Left subclavian artery anatomy. Anatomy and branches of the subclavian artery

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The subclavian artery and its branches is a paired organ, since it includes two parts that feed the organs of the upper body. As part of the systemic circulation, it is an important part of the system, which must deliver blood without interruption.

Structure

The right subclavian artery arises from the brachiocephalic trunk. The base of the left side is determined by the beginning of the aortic arch. Conventionally, this artery can be divided into several parts:

scalenus ant. Its location is defined as the distance from the origin to the inner edge of the anterior scalene muscle.
spatium interscalenum. It is limited by the limits of the interstitial space.
axillaris. It starts at the outer edge of the anterior scalene muscle and stretches to the axillary artery in the middle of the clavicle.

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The length of the left subclavian artery is longer - its length differs by 2-2.5 cm.

Functions

The subclavian artery transports blood through its branches to the organs. So, she interacts with the following departments:

The first: blood goes through the vertebral artery to the spinal cord - the dorsal and hard shell of the brain, as well as to the muscles. In the lower part, the supply through the thoracic artery is carried out to the diaphragm, bronchi, mediastinal tissues, and the thyroid gland. Also, nutrition is supplied to the sternum, rectus abdominis and chest.
Second: along the costocervical trunk, blood goes to the spinal cord and muscles.
Third: blood flows to the muscles of the shoulders and back through the transverse artery of the neck.

Obliterating atherosclerosis and endarteritis, post-embolic and post-traumatic obliterations, as well as Takayasu's disease can contribute to occlusion. The active development of the disease in combination with thrombosis can lead to cerebral ischemia.

Question:

I kindly ask you to answer me this question. I did an ultrasound scan, the diagnosis was atherosclerosis of the right subclavian artery (the intima-media complex was thickened up to 1.5 mm at the mouth of the right subclavian artery). I am very concerned. Tell me if this is dangerous and what needs to be done to stop this process? I look forward to your reply. Thank you in advance.

Answer:

Thickening of the intima is not a cause for concern. However, it is advisable to check the level of cholesterol in the blood.

SUBCLAVIAN STEAL SYNDROME honey.

Subclavian steal syndrome - cessation of blood flow along the branches of the proximal subclavian artery, which supplies blood to the upper limbs, as a result of which blood enters this section from the system of the arterial circle of the brain, which leads to ischemia of the brain tissue; maximum manifestations - during physical activity.

Etiology

Damage to the vascular wall itself - atherosclerosis (95% of cases), nonspecific arteritis, specific arteritis (in particular, syphilitic)

Pathological tortuosity of arteries, displacement of their mouths, anomalies in the development of the aortic arch

Extravasal factors that contribute to compression of the vessel from the outside (additional cervical ribs, anterior scalene syndrome, etc.).

Clinical picture

Dizziness or lightheadedness (especially on exertion), possible blurred vision, hemianopia and ataxia

Muscle weakness in the limb on the side of the lesion

Absence or weakening of the pulse on the side of the lesion.

Diagnostics

Non-invasive measurement of blood pressure in the upper limbs (the difference in unilateral lesions reaches more than 20 mm Hg)

Differential Diagnosis

Subclavian artery occlusion

Occlusion of the subclavian artery is a complete closure of the lumen of the subclavian artery, accompanied by insufficient blood supply to the brain and upper limbs. In vascular surgery and cardiology, stenosis and occlusion of the carotid arteries are more common (54-57%). Occlusion of the first segment of the subclavian artery, according to different authors, is found in 3-20% of cases; while in 17% of cases there are concomitant lesions of the vertebral artery and/or the second segment of the subclavian artery. Bilateral occlusion of the subclavian artery occurs in 2% of cases; the second and third segments of the subclavian artery are affected much less frequently and have no independent significance in the pathogenesis of cerebrovascular ischemia. Occlusion of the left subclavian artery occurs 3 times more often than the right one.

The subclavian artery is a paired branch of the aortic arch, consisting of the right and left subclavian arteries that supply blood to the upper limbs and neck. The right subclavian artery originates from the brachiocephalic trunk, the left directly departs from the aortic arch. Topographically, 3 segments are distinguished in the subclavian artery. The vertebral artery departs from the first segment (supplies the spinal cord, muscles and dura mater of the occipital lobes of the brain), the internal thoracic artery (provides blood supply to the pericardium, main bronchi, trachea, diaphragm, sternum, anterior and superior mediastinum, pectoral muscles, rectus abdominis ) and the thyroid trunk (blood supply to the thyroid gland, esophagus, pharynx and larynx, muscles of the scapula and neck).

