Temporal bone

Under the Temporal bone medicine understands a symmetrically laid out and extremely detailed brain skull bone. The temporal bone is an important part of the skull base and serves to stabilize the skull and to accommodate sensitive structures. A skull fracture can occur as part of a skull base fracture.

What is the temporal bone?

The temporal bone is a cerebral skull bone in the posterior region of the skull. The structure is symmetrical on both sides of the human skull. In medical terminology, the temporal bone is called the temporal bone and makes up one of the most differentiated bones in the human body.

Many structures of the middle and inner ear are housed in the temporal bone. As a socket, the temporal bone is even involved in the temporomandibular joint. The temporal bone is differentiated into four parts. In addition to the temporal bone scale (pars squamosa ossis temporalis) and the tympanic part (pars tympanica ossis temporalis), it contains a mastoid process with mastoid cells (pars mastoidea ossis temporalis) and the so-called petrous bone (pars petrosa ossis temporalis).

The temporal bone scale is sutured to the neighboring bones. The other structures of the temporal bone are wedged between the occiput, the sphenoid bone, the temporal bone scale and the parietal bone and are fixed by connective tissue. In animals, these structures are also called petrous pyramids because of their arrangement.

Anatomy & structure

The scale part is the largest section of the temporal bone in terms of area and is involved in the lateral wall of the cranial cavity. In front, it carries the zygomatic fors (processus zygomaticus ossis temporalis) of the zygomatic arch (arcus zygomaticus). The zygomatic arch forms a bar for the scale part at the back and extends over the entire surface of the scale.

The articular surface of the temporomandibular joint (fossa mandibularis) sits on the yoke process. The tympanic part of the temporal bone encircles the auditory canal (Porus acousticus externus) and is involved in the side wall of the tympanic cavity (Cavum tympani). The structure also forms the bony enclosure of the stylus process (processus styloideus). A fissure (fissura petrotympanica) separates the timpani part from the rock part. The wart part is equipped with a hollow mastoid process containing the mucous membrane. An opening (aditus ad antrum) connects the structure with the tympanic cavity.

There is also a connection to the hollow and air-filled mastoid cells (Cellulae mastoideae), which are connected to the nasopharynx via the middle ear. The petrous bone is the hardest skull bone and includes the inner ear.

Function & tasks

The cranial bone does not fulfill any active tasks, but it is an irreplaceable part of the skull base and serves for stability and the accommodation of important structures in the head area. It gives stability to various sensory organs and nerves in the head and also provides bony protection for sensitive structures.

In the gap between the timpani part and the rock part of the temporal bone, for example, the timpani cord (Chorda tympani) of the facial nerve (Nervus Facialis) lies. Through the holes and openings, many cranial nerves also enter the skull through the temporal bone, which are kept safe and stable thanks to the bones of the structure. The furrows in the cranial bone serve as a guide rail for various nerves and vessels. The anatomical structure is also perfectly tailored to the hearing organ. Therefore, deformities of the temporal bone can have a very negative effect on hearing.

The temporal bone is also the starting point for various muscles. The mastoid process of the anatomical structure offers, for example, the long neck muscles (sternocleidomastoid muscles). Since the temporal bone is also involved in the temporomandibular joint, it also indirectly plays a role in human ingestion and the chopping of food. Although the cranial bone is itself a passive structure, many of the head structures stored in it take on irreplaceable tasks in terms of perception, innervation and motor skills.

For this reason, injuries or malformations of the cranial bone can affect a wide variety of bodily functions that the layperson may not at first glance associate with the bony structure.

Diseases

In diseases such as Eagle Syndrome, there is a deformity of the temporal bone. The stylus process of the anatomical structure is over 30 mm long in Eagle Syndrome. The removal of the tonsils is currently being discussed as the cause of the syndrome. Most often, those affected suffer from a sore throat. A foreign body sensation or globus syndrome in the throat can also occur.

Pain in the throat is just as conceivable as pain on pressure in the tonsillar fossa. Pain sensations occur especially when swallowing and moving the throat. Atypical facial pain is also a common symptom. The incidence of Eagle syndrome is relatively high, with many sufferers remaining without noticeable symptoms. It is different with a fracture of the skull bone. This accident-induced phenomenon can, for example, cause inner ear damage that can progress to inner ear numbness. Inflammation of the temporal bone can also occur. This inflammation, as a rule, affects the mucous membranes of the anatomical structure.

The mastoid process of the temporal bone in particular is also a popular target for bacterial infections, which often spread from there to the ear. Ear infections with discharge can result. Tumor diseases can also occur in the temporal bone area. One of them is the so-called paraganglioma, which does not arise directly from the temporal bone, but occurs in its immediate vicinity. These tumors are the most common tumors of the middle ear area. Overall, however, they are comparatively rare. They arise from the nerve nodes in the middle ear and cause unspecific symptoms.