Skeletal muscle take part in the formation of the walls of the oral cavity, abdominal cavity, pelvis, esophagus, larynx. They activate the auditory bones, the eyeball, they are involved in the function of breathing, chewing and swallowing. The muscles of the skull are divided into 2 groups: mimic and chewing.

The chewing muscles of the face (musculus masseter) are formed from the mesoderm of the first jaw arch. A characteristic feature is that in one part they attach to the mandibular bone, ensuring its movement, thereby participating in the processing of food. In addition, together with mimic ones, they provide swallowing, yawning, and speech.

There are 4 pairs of masticatory muscles:

• lateral pterygoid (m. pterygoideus lat.);
• medial pterygoid (m. pterygoideus med.);
• actually chewing (m. masseter);
• temporal (m. temporalis).

The anatomy of the masticatory muscles is simple, but its functions are very important.

Muscles of the chewing apparatus and their functions

Chewing muscles include 4 muscles.

Lateral (external) pterygoid

Runs horizontally. It has the shape of a triangle.

Start

The lateral pterygoid muscle is divided into 2 segments - the lower and upper heads.

They come from the outer plate of the pterygoid process and the greater wing of the sphenoid bone.

Attachment

The upper head of the muscle is attached to the articular bag, the lower - to the neck of the condylar process of the mandibular branch, uniting with the upper one.

Blood supply

It is carried out by the posterior and anterior pterygoid arteries. They belong to the section of the maxillary artery, being its branches.

Innervation

The lateral pterygoid nerve innervates this muscle. It belongs to the motor branch of the 3rd pair. Passes along with the deep temporal nerves and often together with the buccal nerve.

Functions

Pushes the mandibular bone forward when both muscles move, moves it to the side with unilateral contraction.

Functional muscle tests

Kinesiology is the science of the muscular functions of living organisms, which studies various aspects of movement.

A kinesiological test (functional muscle test) is a diagnostic direction both for assessing the work of one muscle and muscle groups connected into a single block, for example, performing similar functions.

The traditional functional test is the Herbst muscle test. They are necessary when trying on and correcting individual spoons when making full ones. You need to do the following:

• swallow saliva;
• open your mouth as wide as possible;
• run your tongue along the borders of both lips;
• touch the tip of the tongue to the cheek, during this the mouth should be partially open (halfway);
• try to touch your nose with your tongue;
• stretch your lips forward with a tube.

The muscular-functional consequence of these tests was the kinesiological testing of A.A. Davydov, bearing the name "Smiling Dentist". The patient is asked to do the following:

• smile as broadly as possible;
• say the letter "U", stretching out your lips;
• to push the mandibular bone downward and anteriorly to assess the state of tension of the chin muscle;
• stick out your tongue as much as possible;
• yawn without opening your mouth wide;
• swallow saliva.

The opening level is set using a triangle or occlusal gauge. If they are not available, use a ruler. Another way is to place the patient's fingers between the front teeth of the upper and lower jaws. The criterion for the normal state is the volume of the greatest opening of the mouth 4 cm (3-4 fingers folded across). There are 3 types of opening restrictions: light - 20-30 cm, medium - 10-20 mm, heavy - up to 10 mm.

Method for determining the functional efficiency of the lateral pterygoid fascia - opening the mouth:

• the patient is relaxed, looks straight ahead;
• the doctor looks at the patient, asks to push the mandibular bone forward, tightly closing his teeth.

Painful sensations and a small amplitude indicate muscle pathology.

Medial (internal) pterygoid

It looks like a quadrangle.

Start

Comes from the inner plate of the pterygoid process.

Attachment

It joins the pterygoid tuberosity on the mandibular bone.

Blood supply

Like the external pterygoid muscle.

Innervation

The medial pterygoid muscle is innervated by the medial pterygoid nerve.

It is the motor branch of the 3rd pair of the trigeminal nerve.

Functions

Raises the bone up.

Functional muscle tests

Closing the mouth:

• the patient is relaxed, looks in front of him;
• the dentist looks at the patient, asks to show tightly closed teeth;
• then palpates the fascia, asks to show tightly clenched teeth.

