Humerus structure anatomy. Anatomy: Humerus

The shoulder joint is a movable connection of the humerus with the upper shoulder girdle, which includes the clavicle and scapula. The humerus is part of the upper limb. This is a tubular long bone, which is an important anatomical structure, since most of the muscles that set the upper limb in motion are attached to it. In the proximal part of this bone is the so-called head, which is part of shoulder joint, thereby connecting the upper limb to the shoulder girdle (in particular, to the shoulder blade). The anatomical feature of the head of the humerus, which is part of the joint, allows the upper limb to move in different directions and in different ranges, thereby providing it with multifunctionality.

In the process of evolution, the forelimbs have lost their supporting function. As a result, primates stood on their hind legs, freeing their forelimbs for work and development. As a result of this process, the bones of the upper limbs became smaller and lighter than the bones lower extremities.

Anatomical structure

The structure of the human shoulder joint presents a certain complexity. It consists of two main elements:

• shoulder blades;
• brachial bone;

shoulder blade- a flat bone that has the shape of a triangle. It is located on the back side of the body, that is, on the back. The shoulder blade has three edges:

• upper;
• medial;
• lateral.

The last edge - the lateral one is particularly thick and massive, and also includes an articular cavity in its upper part, which is necessary to connect the head of the shoulder bone. This cavity is provided with the neck of the scapula, and immediately above the cavity there are two tubercles: subarticular and supraarticular. The scapular surface on the side of the rib is slightly concave, facing the chest and is a subscapular cavity. The dorsal surface of the scapula is convex. You can touch it if you put your hands behind your back and feel for the most convex part of your back. The back surface has two muscles.

The clavicle is part of the shoulder girdle. This is a tubular bone that has a curved shape in the form of an elongated letter S. It is the only bone that connects the upper limb to the skeleton of the body. Its functionality lies in the fact that it supports at a certain distance the scapular-shoulder joint from the body. Thus, increasing the motor activity of the upper limb. The clavicle can be easily felt under the skin. It is attached to the sternum and shoulder blade with ligaments.

The humerus is a tubular bone that has a special anatomical structure due to muscle attachment.

It consists of two epiphyses (upper and lower) and a diaphysis located between them. The upper epiphysis consists of a head that enters the joint. The transition from this head to the body of the bone or diaphysis is called the anatomical neck or metaphysis. Outside of the neck there are two tubercles to which the muscles are attached.

The body of the bone has a trihedral shape. Its head is spherical, turned towards the shoulder blade and enters the shoulder joint.

The large and small tubercle is turned outward and inward, respectively. A ridge departs from the hillocks, and there is a furrow between them. The tendon of the head of the muscle passes through it. Also there is a surgical neck, the narrowest place of the shoulder, located below the tubercles.

The shoulder joint is formed by the head of the shoulder and the articular scapular cavity. It has the shape of a hemisphere. The spherical shape of the surface determines the circular movements of the hand, since the movements in the shoulder joint are often identified with the movements of the hands. It is for this reason that the outstretched arm is able to describe a hemisphere in the air, that is, it is retracted forward and to the side only by 90 °. The shoulder joint has a smaller span. To raise your arm up, you need to involve the collarbone and scapula in the work.

This joint is the most mobile, therefore it is subjected to heavy loads and is often injured. This is also due to the fact that the joint capsule is very thin, and the movements made by the joint have a large amplitude.

The shoulder joint is located between humerus And radius forearm. The acromio-clavicular joint connects the clavicle to the acromial process of the scapula. Its articular surface is covered with cartilaginous and fibrous tissue. The acromion process can be palpated by finding a firm bulge on the back of the shoulder.

Injuries and damage

Due to its excessive physical activity, the humerus is subject to many injuries and damage. These include the following injuries and fractures:

Dislocation

It develops as a result of indirect injuries, that is, when falling on an outstretched arm or elbow, as well as with direct injuries, when a blow is applied to the shoulder.

Dislocations are characterized by displacement of the head of the bone forward. Anterior dislocations are the most common. Trauma is characterized severe pain, swelling, hemorrhage and limitation of mobility. With posterior dislocations, the same symptoms are observed as with anterior ones. Dislocations may be accompanied by other injuries. For example, it may break large tubercle or fracture of the surgical neck. In this case, it is necessary to check the sensitivity of the hand and arm.

You can not set the dislocation at the scene. Moreover, this can not be done to people without special medical education. It is necessary to provide first medical care and then transport the patient to a medical facility. First aid consists in fixing the shoulder with a special soft bandage in the form of a scarf. Dislocations are reduced only in medical institution And only under anesthesia.

Humerus fractures can occur in several places:

Fractures of the diaphysis

Occurs due to a direct blow to the bone, as well as when falling on the elbow. At the same time, deformation of the shoulder and its shortening and immobility, pain, crepitus, edema, hematomas and pathological mobility are observed. When providing first aid, put a splint on the damaged area and give the victim painkillers. Such fractures in the lower and middle third are treated with skeletal traction, and with the help of a splint, injuries in the upper third of the shoulder are treated.

