corticosteroid will serve as both a diagnostic and a therapeutic maneuver.

Clinically Relevant Anatomy

The styloid process extends in a caudal and ventral direction from the temporal bone from its origin just below the auditory meatus. The stylohyoid ligament’s cephalad attachment is to the styloid process, and its caudal attachment is to the hyoid bone. In hyoid syndrome, the stylohyoid ligament becomes calcified at its caudal attachment to the hyoid bone ( Fig. 12.2 ). Tendinitis of the other muscular attachments to the hyoid bone may also occur, contributing to the pain symptoms.

The key landmark for injection when treating hyoid syndrome is the cornu of the hyoid bone at a point between the mandible and the larynx. This osseous process is more easily identified if the greater cornu of the hyoid on the opposite side is steadied. Given the relationship of the great vessels of the neck to the greater cornu of the hyoid, care must be taken when placing needles in this anatomic area.