Openings of the external base of the skull. External base of the skull

The bones of the skull, connecting with each other, form a large number of cavities, recesses and pits.

On the brain skull there is an upper part - the roof of the skull and a lower part - the base of the skull.

The roof of the skull is composed of the parietal bones, partly the frontal, occipital and temporal bones. The base of the skull is formed by the orbital parts frontal bone, ethmoid, sphenoid, temporal, and occipital bones.

By separating the roof of the skull, you can study the internal base of the skull, which is divided into three cranial fossae: anterior, middle and posterior. The anterior cranial fossa is formed by the orbital part of the frontal bone, the ethmoidal plate of the ethmoid bone and the lesser wings sphenoid bone; the middle cranial fossa - mainly the cerebral surface of the large wings of the sphenoid bone, the upper surface of its body, as well as the anterior surface of the pyramid of the temporal bone; posterior cranial fossa -- occipital bone and the posterior surface of the petrous part of the temporal bone.

In the anterior cranial fossa are located frontal lobes cerebral hemispheres, in the middle - the temporal lobes, in the posterior - the cerebellum, pons and medulla. Each hole has a series of holes. The anterior cranial fossa has openings of the cribriform plate, connecting it with the nasal cavity. From the middle cranial fossa, the superior orbital fissure and the optic canal lead into the orbital cavity; the round hole leads into the pterygopalatine fossa and through it into the orbit; The foramen ovale and spinous foramen communicate the middle cranial fossa with the outer base of the skull. In the posterior cranial fossa there are several openings: the large one (occipital), which connects the cranial cavity with spinal canal; jugular, leading to the outer surface of the base of the skull, and internal auditory, leading to the inner ear.

Examining the skull from below, you can see that the base of the skull in its anterior section is covered by the bones of the face, which form the bony palate, consisting of the palatine processes upper jaws and palatine bones. In the middle and posterior sections, the base of the skull is formed by the lower surfaces of the sphenoid, occipital and temporal bones. They have a large number of holes, in particular jugular foramen between the occipital and temporal bones and a lacerated foramen between the petrous part of the temporal bone and the sphenoid bone.

The largest topographic-anatomical formations facial skull are the orbit, nasal and oral cavities.

The eye socket has the shape of a tetrahedral pyramid. Its medial wall is formed by the frontal process of the maxilla, the lacrimal bone, the orbital plate of the ethmoid bone and partly the body of the sphenoid bone; the upper wall - the orbital part of the frontal bone, the small wings of the sphenoid bone; lateral wall - large wings of the sphenoid bone and zygomatic bone; the lower wall is the upper surface of the body of the upper jaw. The orbit communicates with the cranial cavity through the superior orbital fissure and the optic canal; from the nasal - through the nasolacrimal canal formed by the lacrimal bone, the frontal process of the upper jaw and the inferior nasal concha; with the infratemporal and pterygopalatine fossae - using the lower orbital fissure, which is located between the large wings of the sphenoid bone and the body of the upper jaw.

Nasal cavity has top, bottom and side walls. It is divided by a bony septum located in the median plane. The septum is formed by the perpendicular plate of the ethmoid bone and the vomer. The upper wall of the nasal cavity is formed by the cribriform plate of the ethmoid bone, as well as the nasal and frontal bones; the lower wall - the palatine process of the upper jaw and the horizontal plate of the palatine bone; lateral walls - the upper jaw, the lacrimal and ethmoid bones, the inferior nasal concha, the perpendicular plate of the palatine bone and the medial surface of the pterygoid process of the sphenoid bone. The anterior opening of the nasal cavity, called the piriform opening, communicates it with environment; the posterior openings, choanae, face the outer base of the skull and connect the nasal cavity with the pharyngeal cavity.