Fractures of the anatomical neck of the bone

Occur due to a fall on the elbow or a direct blow. With neck injuries, fragments are pressed into the head of the bone. As a result, the head is able to deform, come off and shatter.

It is manifested by swelling, pain and hematoma. The functionality of the limb is severely limited. A fracture of the anatomical neck can be impacted, then the symptoms are not so acute, and the person is able to move his hand.

Treatment can be either inpatient or outpatient. In both cases, a plaster splint is applied to accurately fix the shoulder in the correct physiological position. Prescribe analgesics and sedatives. After removing the splint, wearing a bandage such as a scarf is prescribed, as well as massage and phytotherapeutic procedures for the speedy recovery of the shoulder and limb. Fully recovery occurs after 2-2.5 months.

Distal fractures

Such injuries are called extra-articular. They are flexion and extensor, depending on the injury received in the fall. Intra-articular - are injuries of the head of the condyle. Manifested painful sensations, crepitus, pathological mobility. When providing first aid, the limb is immobilized using a scarf bandage. Painkillers are also administered.

Fractures of the surgical neck

Injuries to the surgical neck are impacted or hammered together. A displaced fracture can be abducting and externally displaced, and an angle is formed between the bone fragments. Such damage is called adduction. It occurs when falling on an outstretched hand. If at the moment of injury the shoulder was abducted, and its central end shifted inward, it is called abduction. When providing first aid, analgesics are administered, a splint is applied and the victim is transported to a medical facility.

Tubercles fractures

As a rule, tubercle injuries are dislocations. In this case, the tubercle is displaced and comes off due to reflex muscle contraction. With an isolated fracture of the tubercle, displacement is not observed. In this case, pain, crepitus, edema, and pathological mobility occur. First aid is to apply a Dezo bandage to fix the collarbone to the body, you can also use a soft bandage or scarf. The bandage is worn for approximately one month. If within a month there is a hemorrhage into the joint cavity (hemarthrosis) and swelling, then shoulder traction is prescribed for 15 days. The recovery period lasts one month.

The shoulder refers to the long tubular bones of a person. Anatomy is simple and is determined by a number of functions performed. On its surface there are anatomical formations, such as the head, medial condyle, as well as tubercles and fossae, which serve as attachment points for muscles and ligaments. The humerus acts as a lever. Fractures are very dangerous, because due to damage to the bone marrow canal, a fat embolism may develop or a blockage of the vessel may occur.

Most often, the shoulder suffers as a result of fractures in the anatomical neck.

Structure and anatomy

At the top of the bone there is a round formation - the head, which is an integral part of the joint. It is separated from the rest of the bone by a narrow groove. It is called the anatomical neck. It is in this part that fractures most often occur. Behind it is the place of attachment of the main muscles of the shoulder, represented by two tubercles - large and small, as well as ridges. The small tubercle is located in front on the shoulder. There is a tuberosity in the middle of the bone. This is where the deltoid muscle attaches. From the side of the elbow, the humerus ends with 2 epicondyles, between which there is an articular surface. The medial condyle is much larger than the lateral one. There are also 2 recesses - the olecranon or cubital fossa and the radius.

Functions of the humerus

The shoulder structure is actually a lever and increases the scope when performing movements of the upper limb. In addition, the bone is involved in maintaining balance when the center of gravity shifts during walking. This element determines the correct support of a person on his hands when climbing stairs and in other specific body positions.

Damage: causes and symptoms

dislocation of the shoulder and elbow joint occurs frequently, and is associated with great mobility of the upper limb. Distinguish front, rear and bottom offset. In case of damage, movement of the limb becomes difficult, pain is felt, swelling is visualized. When a nerve is pinched, the skin becomes numb. Dislocations are isolated as new and chronic. At the same time, a large tubercle protrusion or a neck fracture may occur. The shoulder is swollen, it hurts, hemorrhage is noticeable, sensitivity is lost in the arm and fingers.

A fracture of the humerus occurs due to a significant force impact. This happens when you fall back on your elbows or forward on outstretched arms. The splitting of bones occurs in anatomically weak places. These include:

• anatomical and surgical neck;
• area of ​​condyles;
• region of the head of the humerus;
• the middle of the bone.

Immediately after the injury, the patient feels a sharp pain in the arm, as well as the inability to perform actions with it. The exact amount of lost movements depends on the immediate location of the damage. After some time, there is a strong swelling of the shoulder, bruising and bruising is possible. In this case, the limb is significantly deformed.

Diseases

A common disease is, that is, the introduction of infection into the bone marrow through the blood. The shoulder is affected because this bone is tubular and has an abundant blood supply. As a result of the development of this disease, the bone tissue can decompose, and then pathological fractures are formed (without the participation of a strong external influence). In addition, the development of arthritis of the shoulder and elbow joint is possible.