With functional impairment, pain occurs during lateral movements of the jawbone. For example, when yawning and chewing.

Chewing proper

The masseter muscle itself is subdivided into 3 segments: deep, middle and superficial.

Start

Coming from the cheekbone and arch.

Attachment

Attaches to the chewing tuberosity of the mandibular bone.

Blood supply

It is carried out at the expense of the chewing artery. It also belongs to the section of the maxillary artery.

Innervation

Carries out the nerve of the same name. Moreover, it gives off a sensitive branch to the capsule of the temporomandibular joint.

Functions

Raises the mandibular bone up. The superficial part of the fascia takes part in its forward movement.

Functional tests

Similar to tests for the medial pterygoid muscle.

Overvoltage m. masseter may cause (teeth grinding in sleep). It is a symptom of a head injury.

In this case, the functions of the chewing muscle proper begin to be performed by the temporal and internal pterygoid apparatuses.

Temporal

The temporalis muscle, which also belongs to the chewing apparatus, has a fan-like configuration, represented by 3 layers: outer, middle and inner.

Start

Occupies the entire temporal fossa. It starts from the frontal, parietal, temporal bones and the greater wing of the sphenoid bone. The fascia bundles, converging downward, go beyond the zygomatic arch to the attachment point.

Attachment

It joins the coronoid process of the mandibular bone.

Blood supply

It is carried out from the deep temporal artery, which belongs to the pterygoid section of the maxillary artery.

Innervation

It is carried out at the expense of the anterior and posterior deep temporal nerves, which have motor and sensory fibers. They move away from the mandibular nerve in the area of ​​the oval opening of the skull.

Functions

Raises the mandibular bone and pulls it posteriorly.

Functional muscle tests

The technique is the same. Muscle damage occurs with TMJ dysfunction () and tension headache. Functional ability should be assessed together with m. masseter and m. pterygoideus med. Stress test for a group of these 3 fasciae:

• the dentist passively opens the patient's mouth to the maximum level;
• if the action cannot be performed in the required volume and elastic resistance is felt, this is evidence of muscle shortening;
• the patient feels muscle tension.

Muscle functional tests in maxillofacial area help determine:

• balance or imbalance in functionally related muscle groups;
• participation in compensation or decompensation of functional and muscular disorders of the maxillofacial region;
• the level of progress or regression (wilting) of the muscles.

The patient can do these jaw muscle tests independently every day. It is necessary to adhere to a certain regimen after agreement with the doctor. Such exercises can significantly reduce the level of muscular-functional disorders of the maxillofacial region, as well as accelerate recovery.

Front scalene muscle with bilateral contraction tilts cervical spine spine forward, and with unilateral contraction - in its direction. With a fixed position of the spine, the muscle raises the 1st rib. The muscle starts from the anterior tubercles of the III-VI cervical vertebrae, the place of its attachment is the tubercle of the anterior scalene muscle of the 1st rib.

Average The scalene muscle, when contracted, tilts the neck forward, and when the neck is in a fixed position, it raises the I rib. The starting point of the muscle is located on the anterior tubercle of the six lower cervical vertebrae, and the attachment point is on the upper surface of the 1st rib.

Back scalene muscle raises the II rib, with a fixed position chest flexes the cervical spine forward. The muscle begins on the posterior tubercles of the IV-VI cervical vertebrae and attaches to the outer surface of the II rib.

Muscle group located under the hyoid bone (median muscles of the neck)

The thyroid-hyoid muscle, when contracted, brings the larynx and the hyoid bone closer together, and when the hyoid bone is in a fixed position, it raises the larynx. The point of origin of the muscle is on the oblique line of the thyroid cartilage, and the point of attachment is on the body of the hyoid bone.

The scapular-hyoid muscle expands the lumen of the internal jugular vein. With a fixed position of the scapula, it shifts the hyoid bone downward and outward and pulls off the vagina of the vascular cervical bundle. This thin and longus muscle has an upper abdomen and a lower abdomen, which are connected to each other by an intermediate tendon. The upper abdomen begins at the lower edge of the hyoid bone, the upper one - on the superior transverse ligament and the upper edge of the scapula. Connecting to each other, both abdomens are attached to the tendon bridge.

