The brachial plexus and its nerves. Brachial and lumbosacral nerve plexus lesions

Damage to it occurs in a narrow costoclavicular space formed in front by the clavicle and subclavian muscle, behind and inside 1 rib with scalene muscles attached to it, behind and on the side - by the upper edge of the scapula (costoclavicular Falconer-Weddell syndrome)) or lower - at the point of transition of the neurovascular bundle to the axillary region - due to its bending through the tendon of the pectoralis minor muscle when the arm is abducted ( Wright's hyperabduction syndrome).

An essential sign of this localization of the lesion is the involvement in the process of compression of the subclavian or axillary vein, which is manifested by swelling, cyanosis of the hand of a transient or permanent nature, up to vein thrombosis, usually provoked by overexertion, - Paget-Schretter syndrome (see above). Neurological deficit is represented by paresis of the hand due to impaired conduction along the ulnar nerve and partial damage to the median nerve, as well as paresthesia and hypoesthesia in the zone of innervation of the internal cutaneous nerves of the shoulder and forearm. These symptoms are clinically difficult to distinguish from those in lesions of the lower primary bundles of the brachial plexus. Therefore, in their diagnosis, it is necessary first of all to take into account the posture that provokes pain, predisposing factors and the characteristic localization of pain points.

costoclavicular syndrome

Compression of the neurovascular bundle occurs in a vertical position when the shoulder girdle is retracted back and down. This situation occurs when carrying heavy loads in a backpack, knapsack. Predisposing factors are neurodystrophic changes in the subclavian muscle and costo-coracoid ligament, anomalies and post-traumatic deformities of the clavicle and rib, curvature of the cervicothoracic junction of the spine. Trigger points are found in the subclavian muscle. The costoclavicular maneuver consists in the fact that the patient assumes a military pose - at attention and takes a maximum breath; at this time, the pulse disappears and paresthesia and pain appear along the ulnar edge of the hand and forearm on the side of the lesion. With a long course of the disease, there is a constant swelling of the hand due to chronic venous insufficiency.

Hyperabduction syndrome

Neurovascular disorders progress as a result of repeated traumatization of the brachial plexus and axillary vessels when working with raised arms (electricians, fitters) or in people who have the habit of sleeping with their hands behind their heads. In this position, the neurovascular bundle is bent and compressed by the tendon of the pectoralis minor muscle, the coracoid process and above - between the clavicle and the first rib. Placing a hand behind the head leads to the disappearance of the pulse and an increase in the symptoms of the disease. On palpation, pain in the pectoralis minor muscle, the coracoid process of the scapula is determined. Mobility in the shoulder joint is limited due to pain. There is varicose veins on the anterior wall of the chest. Often, the immediate provoking moment of the disease is an injury to the anterior wall of the chest.

Neuropathy of the long nerve of the chest

The nerve is formed by short posterior bundles C5 - C7) is located on the anterior surface of the middle scalene muscle, where it can undergo compression and an isolated lesion, which is manifested by atrophy of the serratus anterior muscle, distance of the lower angle of the scapula from the chest, difficulty in raising the arm above the horizontal (when shaving, combing hair). The pain is localized in the depths of the lateral surface of the neck, here, behind the lower half of the sternomastoid muscle, painful points are palpated.

Neuropathy of the suprascapular nerve

Formed from the branches of the upper trunk of the brachial plexus, the nerve passes under the trapezius muscle to the subclavian region, then goes posteriorly, bending over the edge of the scapula in the suprascapular notch; here it is covered by the superior transverse ligament of the scapula. Upon reaching the posterior surface of the scapula, the nerve gives off sensory branches to the acromioclavicular joint and shoulder joint and is distributed in the supraspinatus muscle, the distal branch penetrates through the spinoglenoid notch into the infraspinatus fossa, where it innervates the muscle of the same name. At the level of the spine, the nerve is covered by the inferior transverse ligament of the scapula.

The most common site for compression of the suprascapular nerve is the notch of the scapula, which is stenotic due to hypertrophy of the superior transverse ligament. Pathology is manifested by pain in the acromioclavicular joint, shoulder joint, along the lateral edge of the scapula with impaired abduction and external rotation of the arm, atrophy of the supra- and infraspinatus muscles of the scapula. Damage to the nerve at the level of the spine as a result of compression of the altered inferior transverse ligament of the scapula leads to isolated hypotrophy of the infraspinatus muscle. Tunnel lesions of the suprascapular nerve occur with neurodystrophic changes in the muscles of the shoulder girdle (trapezius, pectoral, supraspinatus), in the ligaments of the scapula, shoulder joint. Direct symptoms of the disease are often detected after a slight injury or overload of the shoulder girdle (weight lifting, throwing movements).

Axillary neuropathy

The nerve departs in the axillary region from the posterior secondary bundle of the brachial plexus and goes posteriorly into a quadrilateral opening formed by the small and large round muscles above and below and the humerus and the long head of the triceps muscle - respectively, from the outside and from the inside. Having rounded the posterior surface of the surgical neck of the humerus, the nerve is distributed in the deltoid and teres minor muscles, and the cutaneous branch, spreading over the posterior edge of the deltoid muscle, innervates the posterior surface of the shoulder. One of the terminal branches of the axillary nerve is the intertubercular nerve, which is located between the tubercles of the head of the humerus and is directly involved in the innervation of the tendon-ligamentous apparatus and the capsule of the shoulder joint.

Tunnel damage to the nerve is possible in the quadrilateral foramen, in the region of the posterior edge of the deltoid muscle and the intertubercular zone of the humerus. In the first case, the lesion of the main trunk is manifested by atrophy of the deltoid muscle with impaired abduction of the arm to the side, hypesthesia or hyperesthesia in the posterior outer region of the shoulder.

Compression of sensitive branches is accompanied by pain in the shoulder joint, shoulder, in the armpit. Soreness is determined on palpation along the posterior edge of the deltoid muscle and the intertubercular point. Compression-ischemic neuropathy of the axillary nerve and its branches develops as a result of neurodystrophic changes in the shoulder joint and muscles of the shoulder girdle (deltoid, round, triceps) in combination with overload of the shoulder girdle.

Neuropathy of the musculocutaneous nerve

As a continuation of the lateral trunk of the brachial plexus, the nerve on the shoulder innervates the biceps, coracobrachial and brachial muscles, then, passing through the brachial fascia at the level of the elbow crease outside of the biceps tendon, it is divided into the anterior and posterior external nerves of the forearm (Fig. 29).

The sensitive part of the nerve at the level of the elbow crease is subjected to compression. Patients are concerned about pain in the elbow and on the lateral surface of the forearm, burning paresthesias are also localized here. There is pain on palpation at the site of nerve compression. Symptoms are aggravated by pronation-supination of the forearm and by flexion-extension in the elbow joint. The zone of hyperesthesia, hypoesthesia with elements of hyperpathy is determined by the outer surface of the forearm. In patients with tunnel neuropathy of the external cutaneous nerve of the forearm, moderately pronounced neurodystrophic changes in the elbow joint, manifestations of external epicondylitis are often observed.

median nerve neuropathy

The nerve is formed from the external and internal bundles of the brachial plexus in front of the subclavian artery, contains fibers of the spinal nerves C5 - T1, heading down the medial groove of the shoulder, crosses the elbow bend in front, where it gives branches to the pronator teres, superficial flexor of the fingers, radial flexor of the wrist, long palmar muscle and deep flexor of the fingers (mainly the first and third). On the anterior surface of the forearm, the nerve pierces the fibrous fascia of the biceps tendon, then lies between the two heads of the round pronator, giving off the anterior interosseous nerve, supplying the long flexor of the thumb, the deep flexor of the fingers (mainly the second) and the square pronator. Further, the nerve is located under the tendinous arch of the superficial flexor of the fingers, when approaching the wrist it gives off a palmar cutaneous branch and enters the carpal tunnel, covered with a holder of the wrist flexors. In the depths of the palm, it innervates the muscles of the elevation of the thumb (except for the adductor), the first two worm-like muscles and provides sensitivity in the palm and palmar surface of the first - third and 1/2 of the fourth fingers (Fig. 29).

High compression of the median nerve in the armpit is known as honeymoon paralysis. In these cases, while sleeping on the same bed, the wife's head compresses the nerve in the armpit. Initially, paresthesias occur on the palmar surface of the hand, and after repeated cases, paresis of the flexors of the hand and pronators, weakness of flexion of the proximal phalanges of the fingers and distal phalanges of the thumb and forefinger, hypotrophy of the muscles of the elevation of the thumb, hypoesthesia on the hand develop.