The shoulder joint (articulatio humeri) is the largest and most mobile articulation of the upper limb, allowing you to make a variety of hand movements. This amplitude is provided by the special structure of the shoulder joint. It is located in the proximal parts of the upper limb, connecting it with the trunk. In a thin person, his contours are clearly visible.

The device articulatio humeri is quite complex. Each element in the articulation accurately performs its functions, and even a slight pathology of any of them leads to changes in the rest of the structure. Like other joints of the body, it is formed by bone elements, cartilaginous surfaces, a ligamentous apparatus and a group of adjacent muscles that provide movement in it.

What bones form the shoulder joint

Articulatio humeri is a simple ball-and-socket articulation. The humerus and scapula, which is part of the upper shoulder girdle, participate in its formation. The articular surfaces covering the bone tissue are formed by the scapular cavity and the head of the humerus, which is several times larger than the cavity. This discrepancy in size is corrected by a special cartilaginous plate - the articular lip, which completely repeats the shape of the scapular cavity.

Ligaments and capsule

The articular capsule is attached around the circumference of the cavity of the scapula on the border of the cartilaginous lip. It has a different thickness, quite free and spacious. Inside is synovial fluid. The front surface of the capsule is the thinnest, so it is quite easily damaged in case of dislocation.

Tendons attached to the surface of the capsule pull it back during hand movements and prevent it from being pinched between the bones. Some of the ligaments are partially woven into the capsule, strengthening it, while others prevent excessive extension when making movements in the upper limb.

Synovial bags (bursae) articulatio humeri reduce friction between individual articular elements. Their number may vary. Inflammation of such a bag is called bursitis.

The most permanent bags include the following types:

• subscapular;
• subcoracoid;
• intertubercular;
• subdeltoid.

Muscles play a key role in strengthening the shoulder joint and making various movements in it. The following movements are possible in the shoulder joint:

• adduction and abduction of the upper limb in relation to the body;
• circular, or rotational;
• turning the arm inward, outward;
• raising the upper limb in front of you and taking it back;
• institution of the upper limb behind the back (retroflexion).

The area of ​​articulatio humeri is predominantly supplied with blood from the axillary artery. Smaller arterial vessels depart from it, forming two vascular circles - scapular and acromio-deltoid. In the event of a blockage of the main artery, the periarticular muscles and the shoulder joint itself receive nutrition precisely thanks to the vessels of these circles. The innervation of the shoulder is carried out due to the nerves that form the brachial plexus.

The rotator cuff is a complex of muscles and ligaments that, in total, stabilize the position of the head of the humerus, are involved in turning the shoulder, in lifting and flexing the upper limb.

The following four muscles and their tendons are involved in the formation of the rotator cuff:

• supraspinatus,
• infraspinatus,
• subscapular,
• small round.

The rotator cuff slides between the head of the shoulder and the acromion (articular process) of the scapula during raising the arm. A bursa is placed between these two surfaces to reduce friction.

In some situations, with frequent upward movements of the hand, it can occur. In this case, it often develops. It is manifested by a sharp pain that occurs when trying to get an object out of the back pocket of your trousers.

Microanatomy of the shoulder joint

The articular surfaces of the scapular cavity and the head of the shoulder are covered with hyaline cartilage from the outside. Normally, it is smooth, which contributes to the sliding of these surfaces relative to each other. At the microscopic level, the collagen fibers of cartilage are arranged in arches. This structure contributes to the uniform distribution of intra-articular pressure that occurs when the upper limb moves.

The joint capsule, like a pouch, hermetically covers these two bones. Outside, it is covered with a dense fibrous layer. It is additionally strengthened by interwoven tendon fibers. Small vessels and nerve fibers pass through the surface layer of the capsule. The inner layer of the joint capsule is represented by the synovial membrane. Synovial cells (synoviocytes) are of two types: phagocytic (macrophage) - they clean the intra-articular cavity from decay products; secretory - produce synovial fluid (synovia).

The consistency of synovial fluid is similar to egg white, it is sticky and transparent. The most important component of synovium is hyaluronic acid. Synovial fluid acts as a lubricant for the articular surfaces and also provides nutrition. outer surface cartilage. Its excess is absorbed into the vasculature of the synovial membrane.

Lack of lubrication leads to rapid wear of the articular surfaces and.

The structure of the human shoulder joint in pathology

Congenital dislocation and subluxation of the shoulder is the most severe abnormal development of this joint. They are formed due to the underdevelopment of the head of the humerus and processes of the scapula, as well as the muscles surrounding the shoulder joint. In the case of subluxation, the head, when the muscles of the shoulder girdle are tense, is independently reduced and takes a position close to the physiological one. Then it returns to its usual, anomalous position again.

Underdevelopment individual groups muscles (hypoplasia), involved in the movements of the joint, leads to a limitation of the range of motion in it. For example, a child cannot raise his arm above the shoulder, with difficulty putting it behind his back.