The nasal cavity on the right and left is divided by the nasal conchae, located on its lateral wall, into three passages: lower, middle and upper. All of them are connected to each other by a common nasal passage located on the sides of the nasal septum. The nasal cavity communicates with the cavity of the skull, orbit, nasal and oral cavities, and the air sinuses. The upper nasal meatus communicates with the cranial cavity through the openings of the cribriform plate of the ethmoid bone, the middle one with the sinus of the upper jaw, with the cells of the ethmoid bone and with the frontal sinus. Posteriorly, at the level of the superior turbinate, the sinus of the sphenoid bone opens into the nasal cavity. The inferior nasal meatus communicates with the orbital cavity through the nasolacrimal duct. The nasal cavity also communicates with the pterygopalatine fossa through the sphenopalatine foramen and with oral cavity- through the incisive foramen.

The oral cavity is limited by bony walls only from above, in front and from the sides. Its upper wall is formed by the bony palate, composed of the palatine processes of the right and left upper jaws and the horizontal plates of the palatine bones; the lateral and anterior walls are formed by the lower jaw and the alveolar processes of the upper jaws. The oral cavity communicates through the incisive foramen with the nasal cavity, and through the greater palatine canal with the pterygopalatine fossa.

On the lateral surface of the skull there are the pterygopalatine, infratemporal and temporal fossae.

The pterygopalatine fossa is located between the bones of the facial and cerebral skull and is limited in front by the body of the upper jaw, on the medial side - palatine bone, behind - the pterygoid process of the sphenoid bone, and above - the body of this bone. It communicates with the nasal cavity, the middle cranial fossa, the foramen lacerum, the orbit and the oral cavity. The pterygopalatine fossa does not have a lateral wall and extends outward into the infratemporal fossa.

Infratemporal fossa located posterior to the body of the upper jaw, inward from the zygomatic bone and zygomatic arch and externally from the pterygoid process of the sphenoid bone. It forms part of the outer base of the skull. It is separated from the temporal fossa by the infratemporal crest.

The temporal fossa is a flat depression in which the temporalis muscle lies. The formation of the temporal fossa involves the temporal surface of the large wings of the sphenoid bone, the squama of the temporal bone, and partly the parietal and frontal bones.

The human skull is the bony base of the head, consisting of twenty-three bones, in addition to which there are three paired bones located in the cavity of the middle ear. The base of the skull consists of that part that is located below the edge that runs in front on the border of the infraorbital margin, behind along the frontal bone, in particular, its zygomatic process, and the infratemporal crest of the bone in the form of a wedge, the upper border of the external auditory canyon, as well as external protuberance of the occiput. External and are distinguished. Today we will look at the internal foundation. But before we begin to study this issue, let us consider what structure and functions the skull has, as well as its shape.

Forms and functions of the skull

The human skull performs several functions:

Protective, which is characterized by the ability to protect human brain and sensory organs from various injuries;

Supportive, consisting in the ability to accommodate the brain and primary departments respiratory and digestive systems;

Motor, characterized by articulation with the spinal column.

The human skull can be represented by one of the following forms: standard (cranial index), acrocephaly (tower-shaped) and craniosynostotic (fusion of the sutures of the cranial vault).

To better understand the anatomy of the skull, let's take a closer look.

Outer base of the skull

This is the customary name for the one that faces down and is covered in front by the bones of the face, and at the back the outer base is formed by the bony palate, processes in the form of wings, and medial plates that limit the choanae, separated by the vomer. Behind the pterygoid processes, the base is formed by bone in the form of a wedge, lower section pyramid, tympanic section, as well as the anterior portion of the occipital bone. External base of the skull, anatomical atlas its location will tell you, it has three parts: front, middle and back. Let's look at each of them in more detail.

Posterior part of the base of the outer

In the posterior section there is a vault of the nasopharynx, which is limited by the pharynx. A fascia is attached to the base of the skull, directed from the pharyngeal tubercle to the side, in front of sleepy channel pyramid bones temple to lower jaw. In the posterior part of the base there is a large occipital fissure and emissaries that connect the sinuses of the dura mater with the plexus of suboccipital veins, the vertebral vein and the subclavian artery.