The only branch of the second segment of the subclavian artery (costal-cervical trunk) supplies blood to the muscles of the neck, cervical and beginning of the thoracic spine. The branch of the third segment (the transverse artery of the neck) mainly supplies blood to the muscles of the back.

Causes of subclavian artery occlusion

The main causes of subclavian artery occlusion are obliterating atherosclerosis. obliterating endarteritis. Takayasu's disease (nonspecific aortoarteritis), post-embolic and post-traumatic obliterations.

Atherosclerosis is the most common cause of occlusive lesions of the aorta and its branches. At the same time, atherosclerotic plaques protruding into the lumen of the vessel are formed in the intima of the arteries. As a result of subsequent sclerosis and calcification of the vascular wall in the area of the affected area, the deformation and stenosis of the vessel lumen gradually progress, which determine the ischemic stage of atherosclerosis. In some cases, atherosclerotic lesions can be complicated by thrombosis, leading to acute ischemia and necrosis of the blood-supplying organ (thrombo-necrotic stage of atherosclerosis). Additional risk factors for atherosclerosis are smoking, arterial hypertension. hypercholesterolemia. diabetes. cardiovascular disease.

Obliterating endarteritis, as the cause of occlusion of the subclavian artery, is characterized by inflammatory changes in the walls of the arteries, pronounced hyperplastic processes leading to thrombosis and obliteration of the vessels.

Takayasu's disease, named after a Japanese ophthalmologist. who first described it, can proceed with damage to the branches of the aortic arch, the development of aortic aneurysms. coarctation syndrome, aortic insufficiency. renovascular hypertension, abdominal ischemia, pulmonary artery disease, general inflammatory reaction. Nonspecific aortoarteritis most often leads to occlusion of the distal (second or third) segments of the subclavian arteries.

The development of occlusion of the subclavian artery can be facilitated by extravasal compression factors: scars and tumors of the mediastinum. curvature of the cervicothoracic spine, cervical osteochondrosis. neck injuries, fracture of the clavicle and 1st rib with the formation of excessive bone callus, chest trauma. In some cases, occlusion of the subclavian artery is the result of congenital anomalies of the aortic arch and its branches.

In the pathogenesis of disorders arising from occlusion of the subclavian artery, the main role belongs to ischemia of the tissues supplied by the affected branch. Thus, when the proximal segment of the subclavian artery is occluded, blood enters its distal segment and upper limb through the vertebral artery, which leads to depletion of the blood supply to the brain. This phenomenon, especially manifested during physical exertion, is called steel syndrome or "subclavian steal syndrome".

The rapid development of occlusion of the subclavian artery, associated with associated thrombosis, leads to cerebral ischemia - acute ischemic stroke.

Symptoms of subclavian artery occlusion

Occlusion of the first segment of the subclavian artery is manifested by one of the characteristic syndromes or their combination: vertebrobasilar insufficiency. upper limb ischemia, distal digital embolism, or coronary-mammary-subclavian steal syndrome.

Vertebrobasilar insufficiency with occlusion of the subclavian artery develops in approximately 66% of cases. The clinic of vertebrobasilar insufficiency is characterized by dizziness. headaches, cochleovestibular syndrome (hearing loss and vestibular ataxia), visual disturbances due to ischemic optic neuropathy.

Ischemia of the upper limb with occlusion of the subclavian artery is observed in approximately 55% of patients. During ischemia, 4 stages are distinguished:

I - stage of full compensation. Accompanied by increased sensitivity to cold, chilliness, numbness, paresthesia, vasomotor reactions. II - stage of partial compensation. Circulatory failure develops against the background of a functional load on the upper limbs. It is characterized by transient symptoms of ischemia - weakness, pain, numbness, coldness in the fingers, hand, muscles of the forearm. There may be transient signs of vertebrobasilar insufficiency. III - stage of decompensation. Circulatory failure of the upper extremities occurs at rest. It proceeds with constant numbness and coldness of the hands, muscle hypotrophy, a decrease in muscle strength, and the inability to perform fine movements with the fingers. IV - stage of development of ulcerative-necrotic changes in the upper limbs. There is cyanosis, swelling of the phalanges, cracks, trophic ulcers. necrosis and gangrene of the fingers.