Supracondylar ulnar canal syndrome develops in people who have a bone protrusion on the medial surface in the lower third of the humerus, to which the ligament from the medial epicondyle of the shoulder is attached, forming a canal in which the median nerve and brachial vessels are enclosed. This situation occurs in 1-3% of people. bone spike
determined on a tangential radiograph. In the presence of dystrophic changes in the ligament, stenosis of the canal occurs with compression of the neurovascular bundle, which is accompanied by pain, paresthesia, especially during pronation and extension of the forearm; motor defect is expressed insignificantly. Pressure on a point immediately behind the supracondylar apophysis provokes local pain and paresthesia in the hand. round pronator syndrome associated with compression of the median nerve in the upper forearm under the fibrous ligament of the biceps tendon, between the heads of the pronator teres or under the tendon of the superficial flexor of the fingers. The compression of the nerve increases with forced flexion of the fingers, pronation and flexion of the forearm, while pain in the upper part of the forearm increases, the hand and the first two fingers go numb. There is a sharp pain in the projection of the round pronator; the muscle is compacted, its percussion causes paresthesia. Paresis is more pronounced in the flexors of the thumb and in the muscles of the elevation of the thumb.

Anterior interosseous nerve syndrome due to its compression by the fibrous tissues of the forearm as a result of acute or chronic overload of the muscles of the forearm (carrying a load on half-bent forearms, performing pulling or rotational movements with the hand). Pathology is manifested by dull pain in the middle third of the forearm, awkwardness of the hand due to weakness of the long flexors of the thumb and forefinger, which take the characteristic pinch position. Sensitivity on the hand and fingers is preserved.

carpal tunnel syndrome is the most common human tunnel neuropathy, more commonly seen in middle-aged women engaged in intensive manual work. Nerve compression is promoted by congenital narrowness of the canal and neurodystrophic changes in the transverse ligament of the wrist. The median nerve enters the carpal tunnel under the fibrous cord of the flexor retinaculum 1 cm above the distal carpal fold. The palmar sensory branch departs 3 cm proximal to the canal, so sensory disturbances in the form of hypesthesia or hyperesthesia are limited to the first - fourth fingers of the hand and are not detected in the palm of your hand. Paresthesia in the fingers, pain in the hand with irradiation in the forearm, hyperhidrosis, swelling of the hand form the basis of the syndrome. Symptoms of the disease are sharply increased at night, especially when lying on the affected side. Relief brings shaking, rubbing the brush. In severe cases, patients cannot sleep due to severe pain in the arm. Hypotrophy of thenar, weakness of abduction and opposition of the thumb are found only in advanced cases, several months or years after the onset of the disease.

For the clinical diagnosis of the syndrome, the positive symptoms of Tinel (slight tapping of the median nerve at its entrance to the carpal tunnel) and Phalen (flexion or extension of the wrist at a right angle for 1 min), elevation and tourniquet tests, which reproduce pain and dysesthesia in zone of innervation of the median nerve.

Intermetacarpal Tunnel Syndrome occurs when the common palmar digital nerve is damaged between the heads of the metacarpal bones. The pain is localized between adjacent fingers, spreading to the back of the hand and forearm. Palpation tenderness is determined in the projection of the heads of the metacarpal bones, while numbness and paresthesia appear along the adjacent surfaces of the fingers, and a zone of hypesthesia can also be identified here. Maximum flexion or extension of the fingers exacerbates the symptoms of the disease.

Radial nerve neuropathy

The nerve is formed from the posterior trunk of the brachial plexus, descending along the posterior wall of the armpit, reaches the zone of the brachio-muscular angle, where it is adjacent to the dense lower edge of the latissimus dorsi muscle and the tendon of the long head of the triceps muscle. Further, the nerve goes around the humerus, located in a spiral groove. Here branches depart to the triceps muscle of the shoulder and the ulnar muscle. Immediately upon exiting the forearm between the biceps and the brachioradialis muscles, the nerve is located on the brachialis muscle and gives motor branches to the brachioradialis muscle and the long and short radial extensors of the hand. A little lower in the proximal part of the forearm, the nerve divides into a superficial sensory branch, which descends under the cover of the brachioradialis muscle to the dorsal surface of the lower third of the forearm and divides under the skin into five dorsal digital nerves for the first two and the radial half of the third finger, and a deep one that passes between the bundles supinator or in 30% of cases through the fibrous edge of the arch support (Froze's arcade). Before the entrance and in the channel of the arch support there are muscle branches to the extensors of the wrist and the arch support; upon exiting the canal, the extensor of the fingers and the ulnar extensor of the hand are innervated. The final branch is the posterior interosseous nerve of the forearm, which is located between the long and short extensors of the thumb and innervates them, as well as the long muscle that abducts the thumb, extensors of the index finger and little finger (Fig. 29).

High compression of the radial nerve at the level of the shoulder-axillary angle (with a crutch, chair back, edge of the operating table, bed), in addition to paresis of the extensors of the hand and fingers, leads to weakness of the triceps and hypoesthesia along the back of the shoulder and forearm, a decrease in the triceps reflex.

Nerve injury in the spiral canal between the heads of the triceps muscle (blunt trauma, fracture of the humerus, compression of the callus) is accompanied by paresis of the extensor muscles of the hand, while maintaining the function of the triceps muscle and sensitivity on the shoulder. Percussion of the compression site in the projection of the groove of the radial nerve causes local pain and paresthesia in the area of ​​the anatomical snuffbox.

The most common localization of compression-ischemic injury is the level external intermuscular septum of the shoulder, where the radial nerve is compressed during deep sleep with a hand hanging over the edge of a bed, bench, or operating table (<<сонный», «субботний», «алкогольный», «наркозный» паралич). «Свисающая кисть>, hypotrophy of the dorsal muscles of the forearm, especially the brachioradialis muscle, form the basis of the clinical picture. A small zone of hypesthesia is limited to the area of ​​the dorsum of the hand between the first and second fingers.

The radial nerve may be subjected to compression over the l lateral epicondyle of the shoulder, fibrous arch of the lateral head of the triceps, in the area of ​​the elbow joint and upper third of the forearm(fractures, degenerative joint lesions, bursitis, benign tumors). The neurological syndrome is the same as in sleep paralysis. The slow rate of development of the disease, palpation, X-ray allow you to make the correct diagnosis.

supinator syndrome - the result of compression of the deep branch of the radial nerve in the region of the supinator or Froze's arcade is manifested by pain in the depths of the outer sections of the ulnar region and on the back of the hand, forearm. Pain is provoked by heavy manual work, intensified after sleeping on a sore arm. Weakness of supination and extension of the main phalanges of the fingers is noted, which causes awkwardness of the hand during work. The maximum supination of the arm, bent at an angle of 450 in the elbow joint, causes increased pain. Palpation reveals induration and tenderness of the supinator in the median groove of the forearm.

Posterior interosseous nerve syndrome associated with its compression below the supinator level. In this case, the pain is mild or completely absent. Characterized by slowly progressive weakness in the extensors of the fingers, mainly the thumb and forefinger, and radial deviation of the hand during extension.

Damage to the superficial sensory branch of the radial nerve more often occurs in the lower third of the forearm, on the back of the wrist; it may be associated with de Quervain's disease (ligamentosis of the 1st canal of the dorsal carpal ligament) or due to traumatization of the superficial branches by a watch bracelet, handcuffs, athletes' wristbands. Numbness and burning pain are felt on the back surface of the radial edge of the hand and the first or second fingers. The pain may radiate up the arm to the shoulder. The symptom of percussion of the affected branch is sharply positive. A local thickening of the subcutaneous branch can be detected in the form of a pseudoneuroma.

Ulnar nerve neuropathy

The nerve is the longest branch of the medial bundle of the brachial plexus. At the level of the middle third of the shoulder, the nerve departs from the brachial artery and penetrates through the internal intermuscular septum of the shoulder, heading between the medial epicondyle of the shoulder and the olecranon under the supracondylar ligament on the forearm. Here it gives off a small articular branch and innervates the ulnar flexor of the wrist. Next, the nerve leaves the cubital canal and goes between the ulnar flexor of the wrist and the deep flexor of the fingers to the Guillain canal, covered with a fibrous ligament stretched between the pisiform and hamate bones. At a distance of 6 - 8 cm from the wrist, the dorsal cutaneous branch departs from the nerve, innervating the corresponding surface of the fifth, fourth and half of the third fingers, as well as the inner edge of the hand. The main trunk of the nerve, leaving the Guillain canal, is divided into superficial and deep branches. Superficial supplies the short palmar muscle and conducts sensitivity from the medial surface of the palm, little finger and half of the ring finger. The deep branch provides innervation to most of the small muscles of the hand and the lesser eminence (Fig. 29).

Cubital Canal Syndrome. The nerve is most susceptible to injury in the elbow region. Here it is located in the canal on a dense bone bed, is easily injured by a direct blow and is compressed chronically when working at a table or desk. According to the same mechanism, the nerve is compressed in bedridden patients (compression on the edge of the bed, when resting on the elbows, on a hard mattress in the supine position), after prolonged anesthesia, alcohol intoxication, coma, with prolonged sitting in a chair with uncomfortable armrests, in drivers who have a habit of hanging their arm through the window. In people with valgus deformity of the elbow (a congenital variant of the structure or a consequence of an injury), the nerve is injured on the wing of the ilium when carrying heavy loads.