Anterior section of the base of the outer

There are gaps here, through which nerves and blood vessels pass. The largest foramina, the role of which is very important, are located along the border that connects the stylomastoid fissure and the incisive foramen. The section of the base, which is located in front, includes the bony palate with the incisive and greater palatine canals. The choanae extend backward from the nasal cavity.

Middle section of the outer base

This area includes a torn gap that is located between bones such as the temporal, occipital and sphenoid. There is also a jugular ostium, located between the occipital bone and the temporal bone. In the same area there are such fissures as the sphenoid-petrosal and occipital.

Inner surface of the base of the skull

Skull base with inside contains three fossae: anterior, middle and posterior. According to its location, the anterior fossa is located above the middle one. And this one, in turn, fit above the back one. The cerebrum is located in the first two fossae, and the cerebellum is located in the posterior fossa. The demarcations between the fossae are represented by the edges of the sphenoid bone, which are located behind, as well as the upper level of the pyramids of the temple bones. IN the internal base of the skull is the surface of the skull, which is concave and has irregularities, it repeats the structure of the brain that is adjacent to it. Let's look at its structure in more detail.

Anterior fossa of the skull

The anterior cranial fossa is the deepest. It is formed by the edges of the wings of the bone in the form of a wedge and a protrusion that is located between the visual openings. Adjacent to this fossa in front are frontal sinuses, and below are the recesses of the ethmoid bone, the nasal cavity and sinuses. In front of the cock's comb there is a blind mouth, through which one follows small size vein that connects the superior sagittal sinus with the nasal veins. On both edges of the ethmoid bone there are olfactory bulbs, where they fit through the plate from the nasal cavity olfactory nerves. Arteries, nerves, and veins also pass through the ethmoid bone to provide the lining of the anterior fossa. IN internal base of the skull involves the placement of the frontal lobes in this pit cerebral hemispheres human brain.

Middle cranial fossa

The middle cranial fossa is separated from the posterior one with the help of the sella turcica and the tops of the pyramids of the temple bones. In the middle of the fossa there is a sella turcica, which is covered by a diaphragm that has a slit through which a depression appears, which has an ending in the form of a cerebral appendage. On the diaphragm in front of the funnel there is a chiasm of the optic nerves, on the sides of which there are so-called siphons of the carotid arteries. From them, in turn, the orbital arteries move away, they, together with optic nerves pass into the visual canyons. Thus, it involves placement in the middle fossa of the cavernous sinus, which is located away from the sella turcica. This place is where sleepy sleep takes place internal artery and higher carotid artery the walls of the sinuses contain the following nerves: trigeminal, cranial and oculomotor. They pass through the superior opening into the orbit. On the side of these nerves there are veins of the orbits and eyeball, which further enter the cavernous sinus. Behind the sella turcica on the vagus nerve between the sheets of one of the three meninges the motor nerve is located. Its branches go through the cracks of the round and oval shape of the cranial pit, which is located in the middle. At the back of the form there is a spinous fissure, through which the anterior artery of the dura mater passes into the cranial cavity. It also suggests the presence on both sides of the sella turcica in the fossa, which is located in the middle, of the brain. In front of the inner part of the temple bone, which has the shape of a pyramid, there is a cavity of the middle ear, an intraauricular cavity and a cavity in the mastoid process of the temporal bone.

Posterior cranial fossa

The posterior cranial fossa contains the cerebellum, medulla oblongata and pons. In front of the fossa on the inclined surface there is a bridge, the main artery with all its branches. There is a plexus of veins and stony sinuses. Everything is connected. The posterior fossa is almost entirely occupied by the cerebellum; above and on the sides of it there are sinuses: sigmoid and transverse. The cranial cavity and the posterior fossa are separated by the cerebellar tentorium, through which the brain passes. Let's consider what role it has.