Stage III and IV ischemia with occlusion of the subclavian artery is rarely detected (6-8% of cases), which is associated with a good development of the collateral circulation of the upper limb.

Distal digital embolism with occlusion of the subclavian artery of atherosclerotic origin, it occurs in no more than 3-5% of cases. In this case, ischemia of the fingers occurs, accompanied by severe pain, blanching, coldness and impaired sensitivity of the fingers, and occasionally gangrene.

In patients who have previously undergone mammary coronary bypass surgery. in 0.5% of cases may develop coronary-mammary-subclavian steal syndrome. In this case, hemodynamically significant stenosis or occlusion of the first segment of the subclavian artery can aggravate myocardial ischemia and cause myocardial infarction.

Diagnosis of occlusion of the subclavian artery

Occlusion of the subclavian artery can be suspected during the physical examination. With a difference in blood pressure in the upper limbs> 20 mm Hg. Art. should think of critical stenosis, and >40 mm Hg. Art. - about occlusion of the subclavian artery. The pulsation of the radial artery on the affected side is weakened or absent. With occlusion of the subclavian artery, a systolic murmur is heard in the supraclavicular region in 60% of patients.

Ultrasound or duplex scanning of the vessels of the upper limb helps to detect occlusion of the subclavian artery in 95% of cases. The criteria for occlusion of the first segment of the subclavian artery are the vertebral-subclavian steal syndrome, the presence of collateral blood flow in the distal subclavian artery, the presence of retrograde blood flow in the vertebral artery, and a positive reactive hyperemia test.

Peripheral arteriography allows you to finally determine the diagnosis of subclavian artery occlusion and treatment tactics. With the help of radiopaque angiography, the level of occlusion of the subclavian artery, retrograde blood flow through the vertebral arteries, the extent of obliteration, the presence of post-stenotic aneurysms, etc. are revealed.

Treatment and prognosis of subclavian artery occlusion

Subclavian artery occlusion, accompanied by subclavian-vertebral steal syndrome, symptoms of vertebrobasilar insufficiency, ischemia of the upper limb, is an indication for angiosurgical intervention.

Reconstructive interventions for occlusion of the subclavian artery are divided into:

plastic (endarterectomy, resection with prosthetics, implantation of the subclavian artery into the common carotid); shunting (aorto-subclavian bypass, carotid-subclavian bypass, carotid-axillary bypass, cross subclavian-subclavian bypass); endovascular (dilatation and stenting of the subclavian artery, laser or ultrasound recanalization of the subclavian artery).

Due to the high sensitivity of the brain to ischemia and the complexity of the anatomy of the neck, in the surgical treatment of occlusion of the subclavian artery, specific complications are possible - intraoperative or postoperative stroke; damage to peripheral nerves with the development of Horner's syndrome, plexitis, paresis of the dome of the diaphragm, dysphagia; cerebral edema, pneumothorax. lymphorrhea, bleeding.

The prognosis of occlusion of the subclavian artery depends on the nature and extent of the vessel lesion, as well as the timeliness of surgical intervention. Early surgery and good condition of the vessel wall is the key to restoring blood flow in the limb and vertebrobasilar basin in 96% of cases.

subclavian artery,a. subcldvia, originates from the aorta (left) and brachiocephalic trunk (right). The left subclavian artery is about 4 cm longer than the right. The subclavian artery exits the chest cavity through its upper aperture, goes around the dome of the pleura, enters (together with the brachial plexus) into the interstitial space, then passes under the clavicle, bends over 1 rib (lies in its groove of the same name) and below the lateral edge of this rib penetrates into axillary cavity, where it continues as the axillary artery.

Conventionally, the subclavian artery is divided into three sections: 1) from the place of origin to the inner edge of the anterior scalene muscle, 2) in the interstitial space and 3) at the exit from the interscalene space. In the first section, three branches depart from the artery: the vertebral and internal thoracic arteries, the thyroid-cervical trunk, in the second section - the costal-cervical trunk, and in the third - sometimes the transverse artery of the neck.