On the contrary, with articulatio humeri dysplasia, which occurs as a result of anomalies in the formation of the tendon-ligamentous apparatus of the joint, hypermobility develops (an increase in the range of motion in the joint). This condition is fraught with habitual dislocations and subluxations of the shoulder.
With arthrosis and arthritis, there is a violation of the structure of the articular surfaces, their ulceration, bone growths (osteophytes) are formed.

X-ray anatomy of the shoulder joint in normal and pathological conditions

On a radiograph, articulatio humeri looks like the picture below.

The numbers in the figure indicate:

1. Collarbone.
2. Acromion of the scapula.
3. Large tubercle of the humerus.
4. Lesser tubercle of the humerus.
5. Shoulder neck.
6. Brachial bone.
7. Coracoid process of the scapula.
8. The outer edge of the scapula.
9. Edge.

The arrow without a number indicates the joint space.

In the case of dislocation, inflammatory and degenerative processes, there is a change in the ratio of various structural elements of the joint to each other, their location. Special attention pay attention to the position of the head of the bone, the width of the intra-articular gap.
The photo of the radiographs below shows a dislocation and arthrosis of the shoulder.

Features of the shoulder joint in children

In children, this joint does not immediately take the same shape as in adults. At first, the large and small tubercles of the humerus are represented by separate ossification nuclei, which subsequently merge and form a bone of the usual type. The joint is also strengthened due to the growth of ligaments and shortening of the distance between the bone elements.

Due to the fact that articulatio humeri is more vulnerable in young children than in adults, dislocations of the shoulder are periodically observed. They usually occur if an adult pulls the child's hand up sharply.

Some interesting facts about the device articulatio humeri

The special structure of the shoulder joint and its constituent parts have a number of interesting features.

Does the shoulder move silently?

Compared to other joints in the body, such as the knee, finger joints, and spine, the articulatio humeri operates almost silently. In fact, this is a false impression: articular surfaces rubbing against each other, sliding muscles, stretching and contracting tendons - all this creates a certain level of noise. However, the human ear distinguishes it only when organic changes are formed in the structure of the joint.

Sometimes with jerky movements, for example, when the child is pulled sharply by the arm, you can hear popping sounds in the shoulder. Their appearance is explained by the short-term occurrence in the articulation cavity of the area low pressure due to physical forces. At the same time, gases dissolved in the synovial fluid, for example, carbon dioxide, rush into the area of ​​​​low pressure, turn into a gaseous form, forming bubbles. However, then the pressure in the joint cavity quickly normalizes, and the bubbles “burst”, making a characteristic sound.

In a child, a crunch during movements in the shoulder may occur during periods of increased growth. This is due to the fact that all the articular elements of the articulation articulatio humeri grow with different speed, and their temporary discrepancy in size also begins to be accompanied by a "crack".

Arms are longer in the morning than in the evening

The articular structures of the body are elastic and resilient. However, during the day under the action physical activity and weight own body the joints of the spine and lower extremities sag somewhat. This leads to a decrease in height by about 1 cm. But articular cartilage shoulders, forearms and hands do not experience such a load, therefore, against the background of reduced growth, they seem a little longer. During the night, the cartilage is restored and growth becomes the same.

proprioception

Part of the nerve fibers that innervate the structures of the joint, thanks to special "sensors" (receptors), collects information about the position of the upper limb and the joint itself in space. These receptors are located in the muscles, ligaments, and tendons of the shoulder joint.

They react and send electrical impulses to the brain, if the position of the joint in space changes with the movements of the arm, its capsule, ligaments are stretched, and the muscles of the upper shoulder girdle contract. Thanks to such a complex innervation, a person can almost automatically make many precise hand movements in space.

The hand itself “knows” to which level it needs to rise, which turn to make in order to take some object, straighten clothes and perform other mechanical actions. Interestingly, in such mobile joints as articulatio humeri, there are highly specialized receptors that transmit information to the brain only for rotation in the cuff of the joint, adduction, abduction of the upper limb, etc.

Conclusion

The structure of the shoulder joint allows for an optimal range of motion of the upper limb that meets physiological needs. However, with weakness of the ligamentous apparatus of the shoulder and in childhood dislocations and subluxations of the head of the humerus can be observed relatively often.

The shoulder is the proximal (closest to the body) segment of the upper limb. The upper border of the shoulder is a line connecting the lower edges of the pectoralis major and broad back muscles; lower - a horizontal line passing over the condyles of the shoulder. Two vertical lines drawn upward from the condyles of the shoulder conventionally divide the shoulder into anterior and posterior surfaces.

On the anterior surface of the shoulder, external and internal furrows are visible. The bone base of the shoulder is the humerus (Fig. 1). Numerous muscles are attached to it (Fig. 3).