Behind the pyramid of the temple bone is the auditory orifice; the facial orifice passes through it. auditory nerves and the membranous labyrinth. Below the auditory canyon, the glossopharyngeal, accessory nerves, vagus, and also the jugular vein pass through the ragged fissure. If you look below in the atlas, you can see that the hypoglossal nerve and its canal, as well as a plexus of veins, pass through the mouth of the hypoglossal nerve. In the middle of the posterior fossa there is a large occipital fissure, through which the medulla oblongata and its membranes, spinal arteries and root extend spinal nerve. Along the edge of the groove of the sigmoid sinus, several orifices open into the fossa located behind, allowing emissary veins and the meningeal branch of the occipital artery to pass through. The mouths and slits that connect the posterior fossa with other areas are located in its anterior parts. Thus, they are presented in three types: front, middle and rear.

Finally...

The features of the shape and structure of the human skull cannot be studied without analyzing its functions, just as it is impossible to imagine the functions of any organ without understanding its structure. Knowledge of the anatomy of the skull in medicine is undeniable. This science uses modern methods diagnostics The structure of the skull was learned through examination, dissection, study, and other things. Today we have the opportunity to study the external thanks to medical atlases that were created many years ago. This knowledge is of particular importance in medical sciences, since they make it possible to study abnormalities in the development of the skull, the structure of the veins and blood vessels of the brain. Studying the anatomy of the skull is especially important for neurosurgeons, traumatologists and maxillofacial surgeons. Knowledge helps them deliver correct diagnosis and prescribe proper treatment in case of various defects or diseases. And this, in turn, can save a person’s life.

Now we know what human scull. Anatomy of the internal base of the skull considered during training in medical universities. The base is a concave surface, which follows the structure of the brain. It contains many channels and holes and consists of three pits. Inner base The skull is the surface of the skull where the frontal lobes of the cerebral hemispheres are located, as well as the cerebellum, medulla oblongata and pons. Arteries, vessels, and nerves are also located here. All of them play a huge role in the normal functioning of the human body.