1. vertebral artery,a. vertebralis, - the most significant of the branches of the subclavian artery, departs from its upper semicircle at the level of the VII cervical vertebra. The vertebral artery has 4 parts: between the anterior scalene muscle and the long muscle of the neck is its prevertebral part, pars prevertebrdlis. Next, the vertebral artery goes to the VI cervical vertebra - this is its transverse process (cervical) part, pars transversdria (cervicalis), then passes upward through the transverse openings of the VI-II cervical vertebrae. Coming out of the transverse opening of the II cervical vertebra, the vertebral artery turns laterally and the next section is the atlas part, pars atldntica. Having passed through the hole in the transverse process of the atlas, it goes around its superior articular fossa [surface] behind, pierces the posterior atlanto-occipital membrane, and then the hard shell of the spinal cord (in the spinal canal) and through the large occipital foramen enters the cranial cavity - here its intracranial part begins , pars intracranidlis. Behind the pons of the brain, this artery joins with a similar artery on the opposite side, forming the basilar artery. From the second, transverse process, part of the vertebral artery depart spinal (radicular) branches,rr. spindles (radicals), penetrating through the intervertebral foramina to the spinal cord, and muscle branches,rr. muscles, to the deep muscles of the neck. All other branches are separated from the last - intracranial part: 1) anterior meningeal branch, d.meningeus an interior, and posterior meningeal branch, d.meningeus posterior[meningeal branches,rr. meningei]; 2) posterior spinal artery,a. spindlis posterior, goes around the outside of the medulla oblongata, and "then goes down along the posterior surface of the spinal cord, anastomosing with the artery of the same name on the opposite side; 3) anterior spinal artery,a. spindlis anteri or, connects with the artery of the same name of the opposite side into an unpaired vessel, heading down in the depths of the anterior fissure of the spinal cord; four) posterior inferior cerebellar artery(right and left), a. inferior posterior cerebelli, rounding the medulla oblongata, branches in the posterior inferior parts of the cerebellum.

basilar artery,a. basildris (see Fig. 47, 48), - an unpaired vessel, located in the basilar groove of the bridge. At the level of the anterior edge of the bridge, it is divided into two terminal branches - the posterior right and left cerebral arteries. From the trunk of the basilar artery depart: 1) anterior inferior cerebellar artery(right and left), a. inferior anterior cerebelli, branch on the lower surface of the cerebellum; 2) labyrinth artery(right and left), a. labyrinthi, pass near the vestibulocochlear nerve (VIII pair of cranial nerves) through the internal auditory meatus to the inner ear; 3) pontine arteries, aa.pontis (branches to the bridge); four) middle cerebral arteries, aa.mesenphdlicae (branches to midbrain); 5) superior cerebellar artery(right and left), a. superior cerebelli, branches in the upper parts of the cerebellum.

posterior cerebral artery,a. cerebri posterior, goes around the brain stem, branches on the lower surface of the temporal and occipital lobes of the cerebral hemisphere, gives off cortical and central branches. A flows into the posterior cerebral artery. cong-municans posterior (from the internal carotid artery), resulting in the formation arterial(willisian) brain circle,circulus arteriosus cerebri. The right and left posterior cerebral arteries, which close the arterial circle from behind, participate in its formation. -1 The posterior communicating artery connects the posterior cerebral artery with the internal carotid artery on each side. The front part of the arterial circle of the cerebrum is closed by the anterior communicating artery, located between the right and left anterior cerebral arteries, which branch off from the right and left internal carotid arteries, respectively. The arterial circle of the cerebrum is located on its base in the subnautonic space. It covers the front and sides of the optic chiasm; the posterior communicating arteries lie lateral to the hypothalamus, the posterior cerebral arteries are in front of the pons.

2. internal thoracic artery,a. thoracica interna (Fig. 49), departs from the lower semicircle of the subclavian artery opposite and somewhat lateral to the vertebral artery. The artery descends down the posterior surface of the anterior chest wall, adjoining the cartilages of the I-VIII ribs from behind. Under the lower edge of the VII rib, it splits into two terminal branches - the muscular-diaphragmatic and superior epigastric arteries. A number of branches depart from the internal mammary artery: 1) mediastinal branches,rr. mediastindles, to the mediastinal pleura and tissue of the upper and anterior mediastinum; 2) thymus branches,rr. thymici; 3) bronchial and tracheal branches,rr. bronchioles et tracheales, to the lower trachea and the main bronchus of the corresponding side; four) pericardial diaphragmatic artery,a. pericardiacophrenica, starts from the artery trunk at the level of the 1st rib and, together with the phrenic nerve, descends along the lateral surface of the pericardium (between it and the mediastinal pleura), gives branches to it and to the diaphragm, where it anastomoses with other arteries supplying the diaphragm; 5) chest branches,rr. sterndles, blood supply to the sternum and anastomosing with the same name branches of the opposite side; 6) perforating branches,rr. perfordntes, pass in the upper 5-6 intercostal spaces to the pectoralis major muscle, skin, and the 3rd, 4th and 5th perforating arteries give [medial] branches of the mammary gland, gg.mammarii [ mediates] (among women); 7) anterior intercostal branches,rr. intercostdles anteriores (I-V), depart in the upper five intercostal spaces in the lateral direction to the intercostal muscles; eight) musculophrenic artery, a.muscleophrenica, goes down and laterally to the diaphragm. Along the way, it gives intercostal branches to the muscles of the five lower intercostal spaces; 9) superior epigastric artery, a.epigastrica superior, enters the vagina of the rectus abdominis muscle, through its posterior wall, supplies blood to this muscle, located on its posterior surface. At the level of the navel, it anastomoses with the inferior epigastric artery (a branch of the external iliac artery). The musculophrenic and superior epigastric arteries are the terminal branches of the internal mammary artery.

