Which major nerve in the brachial plexus was damaged. Traumatic brachial plexus injury

When brachial plexus injury a group of nerves that transmit signals from the spinal cord to the shoulder, forearm and hand are affected. Brachial plexus injury is a sprain or, in the worst case, a complete rupture of these nerves. This injury occurs when a downward force is exerted on the shoulder and an upward and outward force on the head.

Brachial plexus injuries are common in contact sports, road accidents involving motor vehicles and motor vehicles, and falls. In babies, the brachial plexus can be damaged by birth trauma. The brachial plexus can also be affected by other conditions, such as inflammatory processes or neoplasms.

Minor injuries can go away on their own, but more severe cases require surgery.

Symptoms

Signs and symptoms of brachial plexus injury vary greatly depending on the severity and location of the injury. Usually only one hand is affected.

Minor injuries

Minor injuries, i.e. sprains of the nerves, usually occur during contact sports such as football or wrestling. These injuries are characterized by the following symptoms:

• Feeling like an electric shock or burning sensation in the hand
• Numbness and weakness in the arm
• Symptoms usually last a few seconds or minutes, but some people may have symptoms that last for several days or longer.

More severe injuries

More severe symptoms usually occur when nerves are broken or severed. The most severe injury to the brachial plexus is avulsion, that is, the separation of the nerve root from the spinal cord.

Signs and symptoms of more severe injuries include:

• Ability to wiggle fingers, but loss of control of the muscles in the shoulder and elbow
• Ability to control the hand, but not the fingers
• Complete loss of control of the arm, including the elbow and wrist
• Severe pain

Conditions under which you need to see a doctor

Severe trauma to the brachial plexus can lead to disability. Even if the injury seems minor, you should see a doctor. A doctor should be consulted if:

• Burning or tingling sensation occurs periodically
• Weakness in the arm or hand
• Weakness anywhere in the arm after injury
• Pain in the neck
• Spreading symptoms to both hands
• Spread of symptoms to arms and legs

Complications

Over time, most brachial plexus injuries in adults and children heal without permanent damage. However, some injuries can cause temporary or permanent disruption:

Joint stiffness. With paralysis of the arm or hand, joint stiffness can occur, which can limit the mobility of the joints, although control of the limb is restored. To do this, doctors usually prescribe physical therapy classes during the recovery period.
Pain... The pain is due to nerve damage and can become chronic.
Loss of sensitivity. If you lose sensation in your hand or hand, there is a risk of accidentally injuring or burning it and not notice it.
Muscle atrophy... Nerves regenerate slowly over several years. During this time, muscles that are not subjected to sufficient stress may atrophy.
Irreversible violations... Recovery from brachial plexus injury depends on a number of factors, including age, type, location, and severity of the injury. Even after surgery, some patients experience irreversible disorders, ranging from weakness in the hand, shoulder, or forearm to paralysis.

This site is intended for persons over 18 years of age, contains a number of photos and videos that are not intended for viewing by persons with an unprepared psyche.

Site materials are for informational purposes only. To make the correct diagnosis and choose further treatment tactics, a specialist consultation is required.

Brachial plexus injuries
Mechanisms of injury Diagnosis Symptoms
Surgery

Brachial plexus injuries are among the most severe and prognostically unfavorable diseases of the peripheral nerves. The severity of this pathology for the patient is due to disability, pain, cosmetic defect, and decreased social adaptation.

There are several mechanisms of brachial plexus injury:

1. Shoulder impact of the body, which has a reserve of kinetic energy, on a stationary object, which in turn leads to tension of the trunks between the clavicle, the intervertebral foramen and the head humerus... If the rupture of the trunks occurs distal to the exit of the trunks from the intervertebral foramen, then the prognosis for the restoration of hand functions is quite favorable, but if we are dealing with preganglionic detachment, then, unfortunately, recovery will not occur.

2. When falling from a small height onto the arm, traction damage to the trunks occurs as a result of their tension between one rib, the clavicle and the head of the humerus. Such injuries rarely lead to preganglionic injuries, therefore, in prognostic terms, they are more favorable.

3. Traction injuries due to blows with a vector directed from top to bottom on the shoulder. In this situation, the forecast depends on the force of the blow.