The sternohyoid muscle pushes the hyoid bone downward. The muscle begins on the posterior surface of the clavicle, the sternum arm and the capsule of the sternoclavicular joint, and attaches to the lower edge of the body of the hyoid bone.

The sterno-thyroid muscle displaces the larynx downward. The starting point of the muscle is located on the posterior surface of the sternum handle and the cartilage of the 1st rib, the attachment point is on the oblique line of the thyroid cartilage of the larynx.

Muscle group located above the hyoid bone (median neck muscles)

The digastric muscle, contracting, lowers lower jaw and pulls her back. With a fixed position of the lower jaw, this muscle raises the hyoid bone.

The muscle is so named because it is divided into the anterior abdomen and the posterior abdomen, which are connected to each other by a tendon bridge. The anterior abdomen begins in the digastric fossa of the lower jaw; the posterior abdomen has a mastoid notch of the temporal bone at its origin. Both abdomens attach to the body of the hyoid bone, passing into the tendon.

The stylohyoid muscle lifts the hyoid bone while simultaneously displacing it back and outward. This fine fusiform muscle begins at the base of the styloid process of the temporal bone and attaches to the body and horn of the hyoid bone.

The jaw-hyoid muscle raises the hyoid bone and, when it is in a fixed position, lowers the lower jaw.

The muscle itself is flat; connecting with the jaw-hyoid muscle of the opposite side, it forms the diaphragm of the mouth, or the bottom of the oral cavity. The starting point is the jaw-hyoid line of the lower jaw. The place of attachment of the main part of the muscle is located in the area of ​​the diaphragm of the mouth, connecting with the fibers of the main part of the opposite jaw-hyoid muscle and forming the jaw-sublingual suture of the diaphragm of the mouth. The attachment point of the posterior muscle bundles is on the anterior side of the hyoid bone.

The sublingual muscle raises the hyoid bone, displacing it forward, and with a fixed position of the hyoid bone, lowers the lower jaw. The muscle is located above the jaw-hyoid muscle, begins at the chin axis of the lower jaw and attaches to the anterior surface of the body of the hyoid bone.

Fasciae of the neck

The fascia of the neck consists of three plates and has a complex structure due to the large number of muscles and organs. The space between the fascia of the neck and the organs of the neck is filled with adipose tissue and loose connective tissue.

The superficial lamina is a continuation of the fascia of the chest and back. It forms the vagina for the submandibular gland and for the suprahyoid and sternoclavicular muscles of the neck. In the back of the neck, the fascia envelops the trapezius muscle, reaching the occipital protuberance and superior nuchal line. A suprasternal interaponeurotic space is formed above the jugular notch of the sternum handle.

The prevertebral plate begins at the base of the skull, descending, covers the prevertebral muscles of the neck, and also goes to scalene muscles... The posterior visceral space is located between the prevertebral plate and the organs of the neck.

The pretracheal plate begins at the clavicle and sternum handle and forms the sheath for the subhyoid muscles. The previsceral space is located between the pretracheal plate and the organs of the neck.

32. Mimic muscles: topography, structure, functions, blood supply, innervation.

In the process of contraction of the facial muscles, certain areas of the skin are displaced and the expression of the face changes. The facial muscles also reduce or enlarge the natural openings of the face: mouth, eyes, nostrils.

Each muscle or muscle group performs its own function.

Occipital-frontal muscle is divided into two parts: the occipital abdomen and the frontal abdomen.

By contracting, the occipital abdomen displaces the scalp along with the tendon helmet, which is a dense plate of tendons under the scalp, back to the back of the head, and the frontal abdomen forms transverse folds on the forehead, simultaneously raising the eyebrows and widening the eye slits. The occipital abdomen has a point of origin at the superior nuchal line of the occipital bone, and is attached in the posterior section of the tendon helmet. The frontal abdomen begins in the area of ​​the tendon helmet and is anchored in the skin of the eyebrows.

Brow muscle, when contracted, it shifts the eyebrows down and slightly inward, towards the bridge of the nose. In this case, two deep longitudinal folds are formed above the bridge of the nose, going up from the eyebrows. The point of origin of the muscle is located on the frontal bone above the lacrimal bone, and the attachment point is in the skin of the eyebrows.