Rice. 1. Humerus: 1 - head; 2 - anatomical neck; 3 - small tubercle; 4 - surgical neck; 5 and 6 - crest of small and large tubercle; 7 - coronal fossa; 8 and 11 - internal and external epicondyle; 9 - block; 10 - capitate elevation of the humerus; 12 - radial fossa; 13 - furrow radial nerve;14 - deltoid tuberosity; 15 - large tubercle; 16 - groove of the ulnar nerve; 17 - cubital fossa.

Rice. 2. Fascial sheaths of the shoulder: 1 - sheath of the beak-brachial muscle; 2-beam nerve; 3 - musculocutaneous nerve; 4 - median nerve; 5 - ulnar nerve; 6 - vagina of the triceps muscle of the shoulder; 7 - sheath of the shoulder muscle; 8 - sheath of the biceps muscle of the shoulder. Rice. 3. Places of origin and attachment of muscles on the humerus, right in front (i), behind (b) and on the side (c): 1 - supraspinatus; 2 - subscapular; 3 - wide (back); 4 - large round; 5 - beak-shoulder; 6 - shoulder; 7 - round, rotating the palm inward; 8 - radial flexor of the hand, superficial flexor of the hand, long palmar; 9 - short radial extensor of the hand; 10 - long radial extensor of the hand; 11 - shoulder-radial; 12 - deltoid; 13 - large sternum; 14 - infraspinatus; 15 - small round; 16 and 17 - the triceps muscle of the shoulder (16 - lateral, 17 - medial head); 18 - muscles that rotate the palm outward; 19 - elbow; 20 - extensor of the thumb; 21 - extensor of the fingers.

The muscles of the shoulder are divided into 2 groups: the anterior group is made up of flexors - the biceps, shoulder, coracobrachial muscles, the back group is the triceps muscle, extensor. The brachial artery, which goes under, accompanied by two veins and the median nerve, is located in the internal groove of the shoulder. The projection line of the artery on the skin of the shoulder is drawn from the deepest point to the middle of the cubital fossa. The radial nerve passes through the canal formed by the bone and the triceps muscle. The ulnar nerve goes around the medial epicondyle, located in the sulcus of the same name (Fig. 2).

Closed shoulder injury. Fractures of the head and anatomical neck of the humerus - intra-articular. Without them, it is not always possible to distinguish from, perhaps a combination of these fractures with dislocation.

A fracture of the tubercles of the humerus is recognized only radiographically. A fracture of the diaphysis is usually diagnosed without difficulty, but is required to determine the shape of the fragments and the nature of their displacement. A supracondylar fracture of the shoulder is often complex, T-shaped or V-shaped, so that the peripheral fragment is divided in two, which can only be recognized on the picture. Possible and simultaneous dislocation of the elbow.

With a diaphyseal fracture of the shoulder, the traction of the deltoid muscle displaces the central fragment, taking it away from the body. The displacement is greater the closer to the broken bone. In case of a fracture of the surgical neck, the peripheral fragment is often driven into the central one, which is determined on the picture and most favors the union of the fracture. With a supracondylar fracture, the triceps muscle pulls the peripheral fragment from the back and up, and the central fragment moves forward and down (to the cubital fossa), while it can compress and even injure the brachial artery.

First aid for closed fractures of the shoulder comes down to immobilizing the limb with a wire splint from the shoulder blade to the hand (the elbow is bent at a right angle) and fixing it to the body. If the diaphysis is broken and there is a sharp deformity, you should try to eliminate it by careful traction on the elbow and bent forearm. With low (supracondylar) and high fractures of the shoulder, reduction attempts are dangerous; in the first case, they threaten to damage the artery, in the second, they can disrupt the impaction, if any. After immobilization, the victim is urgently sent to a trauma facility for X-ray examination, reposition and further inpatient treatment. It is carried out, depending on the characteristics of the fracture, either in a plaster thoraco-brachial bandage, or by traction (see) on the outlet splint. With an impacted fracture of the neck, none of this is required; the hand is fixed to the body with a soft bandage, placing a roller under the arm, and after a few days, therapeutic exercises begin. Uncomplicated closed fractures of the shoulder heal in 8-12 weeks.

Shoulder diseases. From purulent processes acute hematogenous osteomyelitis is most important (see). After an injury, a muscle hernia may develop, more often a hernia of the biceps muscle (see Muscles, pathology). Of the malignant neoplasms, there are those forcing the amputation of the shoulder.

Shoulder (brachium) - the proximal segment of the upper limb. Upper bound shoulder - a line connecting the lower edges of the pectoralis major and broad dorsal muscles, the lower one - a line passing two transverse fingers above the condyles of the humerus.