034. THE OUTLET HOLE OF THE FACIAL CANAL IS

1) groove of the greater petrosal nerve

2) subarc fossa

3) wall of the internal auditory canal

Stylomastoid foramen

5) carotid foramen

035. THE INLET HOLE OF THE DRUM STRING TUBE IS

1) wall of the carotid canal

2) bottom of the jugular fossa

Channel wall facial nerve

4) stylomastoid foramen

5) groove of the greater petrosal sinus

036. THE OUTLET HOLE OF THE TYMPAN TUBE IS

Cleft petrosal nerve

2) tympanomastoid fissure

3) petrotympanic fissure

4) the bottom of the rocky dimple

5) thylomastoid foramen

037. ANATOMICAL FORMATIONS OF THE ETRIBODY BONE ARE

1) blind hole

2) inferior nasal concha

Cockscomb

4) tear trough

5) nasolacrimal duct

038. THE ETHRODIMOUS BONE HAS THE FOLLOWING PARTS

Perpendicular plate

Orbital plate

Lattice Maze

cribriform plate

5) inferior turbinate

039. THE PROCESSES OF THE ETHIMODIMOUS BONE ARE THE FOLLOWING NASAL TURNACLES

Superior turbinate

Superior turbinate

Middle turbinate

4) inferior nasal concha

5) wedge-shaped shell

040. THE PARIETAL BONE HAS THE FOLLOWING EDGES

Sagittal edge

Frontal edge

3) wedge-shaped edge

Occipital margin

5) temporal edge

041. THE PROCESSES OF THE UPPER JAW ARE

Palatine process

Zygomatic process

Alveolar ridge

4) frontal process

5) styloid process

042. THE SURFACES ON THE BODY OF THE UPPER JAW ARE

Front

Infratemporal

Nasal

Orbital

043. THE UPPER JAW TAKES PART IN THE FORMATION OF WALLS

Glaznitz

Oral cavity

Nasal cavity

Infratemporal fossa

Pterygopalatine fossa

044. HOLES ARE PROMOTED ON THE LOWER JAW

1) sublingual

2) mandibular

3) facial

4) condylar

Submental

045. THE FOLLOWING FORMATIONS ARE LOCATED ON THE BODY OF THE LOWER JAW

Oblique line

2) pterygoid fossa

Digastric fossa

Mylohyoid line

5) coronoid process

046. THE FOLLOWING FORMATIONS ARE LOCATED ON THE BRANCH OF THE LOWER JAW

1) chin bone

Coronoid process

Condylar process

Tongue of the lower jaw

Chewing tuberosity

047. THE PROCESSES OF THE LOWER JAW ARE

Coronary

Condylar

3) chin

4) mandibular

5) nasal

048. ON ​​THE LOWER JAW THERE IS A TUBERLESS WHICH

CALLED

1) mandibular

2) chin

3) alveolar

4) coronal

Chewable

049. POINTS OF ATTACHMENT OF MUSCLES ON THE LOWER JAW ARE

Chewing tuberosity

2) submandibular fossa

Digastric fossa

Pterygoid tuberosity

Pterygoid fossa

050. THE INNER NASIAL CONCENTA HAS PROCESSES

Maxillary

2) orbital

Tearful

4) wedge-shaped

Lattice

051. THE SURFACES OF THE CHICKOMBONE ARE

Orbital

Temporal

Lateral

4) nasal

052. HOLES ARE DISTRIBUTED ON THE CHICKOMBONE

Zygomatic orbital

2) infraorbital

Zygomaticotemporal

Zygomaticofacial

5) jugular

053. CHICKOMBONE HAS PROCESSES

1) nasal

2) orbital

Temporal

Frontal

5) maxillary

054. LOCATED ON THE LACRIMAL BONE

1) ethmoidal groove

Posterior lacrimal ridge

3) front ridge

4) maxillary process

5) lattice labyrinth

055. PROCESSES OF THE PALATINE BONE ARE

1) palatine process

Orbital process

Sphenoid process

Pyramidal process nasal process

5) zygomatic process

056. THE PLATES OF THE PALATINE BONE ARE

Perpendicular

2) nasal

3) maxillary

Horizontal

5) lattice

057. THE HYPOGLOUS BONE HAS THE FOLLOWING PARTS

Body

Big horns

Small horns

4) head

058. THE EDGES OF THE OPENER ARE

Upper

Front

Rear

4) lateral

Lower

059. THE FOLLOWING BONES TAKE PART IN THE FORMATION OF THE ANTERIOR CRANIAL FOSSE

Sphenoid bone

Frontal bone

3) parietal bone

Ethmoid bone

5) temporal bone

060. THEY PARTICIPATE IN THE FORMATION OF THE MIDDLE CRANIAL FOSSA

1) frontal bone

2) occipital bone

Sphenoid bone

Temporal bone

5) ethmoid bone

061. THE FOLLOWING HOLES OPEN AT THE BOTTOM OF THE MIDDLE CRANIAL FOSSA

1) inferior orbital fissure

2) jugular foramen

Oval hole

Superior orbital fissure

5) sublingual canal

062. THEY PARTICIPATE IN THE FORMATION OF THE POSTERIOR CRANIAL FOSSA

1) sphenoid bone

2) zygomatic bone

Temporal bone

Occipital bone

5) parietal bone

063. JUGULAR HOLE LIMITED

1) sphenoid bone

Occipital bone

Temporal bone

4) parietal bone

5) frontal bone

064. THE LATERAL WALL OF THE ORBIT IS FORMED BY BONES

1) ethmoid bone

2) upper jaw

3) sphenoid bone

Cheekbone

Frontal bone

065. THE LOWER WALL OF THE ORBIT IS FORMED

Upper jaw

2) sphenoid bone

Palatine bone

Cheekbone

5) lacrimal bone

066. THE MEDIAL WALL OF THE ORBIT IS FORMED

Sphenoid bone

Ethmoid bone

Lacrimal bone

Upper jaw

5) zygomatic bone

067. THERE ARE THE FOLLOWING HOLES IN THE WALLS OF THE ORBITS

Posterior ethmoidal opening

Visual channel

Nasolacrimal duct

4) pterygoid canal

5) round hole

068. THE UPPER WALL OF THE NASAL CAVITY IS FORMED

Nasal bones

Nasal part of the frontal bone

* pairs of cranial nerves.