Circular muscle of the eye consists of three parts: orbital, lacrimal and secular.

With the contraction of the orbital part of the muscle, the transverse folds of the forehead are smoothed, the eyebrows are lowered and the palpebral fissure narrows.

With the contraction of the secular part of the muscle, the palpebral fissure is completely closed.

Lacrimal part, contracting, expands the lacrimal sac. When combined, all three parts of the muscle are located in an ellipse. The origin of all parts is on the bones in the medial corner of the eye.

Orbital part forms a muscle ring, located along the lower and upper edges of the orbit, the lacrimal part goes around the lacrimal sac, covering it in front and behind, and the secular part lies in the skin of the eyelids.

Ear muscles includes three muscles: anterior, posterior and superior.

Front and upper muscles covered with temporal fascia. These muscles in humans are practically undeveloped. When they contract, the auricle moves slightly forward, backward and upward. The starting point of the ear muscles is the tendon helmet, and the attachment point is the skin of the auricle.

Nasal muscle divided into two parts: wing and transverse. This muscle is also poorly developed. With the contraction of the wing part, the wing of the nose drops, with the contraction of the transverse part, the nasal opening narrows. The starting point of the muscle lies on the upper jaw in the area of ​​the alveoli of the incisor and canine.

Mounting location wing muscle is located on the skin of the wing of the nose, and the transverse part - on the dorsum of the nose, where it connects to the opposite muscle.

In the area of ​​the cheekbones, the small zygomatic muscle and the greater zygomatic muscle are distinguished. Both muscles move the corners of the mouth up and to the sides. The starting point of the muscles is located on the lateral and temporal surfaces of the zygomatic bone; at the site of attachment, the muscles are intertwined with the circular muscle of the mouth and grow into the skin of the corner of the mouth.

Buccal muscle when contracting, pulls the corners of the mouth back, and also presses the lips and cheeks to the teeth. This muscle is the base of the cheeks. The muscle begins on the outer surface of the upper and lower jaw in the area of ​​the alveoli, at the pterygo-mandibular suture, and attaches in the skin of the lips and corners of the mouth, woven into the muscles of the upper and lower lips.

Muscle of laughter unstable, its task is to stretch the corners of the mouth to the sides. The starting point is located in the skin near the nasolabial fold and masticatory fascia, and the attachment point is in the skin of the corners of the mouth.

Circular muscle of the mouth represents muscle bundles, located in circles in the thickness of the lips. When shortening circular muscle the mouth is closed and the lips are extended forward. The starting point is located in the skin of the corner of the mouth, and the attachment point is in the skin in the midline region.

The muscle that lifts the upper lip, by contracting, raises the upper lip and makes the nasolabial fold deeper. The muscle begins at the infraorbital edge of the upper jaw and attaches to the skin of the nasolabial fold.

The muscle that lifts the corner of the mouth together with zygomatic muscles shifts the corners of the lips up and to the sides. The starting point is in the canine fossa of the upper jaw, and the attachment point is in the skin of the corner of the mouth.

Muscle lowering the corner of the mouth, when contracted, shifts the corners of the mouth down and to the sides. The origin of the muscle is located on the anterior surface of the mandible under the chin foramen. The place of attachment of individual beams is located in the thickness of the upper lip, the rest are woven into the skin of the corner of the mouth.

Muscle lowering the lower lip, pulls the lower lip down. This muscle is covered by the muscle that lowers the corner of the mouth; the starting point is the anterior surface of the lower jaw in front of the chin opening, and the attachment point is the skin of the chin and lower lip.

Chin muscle when contracted, it lifts the skin of the chin upward, forming dimples. The muscle is partially covered by the muscle that lowers the upper lip; begins at the alveolar elevations of the incisors of the lower jaw and attaches to the skin of the chin.

33. Chewing muscles: topography, structure, functions, blood supply, innervation.

Thanks to the chewing muscles, the chewing process is carried out as a result of the displacement of the lower jaw during their contraction.