Anatomy. The skin of the shoulder is easily mobile, it is loosely connected to the underlying tissues. On the skin of the lateral surfaces of the shoulder, internal and external grooves (sulcus bicipitalis medialis et lateralis) are visible, separating the anterior and posterior muscle groups. Own fascia of the shoulder (fascia brachii) forms a vagina for muscles and neurovascular bundles. From the fascia deep into the humerus, the medial and lateral intermuscular septa (septum intermusculare laterale et mediale) depart, forming the anterior and posterior muscle containers, or bed. In the anterior muscle bed there are two muscles - the biceps and the shoulder (m. Biceps brachii et m. brachialis), in the back - the triceps (m. triceps). In the upper third of the shoulder there is a bed for the coracobrachial and deltoid muscles (m. coracobrachialis et m. deltoideus), and in the lower third there is a bed for the shoulder muscle (m. brachialis). Under the own fascia of the shoulder, in addition to the muscles, there is also the main neurovascular bundle of the limb (Fig. 1).

Rice. 1. fascial receptacles of the shoulder (scheme according to A.V. Vishnevsky): 1 - sheath of the coracobrachialis muscle; 2 - radial nerve; 3 - musculocutaneous nerve; 4 - median nerve; 5 - ulnar nerve; 6 - vagina of the triceps muscle of the shoulder; 7 - sheath of the shoulder muscle; 8 - sheath of the biceps muscle of the shoulder.

Rice. 2. Right humerus front (left) and back (right): 1 - caput humeri; 2 - collum anatomicum; 3 - tuberculum minus; 4 - coilum chirurgicum; 5 - crista tuberculi minoris; 6 - crista tuberculi majoris; 7 - foramen nutricium; 8 - facies ant.; 9 - margo med.; 10 - fossa coronoidea; 11 - epicondylus med.; 12 - trochlea humeri; 13 - capitulum humeri; 14 - epicondylus lat.; 15 - fossa radialis; 16 - sulcus n. radialis; 17 - margo lat.; 18 - tuberositas deltoidea; 19 - tuberculum majus; 20 - sulcus n. ulnaris; 21 - fossa olecrani; 22 - facies post.

On the anterior-internal surface of the shoulder above its own fascia, two main venous superficial trunks of the limb pass - the radial and ulnar saphenous veins. Radiation saphenous vein(v. cephalica) goes outward from the biceps muscle along the outer groove, at the top it flows into the axillary vein. The ulnar saphenous vein (v. basilica) goes along the internal groove only in the lower half of the shoulder, - the internal cutaneous nerve of the shoulder (n. cutaneus brachii medialis) (printing table, Fig. 1-4).

The muscles of the anterior shoulder region belong to the group of flexors: the coracobrachial muscle and biceps having two heads - short and long; fibrous stretching of the biceps muscle (aponeurosis m. bicipitis brachii) is woven into the fascia of the forearm. Beneath the biceps muscle lies the brachialis muscle. All these three muscles are innervated by the musculocutaneous nerve (n. musculocutaneus). On the outer and antero-medial surfaces of the lower half of the humerus, the brachioradialis muscle begins.

Rice. 1 - 4. Vessels and nerves of the right shoulder.
Rice. 1 and 2. Superficial (Fig. 1) and deep (Fig. 2) vessels and nerves of the anterior surface of the shoulder.
Rice. 3 and 4. Superficial (Fig. 3) and deep (Fig. 4) vessels and nerves of the posterior surface of the shoulder. 1 - skin with subcutaneous fatty tissue; 2 - fascia brachii; 3 - n. cutaneus brachii med.; 4 - n. cutaneus antebrachii med.; 5-v. basilica; 6-v. medlana cublti; 7-n. cutaneus antebrachii lat.; 8-v. cephalica; 9 - m. pectoralis major; 10-n. radialis; 11 - m. coracobrachialis; 12-a. et v. brachlales; 13 - n. medianus; 14 - n. musculocutaneus; 15 - n. ulnaris; 16 - aponeurosis m. bicipitis brachii; 17 - m. brachialis; 18 - m. biceps brachii; 19-a. et v. profunda brachii; 20-m. deltoldeus; 21-n. cutaneus brachii post.; 22-n. cutaneus antebrachii post.; 23-n. cutaneus brachii lat.; 24 - caput lat. m. trlcipitis brachii (cut); 25 - caput longum m. tricipitls brachii.

The main arterial trunk of the shoulder - the brachial artery (a. brachialis) - is a continuation of the axillary artery (a. axillaris) and goes along the medial side of the shoulder along the edge of the biceps muscle along the projection line from the top of the axillary fossa to the middle of the cubital fossa. The two veins accompanying it (vv. brachiales) run along the sides of the artery, anastomosing with each other (tsvetn. fig. 1). In the upper third of the shoulder outside the artery lies the median nerve (n. medianus), which crosses the artery in the middle of the shoulder and then goes from its inner side. The deep artery of the shoulder (a. profunda brachii) departs from the upper part of the brachial artery. Directly from the brachial artery or from one of its muscular branches, the nutrient artery of the humerus (a. nutrica humeri) departs, which penetrates the bone through the nutrient hole.

Rice. 1. Cross cuts of the shoulder, made at different levels.