4. Damage to the brachial plexus trunks by stabbing and cutting objects.

5. Damage to the brachial plexus trunks as a result of gunshot and mine-explosive wounds.

The brachial plexus is formed from 5,6,7,8 cervical and 1,2 thoracic roots. 5 and 6 roots form the upper primary trunk, 7 cervical root forms - middle, 8 cervical, 1 and 2 chest - form the lower trunk of the brachial plexus.
All primary trunks are divided into anterior and posterior branches, from which secondary trunks are formed. The fusion of the posterior branches forms the posterior secondary trunk, which gives rise to the axillary and radial nerves. From the anterior branches of the upper and middle trunks, a lateral trunk is formed, giving rise to the musculocutaneous nerve and the lateral pedicle of the median nerve. From the anterior branch of the lower primary trunk, the ulnar and partially the median nerves, the internal nerves of the shoulder and forearm, are formed.

Topical diagnosis is based on the structural features of the brachial plexus trunks.

The defeat of all trunks causes a syndrome of total conduction disturbance, including paralysis of all muscles of the arm, anesthesia of the skin on the entire surface of the arm, Horner's syndrome (constriction of the pupil, palpebral fissure and retraction eyeball), pain syndrome also often joins.

If the upper trunk is damaged, the patient will have violations of shoulder elevation and flexion in the elbow joint, and a loss of the tendon reflex of the biceps of the shoulder is also observed.

The defeat of the lower trunk of the brachial plexus leads to dysfunction of the muscles of the hand, flexors of the hand, fingers. At the same time, the functions of the circular pronator and radial flexor of the hand are preserved.

Isolated damage to the middle primary trunk leads to partial loss of functions of the radial nerve, with the exception of the brachioradial muscle, the source of innervation of which is the upper primary trunk.

Surgery brachial plexus injuries

Surgical tactics are planned based on the level and severity of injuries.
All injuries can be divided into preganglionic and postganglionic.

For preganglionic separation (avulsion) of the brachial
plexus is characterized by the following diagnostic criteria:

• horner's syndrome
• paralysis, anesthesia, atrophy of the muscles innervated by the damaged trunk
• the presence of an intramedullary cyst in the area of \u200b\u200bthe cervical thickening in the projection of the damaged trunk
• changes on EMG: signs of complete denervation of muscle fibers with good preservation of sensory responses
• the presence of persistent pain syndrome, not relieved by analgesics

The presence of meningocele is not a sign of preganglionic avulsion.

Stages of the operation for the reinnervation of the musculocutaneous nerve with an accessory using autotransplant. The arrows show the places of the autograft sutures with the musculocutaneous and accessory nerves.

Postganglionic damage is characterized by:

• Absence of complete conduction disturbance syndrome
• positive dynamics during the first 3-6 months after injury
• pain syndrome is either absent or of low intensity, within 4 - 12 months undergoes positive dynamics
• absence of intramedullary cysts on MRI
• soreness of the trunks on palpation

Muscle paralysis may occur, but as a rule, positive dynamics will be observed within 4-6 months.

Fortunately, complete preganglionic avulsion of all trunks is very, very rare. More often one trunk suffers, while others will be partially preserved. With preganglionic detachment, reinnervation of the damaged trunk is shown. Accessory or intercostal nerves are most often taken as a donor. It should be noted that full-fledged reinnervation of the trunk by a thin nerve is impossible, therefore, the long-term results of such operations are controversial.

With postganglionic injuries, neurolysis and endoneurolysis of the brachial plexus trunks are performed.

In case of irreparable damage to the brachial plexus trunks, orthopedic operations are performed. The indications for these operations and the technique of execution are described in great detail and brilliantly in the works of prof. NA Ovsyankina "Surgical treatment of children with consequences of injury to the brachial plexus". Anyone who is interested, I highly recommend reading it.

• Peripheral nerve damage

The brachial plexus is formed from axons,
outgoing from the roots C5 - Th1 (sometimes C4 and Th2), which
leads to mixed innervation of the muscles of the shoulder
belts and upper limbcomplicating accurate
diagnostics.