The temporalis muscle raises the lower jaw, while the posterior muscle bundles pull it back, and the anterior ones - forward and upward. The muscle begins on the temporal surface of the greater wing of the sphenoid bone and the scaly part of the temporal bone, and attaches to the apex and medial surface of the coronoid process of the lower jaw.

Chewing muscles:

1 - temporal fascia:

a) surface plate, b) deep plate;

2 - chewing muscle:

a) deep part, b) surface part

The chewing muscle raises the lower jaw. It has the shape of an irregular rectangle and consists of a surface part and a deep part. The starting point of the superficial part is the anterior and middle sections of the zygomatic arch, and the deep one is the middle and posterior sections of the zygomatic arch. Both parts of the muscle are attached on the lateral side of the lower jaw branch along its entire length and to the corner of the jaw.

The lateral pterygoid muscle performs two functions: with a bilateral contraction (simultaneous contraction of both muscles), it pushes the lower jaw forward, and with a unilateral contraction, it shifts it sideways, in the opposite direction (in the direction opposite to the contracting muscle).

It is located in the inferior temporal fossa. The starting point is the temporal surface of the greater wing of the sphenoid bone, the lateral plate of the pterygoid process and the infratemporal ridge, and the attachment point is the medial surface of the temporomandibular joint capsule, articular process lower jaw and articular disc.

Chewing muscles (inside view):

1 - lateral pterygoid muscle;

2 - chewing muscle;

3 - medial pterygoid muscle

The medial pterygoid muscle, as well as the lateral, with bilateral contraction pushes the lower jaw forward, simultaneously lifting, and with unilateral contraction, it shifts in the opposite direction.

The muscle begins in the pterygoid fossa of the sphenoid bone and attaches to the inner surface of the mandible.

34. Muscles and fascia of the girdle upper limb: topography, structure, functions, blood supply, innervation.

Deltoid pulls the shoulder outward to the horizontal plane, while the front muscle bundles pull the arm forward, and the back ones - back. It is a thick, triangular muscle that covers the shoulder joint and part of the shoulder muscles. Its large beams converge in a fan-like manner to the apex of the triangle directed downward. The muscle starts from the axis of the scapula, acromion and the lateral part of the clavicle, and attaches to the deltoid tuberosity of the humerus. A subdeltoid bursa is located under the lower surface of the muscle.

Supraspinatus muscle has a triangular shape and lies in the supraspinatus fossa of the scapula, located directly under the trapezius muscle. The supraspinatus muscle raises the shoulder and retracts the capsule shoulder joint avoiding pinching. The point of origin of the muscle is located on the surface of the supraspinatus fossa, and the attachment point is on the upper platform of the greater tubercle of the humerus and on the posterior surface of the capsule of the shoulder joint.

Infraspinatus muscle turns the shoulder outward, pulls the raised hand back and pulls the capsule of the shoulder joint. This is a triangular flat muscle that fills the entire infraspinatus fossa. Its upper part is covered by the trapezius and deltoid muscles, and the lower part is covered by the latissimus dorsi muscle and the large round muscle.

The infraspinatus muscle starts from the wall of the infraspinatus fossa and the posterior surface of the scapula, and attaches to the middle platform of the greater tubercle of the humerus and the capsule of the shoulder joint. In the place of its attachment to the humerus, there is a tendonous sac of the infraspinatus muscle.

Small round muscle turns the shoulder outward, at the same time slightly pulling it back, and pulls off the capsule of the shoulder joint.

Oblong, rounded muscle, top part which is adjacent to the infraspinatus muscle, the front part is covered deltoid muscle, a rear part- a large round muscle. The starting point is located on the posterior surface of the scapula below the infraspinatus muscle, and the attachment point is on the lower platform of the greater tubercle of the humerus and the posterior surface of the capsule of the shoulder joint.

Big round muscle turns the shoulder inward and pulls it back, bringing the arm to the torso. Oblong flat muscle, adjacent to the latissimus dorsi muscle and partially covered by it in the posterior region. In the outer section, the large round muscle is covered by the deltoid muscle. The starting point is the posterior surface of the scapula at its lower angle, the attachment point is the crest of the lesser tubercle of the humerus. Near the attachment site, there is a pouch of the large round muscle.