The second mechanism of microtraumatization of the ulnar nerve is its recurrent subluxation in the cubital canal with anterior displacement to the anteromedial surface of the internal epicondyle of the shoulder at the moment of arm flexion in the elbow joint, which is facilitated by congenital or acquired weakness of the ligament covering the ulnar groove, underdevelopment or posterior location of the epicondyle.

The third mechanism is stenosis of the cubital canal, which can occur due to developmental anomalies (hypoplasia of the epicondyle, the presence of the supracondylo-ulnar muscle, abnormal attachment with protrusion of the medial head of the triceps muscle), be congenital (constitutional narrowness of the canal), degenerative (with dystrophic changes in the elbow joint, in the medial collateral ligament lining the canal floor, and in the fibro-aponeurotic triangular ligament of the canal roof, which extends between the medial epicondyle and the olecranon) and post-traumatic. Other variants of stenosis are associated with tumors (chondromatosis of the elbow joint, ganglion of the ulnar sulcus), inflammatory processes in the joint (rheumatoid and psoriatic arthritis), or neurogenic osteoarthropathy.

The clinical picture of the cubital canal syndrome is primarily represented by paresthesias, numbness along the medial surface of the forearm and hand. Deep aching pains can also be felt here. Finger compression of the nerve or its percussion increases pain, dysesthesia. Over time, hypoesthesia develops in the zone of innervation. Even intense compression of the nerve trunk at the level of the cubital canal does not cause pain. Atrophies of the first dorsal interosseous muscle, hypothenar, small muscles of the hand become apparent, which is accompanied by an increase in paresis of the hand. Weakness of the palmar interosseous muscles leads to a violation of the convergence of the fingers, which is often manifested by the posture of the allotted little finger (Wartenberg's symptom). Paresis of the adductor muscle and the short flexor of the thumb is detected when trying to bring the thumb and small fingers together, which can only be done by bending the thumb in the interphalangeal joint (Froment's symptom). With severe paresis, the hand takes the form of a “clawed paw”, which is caused by weakness of the worm-like muscles in combination with an excess of extensors. Noteworthy is a relatively small dysfunction of the hand in the presence of gross atrophy.

Guillain's ulnar carpal tunnel syndrome. Compression of the nerve at the entrance and in the proximal part of the canal is manifested by paresis of all the muscles of the hand innervated by the ulnar nerve, sensory disturbances in the hypothenar region, the palmar surface of the fifth and medial half of the fourth fingers. Sensitivity is preserved on the back of the medial surface of the hand, corresponding to two and a half fingers, and the function of the ulnar flexor of the wrist, branches to which extend to the forearm. Compression of the nerve between the pisiform bone and the hook of the hamate in the distal parts of the canal is represented by a motor deficit without sensory impairment. Finally, there may be an isolated lesion of the superficial branch of the nerve with a clear tender palmar ulnar defect. Tinel's sign and ischemic test are positive.

In addition to neurodystrophic changes in the ligaments, bones of the wrist, the consequences of fractures and benign tumors, a ganglion originating from fibrous connections between the bones at the bottom of the Guillain canal can be a frequent specific cause of compression of the ulnar nerve at this level. The provoking and pathogenetic moments of this lesion are labor and sports injuries of the base of the palm, especially among mechanics, plumbers, polishers, cyclists, gymnasts, as well as the habit of closing the desk drawer with a palm strike.

Syndrome of compression-ischemic neuropathy of the dorsal branch of the ulnar nerve occurs as a result of chronic microtraumatization of it on the medial surface of the wrist 1 cm above the head of the ulna (the habit of leaning on the edge of the table when typing on a typewriter, while listening to a lecture), and can also be a complication of ulnar styloidosis. Diagnosis of this syndrome is based on the typical localization of sensory disorders, on the back half of the medial surface of the hand and the main phalanges of the third - fifth fingers. Characterized by pain on the medial surface of the hand, in the fifth metacarpal bone. A painful point, the irritation of which causes typical pain and paresthesia, is found in the styloid process of the ulna (Fig. 30).

Neuropathy of the lumbar plexus

The plexus is located high in the abdominal cavity under the diaphragm on the anterior surface of the square muscle, is formed from the anterior branches of the spinal nerves TI2 - L4, covered by the psoas major muscle, the iliac, ilioinguinal, femoral-genital, lateral cutaneous thigh, obturator and femoral nerves sequentially depart from the plexus . Compression-ischemic lesion of the lumbar plexus is due to neurodystrophic changes in the upper lumbar vertebrae, in the square and large lumbar muscles; retroperitoneal hematomas (spontaneous, against the background of anticoagulant therapy, traumatic genesis); inflammatory processes (retroperitoneal abscess, phlegmon, myositis); benign, malignant and metastatic tumors. The usual causes of plexus damage are penetrating wounds of the lumbar region, bone fragments, hematomas in massive fractures of the spine and pelvic bones.

The clinical picture of compression-ischemic plexopathy of this localization is manifested by pain and paresthesia in the lower abdomen, in the pelvic girdle, in the thigh, which increase when the outstretched leg is raised, with deep palpation between the lower rib and the iliac crest. Later, hypotrophy of the muscles of the pelvic girdle and thigh appears with impaired extension and adduction of the leg, with difficulty in gait. Typically, a partial lesion with predominant involvement of one or three nerves in the process (usually unilateral).

It develops as a result of nerve compression at the lateral edge of the iliac muscle and on the anterior surface of the square psoas muscle by a lowered kidney; at the iliac crest in the transverse and internal oblique muscles of the abdomen; under the aponeurosis of the external oblique muscle of the abdomen above the pupart ligament; at the anterior wall of the vagina of the rectus abdominis muscle above the outer ring of the inguinal canal. Iatrogenic injuries are not uncommon after operations in the small pelvis and herniotomy. Pain and paresthesia are localized along the outer surface of the femoral-gluteal region, above the gluteus medius muscle, tensor fascia of the thigh, above the greater trochanter, in the lower abdomen above the inguinal fold. Increased pain is caused by walking, tilting the body forward, palpation at the point of compression of the nerve in the muscle and aponeurosis. The zone of hypesthesia is determined above the inguinal ligament; with a high lesion, it also includes the skin over the gluteus medius muscle. Weakness of the muscles of the abdominal wall in the lower abdomen on the side of the lesion may be detected.

Neuropathy of the ilioinguinal nerve

It may be due to compression of the nerve intratabdominally, medially from the anterior superior iliac spine, where it penetrates at a right angle into the oblique muscles of the abdomen, and in the inguinal canal. Patients complain of pain, paresthesia in the inguinal region, above the womb, in the upper part of the external genital organs. Painful points are determined 1 cm medially from the superior anterior iliac spine or in the region of the external opening of the inguinal canal. In some cases, there is a characteristic antalgic posture with flexion and internal rotation of the hip, forward tilt of the body when walking. An objective examination reveals a zone of hypesthesia along the inguinal ligament, above the womb and above the upper sections of the external genital organs, as well as in a small area of ​​the upper inner thigh.

Limitation of mobility of the spine, tenderness of the interspinous and paravertebral points at the level of TXII - LIII or signs of instability of the upper lumbar spine are determined in patients with vertebrogenic neuropathy of the ilioinguinal nerve. The development of degenerative changes in the spine is facilitated by the consequences of traumatic or inflammatory processes in the lower thoracic and upper lumbar spine (compression fractures, synostosis after tuberculous spondylitis). Hormonal spondylopathy or cancer metastases to the spine may be the cause of neuropathy in the elderly. At a young age, idiopathic kyphoscoliosis, thoracolumbar form of Scheuermann-Mau disease, pathology of the hip joint are more often detected, which are accompanied by pelvic distortion, overstrain of the lower muscles of the abdominal wall, which leads to compression-ischemic damage to the ilioinguinal nerve in the myofascial canal near the superior anterior iliac spine.

Traumatic nerve injuries are noted after appendectomy, hernia repair, urological and gynecological operations. The development of neuropathy is promoted by diseases of the genitourinary system (nephrolithiasis, kidney tumors, chronic adnexitis, prostatitis), retroperitoneal hematomas, phlegmon, pararenal nape and their consequences in the form of a cicatricial adhesive process. In the inguinal region, the nerve can be compressed by a lipoma, hernia, or an enlarged lymph node.

Neuropathy of the genitofemoral nerve

Originating from the superior lumbar spinal nerves, the genitofemoral nerve descends along the anterior surface of the psoas major behind the ureter towards the inguinal canal. The femoral branch passes under the pupart ligament outward and anterior to the artery of the same name, then through the cribriform plate of the wide fascia of the thigh and innervates the skin of the upper part of the femoral triangle. The genital branch crosses the external iliac artery and enters the deep annulus of the inguinal canal. After leaving the canal through the superficial ring, it innervates the skin of the scrotum, the inner surface of the thigh, the testicle, the muscle that lifts the testicle in men, in women - the labia majora, the round ligament of the uterus. In addition to compression factors similar to those in neuropathies of the ilioinguinal and iliohypogastric nerves, selective compression of the femoral branch in the vascular space under the inguinal ligament or the genital branch inside the inguinal canal may occur.