3. thyroid trunk,truncus thyrocervicdlis, departs from the subclavian artery at the medial edge of the anterior scalene muscle. The trunk has a length of about 1.5 cm and in most cases is divided into 3 branches: the inferior thyroid, suprascapular and transverse arteries of the neck. 1) Inferior thyroid artery, a. thyroidea inferior, goes up the anterior surface of the long muscle of the neck to the thyroid gland and gives glandular branches,rr. glandular es. from the inferior thyroid artery pharyngeal and esophageal branches,rr. pharyngedles et oesophagedles; tracheal branches,rr. tracheales, and inferior laryngeal artery,a. laryngedlis inferior, which, under the plate of the thyroid cartilage, anastomoses with the superior laryngeal artery (a branch of the superior thyroid artery).

2) Suprascapular artery, a. suprascapuldris, behind the clavicle, it goes back to the notch of the scapula, through which it penetrates into the supraspinatus, and then into the infraspinatus fossa, to the muscles lying there. Anastomoses with the circumflex scapular artery (a branch of the subscapular artery) and gives acromial branch, d.acromidis, which anastomoses with the branch of the same name from the thoracoacromial artery.

3) Transverse artery of the neck, a. transversa cervicis, most often passes between the trunks of the brachial plexus posteriorly and at the level of the medial end of the spine of the scapula is divided into superficial branch,superficialis, next to the muscles of the back, and deep branch,profundus, which runs along the medial edge of the scapula down to the muscles and skin of the back. Both branches of the transverse artery of the neck anastomose with the branches of the occipital artery (from the external carotid artery), the posterior intercostal arteries (from the thoracic aorta), with the subscapular artery and the artery surrounding the scapula (from the axillary artery) (Table 2).

4. Costo-cervical trunk,truncus costocervicdlis, departs from the subclavian artery in the interstitial space, where it immediately divides into the deep cervical and highest intercostal arteries. 1) Deep cervical artery, a. cerviclidis profunda, follows posteriorly between the 1st rib and the transverse process of the 7th cervical vertebra, to the semispinous muscles of the head and neck. 2) The highest intercostal artery, a. inter- costlis suprema, goes down in front of the neck of the 1st rib and branches in the first two intercostal spaces, giving first and second posterior intercostal artery, aa.intercostdles posterio- res (I- II).

The subclavian artery is a paired organ consisting of the right and left subclavian arteries that supply blood to the arm and neck.

It is part of the systemic circulation and originates in the anterior mediastinum: the right subclavian artery comes from the brachiocephalic trunk, being its final branch, while the left one departs from the aortic arch. The left subclavian artery is longer than the right: its intrathoracic part lies behind the brachiocephalic vein.

The direction of the subclavian artery in relation to the upper aperture of the chest lies laterally and upwards, forming a slightly convex arc, enveloping the apex of the lung and the dome of the pleura.

Having reached the I rib, the subclavian artery enters the interstitial space, which is formed by the adjacent surfaces of the middle and anterior scalene muscles. In the specified interval on it is the brachial plexus.

Having rounded the 1st rib, the subclavian artery goes under the clavicle and enters the axillary cavity, where it is already called the axillary artery.

There are three main sections of the left and right subclavian arteries:

The first. It originates from the place of its formation to the entrance to the interstitial space;
Second. Begins in the interstitial space;
Third. It starts at the exit from the interstitial space up to the entrance to the axillary cavity.