Most common reasons traumatic
brachial plexus lesions: road traffic accidents, straight blunt
blows in the supraclavicular and subclavian regions,
anterior dislocation of the humerus head, stab and
gunshot wounds, falling on an outstretched hand,
clavicle fracture, prolonged compression, etc.

The defeat of the primary trunks of the brachial plexus:

Duchenne-Erb paralysis.
- paralysis of the Dejerine-Klumpke type.
- isolated lesion of individual nerve trunks.
- total defeat

Algorithm for diagnosing brachial plexus lesions:

Clinical picture
- X-ray, CT, MRI of the shoulder girdle
- electroneuromyography

Duchenne-Erb paralysis(upper primary trunk - C V - C VI roots )

Primary lesion of the muscles of the shoulder girdle.
Sometimes combined with a lesion of the middle primary trunk (C VII root) - suffer
extensors of the forearm and hand

Surgery - posterolateral approach (decompression, neurolysis, endoneurolysis and anti-adhesion protector installation)

Forecast: efficiency\u003e 50-70%

Fig. 1. Posolateral approach to the primary trunks of the brachial plexus

Dejerine-Klumpke paralysis(lower primary trunk - C VIII -D I roots)

Primary damage to the muscles of the forearm and hand.
Horner's syndrome: ptosis, miosis, enophthalmos. This is a bad predictive sign
indicating intradural separation of C VIII - D I roots from the spinal cord.

Surgery - angular access (decompression, neurolysis, endoneurolysis and
installation of anti-adhesion protector)

Forecast: efficiency\u003e 50-70%

(postganglionic )

Mechanism of injury - road accident (motorcycle injury), traction mechanisms

Flaccid plegia of the upper limb and muscle hypotrophy of the shoulder girdle and limb
(the hand hangs like a "lash", there are no active movements in all joints).
- violation of all types of sensitivity, constant pain in the arm

Surgery - combined approaches: posterior subscapular, posterolateral, angular (decompression, neurolysis, endoneurolysis and anti-adhesion protector installation)

Forecast: efficiency \u003d< 50%

Total defeat of the brachial plexus trunks(preganglionic )

The mechanism of injury - road accident (motorcycle injury), traction mechanisms.
- flaccid plegia of the upper limb and muscle hypotrophy of the shoulder girdle and limb.
- severe pain syndrome of a deafferent nature

Surgery - surgery to relieve pain syndrome DREZ

Forecast: regression of pain syndrome more than 90%

Fig. 2. Ultrasound myelotomy

Lesion of the secondary trunks of the brachial plexus

The mechanism of injury - road accident, fall; a blow to the collarbone and subclavian region; anterior dislocation of the shoulder; gunshot and stab wounds, radiation therapy after mastectomy

There are lesions of the posterior, external and internal secondary trunk or their various combinations in combination with vascular disorders.

The clinical picture depends on the affected structures

Surgery - angular access (decompression, neurolysis, endoneurolysis,
angiolysis and installation of an anti-adhesive film.

Fig. 3. Angled access to the secondary trunks of the brachial plexus

The prognosis depends on the volume of unaffected nerve structures

Damage proximal to the ganglion is preganglionic, and recovery is impossible. Damage distal to the ganglion is postganglionic and can be repaired.

The clavicle conditionally divides the plexus into two levels: supraclavicular injuries of the brachial plexus are distinguished (for example, a motorcycle traction injury) and subclavian (for example, with dislocation of the shoulder).

Causes of damage

Injury

• Typical for motorcyclists and falls from a height.
• Extension of the shoulder with side traction.
• Concomitant injury - root separation, traction injury of the spinal cord.
• Severe stretching also damages the subclavian artery (ruptures of the intima or artery).
• Can be easily damaged by dislocation of the shoulder (axillary, radial, musculocutaneous nerve).

Puncture wounds

• When removing axillary or supraclavicular lymph nodes
• Clavicle fracture
• When resecting the first rib.

Irradiation

The brachial plexus is located in the radiation zone of the breast and axillary cavity.

Clinical data

Injuries are associated with the transfer of significant energy, therefore, the likelihood of other systemic injuries (chest, pelvis, abdomen, spine) is high.