Paresthesia and pain in the groin, in the vulva, in the testis with irradiation to the upper inner thigh, aggravated in a vertical position, with palpation of the lower edge of the pupart ligament outward from the femoral artery or the area of ​​the inguinal ring, a positive Wassermann symptom and hypesthesia in the corresponding zone characteristic of tunnel neuropathy of the femoral-genital nerve.

Enough. This may be the result of a birth injury (compression during childbirth with instruments or stretching of the plexus at birth). The callus formed after a clavicle fracture can compress the plexus. Dislocation of the head of the humerus can also cause damage to the plexus. In addition, trauma with cold weapons, a tourniquet applied for a long time, contracture of the scalene muscles, and other causes.

So, peripheral paralysis and anesthesia of the upper limb are usually observed when the entire brachial plexus is affected (Fig. 15). The etiology of this process is traumatic, quite often there can be a birth injury, dislocation of the head of the shoulder, sprain and even tear of the plexus due to forceful abduction and elevation of the shoulder, awkward movement during gymnastics.

If the upper primary trunk of the plexus of the 5.6 cervical roots is damaged, paralysis, atrophy of the proximal muscles of the limb (biceps, deltoid brachial, brachioradial and supinator) are observed. In this case, the shoulder hangs freely, the forearm is in a state of pronation, and the palm is turned back. Neuropathologists refer to this symptom as "tipping waiter" or Duchenne-Erb palsy (upper palsy).

If adjacent roots are involved in the process, then paralysis of the following muscles is observed: anterior serratus, rhomboid muscle that lifts the scapula, as well as the triceps muscle, radial flexor and extensor of the hand, pronator round, long palmar muscle, as well as flexors and extensors thumb. There is atrophy of the muscles of the scapula, the impossibility of abduction and elevation of the shoulder, flexion of the arm in the elbow joint. The biceps reflex and the radial reflex disappear. There is a disorder of sensitivity, which runs along the entire upper limb along its outer surface.

Above the clavicle, outward from the attachment of the sternocleidomastoid muscle lies Erb's point, which is painful when palpated. Electrical stimulation of this point causes a general contraction of all muscles suffering from Duchenne-Erb palsy.

Damage to the lower primary (C7-Th1) plexus trunk leads to paresis of the muscles of the forearm, paralysis and atrophy of the flexors of the fingers, as well as small muscles of the hand and fingers (Fig. 16). In this case, the movement of the shoulder is preserved (syndrome of "cat's paw"). This is Dejerine-Klumpke palsy (lower palsy). It usually appears after excessive pulling of the baby's arm up during labor, with dystocia of the baby's shoulders, with a narrow pelvis or large fetus, as this leads to a violation of Th1.

Damage to this section of the plexus can also occur with direct impact on it (wound, reduction of dislocation of the shoulder joint, etc.), as a rule, the severity of paralysis depends on the severity of damage to the nerves of the plexus. At the same time, there is a paralysis of the deep muscles of the hand (muscles of the elevation of the thumb and little finger, interosseous and worm-like muscles), numbness in the zone of innervation of the ulnar nerve. Anesthesia covers the inner surface of the shoulder, forearm and hand. When the first thoracic vertebra Th1 is involved in the process, in parallel with this, Bernard-Horner syndrome (ptosis, pupillary constriction and unilateral anhidrosis) may appear.

Dejerine-Klumpke paralysis can develop with a number of pathological processes in the region of the 1st rib: a tumor of the apex of the lung, an additional cervical rib, resulting in pressure on the lower trunk of the brachial plexus.

With damage to the axillary nerve (n. axillaris) the patient cannot raise his arm to a horizontal level. Atrophy of the deltoid muscle gradually develops, sensitivity along the lateral surface of the upper edge of the shoulder is disturbed. In addition, looseness develops in the shoulder joint.

Neuritis of the radial nerve (n. radialis) is more common than others, and its manifestations depend on the level of the lesion. When a nerve is damaged in the axillary region, first of all, paralysis of the muscles that are innervated by the radial nerve occurs.

Damage to the radial nerve in the middle third of the shoulder can occur as a result of a fracture of the humerus in this area and with a fracture of the neck of the radius (Fig. 1.8.6). There is hypoesthesia on the back of the shoulder and weakness of the extension of the forearm, inhibition of the triceps reflex. Extension of the hand and main phalanges of the II-V fingers becomes impossible. In this case, the patient's hand takes on the shape of a hanging hand (seal's paw) (Fig. 18), since the innervation of the extensor muscles of the wrist and fingers is disturbed. Damage to the radial nerve makes it impossible to extend and abduct the thumb (paralysis of the long abductor thumb muscle).

Supination of the extended forearm is impossible (bent is possible due to the biceps muscle). Flexion of the pronated forearm is also impossible due to paralysis of the brachioradialis muscle. Areas of hypoesthesia extend to the outer part of the dorsum of the hand, the main phalanges I, II and the radial surface of the III finger.

With more distal lesions of the radial nerve, the extensors of the hand and fingers are mainly affected.

If the median nerve is damaged, especially in the ulnar region and on the forearm, pronation, palmar flexion of the hand, flexion in the distal interphalangeal joints of the II and III fingers is disturbed due to the pathology of the innervation of the superficial and deep flexors of the fingers from the radial side. Opposition of the first finger and flexion of its terminal phalanx becomes impossible due to damage to the long and short flexors of the thumb. The flexion of the fingers in the proximal interphalangeal joints of the II and III fingers is also disturbed due to paralysis of the I and II worm-like muscles. As a result, an attempt to clench the fingers into a fist leads to the fact that the II and III fingers remain straightened - a symptom of the "preacher's hand" (Fig. 19).

In addition, atrophy of the muscles of the elevation of the thumb, loss of the function of opposition of the first finger, and impaired flexion of the fingers are possible. Bringing the thumb to the index finger gives the hand a look that is designated as a symptom of the “monkey hand” (Fig. 20). In addition, on the palmar surface, the sensitivity of I, II, III fingers and the half of the IV finger adjacent to it falls out. On the back surface of the hand, skin sensitivity of the II, III and IV fingers suffers. Trophic disorders, cooling of the skin of the fingers, its dryness, peeling, cyanosis may appear. material from the site

Brachial plexus (plexusbrachialis) is formed from the anterior branches of the C5 Th1 spinal nerves (Fig. 8.3).

The spinal nerves, from which the brachial plexus is formed, leave the spinal canal through the corresponding intervertebral foramina, passing between the anterior and posterior intertransverse muscles. The anterior branches of the spinal nerves, connecting with each other, first form 3 trunks (primary bundles) of the brachial plexus that make it up

Fig- 8.3. Shoulder plexus. I - primary upper beam; II - primary middle beam; III - primary lower bundle; P - secondary posterior bundle; L - secondary outer beam; M - secondary internal beam; 1 - musculocutaneous nerve; 2 - axillary nerve; 3 - radial nerve; 4 - median nerve; 5 - ulnar nerve; 6 - internal cutaneous nerve; 7 - internal cutaneous nerve of the forearm.

supraclavicular part, each of which, by means of white connecting branches, is connected to the middle or lower cervical vegetative nodes.

1. Upper stem arises from the connection of the anterior branches of the C5 and C6 spinal nerves.

2. Medium trunk is a continuation of the anterior branch of the C7 spinal nerve.

3. lower trunk consists of the anterior branches of C8, Th1 and Th2 spinal nerves.

The trunks of the brachial plexus descend between the anterior and middle scalene muscles above and behind the subclavian artery and pass into the subclavian part of the brachial plexus, located in the zone of the subclavian and axillary fossae.

At the subclavian level each of the trunks (primary bundles) of the brachial plexus is divided into anterior and posterior branches, from which 3 bundles (secondary bundles) are formed that make up the subclavian part of the brachial plexus and named depending on their location relative to the axillary artery (a.axillaris), which they surround.

1. Back beam It is formed by the fusion of all three posterior branches of the trunks of the supraclavicular part of the plexus. From him begin axillary and radial nerves.

2. Lateral bundle make up the joined anterior branches of the upper and partially middle trunks (C5 C6 I, C7). From this bundle originate musculocutaneous nerve and part(outer leg - C7) median nerve.

3. Medial bundle is a continuation of the anterior branch of the lower primary bundle; from it are formed ulnar nerve, cutaneous medial nerves of the shoulder and forearm, as well as part of the median nerve(internal pedicle - C8), which connects to the external pedicle (in front of the axillary artery), together they form a single trunk of the median nerve.

Nerves formed in the brachial plexus belong to the nerves of the neck, shoulder girdle and arm.

Nerves of the neck. Short muscle branches are involved in the innervation of the neck. (rr.musculares), innervating deep muscles: transverse muscles (mm.intertrasversarif); long muscle of the neck (m.longuscolli), tilting the head to its side, and with the contraction of both muscles - tilting it forward; front, middle and back scalene muscles (mm.scalenianterior,medium,posterior), which, with a fixed chest, tilt the cervical spine to their side, and with a bilateral contraction, tilt it forward; if the neck is fixed, then the scalene muscles, contracting, raise the 1st and 2nd ribs.