The following branches of the subclavian artery depart from the first section:

Vertebral artery (a.vertebralis). Her path lies through the opening of the transverse process of the sixth cervical vertebra, rising up and entering the cranial cavity through the foramenmagnum - a large occipital foramen. Further, it connects with the artery on the other side, forming with it the basilar artery. The function of the vertebral artery is to supply blood to the spinal cord, muscles and dura mater of the brain (its occipital lobes);

The internal thoracic artery (a. thoracicainterna) originates from the lower surface of the subclavian artery. It supplies blood with nutrients dissolved in it to the thyroid gland, main bronchi, diaphragm, sternum, chest, tissue of the anterior and upper mediastinum, as well as the chest and rectus abdominis;
Thyrocervical trunk (truncusthyrocervicalis). It departs from the inner edge of the scalene muscle, reaching a length of about 1.5 cm, and is divided into several branches that supply blood to the mucous membrane of the larynx, neck muscles and scapula.

The second division of the subclavian artery has only one branch: the costocervical trunk (truncus costocervicalis). It originates on the posterior surface of the subclavian artery and is also divided into several branches: the deep cervical artery and the highest intercostal artery, from which the posterior (leading to the back muscles) and spinal branches depart.

The branch of the third division of the subclavian artery is the transverse artery of the neck, penetrating the brachial plexus and subdividing into the superficial artery, supplying blood to the muscles of the back, the deep branch of the subclavian artery and the dorsal artery of the scapula, which descends down to the wide back muscle, feeding it and the accompanying small muscles.

Subclavian artery lesions

Stenosis (narrowing of the lumen) is the main disease affecting the subclavian artery and its branches.

Stenoses, most often, are the result of atherosclerotic changes in the vessels or thrombosis. The causes of acquired (not congenital) stenosis of the subclavian artery are metabolic disorders in the body, inflammatory diseases and neoplasms.

Deposits on the walls of blood vessels that clog the artery have a lipid base, being, in fact, derivatives of cholesterol.

Narrowing or stenosis of the subclavian artery, which reduces about 80% of the lumen of the vessel, leads to a decrease in volumetric blood flow, which leads to a very negative effect - a lack of nutrients and oxygen by the tissues that are supplied with blood from the subclavian artery.

Arterial stenosis is often accompanied by the appearance of atherosclerotic plaques that can completely block the flow of blood in the artery and increase the likelihood of ischemic stroke.

The main complaint of patients with subclavian artery stenosis: pain, aggravated by physical exertion, mainly on the side of the affected limb.

Treatment

The main methods of treatment of stenosis of the subclavian arteries are:

X-ray endovascular stenting;
Carotid subclavian bypass.

Carotid-subclavian shunting is performed in patients with a hypersthenic constitution (in whom the isolation of 1 section of the subclavian artery is associated with certain difficulties), as well as when stenosis is detected in the second section of the subclavian artery.

X-ray endovascular stenting has great advantages over open surgery: the operation is performed under local anesthesia through a small (2-3 mm) skin incision through the puncture hole.

Subclavian artery (a. subclavia) - a large paired vessel, is part of the subclavian neurovascular bundle of the neck, which is formed by the subclavian artery, subclavian vein and brachial plexus.

The right subclavian artery departs from the brachiocephalic trunk (truncus brachiocephalicus), the left - directly from the aortic arch (arcus aortae), so the left one is 4 cm longer than the right one. Three sections are distinguished along the course of the subclavian artery and according to its relationship with the anterior scalene muscle.

On its way, the subclavian artery passes along with the brachial plexus through the spatium interscalenum, formed by the adjacent surfaces of the anterior and middle scalene muscles, and passes along the 1st rib into sulcus a. subclaviae. Therefore, 3 sections are topographically distinguished in the subclavian artery: the first section - from the place of origin of the artery to the inner edge of the anterior scalene muscle (m. scalenus ant.) in the scale-vertebral gap (spatium scalenovertebrale), the second - limited by the limits of the interscalene gap (spatium interscalenum) and the third - from the outer edge of the anterior scalene muscle to the middle of the clavicle, where the subclavian artery passes into the axillary (a. axillaris). In the third section, the subclavian artery can be pressed against the I rib behind tuberculum m to stop bleeding. scaleni.