On the posterior outer surface of the shoulder in the posterior bone-fibrous bed is the triceps muscle, which extends the forearm and consists of three heads - long, medial and outer (caput longum, mediale et laterale). The triceps muscle is innervated by the radial nerve. The main artery of the posterior section is the deep artery of the shoulder, going back and down between the external and internal heads of the triceps muscle and enveloping the humerus with the radial nerve behind. In the posterior bed are two main nerve trunks: radial (n. radialis) and ulnar (n. ulnaris). The latter is located at the top posteriorly and inside of the brachial artery and the median nerve, and only in the middle third of the shoulder enters the posterior bed. Like the median, the ulnar nerve does not give branches on the shoulder (see Brachial plexus).

The humerus (humerus, os brachii) is a long tubular bone (Fig. 2). On its outer surface is the deltoid tuberosity (tuberositas deltoidea), where the deltoid muscle is attached, on the posterior surface is the groove of the radial nerve (sulcus nervi radialis). The upper end of the humerus is thickened. Distinguish between the head of the humerus (caput humeri) and the anatomical neck (collum anatomicum). A slight narrowing between the body and the upper end is called the surgical neck (collum chirurgicum). At the upper end of the bone there are two tubercles: a large one on the outside and a small one in front (tuberculum inajus et minus). The lower end of the humerus is flattened in the anterior-posterior direction. Outward and inward, it has protrusions that are easily palpable under the skin - epicondyles (epicondylus medialis et lateralis) - the place where most of the muscles of the forearm begin. Between the epicondyles is the articular surface. Its medial segment (trochlea humeri) has the shape of a block and articulates with the ulna; lateral - head (capitulum humeri) - spherical and serves for articulation with the beam. Above the block in front is the coronary fossa (fossa coronoidea), behind - the ulna (fossa olecrani). All these formations of the medial segment of the distal end of the bone are united under the general name "condyle of the humerus" (condylus humeri).

- this is a violation of the integrity of the humerus in its upper part, just below the shoulder joint. More often occurs in women of elderly and senile age, the cause is a fall on a hand laid back or pressed to the body. It is manifested by pain, swelling and limitation of movement in the shoulder joint. Sometimes bone crunch is determined. To clarify the diagnosis, an X-ray examination is performed. Treatment is usually conservative: anesthesia, reduction and immobilization. If it is impossible to match the fragments, the operation is performed.

ICD-10

S42.2 Fracture of the upper end of the humerus

General information

Fracture of the neck of the shoulder - damage to the upper end of the humerus. It is more often detected in older women, which is due not only to osteoporosis, but also to a characteristic restructuring of the metaphysis of the humerus: a decrease in the number of bone beams, an increase in the size of the medullary cavities, and thinning of the outer wall of the bone in the area of ​​​​the transition of the metaphysis to the diaphysis. A fracture usually occurs as a result of indirect trauma. It may be impacted, accompanied or not accompanied by displacement of fragments.

In most cases, a fracture of the neck of the shoulder is a closed isolated injury; open injuries in this area are almost never found. With high-energy impacts, combinations with fractures of other bones of the limbs, pelvic fracture, spinal fracture, head injury, rib fractures, blunt abdominal trauma, rupture Bladder, kidney damage, etc. Treatment of fractures of the neck of the shoulder is carried out by orthopedic traumatologists.

Causes

According to the observations of specialists in the field of traumatology and orthopedics, usually the cause of a fracture of the neck of the shoulder is an indirect injury (falling on the elbow, shoulder or hand), in which there is a flexion of the bone in combination with pressure on it along the axis. The effect of applied forces depends on the position of the hand at the time of injury. If the limb is in a neutral position, the fracture line is usually transverse. The peripheral fragment is introduced into the head, an impacted fracture is formed. In this case, the longitudinal axis may be preserved, but the formation of a more or less pronounced angle, open posteriorly, is more often observed.

If the shoulder is in the adduction position at the time of injury, the central fragment “goes” into the abduction position and turns outward. In this case, the peripheral fragment turns inward, shifts anteriorly and outwards. An adduction fracture occurs, in which the angle between the fragments is open posteriorly and medially. If the inner edge of the distal fragment is embedded in the head, an impacted adduction fracture of the surgical neck of the shoulder is formed. If the introduction does not occur (it is quite rare), damage is formed with a complete displacement and separation of the fragments.

When the shoulder is abducted at the time of injury, the central fragment “leaves” into the adduction position and turns inwards. In this case, the peripheral fragment is pulled forward and upward, turns inward and moves anteriorly. The fragments form an angle open posteriorly and outwards. This injury is called an abduction fracture. As in the previous case, with abduction injuries, a part of the peripheral fragment usually penetrates into the head of the shoulder; complete separation and displacement of the fragments is rarely detected. The most common fractures are abduction.

Pathoanatomy

The humerus is a long tubular bone consisting of a diaphysis (middle), two epiphyses (upper and lower) and transitional zones between the diaphysis and epiphyses (metaphyses). The upper end of the bone is represented by a spherical articular head, immediately below which is a natural narrowing - the anatomical neck of the shoulder. Fractures in this area are very rare. Just below the anatomical neck are two tubercles (places of attachment of muscle tendons) - large and small.