Nerves of the shoulder girdle. The nerves of the shoulder girdle originate from the supraclavicular part of the brachial plexus and are primarily motor in function.

1. Subclavian nerve (p. subclavius, C5-C6) innervates the subclavian muscle (t.subclavius) which, when contracted, displaces the clavicle down and medially.

2. Anterior pectoral nerves (pp. thoracales anteriores, C5— Th1) innervates the pectoralis major and minor muscles (tt.pectoralesmajoretminor). The contraction of the first of them causes the adduction and rotation of the shoulder inward, the contraction of the second - the displacement of the scapula forward and downward.

3. Suprascapular nerve (n. suprascapular, C5-C6) innervates supraspinatus and infraspinatus muscles (t.supraspinatusetc.infraspinatus); the first contributes

abduction of the shoulder, the second - rotates it outward. Sensitive branches of this nerve innervate the shoulder joint.

4. Subscapular nerves (pp. subscapulars, C5— C7) innervate the subscapularis muscle (t.subscapularis), rotating the shoulder inward, and a large round muscle (t.teresmajor), which rotates the shoulder inward (pronation), takes it back and leads to the trunk.

5. Posterior nerves of the chest(nn,toracaiesposteriores): dorsal nerve of the scapula (P.dorsalisscapulae) and long thoracic nerve (P.thoracalislongus,C5—C7) innervates the muscles, the contraction of which ensures the mobility of the scapula (t.levatorscapulae, i.e.rhomboideus,m.serratusanterior). The last of them helps to raise the hand above the horizontal level. The defeat of the posterior nerves of the chest leads to asymmetry of the shoulder blades. When moving in the shoulder joint, the winged shape of the scapula on the side of the lesion is characteristic.

6. thoracic nerve (p. thoracodorsal, C7-C8) innervates the latissimus dorsi muscle (t.latissimusdorsi), which brings the shoulder to the body, pulls it back to the midline and rotates inward.

Nerves of the hand. The nerves of the hand are formed from the secondary bundles of the brachial plexus. The axillary and radial nerves are formed from the posterior longitudinal bundle, the musculocutaneous nerve and the external pedicle of the median nerve are formed from the external secondary bundle; from the secondary internal bundle - the ulnar nerve, the internal leg of the median nerve and the medial cutaneous nerves of the shoulder and forearm.

1. Axillary nerve (p. axillaris, C5— C7) — mixed; innervates deltoid muscle (t.deltoideus), which, when contracted, abducts the shoulder to a horizontal level and pulls it back or forward, as well as the small round muscle (t.teresminor), rotating the shoulder outward.

Sensory branch of the axillary nerve - superior external cutaneous nerve of the shoulder (P.cutaneusbrachiilateralissuperior)- innervates the skin above the deltoid muscle, as well as the skin of the outer and partly posterior surface of the upper part of the shoulder (Fig. 8.4).

With damage to the axillary nerve, the arm hangs like a whip, the removal of the shoulder to the side forward or backward is impossible.

2. Radial nerve (n. radialis, C7 partly C6, C8, Th1) - mixed; but mainly motor, innervates mainly the extensor muscles of the forearm - the triceps muscle of the shoulder (t.tricepsbrachii) and elbow muscle (t.apponens), extensors of the hand and fingers - long and short radial extensors of the wrist (tt.extensorcarpiradialislongusetbrevis) and finger extensor (t.extensordigitorum), forearm support (t.supinator), brachioradialis muscle (t.brachioradialis), involved in flexion and pronation of the forearm, as well as the muscles surrounding the thumb (tt.abductorpollicislongusetbrevis), short and long extensors of the thumb (tt.extensorpollicisbrevisetlongus), index finger extensor (t.extensorindicis).

Sensory fibers of the radial nerve make up the posterior cutaneous branch of the shoulder (P.cutaneusbrachiiposteriores), providing sensitivity to the back of the shoulder; inferior lateral cutaneous nerve of the arm (P.cutaneusbrachiilateralisinferior), innervating the skin of the lower outer part of the shoulder, and the posterior cutaneous nerve of the forearm (P.cutaneusantebrachiiposterior), determining the sensitivity of the back surface of the forearm, as well as the superficial branch (ramussuperficialis), involved in the innervation of the back surface of the hand, as well as the back surface of the I, II and half of the III fingers (Fig. 8.4, Fig. 8.5).

Rice. 8.4. Innervation of the skin of the surface of the hand (a - dorsal, b - ventral). I - axillary nerve (its branch - the external cutaneous nerve of the shoulder); 2 - radial nerve (posterior cutaneous nerve of the shoulder and posterior cutaneous nerve of the forearm); 3 - musculocutaneous nerve (external cutaneous nerve of the forearm); 4 - internal cutaneous nerve of the forearm; 5 - internal cutaneous nerve of the shoulder; 6 - supraclavicular nerves.

Rice. 8.5. Innervation of the skin of the hand.

1 - radial nerve, 2 - median nerve; 3 - ulnar nerve; 4 - external nerve of the forearm (branch of the musculocutaneous nerve); 5 - internal cutaneous nerve of the forearm.

Rice. 8.6. Hanging brush with damage to the radial nerve.

Rice. 8.7. The test of dilution of the palms and fingers in case of damage to the right radial nerve. On the side of the lesion, bent fingers “glide” along the palm of a healthy hand.

A characteristic sign of a lesion of the radial nerve is a hanging brush, located in the position of pronation (Fig. 8.6). Due to paresis or paralysis of the corresponding muscles, extension of the hand, fingers and thumb, as well as supination of the hand with an extended forearm, are impossible; the carporadial periosteal reflex is reduced or not elicited. In the case of a high lesion of the radial nerve, the extension of the forearm is also impaired due to paralysis of the triceps muscle of the shoulder, while the tendon reflex from the triceps muscle of the shoulder is not caused.

If you attach your palms to each other, and then try to spread them, then on the side of the lesion of the radial nerve, the fingers do not straighten, sliding along the palmar surface of a healthy hand (Fig. 8.7).

The radial nerve is very vulnerable; in terms of the frequency of traumatic lesions, it ranks first among all peripheral nerves. Especially often damage to the radial nerve occurs with fractures of the shoulder. Often, infections or intoxications, including chronic alcohol intoxication, are also the cause of damage to the radial nerve.

3. Musculocutaneous nerve (p. musculocutaneus, C5-C6) - mixed; motor fibers innervate the biceps brachii muscle (t.bicepsbrachii), flexing arm at the elbow joint and supinating the bent forearm, as well as the shoulder muscle (t.brachialis)y involved in the flexion of the forearm, and the coracobrachialis muscle (t.coracobrachial^^ contributing to raising the shoulder anteriorly.

Sensory fibers of the musculocutaneous nerve form its branch - the external cutaneous nerve of the forearm (P.cutaneusantebrachiilateralis), providing sensitivity of the skin of the radial side of the forearm to the elevation of the thumb.

With damage to the musculocutaneous nerve, flexion of the forearm is disturbed. This is especially evident with the supinated forearm, since flexion of the pronated forearm is possible due to the brachioradialis muscle innervated by the radial nerve. (t.brachioradialis). Also characteristic is the loss

tendon reflex from the biceps of the shoulder, raising the shoulder anteriorly. Sensitivity disorder can be detected on the outer side of the forearm (Fig. 8.4).

4. median nerve (p. medianus ) - mixed; is formed from a part of the fibers of the medial and lateral bundle of the brachial plexus. At shoulder level, the median nerve does not give branches. Muscular branches extending from it to the forearm and hand (ramimusculares) innervates the round pronator (t.pronatorteres), penetrating the forearm and contributing to its flexion. flexor carpi radialis (t.flexorcarpiradialis) along with flexion of the wrist, it abducts the hand to the radial side and participates in flexion of the forearm. Long palmar muscle (t.palmarislongus) stretches the palmar aponeurosis and is involved in flexion of the hand and forearm. Superficial finger flexor (t.digitorumsuperficialis) flexes the middle phalanges of the II-V fingers, participates in the flexion of the hand. In the upper third of the forearm, the palmar branch of the median nerve departs from the median nerve (ramuspalmaris n.mediant). It passes in front of the interosseous septum between the long flexor of the thumb and the deep flexor of the fingers and innervates the long flexor of the thumb. (t.flexorpollicislongus), bending the nail phalanx of the thumb; part of the deep flexor of the fingers (t.flexordigitorumprofundus), bending the nail and middle phalanges of the II-III fingers and brush; square pronator (t.pronatorquadratus), penetrating the forearm and hand.

At the level of the wrist, the median nerve divides into 3 common palmar digital nerves. (pp.digitakspalmarescommunes) and their own palmar digital nerves (pp.digitakspalmaresproprii). They innervate the short muscle that abducts the thumb. (t.abductorpollicisbrevis), muscle that opposes the thumb (t.opponenspolicis), flexor thumb short (t.flexorpollicisbrevis) and I-11 vermiform muscles (mm.lumbricales).