Hemorrhage in the shoulder joint or on the face.

Localization of damage

Establishing the level of damage by systematic examination of neurological function is aided by recording the data obtained in the form of a brachial plexus function diagram or a functional map. The damage is often mixed (tear and damage along the length), neuropraxia, axonotmesis, and neurotmesis. The anatomical distribution may change with recovery. Watch out for neurological deterioration - hematoma?

Separation of the C5 spine

• Loss of function of the rhomboid muscles and the long thoracic nerve.
• Impossibility of abduction and internal rotation in the shoulder joint. (C5 deltoid and suprascapular nerve).

Loss of sensitivity along the lateral surface of the shoulder joint and upper limb

Upper trunk (C5, C6)

• Preservation of the dorsal scapular nerve (C5 rhomboid), long thoracic nerve (C5, 6, 7 serratus anterior muscle)
• Movement disorders: abduction (axillary nerve, suprascapular nerve), external rotation (suprascapular nerve), flexion in the elbow joint (C5, C6 biceps muscle through the musculocutaneous nerve, brachioradial and brachial muscles through the radial nerve); supination (C6 biceps muscle through the musculocutaneous nerve, instep support through the radial nerve) pronation.
• Loss of sensitivity: lateral surface shoulder joint, shoulder, forearm and first toe.

Opening the roots of C7, C8 or damage to the lower trunk

• Rarely found. Weakness of the flexors of the fingers and hand, lack of function of the short muscles of the hand. Claw deformity of all fingers.
• Loss of sensitivity: elbow side of the shoulder, forearm and hand.

Damage to the entire brachial plexus

• Usually combined with vascular damage.
• Disorders: lack of all muscle function and sensitivity.

Pre- or postganglionic?

Preganglionic damage (root detachment) cannot be repaired.

Effects:

• Burning pain in an insensitive hand
• Paralysis of the scapular muscles
• Diaphragm paralysis
• Horner's syndrome: ptosis, miosis (narrow pupil), enophthalmos and anhidrosis.
• Severe vascular injury
• Combines with a fracture cervical spine
• Spinal cord dysfunction (eg, hyperreflexia in the lower extremities).
• Positive histamine test: intradermal administration of histamine usually causes a triple reaction of the surrounding skin (central expansion of capillaries, papules and inflammatory hyperemia). If hyperemia persists in the insensitive area of \u200b\u200bthe skin, then the damage is proximal to the posterior root ganglion.
• CT myelography or MRI may reveal pseudomeningocele caused by a tearing of the root
• Study of nerve conduction: Careful interpretation is needed. Sensory conduction from an insensitive dermatome indicates preganglionic injury (i.e., the nerve distal to the ganglion is intact). Reliable results can only be obtained after a few weeks, when Wallerian degeneration in postganglionic injury blocks nerve conduction.

Postganglionic injury

May recover (neuropraxia or axonotmesis) or recoverable.

Treatment

Priorities

• Resuscitation and treatment of life-threatening injuries are priority measures.
• Restoration of damaged vessels.
• Stabilization of combined skeletal injuries.
• Transfer to a specialized institution.

Open damage

Emergency intervention shown

High energy trauma

• Most often severe (grade 4 or 5).
• In the first week, the operation is much easier and the results are better after the early intervention.

Low Energy Closed Damage

More likely moderate severity damage (1 or 2 degrees) with the possibility of recovery. The observation period is justified. Since the degree of damage to the brachial plexus can vary, some muscles are likely to recover, but not all.

If recovery is progressing at the expected rate, continue monitoring.

Recovery done after 6 months is unlikely to be successful.

Surgical strategy

If one nerve root is preserved (for example, C5), plastic of the lateral bundle is performed, which provides flexion in the elbow joint, flexion of the fingers and sensitivity along the radial side of the hand.

If two roots are preserved (for example, C5, C6), they are connected to the lateral and posterior bundles.

Neurotization of the suprascapular nerve can be performed by anastomosing through the accessory spinal nerve insert.

Nerve plastics

Direct restoration of the nerve is possible only after transection, whereas with traction damage to the nerve, plastic is required.

