THE CLINICAL SYNDROME

• Calcification and inflammation of the connection of the stylohyoid ligament to the hyoid bone are the root causes of hyoid syndrome.

• The origin of the styloid process is located directly below the auditory meatus on the temporal bone, and it extends in a caudal and ventral direction from that location.

• The stylohyoid ligament is attached to the styloid process at its cephalad insertion point, and it is attached to the hyoid bone at its caudad insertion point.

• The calcification of the stylohyoid ligament at its caudad connection to the hyoid bone is a characteristic feature of hyoid syndrome.

• It's possible that this painful condition is caused, at least in part, by tendinitis in the other muscles' attachments to the hyoid bone.

• Both Eagle's syndrome and Hyoid syndrome could be present in a patient at the same time.

• Patients who suffer from diffuse idiopathic skeletal hyperostosis are thought to be at a higher risk for developing hyoid syndrome due to the disease's tendency to cause calcification of the stylohyoid ligament.

• This is because of the disease's propensity for calcification of the stylohyoid ligament.

SIGNS AND SYMPTOMS

• The pain associated with hyoid syndrome is described as being "sharp and stabbing," and it is triggered by activities such as twisting the neck, moving the jaw, or swallowing.

• The discomfort originates below the angle of the jaw and spreads into the anterior-lateral neck; nevertheless, it is most commonly attributed to the ipsilateral ear.

• Some individuals report feeling as though there is something alien lodged in their pharynx.

• Both a diagnostic and therapeutic procedure can be accomplished by performing an injection of local anesthetic and steroid into the connection of the stylohyoid ligament to the larger cornu of the hyoid bone.

TESTING

• There is currently no diagnostic procedure available for hyoid syndrome.

• There is a possibility that calcification of the caudad connection of the stylohyoid ligament at the hyoid bone will be seen on plain radiography, computed tomography, or magnetic resonance imaging of the neck.

• Patients who suffer from the previously stated constellation of symptoms and have this calcification in their hyoids are strong candidates for having hyoid syndrome.

• If inflammatory arthritis or temporal arteritis is suspected, a complete blood count, erythrocyte sedimentation rate, and testing for antinuclear antibodies are all recommended tests to perform.

• As was mentioned previously, administering a very low dose of anesthesia through a needle placed at the point where the stylohyoid ligament attaches to the hyoid bone can be a useful diagnostic tool in determining whether or not this is the cause of the patient's pain.

• If difficulty swallowing is a prominent feature of the clinical presentation, an endoscopy of the esophagus must be performed, with particular attention paid to the gastroesophageal junction. This is necessary in order to identify esophageal tumors or strictures that are the result of gastric reflux.

DIFFERENTIAL DIAGNOSIS

• The hyoid syndrome is a diagnosis of exclusion, which means that the clinician must first consider and eliminate all other potential causes.

• The symptoms of sternohyoid muscle syndrome may be mistaken for those of hyoid syndrome.

• Sternohyoid muscle syndrome will manifest itself as a mass in the lower lateral neck that becomes visible as the patient swallows and then vanishes after swallowing is complete.

• Infections and tumors of the retropharynx have the ability to cause indistinct discomfort that is similar to the pain and other symptoms associated with hyoid syndrome. It is imperative to rule out the possibility of these potentially fatal diseases.

• It is also possible for hyoid syndrome to be a symptom of osteomyelitis of the hyoid bone, particularly in immunocompromised people.

• Another painful illness that has the potential to be misdiagnosed as hyoid syndrome is known as glossopharyngeal neuralgia.

• However, the pain of glossopharyngeal neuralgia is comparable to the paroxysms of shocklike agony that are associated with trigeminal neuralgia.

• Hyoid syndrome, on the other hand, is associated with the sharp, shooting pain that gets worse with movement.

• The clinician needs to be able to differentiate between the two symptoms since glossopharyngeal neuralgia can often be linked with significant cardiac bradyarrhythmias as well as syncope.

TREATMENT

• The local anesthetic and steroid injection that is placed at the attachment of the stylohyoid ligament is the most effective treatment for the pain associated with hyoid syndrome.

• This procedure should only be carried out by people who are well-versed in the anatomy of the surrounding region because to the high concentration of blood vessels in the area as well as its close proximity to neurological structures.

• When dealing with minor cases, it may also be beneficial to give nonsteroidal anti-inflammatory medications a try.

• Antidepressants, like nortriptyline, taken as a single dose of 25 milligrams before going to bed will help reduce sleep disturbances and treat any myofascial pain syndrome that may be present.

COMPLICATIONS AND PITFALLS

• When treating individuals who are assumed to be suffering from hyoid syndrome, the most common mistake that can be made is to neglect to discover some other underlying disease that may be responsible for the pain. This is the most common problem.

• If injection of the caudad attachment of the stylohyoid ligament is going to be part of the treatment plan, the clinician needs to keep in mind that due to the area's high vascularity and close proximity to major blood vessels, there is a higher risk of postblock ecchymosis and hematoma formation. The patient needs to be informed of this potential complication before the procedure is performed.