Sensitive fibers of the median nerve innervate the skin in the area of ​​the wrist joint (its anterior surface), the eminence of the thumb (thenar), I, I, III fingers and the radial side of the IV finger, as well as the back surface of the middle and distal phalanges of the II and III fingers ( Fig. 8.5).

Damage to the median nerve is characterized by a violation of the ability to oppose the thumb to the rest, while the muscles of the elevation of the thumb atrophy over time. The thumb in such cases is in the same plane with the rest. As a result, the palm acquires a typical form for lesions of the median nerve, known as the “monkey hand” (Fig. 8.8a). If the median nerve is affected at the level of the shoulder, there is a disorder of all functions, depending on its condition.

To identify impaired functions of the median nerve, the following tests can be carried out: a) when trying to clench the hand into a fist, I, II, and partly III fingers remain extended (Fig. 8.86); if the palm is pressed against the table, then the scratching movement with the nail of the index finger fails; c) to hold a strip of paper between the thumb and forefinger due to the impossibility of bending the thumb, the patient brings the straightened thumb to the index finger - thumb test.

Due to the fact that the median nerve contains a large number of vegetative fibers, when it is damaged, trophic disorders are usually pronounced and more often than when any other nerve is damaged, causalgia develops, manifesting itself in the form of sharp, burning, diffuse pain.

Rice. 8.8. Damage to the median nerve.

a - "monkey brush"; b - when squeezing the hand into a fist, fingers I and II do not bend.

5. Ulnar nerve (n. ulnaris, C8— Th1) — mixed; it begins in the axilla from the medial bundle of the brachial plexus, descends parallel to the axillary and then the brachial artery and goes to the internal condyle of the humerus and, at the level of the distal part of the shoulder, passes along the groove of the ulnar nerve (sulcus nervi ulnaris). In the upper third of the forearm, branches depart from the ulnar nerve to the following muscles: ulnar flexor of the hand (t.flexorcarpiulnaris), flexor and adductor brush; medial part of the deep flexor of the fingers (t.flexordigitorumprofundus), bending the nail phalanx of the IV and V fingers. In the middle third of the forearm, the cutaneous palmar branch departs from the ulnar nerve (ramuscutaneuspalmaris), innervating the skin of the medial side of the palm in the area of ​​​​the elevation of the little finger (hypotenar).

On the border between the middle and lower thirds of the forearm, the dorsal branch of the hand is separated from the ulnar nerve (ramusdorsalismanus) and palmar branch of the hand (ramusvolarismanus). The first of these branches is sensitive, it goes to the rear of the hand, where it branches into the dorsal nerves of the fingers. (pp.digitalesdorsales), which end in the skin of the back surface of the V and IV fingers and the ulnar side of the III finger, while the nerve of the V finger reaches its nail phalanx, and the rest reach only the middle phalanges. The second branch is mixed; its motor part is directed to the palmar surface of the hand and at the level of the pisiform bone is divided into superficial and deep branches. The superficial branch innervates the short palmar muscle, which pulls the skin to the palmar aponeurosis, further it is divided into common and proper palmar digital nerves. (pp.digitalespa/marescommunisetproprii). The common digital nerve innervates the palmar surface of the fourth finger and the medial side of its middle and final phalanges, as well as the back side of the nail phalanx of the fifth finger. The deep branch penetrates deep into the palm, goes to the radial side of the hand and innervates the following muscles: (t.adductorpolicis), adductor V finger (t.abductor

digitiminimumf), flexing the main phalanx of the V finger, a muscle that opposes the V finger (t.opponensdigitiminimi) - she brings the little finger to the midline of the hand and opposes it; deep head of flexor thumb brevis (t.flexorpollicisbrevis); worm-like muscles (tt.lumbricales), muscles that flex the main and unbend the middle and nail phalanges of the II and IV fingers; palmar and dorsal interosseous muscles (tt.interosseipalmalesetdorsales), bending the main phalanges and at the same time extending the other phalanges of the II-V fingers, as well as the II and IV fingers from the middle (III) finger and the II, IV and V fingers leading to the middle one.

Sensitive fibers of the ulnar nerve innervate the skin of the ulnar edge of the hand, the back surface of the V and partly the IV fingers and the palmar surface of the V, IV and partly III fingers (Fig. 8.4, 8.5).

In cases of damage to the ulnar nerve due to developing atrophy of the interosseous muscles, as well as hyperextension of the main and flexion of the remaining phalanges of the fingers, a claw-like brush is formed, resembling a bird's paw (Fig. 8.9a).

To identify signs of damage to the ulnar nerve, the following tests can be carried out: a) when trying to clench the hand into a fist, V, IV, and partly III, the fingers bend insufficiently (Fig. 8.96); b) scratching movements with the nail of the little finger do not work out with the palm tightly pressed to the table; c) if the palm rests on the table, then spreading and bringing the fingers together are not successful; d) the patient cannot hold a strip of paper between the index and straightened thumbs. To hold it, the patient needs to sharply bend the terminal phalanx of the thumb (Fig. 8.10).

6. Cutaneous internal nerve of the shoulder (n. cutaneus brachii medialis, C8— Th1 — sensitive, departs from the medial bundle of the brachial plexus, at the level of the axillary fossa has connections with external skin branches (rr.cutanilaterales) II and III thoracic nerves (pp.thoracales) and innervates the skin of the medial surface of the shoulder to the elbow joint (Fig. 8.4).

Rice. 8.9. Signs of damage to the ulnar nerve: claw-shaped hand (a), when the hand is compressed into a fist V and IV, the fingers do not bend (b).

Rns. 8.10. Thumb test.

In the right hand, pressing a strip of paper is possible only with a straightened thumb due to its adductor muscle, innervated by the ulnar nerve (a sign of damage to the median nerve). On the left, the paper strip is pressed by the long muscle innervated by the median nerve, which flexes the thumb (a sign of damage to the ulnar nerve).

7. Cutaneous internal nerve of the forearm (p. cutaneus antebrachii medialis, C8-7 h2 ) - sensitive, departs from the medial bundle of the brachial plexus, in the axillary fossa is located next to the ulnar nerve, descends along the shoulder in the medial groove of its biceps muscle, innervates the skin of the inner surface of the forearm (Fig. 8.4).

Syndromes of lesions of the brachial plexus. Along with an isolated lesion of individual nerves emerging from the brachial plexus, damage to the plexus itself is possible. Plexus injury is called plexopathy.

Etiological factors of damage to the brachial plexus are gunshot wounds of the supraclavicular and subclavian regions, fracture of the clavicle, 1st rib, periostitis of the 1st rib, dislocation of the humerus. Sometimes the plexus is affected due to its overstretching, with a quick and strong abduction of the arm back. Damage to the plexus is also possible in a position where the head is turned in the opposite direction, and the hand is behind the head. Brachial plexopathy can be observed in newborns due to traumatic injury during complicated childbirth. Damage to the brachial plexus can also be caused by carrying weights on the shoulders, on the back, especially with general intoxication with alcohol, lead, etc. The cause of compression of the plexus can be an aneurysm of the subclavian artery, additional cervical ribs, hematomas, abscesses and tumors of the supraclavicular and subclavian region.

Total brachial plexopathy leads to flaccid paralysis of all muscles of the shoulder girdle and arm, while only the ability to “lift the shoulder girdle” can be preserved due to the preserved function of the trapezius muscle, innervated by the accessory cranial nerve and the posterior branches of the cervical and thoracic nerves.

In accordance with the anatomical structure of the brachial plexus, the syndromes of damage to its trunks (primary bundles) and bundles (secondary bundles) differ.

Syndromes of damage to the trunks (primary bundles) of the brachial plexus occur when the supraclavicular part of it is damaged, while syndromes of damage to the upper, middle and lower trunks can be distinguished.

I. Syndrome of lesions of the upper trunk of the brachial plexus (the so-called upper Erb-Duchenne brachial plexopathy> occurs when the anterior branches of the V and VI cervical spinal nerves or the part of the plexus in which these nerves join form (after passing between the scalene muscles) the upper trunk. This place is located 2-4 cm above the collarbone, approximately a finger's width behind the sternocleidomastoid muscle and is called Erb's supraclavicular point.

Upper brachial Erb-Duchenne plexopathy is characterized by a combination of signs of damage to the axillary nerve, long thoracic nerve, anterior thoracic nerves, subscapular nerve, dorsal nerve of the scapula, musculocutaneous and part of the radial nerve. Characterized by paralysis of the muscles of the shoulder girdle and proximal parts of the arm (deltoid, biceps, brachial, brachioradial muscles and arch support), impaired shoulder abduction, flexion and supination of the forearm. As a result, the hand hangs down like a whip, is adducted and pronated, the patient cannot raise his hand, bring his hand to his mouth. If the hand is passively supinated, it will immediately turn inward again. The reflex from the biceps muscle and the wrist (carporadial) reflex are not caused, while radicular-type hypalgesia usually occurs on the outer side of the shoulder and forearm in the dermatome zone C v -C VI. Palpation reveals pain in the supraclavicular Erb point. A few weeks after the defeat of the plexus, an increasing hypotrophy of the paralyzed muscles appears.