Donor nerves

• Sural nerve
• Lateral cutaneous nerve of the forearm
• Ulnar nerve on the vascular pedicle (if there is a T1 avulsion).

Nerve transposition

When C5 and C6 are torn off, the spinal accessory nerve is transposed to the suprascapular nerve, or two or three intercostal nerves move to the musculocutaneous nerve.

Results of surgical interventions

The distance the nerve has to regenerate in the event of damage to the lower trunk / middle bundle means that axons will not have time to grow to the motor end plates and sensory receptors before muscle atrophy and loss of receptors.

A shorter distance for regeneration in the event of damage to the upper roots or trunk gives favorable results.

Therefore, primary repair or late reconstruction should be performed for C5 and C6 injuries to restore shoulder abduction, elbow flexion, wrist extension, finger flexion, and lateral (radial) hand sensitivity.

It takes two or three years for noticeable results to appear.

Three typical options

• Detachment or rupture of C5, 6, (7) with preservation of C (7) 8, T1: the most favorable outcome, since hand function (C8, T1) is preserved and early recovery or late reconstruction will provide an acceptable function of the muscles innervated by the upper roots.
• Rupture of C5, 6 (7) with separation of C7, 8, T1: movement in the shoulder and elbow joints may be restored with early recovery or late reconstruction, but hand function is usually not restored.
• C5-T1 gap: bad outcome. There are few donor axons suitable for upper neurotization, and hand function is usually not restored.

Late reconstruction

Best results after very early intervention. If the patient comes late after injury or after an unsuccessful intervention, reconstruction is indicated. Recovery of function is long and limited, but as Sterling Bunnell said "... for the one who has nothing and the smallest is already a lot."

Sequence

• Elbow flexion
• Shoulder abduction
• Capture (sensitivity and movement of the first and three-phalanx fingers).

Operational interventions:

Tendon transposition for flexion at the elbow

• Pectoralis major (Clarke transposition)
• Flexor attachment site (Steindler transposition)
• Latissimus dorsi
• Triceps.

The nerve that innervates these muscles must be intact, so they can only be used for certain types of damage.

Free muscle transplant

• 1 (spruce: restore flexion in the elbow joint and extension of the wrist, with irreversible muscle changes due to prolonged denervation.
• The gracilis, rectus femoris or latissimus dorsi on the opposite side can be grafted as a free flap and innervated by two or three intercostal nerves (with or without sural nerve plasty for lengthening), or an Oberlin transposition can be performed.

Nerve transposition (neurotization)

• Intercostal to biceps
• Sensitive intercostal to the lateral bundle (C5, C7)
• The opposite root, C7, is lengthened with nerve trunk grafts.
• Spinal accessory nerves
• Blood-supplied ulnar nerve

Shoulder arthrodesis

Indication: An unstable or painful shoulder joint. After unsuccessful reinnervation of the supraspinatus muscle. There is no ideal position, they are selected individually.

Injury to individual peripheral nervesand nerve plexuses.

In pediatric practice, damage to the nerves of the brachial plexus, as a rule, is a consequence of pathologically proceeding childbirth.

Plexus brachialis (brachial plexus)

The brachial plexus is made up of fibers of the anterior branches of the 5, 6, 7, 8 cervical, 1, 2 thoracic spinal nerves. From the C5 and C6 spinal nerves, the upper trunk (truncus superior) of the brachial plexus is formed, the middle trunk (fruncus medius) is a continuation of the C7 spinal nerve and the lower trunk (truncus inferior) is formed from the fusion of the C8 and TI-T2 spinal nerves. The listed trunks of the brachial plexus are located in the supraclavicular fossa.

The defeat of the entire brachial plexus causes flaccid atrophic paralysis and anesthesia of the upper limb with loss of the extensor-ulnar, flexion-ulnar and carporadial reflexes. With high lesions of the plexus, a lesion of the scapular muscles and a symptom of Claude Bernard-Horner join.