The 1st subclavian artery gives three important branches:

vertebral (a. vertebralis), thyroid trunk (truncus thyrocervicalis), internal thoracic artery (a. thoracica interna). As well as branches from the thyroid trunk (truncus thyreocervicalis): the lower thyroid artery (a. thyroidea inferior), and its branch - the ascending cervical artery (a. cervicalis ascendens), superficial cervical artery (a. cervicalis superficialis), suprascapular artery (a. suprascapularis). The suprascapular artery (a. suprascapularis) is involved in the formation of the scapular arterial circle.

The 2nd division of the subclavian artery gives branches: the costocervical trunk (truncus costocervicalis) and its branches: the uppermost intercostal artery (a. intercostalis suprema), and the deep cervical artery (a. cervicalis profunda), penetrating into the muscles of the back of the neck.

The third section of the subclavian artery is located in the outer triangle of the neck, here the transverse artery of the neck (a. transversa colli) departs from the artery, which perforates the plexus brachialis, supplies neighboring muscles and descends along the medial edge of the scapula to its lower angle. All elements of the subclavian neurovascular bundle are connected together to pass into the axillary fossa on the upper limb.

Shoulder plexus.

The brachial plexus, plexus brachialis, is composed of the anterior branches of the four lower cervical nerves and most of the first thoracic; often a thin branch from C111 joins. The brachial plexus exits through the gap between the anterior and middle scalene muscles into the supraclavicular fossa, located above and behind a. subclavia. Three thick nerve bundles arise from it, going into the axillary fossa and surrounding a. axillaris from three sides: from the lateral (lateral bundle), medial (medial bundle) and posterior to the artery (posterior bundle). In the plexus, the supraclavicular (pars supraclavicularis) and subclavian (pars infraclavicularis) parts are usually distinguished. Peripheral branches are divided into short and long. Short branches depart in various places of the plexus in its supraclavicular part and partly supply the muscles of the neck, as well as the muscles of the girdle of the upper limb (with the exception of m. trapezius) and the shoulder joint. Long branches originate from the above three bundles and run along the upper limb, innervating its muscles and skin. Projection of the brachial plexus: the patient's head is turned in the opposite direction from the surgeon and is taken up. The projection corresponds to the line connecting the border between the middle and lower thirds of the posterior edge of the sternocleidomastoid muscle with the middle of the upper edge of the clavicle.

Ticket 78

1. Topography of the outer triangle of the neck: boundaries, external landmarks, layers, fascia and cellular spaces, vessels and nerves. 2. Scapular-clavicular triangle. 3. Vascular - nerve bundle of the outer triangle. 4. Scapular - trapezoid triangle. 5. Vascular - nerve formations. 6. Projection on the skin of the subclavian artery, operative access to the artery according to Petrovsky.

1. Topography of the outer triangle of the neck: boundaries, external landmarks, layers, fascia and cellular spaces, vessels and nerves.

Borders: in front of the lateral (rear) edge m. sternocleidomastoideus, behind - the anterior edge of the trapezius muscle (musculus trapezius), below - the clavicle (clavicula).

By the lower abdomen, the scapular-hyoid muscle (m. omohyoideus) divides the lateral region into two triangles: the larger scapular-trapezoid triangle (trigonum omotrapezoideum) and the smaller scapular-clavicular triangle (trigonum omoclaviculare).

External landmarks that form the boundaries of the area. An important landmark is the posterior edge of the sternocleidomastoid muscle, m. sternocleidornastoideus, clearly visible, especially when turning the head in the opposite direction, as well as the anterior edge of the trapezius muscle - the back. The clavicle limits the area from below.

2. Scapular-clavicular triangle (trigonum omoclaviculare).

Borders: triangle, the lower border is the clavicle, the front is the posterior edge of the sternocleidomastoid muscle, the upper-posterior border is the projection line of the lower abdomen of the scapular-hyoid muscle (m. omohyoideus).

External landmarks: large supraclavicular fossa, fossa supraclavicularis major.

Layers and fasciae: Skin, subcutaneous fat, fascia. The skin of the scapular-clavicular triangle is thin and mobile. The superficial fascia and platysma of the scapular-clavicular triangle cover the entire triangle, as does the superficial lamina of the fascia of the neck (2nd fascia). Between the 1st and 2nd fascia in the lower part of the scapular-clavicular triangle, along the posterior edge of the sternocleidomastoid muscle, passes v. jugularis externa. It perforates the 2nd and 3rd fascia and flows into the confluence angle of the subclavian and internal jugular veins or the common trunk with the internal jugular vein into the subclavian. The adventitia of the vein is associated with the fascia that it perforates, so it gapes when injured. In this case, along with heavy bleeding, an air embolism is also possible. The pretracheal plate of the fascia of the neck (3rd fascia) is located below m. omohyoideus, behind the 2nd fascia of the neck. Together with her, she is attached to the collarbone. Behind the 3rd fascia in the scapular-clavicular triangle is an abundant layer of fatty tissue containing the supraclavicular lymph nodes. There is no 4th fascia in this scapular-clavicular triangle. The 5th fascia is prevertebral, poorly developed and forms a sheath for the neurovascular bundle.