Erb-Duchenne brachial plexopathy often occurs with injuries, it is possible, in particular, when falling on an outstretched arm, it may be a consequence of plexus compression during prolonged stay with arms wound under the head. Sometimes it appears in newborns with pathological childbirth.

2. Syndrome of lesions of the middle trunk of the brachial plexus occurs when the anterior branch of the VII cervical spinal nerve is damaged. In this case, violations of the extension of the shoulder, hand and fingers are characteristic. However, the three-headed muscle of the shoulder, the extensor of the thumb and the long abductor of the thumb are not completely affected, since along with the fibers of the VII cervical spinal nerve, fibers that have come to the plexus along the anterior branches of V and VI also participate in their innervation. cervical spinal nerves. This circumstance is an important feature in the differential diagnosis of the syndrome of lesions of the middle trunk of the brachial plexus and selective lesions of the radial nerve. The reflex from the tendon of the triceps muscle and the wrist (carpo-radial) reflex are not called. Sensory disturbances are limited to a narrow band of hypalgesia on the dorsal surface of the forearm and the radial part of the dorsal surface of the hand.

3. Syndrome of defeat of the lower trunk of the brachial plexus (lower brachial plexopathy Dejerin-Klumpke) occurs when the nerve fibers entering the plexus along the VIII cervical and I thoracic spinal nerves are damaged, while signs of damage to the ulnar nerve and cutaneous internal nerves of the shoulder and forearm, as well as parts of the median nerve (its inner leg ). In this regard, with Dejerine-Klumke paralysis, paralysis or paresis of the muscles, mainly of the distal part of the arm, occurs. It suffers mainly from the ulnar part of the forearm and hand, where sensory disturbances and vasomotor disorders are detected. It is impossible or difficult to extend and abduct the thumb due to paresis of the short extensor of the thumb and the muscle that abducts the thumb innervated by the radial nerve, since the impulses going to these muscles

pass through the fibers that make up the VIII cervical and I thoracic spinal nerves and the lower trunk of the brachial plexus. Sensitivity on the arm is impaired on the medial side of the shoulder, forearm and hand. If, simultaneously with the defeat of the brachial plexus, the white connecting branches leading to the stellate node also suffer (ganglionstellatum), then possible manifestations of Horner's syndrome(narrowing of the pupil, palpebral fissure and mild enophthalmos. In contrast to the combined paralysis of the median and ulnar nerves, the function of the muscles innervated by the external leg of the median nerve is preserved in the syndrome of the lower trunk of the brachial plexus.

Dejerine-Klumke paralysis often occurs as a result of a traumatic lesion of the brachial plexus, but it may also be the result of compression by its cervical rib or Pancoast tumor.

Syndromes of damage to the bundles (secondary bundles) of the brachial plexus occur during pathological processes and injuries in the subclavian region and, in turn, are divided into lateral, medial and posterior bundle syndromes. These syndromes practically correspond to the clinic of the combined lesion of peripheral nerves that form from the corresponding bundles of the brachial plexus. The lateral bundle syndrome is manifested by a dysfunction of the musculocutaneous nerve and the superior pedicle of the median nerve, the posterior bundle syndrome is characterized by a dysfunction of the axillary and radial nerve, and the medial bundle syndrome is expressed by a dysfunction of the ulnar nerve, medial pedicle of the median nerve, medial cutaneous nerves of the shoulder and forearm. With the defeat of two or three (all) bundles of the brachial plexus, a corresponding summation of clinical signs occurs, characteristic of syndromes in which its individual bundles are affected.

The anterior branches of the V and VI cervical nerves merge and form the upper trunk of the brachial plexus, the VIII cervical and I-II thoracic - the lower, VII cervical nerve continues into the middle trunk.

The defeat of the entire brachial plexus is accompanied by flaccid atrophic paralysis and anesthesia of all kinds on the upper limb. Disappear biceps, triceps, and carporadial reflexes. The scapular muscles are also paralyzed, Bernard-Horner syndrome is observed.

In clinical practice, one of the trunks of the brachial plexus is often affected.

Defeat superior trunk of the brachial plexus leads to paralysis of the proximal arm, deltoid, biceps, brachial, supra- and infraspinatus, subscapular, anterior serratus muscles are involved. The function of the hand and fingers is preserved. The biceps reflex is lost, the carpo-radial reflex is reduced. Sensitivity is detuned along the outer surface of the shoulder and forearm in the zone of roots CV-CVI. This clinical picture is called Duchenne-Erb palsy.

When defeated lower trunk of the brachial plexus (Dejerine-Klumpke palsy) the distal sections of the upper limb suffer (flexors of the hand and fingers, interosseous and other small muscles). Sensitivity drops out in the zone of roots СVIII-DII (the inner surface of the hand, forearm and shoulder). With high damage to the roots, the symptom of Bernard - Horner joins on the same side.

Defeat middle trunk of the brachial plexus manifested by paralysis of the extensors of the fingers and hand, flexors of the hand, round pronator. Anesthesia is localized along the dorsal surface of the hand in the area of ​​the CVII root.

In the subclavian fossa, depending on the topographic relationship with a. Axillaris trunks of the brachial plexus are named: lateral, posterior and medial. Below them, peripheral nerves are formed, the main among them are the radial, ulnar and median.

radial nerve(n.radialis). It is formed by the fibers of the CVII root (partially CV-CVIII, DI) and is a continuation of the posterior (middle) trunk of the brachial plexus. Its motor fibers innervate the following muscles: the triceps of the shoulder, the ulnar, radial and ulnar extensors of the wrist, the extensor of the fingers, the arch support of the forearm, the long abducent thumb and the brachioradialis. When the radial nerve is damaged, the extension of the forearm, the extension of the hand and fingers are disturbed, a "hanging" hand appears, and the thumb cannot be abducted. The following test is used: when unbending the hands folded together with fingers straightened so that the wrists continue to touch, the fingers of the affected hand do not move away, but bend and, as it were, glide over the palm of a healthy hand. The triceps reflex disappears and the carpo-radial reflex decreases. In addition to movement disorders, if this nerve is damaged, sensitivity is disturbed on the dorsal surface of the shoulder, forearm, hand, thumb and forefinger. Joint-muscular feeling is not affected.

Approximately in the middle of the shoulder, the radial nerve is adjacent to the bone. It is at this level that the nerve can be compressed during sleep. The ischemic lesion of the nerve that occurs under these conditions is called "sleepy" neuritis.

Ulnar nerve ( n . ulnaris) starts from the medial (lower) trunk of the brachial plexus (roots CVII, CVIII, DI). At the level of the medial epicondyle of the shoulder, the nerve passes under the skin and can be felt here. When this area is traumatized, paresthesias can occur in the form of a sensation of an electric current in the area of ​​​​the end of the skin branches of the nerve (ulnar side of the hand and V finger, medial surface of the fourth). In the same area, anesthesia occurs with a complete interruption of the nerve. The motor fibers of the ulnar nerve supply the following muscles: ulnar flexor of the hand, deep flexor of the IV, V fingers, short palmar, all interosseous, III and IV vermiform, adductor I finger of the hand and deep head of the short flexor of the first finger.

If the ulnar nerve is damaged, paralysis and atrophy of the muscles listed above develop: the interosseous spaces sink, the elevation of the fifth finger (hypothenar) flattens, the hand takes the form of a "clawed paw" (extension of the main phalanges and flexion of the middle and end, spreading fingers). The following tests can be applied:

a) when clenched into a fist, fingers V, IV and partially III fingers are not sufficiently bent;

b) the impossibility of bringing fingers, especially V and IV;

c) with a tightly pressed palm to the table, scratching movements of the terminal phalanx of the fifth finger are impossible;

d) thumb test: the patient grabs a strip of paper with the index and straightened thumbs of both hands and stretches it; on the side of the affected ulnar nerve, a strip of paper is not held (paralysis of the muscle that leads the thumb, m.adductor pollicis). To hold the paper, the patient flexes the terminal phalanx of the thumb (contraction of the flexor thumb, supplied by the median nerve).

Median nerve (n.medianus). It is formed by branches of the medial and lateral trunks of the brachial plexus (root fibers CV-CVIII, DI). The motor portion of the nerve supplies following muscles: radial flexor of the hand, long palmar, square pronator, I, II and III worm-like, deep and superficial flexor of the fingers, long flexor of the I finger, II and III interosseous, opposing and short abducting the I finger of the hand.

If the median nerve is damaged, the flexion of the hand, I, II, III fingers is weakened, the extension of the middle phalanges of II and III is impaired, pronation is disturbed, and opposition of the first finger is impossible.

Due to atrophy of the muscles of the elevation of the first finger (thenar), flattening of the palm occurs. This is aggravated by the fact that due to paralysis of m.opponens pollicis, the finger becomes in the same plane with the rest of the fingers. The palm acquires a peculiar flattened shape in the form of a spatula and resembles a monkey's hand.