Subscapularis muscle in extends the shoulder inward and takes part in bringing it to the body. Flat broad muscle triangular in shape, filling the entire subscapular fossa. It begins on the surface of the subscapular fossa, and ends on the lesser tubercle of the humerus and on the anterior surface of the capsule of the shoulder joint.

At the attachment site, there is a small subscapularis muscle pouch.

Fascia of the upper limbs

The subcutaneous fascia of the upper limb is poorly expressed. The fascia itself, along its entire length, differs in different thicknesses, its individual plates are highly developed and form sheaths for muscles and tendons, lining pits and canals. Depending on the muscle groups covered, fascia is secreted shoulder girdle, fascia of the shoulder, fascia of the forearm and fascia of the hand.

The chewing muscles are so named because they are involved in the complex process of mechanically grinding food. They also provide movement of the lower jaw. Due to this, a person can close and open his mouth, talk, yawn, etc. The chewing muscles are fixed on the bones in the same way as others. They are fixed with two ends. The movable part of the muscles is fixed on the lower jaw. The motionless one is fixed on the bones of the skull. All muscles involved in chewing food and moving the lower jaw have a normal structure. They have a muscular part. It can contract and move the lower jaw.

Views

There are much fewer than, for example, mimic ones. There are four of the first ones. However, they perform the most important functions, including ensuring the preservation of the "corner of youth". These include muscles:

1. Temporal.
2. Chewable.
3. Lateral and medial pterygoid.

All these elements form a single structure. With shortening or deformation of one of them, the rest are also subject to changes.

Lateral pterygoid muscle: photo, short description

It has two heads. They are separated by their own connective sheath (fascia). The lateral pterygoid muscle starts from the bone at the base of the skull. In this case, the beams move away from different points. The narrower (upper) protrudes from the infratemporal region of the greater wing in the sphenoid bone, as well as from the infratemporal ridge. The wider (lower) bundle comes out from the side. It starts from the pterygoid lateral plate in the fibers unite upon reaching the attachment point.

Lateral pterygoid muscle: functions

It should be said that this muscle element has a variety of connections with other facial structures. If l atheral pterygoid muscle will begin to function poorly or will undergo deformations, this may affect the activity of other systems. Dysfunction of this element can cause the development of a variety of symptoms and disorders, including hearing loss. Lateral pterygoid muscle provides jaw extension. This is achieved by simultaneous contraction of the beams on the right and left. If only one side is engaged, the jaw moves in the opposite direction. For example, when the right bundle contracts, it moves to the left, and vice versa.

Medial element

This muscle is presented in the shape of a quadrangle. She acts as essential element mandibular ligament. The muscle is located on the inner surface of the bone, opposite the chewing bone, in the same direction with it. In some cases, their bundles are connected. The element is fixed with thick processes. There are two of them. The larger one is attached to the pterygoid lateral part in the sphenoid bone, the smaller one - at the pyramidal process in the palatal part and the tubercle on the bottom, the muscle is also fixed at two points. Many important structures are formed between the processes. Among them are nerves, alveolar, maxillary vessels. The medial element, as well as, provides the movement of the lower jaw. When contracting on both sides, the bone moves forward and upward, on one side - to the side.

Chewing element

This muscle is located on top of the pterygoid (medial and lateral). She is quite strong because she trains more often than others while chewing. Its contours are quite well felt, especially when it is in a contracted state. The muscle is fixed on the zygomatic arch. It has a rather complex structure. are divided into deep and superficial parts. The latter departs from the middle and anterior sections of the zygomatic arch. The deep part is attached a little further. It departs from the back and middle sections of the arc. The surface feature runs back and down at an angle. In doing so, it covers the deep part.

Temporal element

This muscle departs from three bones at once. The temporal element occupies almost 1/3 of the surface of the skull. In its shape, the muscle resembles a fan. The fibers are directed downward and pass into a rather powerful tendon. It is fixed on the lower jaw. This muscle provides biting movements. In addition, she pulls the lower jaw forward, and also raises it until it closes with the upper one. The temporal jaw does not have a pronounced relief. However, she is directly involved in the formation of "sunken temples". With weight loss or frequent nerve stress, the muscle takes on a thinner and flatter shape. The temporal line and zygomatic arch at the same time acquire a relief. It is in this case that the face looks emaciated. With dysfunction or spasm, it is very difficult to detect changes in it.

