Hyoid Bone
Hyoid Bone Definition
The specification of the hyoid bone is to provide the support to the tongue and also assists in tongue movement and deglutition.
The speech is possible only due to presences of a small bone pendant in the neck muscle. In human anatomy, this horseshoe-shaped bone is termed as hyoid bone. The term hyoid bone comes from a Greek word derived from hyoeides means “the shaped which is similar to the alphabet upsilon” (υ).
Articulation of hyoid bone with other bones is conducted distantly by muscles or ligaments. Other than tongue, the structures which are attached to hyoid bone include larynx, pharynx and epiglottis. Human and Neanderthals are only having specific location of hyoid bone in animal kingdom.
Anatomy
Anatomically hyoid bone has three major parts which are body, greater and lesser cornua. The central part is considered as body and the both side is considered as cornua.
In last trimester, fetus starts to ossification of greater coruna and after birth within one two years of the age of the child, lesser cornua developed.
After fully developed hyoid bone, lesser cornua are similar with conical projections which leaning upward directions, while greater cornua pull out at the backward side. The pair off of the lesser and greater cornua can be distinguish into right and left sections.
Location
The space found in between the thyroid cartilage and chin, hyoid bone is present. The mandible is present at the base of the hyoid bone. Hyoid bone is the exceptional skeletal bone, which has not distinct articulation with other major bone.
Functions
The oral muscular structures such larynx, pharynx and epiglottis are attached to the hyoid bone and also perform specific functions which include voice generation and deglutition. Not only attachment, hyoid bone also gives shield to the attached muscles.
Ossification of hyoid bone initiate speech to the human child, as it provides support to tongue. It lifts larynx during deglutition. The specific location of hyoid bone, that is attached to the tongue and larynx allow human to make different sounds generated at the voice box.
Problems (Pain, Fracture)
The diagnosis of the underlying cause of any discomfort is very important. CT scan is one of the important diagnostic tools for identifying the underlying cause related to hyoid bone dislocation. Hyoid bone dislocation is medically termed as symphysis.
One of the major problems is a fracture of the hyoid bone. This is happened when any direct injury occurs in the neck. Usually Forceful injury is mainly affected hyoid bone fracturing. The possible injuries which affect directly on hyoid bone are blunt trauma, hanging, manual strangulation or projectiles.
The falling down rarely cause hyoid bone fracture, the chances are there if the victim falls through a contusion of the neck from high altitude. Excessive force on neck muscle causes the fracture of hyoid bone. Forced strangulation or choking is the resultant of broken of the hyoid bone.
Adult epiglottis is another hyoid bone related problem, though the event is rare. This condition is followed with airway obstruction which may become a life threatening condition for the victim. The physical examination can help to detect acute epiglottis, finding of tenderness over the hyoid bone is a major sign of this condition.
Traumatic injury at the greater cornu causes pain in the hyoid bone and this pain is radiated to other associated sites mainly felt at ear, throat, upper and lower jaw, molar teeth, facial region and temple bone. This pain extends to arm, breast and shoulder in the severe cases on the same side of the affected area.
Some case histories also demonstrate that the intermediate tendon present at digastric muscle affected with tenosynovitis.
The management of these problems can be conducted in the following way:
- In case of hyoid bone fracture, the main concern is air passage and clinician mainly concentrate to ensure there is no obstruction in the air passage.
- The nutritional intake is another important concern in case of hyoid bone fracture, as this bone assists in deglutition. Usually doctors recommended liquid or soft diet. But in severe case, when patient unable to swallow, then NasoGastric Tube feeding is the only option to manage the condition.
- Surgical intervention can be conducted to reset the hyoid bone or mange the dislocation.
- In case pain generated in the hyoid bone can be managed by injecting a combination of depomedrone and lignocaine.
- In case of severe pain, surgical removal of the greater cornu provides marked resolution of the problem. Before surgical re-sectioning of greater cornu, local anaesthetic is incorporated in the site.
- It is highly recommended medical advice is very necessary in case of any discomfort associated with hyoid bone to avoid unnecessary complications. This also suggested that diagnosis is important for avoiding of surgical intervention in case of non severe cases.
References
- http://www.healthline.com/human-body-maps/hyoid-bone
- https://www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/the-skeletal-system-7/the-hyoid-bone-80/the-hyoid-bone-466-4817/
- http://www.omgfacts.com/nerd/5217/The-hyoid-bone-is-the-only-bone-in-the-human-body-not-connected-to-any-other-ab964-1
- http://www.sciencedirect.com/science/article/pii/S2211558712000349
- http://pubs.rsna.org/doi/abs/10.1148/72.6.872
- http://www.triomeetingposters.org/wp-content/uploads/2012/12/046.pdf
- http://www.practicalpainmanagement.com/pain/maxillofacial/hyoid-bone-syndrome
- http://www.jabfm.org/content/19/5/517.full
- http://www.ncbi.nlm.nih.gov/pubmed/7989833