To recognize movement disorders in the suffering of the median nerve, the following tests are used:

a) with a brush tightly pressed to the table, scratching bending of the terminal phalanges of the index finger is impossible;

b) when squeezing the hand into a fist, I, II and III fingers do not bend;

c) when testing the thumb, the patient cannot hold a strip of paper with a bent thumb, keeps it straight (due to the muscle that adducts the thumb; it is supplied by the ulnar nerve).

Sensitive fibers innervate the skin of the palmar surface of the I, II, III fingers and the radial side of the IV finger, as well as the skin of the rear of the terminal phalanges of these fingers. With damage to the median nerve in this area, anesthesia occurs and the articular-muscular feeling in the terminal phalanx of the II and III fingers is lost.

With nerve damage, especially partial, pain with causalgia features, as well as vasomotor-trophic disorders (bluish-pale skin color, its atrophy, dullness and brittleness, striated nails) can occur.

Damage to the brachial plexus, manifested by pain syndrome in combination with motor, sensory and autonomic dysfunction of the upper limb and shoulder girdle. The clinical picture varies depending on the level of the plexus lesion and its genesis. Diagnosis is carried out by a neurologist in conjunction with other specialists, it may require electromyo- or electroneurography, ultrasound, radiography, CT or MRI of the shoulder joint and plexus area, blood biochemistry, C-reactive protein levels and RF. It is possible to cure brachial plexitis and fully restore the function of the plexus only during the first year, provided that the cause of the disease is eliminated, adequate and complex therapy and rehabilitation are carried out.

General information

The brachial plexus is formed by branches of the lower cervical spinal nerves C5-C8 and the first thoracic root Th1. Nerves emanating from the brachial plexus innervate the skin and muscles of the shoulder girdle and the entire upper limb. Clinical neurology distinguishes between a total lesion of the plexus - Kerer's palsy, a lesion of only its upper part (C5-C8) - proximal Duchenne-Erb palsy and a lesion of only the lower part (C8-Th1) - distal Dejerine-Klumpke palsy.

Depending on the etiology, shoulder plexitis is classified as post-traumatic, infectious, toxic, compression-ischemic, dysmetabolic, autoimmune. Among plexitis of other localization (cervical plexitis, lumbosacral plexitis), brachial plexitis is the most common. The wide distribution and polyetiology of the disease determines its relevance for both neurologists and specialists in the field of traumatology-orthopedics, obstetrics and gynecology, rheumatology, toxicology.

Causes

Among the factors that cause shoulder plexitis, injuries are the most common. Damage to the plexus is possible with a fracture of the clavicle, dislocation of the shoulder (including habitual dislocation), sprain or damage to the tendons of the shoulder joint, bruising of the shoulder, cut, stab or gunshot wounds to the area of ​​the brachial plexus. Often, shoulder plexitis occurs against the background of chronic microtraumatization of the plexus, for example, when working with a vibrating instrument, using crutches. In obstetric practice, Duchenne-Erb obstetric palsy is well known, which is a consequence of birth trauma.

The second place in prevalence is occupied by brachial plexitis of compression-ischemic origin, which occurs when the plexus fibers are compressed. This can happen when the arm is in an uncomfortable position for a long time (during sound sleep, in bed patients), when the plexus is compressed by an aneurysm of the subclavian artery, a tumor, a post-traumatic hematoma, enlarged lymph nodes, an additional cervical rib, with Pancoast cancer.

Shoulder plexitis of infectious etiology is possible against the background of tuberculosis, brucellosis, herpetic infection, cytomegaly, syphilis, after influenza, tonsillitis. Dysmetabolic shoulder plexitis can occur with diabetes mellitus, dysproteinemia, gout, etc., metabolic diseases. It is not excluded iatrogenic damage to the brachial plexus during various surgical interventions in the area of ​​its location.

Symptoms

Shoulder plexitis manifests as a pain syndrome - plexalgia, which is shooting, aching, drilling, breaking. The pain is localized in the region of the collarbone, shoulder and spreads to the entire upper limb. Increased pain is observed at night, provoked by movements in the shoulder joint and arm. Then muscle weakness in the upper limb joins and progresses to plexalgia.

For Duchenne-Erb paralysis, hypotonia and a decrease in strength in the muscles of the proximal arm are typical, leading to difficulty in movements in the shoulder joint, abduction and raising of the arm (especially if it is necessary to hold a load in it), bending it in the elbow joint. Dejerine-Klumpke paralysis, on the contrary, is accompanied by weakness of the muscles of the distal parts of the upper limb, which is clinically manifested by difficulty in performing hand movements or holding various objects in it. As a result, the patient cannot hold the cup, use the cutlery fully, fasten the buttons, open the door with the key, etc.

Movement disorders are accompanied by a decrease or loss of the elbow and carporadial reflexes. Sensory disorders in the form of hypesthesia affect the lateral edge of the shoulder and forearm with proximal paralysis, the inner region of the shoulder, forearm and hand - with distal paralysis. With damage to the sympathetic fibers included in the lower part of the brachial plexus, one of the manifestations of Dejerine-Klumpke's paralysis may be Horner's symptom (ptosis, pupil dilation and enophthalmos).

In addition to motor and sensory disorders, brachial plexitis is accompanied by trophic disorders that develop as a result of dysfunction of peripheral autonomic fibers. Pastosity and marbling of the upper limb, increased sweating or anhidrosis, excessive thinning and dryness of the skin, increased brittleness of the nails are noted. The skin of the affected limb is easily injured, the wounds do not heal for a long time.

Often there is a partial lesion of the brachial plexus with the occurrence of either proximal Duchenne-Erb palsy or distal Dejerine-Klumpke palsy. More rarely, total brachial plexitis is noted, which includes the clinic of both listed paralysis. In exceptional cases, plexitis is bilateral, which is more typical for lesions of an infectious, dysmetabolic, or toxic origin.

Diagnostics

The neurologist can establish the diagnosis of "brachial plexitis" according to the anamnesis, complaints and examination results, confirmed by an electroneurographic study, and in its absence, by electromyography. It is important to distinguish plexitis from brachial plexus neuralgia. The latter, as a rule, manifests itself after hypothermia, is manifested by plexalgia and paresthesia, and is not accompanied by motor disorders. In addition, shoulder plexitis should be differentiated from polyneuropathy, mononeuropathies of the nerves of the arm (median nerve neuropathy, ulnar nerve neuropathy and radial nerve neuropathy), pathology of the shoulder joint (arthritis, bursitis, arthrosis), humeroscapular periarthritis, sciatica.

For the purpose of differential diagnosis and establishing the etiology of plexitis, if necessary, a consultation of a traumatologist, orthopedist, rheumatologist, oncologist, infectious disease specialist is carried out; Ultrasound of the shoulder joint, X-ray or CT scan of the shoulder joint, MRI of the brachial plexus, X-ray of the lungs, examination of blood sugar levels, biochemical blood tests, determination of RF and C-reactive protein, etc. examinations.

Treatment

Differentiated therapy is determined by the genesis of plexitis. According to the indications, antibiotic therapy, antiviral treatment, immobilization of the injured shoulder joint, removal of a hematoma or tumor, detoxification, correction of metabolic disorders are carried out. In some cases (more often with obstetric paralysis), a joint decision with the neurosurgeon is required on the advisability of surgical intervention - plasty of the nerve trunks of the plexus.

The general direction in treatment is vasoactive and metabolic therapy, which provides improved nutrition, and hence the speedy recovery of nerve fibers. Patients with shoulder plexitis receive pentoxifylline, complex preparations of B vitamins, nicotinic acid, ATP. Some physiotherapy procedures are also aimed at improving the trophism of the affected plexus - electrophoresis, mud therapy, thermal procedures, and massage.

Equally important is the symptomatic therapy, including the relief of plexalgia. Patients are prescribed NSAIDs (diclofenac, metamizole sodium, etc.), therapeutic blockades with novocaine, hydrocortisone ultraphonophoresis, UHF, reflexology. To support muscles, improve blood circulation and prevent contractures of the joints of the affected arm, a special exercise therapy complex and massage of the upper limb are recommended. In the recovery period, repeated courses of neurometabolic therapy and massage are carried out, exercise therapy is continuously carried out with a gradual increase in load.

Forecast and prevention

Timely initiation of treatment, successful elimination of the causative trigger (hematomas, tumors, injuries, infections, etc.), adequate restorative therapy usually contribute to the complete restoration of the function of the nerves of the affected plexus. With a belated start of therapy and the inability to completely eliminate the influence of the causative factor, shoulder plexitis has a not very favorable prognosis in terms of recovery. Over time, irreversible changes occur in muscles and tissues caused by their insufficient innervation; muscular atrophy, joint contractures are formed. Since the dominant hand is most often affected, the patient loses not only his professional capabilities, but also his ability to self-service.

Measures to prevent shoulder plexitis include injury prevention, an adequate choice of the method of delivery and professional management of childbirth, compliance with operating techniques, timely treatment of injuries, infectious and autoimmune diseases, and correction of dysmetabolic disorders. Compliance with a normal regimen, healthy physical activity, and proper nutrition help to increase the resistance of nerve tissues to various adverse effects.