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The masticatory muscles include 4 pairs of muscles that make movements in the temporomandibular joint and begin at the base of the skull (Fig. 1-6).

1. Chewing muscle(the so-called masseter) consists of three parts: superficial, intermediate and deep. Superficial part (pars superficialis) starts from the lower edge and outer surface of the zygomatic bone; muscle bundles are attached to the outer surface of the branch and to the body of the lower jaw in the corner. Muscle fibers run from top to bottom and front to back.

Intermediate part (pars intermedia) starts from the inner surface of the zygomatic arch of the temporal bone; it is attached by a tendon to the outer surface of the lower jaw branch below its notch, with the anterior fibers woven into the superficial part.

Rice. 1. Chewing and temporal muscles:

a - the temporal muscle is closed by the fascia: 1 - the zygomatic bone; 2 - upper jaw; 3 - the superficial part of the masseter muscle; 4 - the intermediate part of the masseter muscle; 5 - zygomatic arch; 6 - surface plate of the temporal fascia; 7 - temporomandibular joint; 8 - fiber in the temporal interaponeurotic space; 9 - superficial plate of the temporal fascia

b - temporal and masseter muscles after removal of the temporal fascia: 1 - temporal muscle; 2 - chewing muscle;

c - temporal muscle (zygomatic arch and part of the masseter muscle removed): 1 - temporal muscle; 2 - coronoid process of the lower jaw; 3 - chewing muscle; 4 - temporomandibular joint

Rice. 2. The chewing and temporal muscles (the zygomatic arch is sawn off and drawn with the chewing muscle):

1 - temporal muscle; 2 - coronoid process of the lower jaw; 3 - the intermediate part of the masseter muscle; 4 - deep part of the masseter muscle; 5 - zygomatic arch (sawn off); 6 - lateral pterygoid muscle; 7 - condylar process of the lower jaw; 8 - temporomandibular joint; 9 - articular disc

Deep part (pars profunda) begins muscularly from the inner surface of the zygomatic arch and temporal fascia; attaches to the outer surface of the coronoid process of the lower jaw and the tendon of the temporal muscle.

Function: raises the lower jaw; the deep part participates in the displacement of the jaw back and in its direction.

Innervation: chewing nerve.

2. The temporalis muscle (t. Temporalis) has a fan-shaped shape, fills the temporal fossa and consists of three layers: superficial, middle and deep.

Rice. 3. Pterygoid muscles, lateral view (temporal muscle turned away; part of the branch of the lower jaw sawn off):

1 - temporal muscle; 2 - medial pterygoid muscle; 3 - lower head of the lateral pterygoid muscle; 4 - upper head of the lateral pterygoid muscle; 5 - temporomandibular joint

Surface layer (stratum superficialis) starts from the temporal fascia and the superior temporal line; attaches to the apex and outer surface of the coronoid process, to the oblique line, and also to the notch of the lower jaw.

Middle layer (stratum mediale) is the most powerful, it begins muscularly from the temporal surfaces of the scaly part of the temporal bone, the large wing of the sphenoid bone, the frontal process of the zygomatic bone, parietal and frontal bones; is attached with a thick tendon to the coronoid process of the lower jaw, to its inner and outer surfaces, to the temporal crest and oblique line.

Deep layer (stratum profundum) begins muscularly from the temporal surface and infratemporal crest of the sphenoid bone, from the frontal scales and the temporal surface of the zygomatic bone. It is attached muscularly to the inner surface of the coronoid process, the anterior and middle thirds of the edge of the notch of the lower jaw, to the temporal ridge.

Rice. 4.

1 - temporal muscle; 2 - chewing muscle; 3 - medial pterygoid muscle; 4 - lower head of the lateral pterygoid muscle; 5 - upper head of the lateral pterygoid muscle; 6 - articular disc; 7 - zygomatic arch

The anterior bundles of the temporal muscle go down and back, the middle ones go vertically down, the back ones go back to front and slightly down.

