The adult human skeleton contains approximately 206 bones. Each of them has its own structure, location and function. Some bones help move, others protect our organs and tissues from mechanical damage, while others make it possible to perform actions such as chewing, swallowing and, of course, speaking. It is these functions that the hyoid bone and the muscles that attach to it perform. Despite its very small size, this bone is very important. Injuries associated with its fracture are extremely dangerous, they often end in death.
Anatomical structure
The hyoid bone is located directly under the body of the tongue. It can only be felt in thin people. Its size is relatively small, but it is involved in the performance of very important functions. Together with the muscles that connect to it, it helps to carry out processes such as chewing and swallowing. In addition, without it, human speech would be impossible. So re-evaluatethe value of this bone is impossible. The structure of the hyoid bone is simple. It is conditionally divided into the body, large and small horns. It connects to the rest of the bones through joints and ligaments. The body of the hyoid bone has the shape of an uneven plate, slightly convex in front. It has vertical and transverse ridges. The edges are also heterogeneous: the upper one is pointed, while the lower one, on the contrary, is slightly thickened. From the sides, the body is connected with the help of articular surfaces of cartilage with large horns. They move towards the back. Large horns are much longer and thinner than the body. At the ends, they can be found thickening. From the place where the large horn connects to the body, small horns depart. As a rule, they consist of bone tissue, but in some cases they remain cartilaginous. They are also connected to the body with the help of a joint. The ends of the small horns are enclosed in the stylohyoid ligament. Sometimes it contains one, less often several rather small bones.
Fracture of the hyoid bone and symptoms of damage to the pharynx
Fractures and injuries of the hyoid bone are quite rare. As a rule, this occurs as a result of blunt trauma to the submandibular region. In this case, a fairly strong mechanical effect should be exerted on this area. In some cases, a fracture can cause strangulation. This also happens when hanging. A fresh small fracture makes itself felt with fairly obvious symptoms. First of all, these are severe pains in the upper front of the neck when swallowing or chewing. Also in the area of the hyoid bone, a smallhematoma. On palpation, mobility and crepitus of the fragments are felt.
When the hyoid bone is severely injured, the mucosa ruptures. This is accompanied by quite heavy bleeding from the mouth. It occurs due to damage to the branches of the lingual or thyroid artery. Often this injury is fatal. Providing first aid for fractures of this nature is very difficult and not always effective.
It can be said that all injuries involving the hyoid bone (you can see a photo of its location in the article) are very dangerous for human he alth and even life.
First Aid
First aid for a hyoid fracture should be done quickly. With the appearance of heavy bleeding from the mouth, it is necessary to activate the process of blood clotting. This can be done by tamponade or cold application. If possible, try to ligate the external carotid artery. After an injury, the first hours are the most dangerous. It is very difficult to make any predictions because of the risk of asphyxia. If the pharynx ruptures, too much blood can be lost. Unfortunately, death often occurs before the ambulance arrives.
Indeed, it is extremely difficult to help a person when the hyoid bone is broken and the mucous membrane is torn. If there are all signs of asphyxia, then the best thing to do is to intubate the trachea and then tamponade the pharynx to reduce blood loss. After these complex manipulations, you need totransport the victim to the hospital as soon as possible.
Treatment
Treatment of injuries associated with a fracture of the hyoid bone consists in immobilization and complete elimination of all displacements of fragments. This can be achieved by the palpation method both from the side of the oral cavity and, of course, from the outside. The immobilization of the head and, what is very important, the neck is carried out with the help of a securely fixing corset. In severe cases, when the hyoid bone is severely damaged, plaster is applied to the shoulders and neck. But in practice, most often the retention of bone fragments in the correct position is achieved only with surgical reposition. Often such injuries entail a number of complications, so treatment should be as effective as possible.
Hyoid bone muscles
All muscles that are attached to the hyoid bone at one end are conventionally divided into two groups: suprahyoid and infrahyoid. They differ from each other in position and, accordingly, in functions. The suprahyoid muscles include:
- digastric;
- maxillofacial;
- stylohyoid;
- geniohyoid muscle.
They are all located above the hyoid bone and are directly attached to it. The digastric muscle consists of an anterior and posterior abdomen, which are interconnected by tendons. It is closely interconnected with another group of fibers. The posterior abdomen in its upper part is attached to the temporal bone. Going down, the latter is adjacent to the stylohyoid muscle and passes intointermediate tendon. It covers the body and the greater horn of the hyoid bone with a fixation loop. But before that, it penetrates the stylohyoid muscle, which has a fusiform shape. Another group of fibers extends from the lower jaw from its inner surface. The maxillofacial muscle is flat and wide. The bundles of its fibers are located transversely, they are directed towards and grow together, forming a tendon suture. On the side of the midline of the maxillary-hyoid muscle, the chin-hyoid muscle begins.
Suprahyoid muscle functions
The group of suprahyoid muscles performs one common function. They allow the hyoid bone to move up, down and sideways. It helps a person perform complex actions such as swallowing and chewing. Thus, it can be said that the suprahyoid muscles are involved in digestive and respiratory functions, albeit indirectly. Also, this group of muscle fibers, by raising the hyoid bone along with the larynx and lowering the lower jaw, contributes to the process of speech production.
Infrahyoid muscles
The infrahyoid muscles include the following: sternohyoid, scapular-hyoid, sternothyroid. They are also attached to the hyoid bone, but are located below it. So, the scapular-hyoid muscle begins at the top of the scapula. It has two large bellies, which are separated by an intermediate tendon. The sternohyoid muscle with its lower end is attached to the handle of the sternum. She also,like the scapular-hyoid fibers, its upper part joins the hyoid bone. The third group of muscles - sternothyroid - lies in front of the thyroid gland and trachea.
Functions of the infrahyoid muscles
The hyoid muscles, acting as a group, pull the hyoid bone together with the larynx downwards. But each of them performs one specific function. For example, the sternothyroid muscle selectively moves the thyroid cartilage down. But no less important is another function of the sublingual muscles. By contracting, they reliably strengthen the position of the hyoid bone, to which the suprahyoid muscle group is attached, at the same time lowering the lower jaw.