TOTAL FASCIA IN THE BULDOCLAVIC TRIANGLE: 1, 2, 3, X, 5.

Cell gap: cellular space of the scapular-clavicular triangle (spatium omoclaviculare) .

3. Vascular - nerve bundle of the scapular - clavicular triangle

Between the 3rd and the 5th fascia lying behind it, the subclavian vein passes, heading from the middle of the clavicle to the prescalene space. In it, between the 1st rib and the clavicle, the walls of the subclavian vein are firmly fused with the fascial sheath of the subclavian muscle and the fasciae of the neck. Thanks to its fixed position, the subclavian vein is available here for punctures and percutaneous catheterization. Sometimes, with sudden movements of the arm during heavy physical exertion, the subclavian vein can be compressed between the clavicle and the subclavian muscle and the 1st rib, followed by the development of acute thrombosis of both the subclavian and axillary veins (Paget-Schretter syndrome). Clinical manifestations of the syndrome are edema and cyanosis of the limb. A pronounced pattern of veins is determined on the shoulder and anterior surface of the chest.

In the scapular-clavicular triangle, under the 5th fascia, partly above the clavicle, there are 3 arteries: a. suprascapularis, a. cervicalis superficialis and a. transversa colli, moreover, the superficial cervical and suprascapular arteries run behind the upper edge of the clavicle anteriorly and below the trunks of the supraclavicular part of the brachial plexus plexus brachialis, and the transverse artery of the neck passes between the trunks of this plexus. The subclavian artery and the brachial plexus pass into the scapular-clavicular triangle from the interstitial space. The 5th fascia forms the sheath for the brachial plexus and artery. The subclavian artery (3rd section) lies on the 1st rib immediately outward from the scalene tubercle and descends down the anterior surface of the 1st rib, thus being located between the clavicle and the 1st rib. In the third section a. subclavia can be pressed to stop bleeding to the 1st rib behind tuberculum m. scaleni.

Projections. The subclavian artery projects to the middle of the clavicle. The subclavian vein is projected medially to the artery, the projection line of the brachial plexus runs from above the border between the lower and middle thirds of the sternocleidomastoid muscle at an angle to the clavicle lateral to the artery.

4. Scapular - trapezoid triangle (trigonum omotrapezoideum)

Borders: from below it limits the scapular-hyoid muscle (m. omohyoideus), in front - the posterior edge of the sternocleidomastoid muscle, behind - the anterior edge of the trapezius muscle.

External landmarks: the anterior edge of the trapezius and the posterior edge of the sternocleidomastoid above the greater supraclavicular fossa.

Layers and 5. Vascular - nerve formations.

The skin is thin, mobile. In the subcutaneous tissue of the triangle there are branches of the cervical plexus - supraclavicular nerves, nn. supraclaviculares, innervating the skin of the neck and shoulder girdle.

The superficial fascia covers the entire triangle. Flatysma covers only the anteroinferior part of the triangle. The next layer, as in all other triangles, is the superficial plate of the fascia of the neck (2nd fascia). Neither the 3rd nor the 4th fascia is present in this triangle.

In the fiber between the 2nd and 5th fascia passes the accessory nerve, n. accessorius, which innervates the sternocleidomastoid and trapezius muscles.

From under the sternocleidomastoid muscle, there are also transverse superficial cervical arteries and veins. These vessels, as well as the accessory nerve, lie on the 5th fascia. In the same layer, along the accessory nerve, there are lymph nodes that collect lymph from the tissues of the lateral region of the neck.

The 5th, prevertebral, fascia covers the anterior and middle scalene muscles. Between these muscles, the cervical and brachial plexuses, plexus cervicalis and plexus brachialis, also lying under the 5th fascia, are formed.

TOTAL FASCIA IN THE SHOULDER-TRAPEZIOID TRIANGLE: 1, 2, X, X, 5.