Function: the anterior and middle muscle bundles raise the lower jaw, the posterior ones pull it back.

Innervation: deep temporal nerves.

3. Lateral pterygoid muscle(t. pterygoideus lateralis) is located in the infratemporal fossa, medial to the branch of the lower jaw. The muscle consists of two heads: upper and lower.

Upper head (caput superior) originates from the anterior part of the infratemporal surface and infratemporal crest of the greater wing of the sphenoid bone, as well as from the anterior muscle-tendon fibers of the deep layer of the temporal muscle. Direction muscle fibers- front to back, horizontally, from inside to outside. Attaches to the joint capsule and the disc of the temporomandibular joint.

Rice. 5. Places of origin and attachment of the masticatory muscles:

1 - the beginning of the temporal muscle; 2 - the beginning of the lateral pterygoid muscle; 3 - the beginning of the superficial part of the masseter muscle; 4 - attachment of the superficial part of the masseter muscle; 5 - attachment of the intermediate part of the masseter muscle; 6 - attachment of the temporal muscle and the deep part of the masseter muscle

Lower head (caput inferior) starts from the outer surface of the lateral plate of the pterygoid process of the sphenoid bone and attaches to the pterygoid fossa on the neck of the lower jaw.

Rice. 6. Places of muscle attachment on the inner surface of the lower jaw:

1 - temporal muscle; 2 - lateral pterygoid muscle; 3 - medial pterygoid muscle; 4 - maxillary-hyoid muscle; 5 - upper pharyngeal constrictor; 6 - buccal muscle

Function: with bilateral contraction, it pushes the lower jaw forward, with unilateral contraction, it shifts it in the opposite direction.

Innervation: lateral pterygoid nerve.

4. Medial pterygoid muscle(t. pterygoideus medialis) is located medially from the branch of the lower jaw. It starts from the pterygoid fossa of the pterygoid process of the sphenoid bone, the pyramidal process of the palatine bone, the lateral plate of the pterygoid process and from the hook of its medial plate. Attaches to the body, angle and pterygoid tuberosity on the ramus of the lower jaw. Muscle bundles go from top to bottom, front to back and from the inside to the outside.

Function: with bilateral contraction, it raises the lower jaw, with unilateral contraction, it shifts it to the side opposite to the contracted muscle.

Innervation: medial pterygoid nerve.

With fractures of the lower jaw, the function of each of the masticatory muscles is realized differently than normal, and depends on how the fracture line passes. So, if the fracture line passes through the neck of the lower jaw, then the superficial part of the masseter muscle and the medial pterygoid muscle displace the lower jaw (without condylar processes) anteriorly and upward.

Human anatomy S.S. Mikhailov, A.V. Chukbar, A.G. Tsybulkin

Quadriceps consists of 4 different muscles working together. That is why they have a common name. During the barbell squat, the quadriceps work longitudinally. As a result, the legs in the lateral projection become wider. Along with the side projection, there is also a frontal one, which should also have a decent look. How can this be achieved? It is necessary to pump the adductor muscles, which are located on the inner thighs. According to physiology, these muscles account for up to 30% of the total volume of the leg muscles.

However, there is another subtlety here - the lateral muscle, which is part of the quadriceps, is displaced from the central axis of the thigh outward. The development of this muscle forms the so-called "breeches", visually increasing the volume of the leg. So you just need to swing this muscle? That's right, all that remains is to pick up correct exercise for this.

In general, there are two best exercises for pumping up the quadriceps:

• Lunges;

Which of these exercises will allow you to pump up "breeches"? Let's figure it out.

Hack squats

When performing this exercise, the buttocks are actively involved in the work, which work together with the lateral muscle. Their work is identical to the work of the back and biceps or chest and triceps. That is, the lateral muscle receives a good portion of the load. However, the standard hack squat is not suitable here. To include in work lateral muscles, it is necessary to slightly change the technique of the exercise - put your feet at a distance of 20 cm from each other.

Barbell lunges

This exercise also includes the work of the buttocks, but the adductors of the inner thigh come to their aid. At the same time, the wide lateral ones are almost completely freed from the load. This exercise does not suit us.

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