Facial part of the skull

Eye socket, orbita , has the shape of a tetrahedral pyramid.

The base of the pyramid is the entrance to the orbit, aditus orbitae.

The tip of the pyramid passes into the optic canal, canalis opticus.

Walls of the orbit: superior, medial, inferior, lateral.

Top wall, paries superior , educated:

1) orbital part of the frontal bone,

2) the small wing of the sphenoid bone.

Top wall structures:

Fossa of the lacrimal gland, fossa glandulae lacrimalis,

trochlear fossa, fovea trochlearis.

2. Medial wall, paries medialis , educated:

1) frontal process of the maxilla,

2) lacrimal bone,

3) orbital plate of the ethmoid bone.

4) body of the sphenoid bone,

5) orbital part of the frontal bone.

Structures of the medial wall:

Fossa of the lacrimal sac, fossa sacci lacrimalis,

Nasolacrimal duct, canalis nasolacrimalis,

Anterior ethmoidal opening, foramen ethmoidae anterius,

Posterior ethmoidal foramen, foramen ethmoidae posterius.

3.Lower wall, paries inferior , educated:

1) orbital surface of the upper jaw,

2) orbital surface of the zygomatic bone,

3) orbital process of the palatine bone.

Bottom wall structures:

Infraorbital groove, sulcus infraorbitalis,

infraorbital canal, canalis infraorbitalis.

4. lateral wall,paries lateralis , educated:

1) orbital surface of the greater wing of the sphenoid bone,

2) the orbital surface of the zygomatic process of the frontal bone,

3) the orbital surface of the frontal process of the zygomatic bone.

Lateral wall structures:

Zygomaticoorbital foramen, foramen zygomaticoorbitale.

Between the superior and lateral walls is the superior orbital fissure, fissura orbitalis superior, leading into the middle cranial fossa.

Between the lateral and inferior walls there is an inferior orbital fissure, fissura orbitalis inferior, which communicates the orbit with the pterygopalatine and infratemporal fossae.

nasal cavity,cavitas nasi , front opens pear-shaped aperture, aperture piriformis, which is limited:

on the sides - nasal notches of the upper jaws,

above - the lower edges of the nasal bones,

below - the anterior nasal spine.

Posteriorly, the nasal cavity communicates with the pharynx through joan, choanae, limited:

laterally - medial plates of the pterygoid processes of the sphenoid bone,

below – horizontal plates of the palatine bone,

above – the body of the sphenoid bone,

medially – by the vomer.

Bone septum of the nose, septum nasi osseum, educated:

perpendicular plate of the ethmoid bone,

opener,

nasal crest of the upper jaws and palatines.

Walls of the nasal cavity: upper, lower, lateral.

Upper wall,paries superior , educated:

1) nasal bones,

2) the nasal part of the frontal bone,

3) cribriform plate of the ethmoid bone,

4) the body of the sphenoid bone.

Bottom wall, paries inferior , educated:

1) palatine processes of the upper jaws,

2) horizontal plates of the palatine bones.

lateral wall,paries lateralis , educated:

1) nasal bone,

2) the nasal surface of the body and the frontal process of the maxilla,

3) lacrimal bone,

4) ethmoid labyrinth of the ethmoid bone,

5) perpendicular plate of the palatine bone,

6) medial plate of the pterygoid process of the sphenoid bone.

On the lateral wall there are three nasal conchae: superior, middle and inferior. The superior and middle turbinates are part of the ethmoid labyrinth. The inferior nasal concha is a separate (independent) bone.

Below the nasal turbinates are located nasal passages: upper, middle and lower.

1. Upper nasal passage,meatus nasi superior , limited by the superior and middle turbinates. Located in the posterior part of the nasal cavity and its posterior end reaches the sphenopalatine foramen, foramen sphenopalatinum.