Below the tubercles and above the place of attachment of the pectoralis major muscle, there is a conditional border between the upper end and the diaphysis of the bone. This border is called the surgical neck of the shoulder, it is in this area that fractures most often occur. The articular capsule of the shoulder joint is attached just above the tubercles, so transtubercular fractures, as well as fractures of the actual surgical neck of the shoulder, are classified as extra-articular injuries. The division of these injuries is very conditional, taking into account the general symptoms and principles of treatment, most clinicians combine them into a general group of fractures of the surgical neck of the shoulder.

Such fractures usually heal well, the formation of false joints is extremely rare. However, in the presence of a sufficiently pronounced displacement and the absence of reposition in the long-term period, a significant limitation of movements is possible, due to both the consolidation of fragments in the wrong position and the proximity of the ligaments and the articular bag, which are easily involved in the adhesive process. The most unfavorable from the point of view of the subsequent limitation of function is an unrepaired adduction fracture, after which a pronounced restriction of abduction may occur.

Fracture symptoms

Patients with impacted fractures of the neck of the shoulder complain of moderate pain in the joint area, aggravated by movement. The joint is edematous, hemorrhages are often found. Active movements are possible, but limited due to pain. Palpation of the head of the shoulder is painful. With fractures with displacement, the symptoms are more pronounced: the rounded shape of the joint is disturbed, some protrusion of the acromial process and retraction in the head region are noticeable.

A change in the axis of the shoulder is noted: it runs obliquely, while the central end of the axis is directed forward and inward. The elbow is displaced backward and away from the body, however, there is no fixation of the elbow joint (as in case of dislocation), the symptom of spring resistance is not detected. The shortening of the diseased shoulder by 1-2 cm is determined. Active movements are impossible, passive ones are sharply limited due to pain and are sometimes accompanied by a bone crunch. During rotational movements, the head does not move with the humerus.

On palpation of the surgical neck, there is a sharp local pain. In thin patients with poorly developed muscles in the armpit, it is possible to palpate the end of the distal bone fragment. In some cases, a displaced fragment can compress the neurovascular bundle, which is manifested by cyanosis due to impaired venous outflow, swelling of the limb and a feeling of crawling.

Diagnostics

To clarify the diagnosis, an x-ray of the shoulder joint is prescribed in two projections: direct and "epaulet" (axial). An "epaulette" shot is performed by moving the shoulder away from the body at an angle of 30-40 degrees. Greater abduction is categorically not recommended, as it can aggravate the displacement of fragments. In doubtful cases, CT of the shoulder joint is used. If compression of the neurovascular bundle is suspected, patients are referred for a consultation with neurologists or neurosurgeons and vascular surgeons.

Treatment of a fracture of the neck of the shoulder

Elderly patients with impacted fractures do not require reposition in most cases. The area of ​​damage is anesthetized with novocaine and a fixing bandage is applied for a period of 6 weeks. If a moderately displaced impacted fracture has been diagnosed in a young or middle-aged person, reduction is indicated. For patients of all ages, reposition is performed for comminuted and non-impacted fractures. Then the limb is immobilized, painkillers and UHF are prescribed. Therapeutic exercises begin from the second day, light movements (slight adduction, abduction and swaying) in the shoulder joint - from the fifth day. Subsequently, the range of motion is gradually increased.

As a means for immobilizing a fracture, depending on the nature of the damage and the age of the patient, a conventional scarf bandage (in senile patients) or a snake scarf, on which a bent arm is hung, can be used. If necessary, the scarf is supplemented with a roller in the armpit. In some cases, with impacted adduction fractures with angular displacement and easily displaced non-impacted fractures with complete divergence of fragments, skeletal traction is performed on the abduction or abduction splint.

Surgical treatment is indicated for significant angular displacement, complete separation of the fragments and the impossibility of matching the fragments by closed reposition. The operation is carried out in a traumatology department under general anesthesia. As a rule, an antero-medial incision is used. To hold fragments in adults, osteosynthesis with a plate is performed; in children, fixation with knitting needles is possible. The wound is sutured in layers and drained.

IN postoperative period immobilization is carried out using a curved Kremer splint or bandage with a pad in the armpit. Painkillers and antibiotics are prescribed. From the third day, exercise therapy begins with movements in the fingers, elbow and wrist joint. The sutures are removed on the 10th day, movements in the shoulder joint begin on the 20th day after the operation. results surgical intervention usually good.

Very rarely, with crushing of the upper parts of the humerus and aseptic necrosis of the head, arthroplasty of the shoulder joint is indicated. Depending on the age and physical condition of the patient, it is possible to use unipolar endoprostheses (replacement of only the head of the humerus) or total endoprosthesis (replacement of both the head and glenoid cavity of the scapula). If there are contraindications to endoprosthetics, arthrodesis is performed.