The upper nasal passage opens:

Posterior cells of the ethmoid bone.

Above the superior nasal concha there is a sphenoethmoidal recess, recessus sphenoethmoidalis, into which the aperture of the sphenoid sinus opens , aperture sinus sphenoidalis.

2. Middle nasal passagemeatus nasi medius , located between the middle and inferior turbinates.

The middle nasal meatus opens:

Anterior and middle cells of the ethmoid bone,

Frontal sinus through the ethmoidal infundibulum, infundibulum ethmoidae,

Maxillary sinus through the cleft semilunaris, hiatus semilunaris.

3.Lower nasal passage, meatus nasi inferior , located between the inferior turbinate and the lower wall of the nasal cavity.

The lower nasal meatus opens:

Nasolacrimal duct.

Between the nasal septum and the nasal turbinates is located common nasal passage, meatus nasi communis .

Bone palatepalatum osseum , limited by the alveolar processes of the upper jaws and formed by:

palatine processes of the upper jaws,

horizontal plates of the palatine bones.

Structures of the bony palate:

Median palatal suture sutura palatina mediana,

Transverse palatal suture, sutura palatina transversa,

incisal hole, foramen incisivum, leading into the incisive canal, canalis incisivus,

Greater palatine foramen , foramen palatinum majus,

Small palatine foramina, foramina palatina minora.

temporal fossa,fossa temporalis , It is limited from above by the superior temporal line, from below by the infratemporal crest of the sphenoid bone.

Walls of the temporal fossa: anterior, medial and lateral.

Front wall,paries anterior , educated:

1) zygomatic process of the frontal bone,

2) the temporal surface of the zygomatic bone.

2. medial wall,paries medialis , educated:

1) the temporal surface of the squamous part of the temporal bone,

2) outer surface parietal bone in the area of ​​the wedge-shaped angle,

3) the temporal surface of the greater wing of the sphenoid bone.

3. lateral wall,paries lateralis , represented by the zygomatic arch.

infratemporal fossa,fossa infratemporalis , delimited from the temporal fossa by the infratemporal crest of the greater wing of the sphenoid bone.

Walls of the infratemporal fossa: anterior, superior, medial.

Front wall,paries anterior , educated:

1) tubercle of the upper jaw,

2) zygomatic bone.

Upper wall,paries superior , presented:

1) temporal bone,

2) the temporal surface of the greater wing of the sphenoid bone below the infratemporal crest.

medial wall,paries medialis , educated:

1) lateral plate of the pterygoid process of the sphenoid bone.

On the lateral side, the infratemporal fossa is covered by the ramus of the mandible. In front, through the inferior orbital fissure, it communicates with the orbit. From the medial side through the pterygomaxillary fissure, fissura pterygomaxillaris, communicates with the pterygopalatine fossa. The hole is open below.

Pterygopalatine fossa,fossa pterygopalatina , has four walls: anterior, superior, posterior and medial.

Front wall,paries anterior , presented:

tubercle of the upper jaw.

Upper wall,paries superior , educated:

the maxillary surface of the greater wing of the sphenoid bone.

Back wall,paries posterior , educated:

1) the base of the pterygoid process of the sphenoid bone.

Medial wall, paries medialis , presented:

1) perpendicular plate of the palatine bone.

The pterygopalatine fossa narrows downwards and passes into the greater palatine canal, canalis palatinus major.

In the external base, three sections are distinguished: anterior, middle and posterior, the relief of which is formed by the bones of the facial and cerebral skull.

Anterior section or base of the facial skull.

· In the middle there is a bony palate made up of the palatine processes of the upper jaws and horizontal plates of the palatine bones, bounded along the edge by the alveolar processes. The bony palate separates the cavities of the nose and mouth and the muscles of the soft palate are attached to it behind. The gums are located along the alveolar processes.

· Between the palatine processes of the upper jaws and the horizontal plates of the palatine bones there are palatine median and transverse flat sutures.

· Anteriorly in the bony palate lies the incisive foramen, which passes into the incisive canal for the nasopalatine vessels and nerve. On the surface there are transverse palatine grooves and between them palatine ridges, which smooth out with age.

· At the back there are large palatine foramina, which pass into the same canals - for the vessels and nerves of the same name.

· The pyramidal process of the palatine bone contains openings for the small palatine tubules for the vessels and nerves of the same name.

The lateral sections of the base of the facial skull (right and left) consist of the pterygopalatine fossa, the inferior orbital fissure and the infratemporal crest, the infratemporal fossa.

In the middle section (from the posterior edge of the bony palate and pterygoid processes to the anterior edge of the foramen magnum, styloid processes and external auditory foramina of the temporal bones) there are:

· posterior edges of the nasal septum, vomer and nasal ridge with the posterior spine, the sphenoid process of the palatine bone to delimit the choanae;

· pterygoid processes of the sphenoid bone with medial and lateral plates, a pterygoid fossa between them, a pterygoid notch and a pterygoid hook for attachment of the pterygoid masticatory muscles and pharynx;

Choanae - for transmitting air into the nasopharynx;

body of the sphenoid bone - external carotid and torn holes– for the internal carotid artery and nerve, large wings with holes: oval - for the second branch of the Y pair, spinous - for the middle meningeal artery;

· the pterygoid canal at the base of the pterygoid processes – for the corresponding autonomic nerves and vessels;

· spine of the sphenoid bone - attachment of the temporomandibular joint ligament;

· in the lateral sections – the infratemporal fossa and the mandibular fossa of the temporal bone, the retromandibular fossa,

· on the temporal bone - the mandibular fossa, the base of the zygomatic process - the articular tubercle for the temporomandibular joint, the sphenoid-petallous and petrotympanic fissures;

· at the top temporal pyramid- muscular-tubal canal for auditory tube and muscles eardrum;

basilar part occipital bone- pharyngeal tubercle - beginning of the pharynx.

In the posterior section (from the anterior edge of the foramen magnum to the external occipital protuberance and the superior nuchal line) there are:

· bottom surface of the pyramid; the tympanic part of the temporal bone is the lower edge of the external auditory opening;

· subulate, mastoid temporal bone;

jugular fossa, jugular notch, jugular foramen - for internal jugular vein and IX, X, XI pairs cranial nerves;

· stylomastoid foramen - exit of the facial nerve canal - UII pair;

· occipital condyles, condylar fossae behind them, canals of the hypoglossal nerves at the base of the occipital condyles;

Foramen magnum foramen magnum spinal cord and vertebral vessels;

· stony-occipital fissure filled with cartilage - synchondrosis;

· external nuchal crest and protuberance, inferior nuchal line for attachment of ligaments and muscles.

The temporal fossa is located in the anterolateral part of the vault, bounded above by the inferior temporal line and below by the infratemporal crest of the sphenoid bone. On the lateral side the temporal fossa has the zygomatic arch, and on the front there is the temporal surface of the zygomatic bone. It is filled with the temporal muscle and fiber of the interaponeurotic, subaponeurotic and deep temporal space. The superficial temporal vessels are located above the muscle. Downwards, i.e. at the lateral edge of the outer base of the skull, it passes into the infratemporal fossa. The border between them is the infratemporal crest of the sphenoid bone.

The infratemporal fossa has:

· upper limit along the infratemporal ridge;

· lower – along the base and lateral plate of the pterygoid process;

· anterior border – along the orbital edge of the sphenoid bone;

Posterior – along the edge of the base of the zygomatic process of the temporal bone.

The fossa is limited on the side inner surface branches of the lower jaw.

In the infratemporal fossa there is tissue of the temporopterygoid, interpterygoid and pterygomaxillary space, the pterygoid muscles and the maxillary artery pass nearby, part of the pterygoid venous plexus and the maxillary vein lie. Through the pterygomaxillary fissure, the fossa communicates with the pterygopalatine fossa.