The defeat of the C5-C6 spinal nerves or the upper trunk of the brachial plexus (Duchenne-Erb palsy) leads to the loss of the axillary (m. Deltoideus), musculocutaneous (mm. Biceps, brachialis) and only partially radial (mm. Brachioradialis, supinator) nerves function ... With radicular or very high lesions of the upper trunk, a loss of function and scapular muscles (mm. Supraspinatus, infmspinatus, subscapularis, serratus anterior) joins. The flexion-ulnar reflexes fade away and the carporadial reflexes may be weakened.

Thus, upper paralysis is characterized by damage to the proximal part of the upper limb while maintaining the function of the hand and fingers. In this case, the anesthetic zone is distributed according to the radicular (C5-C6) type on the outer surface of the shoulder and forearm.

The defeat of the C8-T2 spinal nerves or the primary lower trunk of the brachial plexus (Dejerine-Klumpke paralysis) causes a complete loss of the functions of the ulnar, internal cutaneous nerves of the shoulder and forearm and partial damage to the median nerve, its lower leg.

As a result, distal paralysis occurs with a predominant lesion and atrophy of the small muscles of the flexors of the fingers and hand, the so-called inferior plexus paralysis. With a high lesion before discharge rr. communicantes (sympathetic fibers going to the eye), Horner's symptom joins. Sensitivity is impaired by the radicular (C8-T2) type on the inner surface of the hand, forearm and shoulder.

The defeat of the C7-spinal nerve or the middle trunk of the plexus causes a significant loss of functions of the radial nerve and partly of the median nerve.

The trunks of the brachial plexus are further divided into anterior and posterior branches. From the front branches of the upper and middle trunks (C5, C6, C7), the outer bundle (fasciculus lalemlis) is formed. From the front branches of the lower trunk (C8, T2), an internal bundle (fasciculus medialis) is made up. Finally, from all the posterior branches of the primary trunks (C5, C6, C7, C8, Tl, T2), a posterior bundle (fasciculus posterior) is formed. The names of the bundles are due to their location relative to a. axillaris.

The bundles of the brachial plexus are located in the subclavian fossa; then they form the actual nerves of the upper limb: the external bundle - n. musculocutaneus and upper leg n. mediani; posterior bundle - n. axillaris et n. radialis and internal bundle - n. ulnaris, lower leg n. mediani, nn. cutanei brachii et antebrachii medialis.

The defeat of the external bundle of the brachial plexus causes a complete dysfunction of n. musculocutanei, partial - n. mediani (fibers of its upper leg, in particular m. pronator teres), and limited - n. radialis (mm. brachioradialis, supinator).

Thus, the similarity of the clinical picture of the lesion of the upper trunk of the brachial plexus and the lesion of the external bundle of the brachial plexus is the prolapse in both cases of the function of the cutaneous muscle nerve and the limited loss of the radial function.

The difference is that when the upper trunk of the brachial plexus is damaged, this combination also includes the loss of function n. axillaris, which does not suffer with damage to the external bundle of the brachial plexus, but in the latter case there is a partial defeat of n. mediani.

The defeat of the internal bundle of the brachial plexus and the defeat of the lower trunk of the brachial plexus give a similar clinical picture, that is, a combination of lesions n. ulnaris, nn. cutanei brachii et antebrachii mediales and partial defeat I. mediani (its lower leg). Horner's symptom in this case, as with a more distal lesion, is not observed.

Defeat posterior beam brachial plexus is characterized by a combination of lesions n. axillaris et n. radialis (except for preserved mm. brachioradialis, supinator). The similarity with the clinical picture of the lesion of the middle trunk of the brachial plexus consists in the same loss of function n. radialis. The difference is that when the middle trunk is affected, the function n. axillaris persists, but instead the function n is partially violated. mediani, its upper leg.

Thus, the fibers of the lower trunk of the brachial plexus pass into the internal bundle, which determines the similarity of the clinical picture when they are damaged. N. radialis, in its main function, suffers both when the middle trunk and the posterior bundle are damaged, but in the first case (middle trunk) - in combination with partial damage to n. mediani, and in the second (posterior bundle) - with a lesion n. axillaris.

Function n. axillaris falls out both when the upper trunk and the posterior bundle are damaged due to the corresponding transition of its fibers.

Finally, and. musculocutaneus suffers equally when the upper trunk and the external bundle are affected, but in the first case (upper trunk) - in combination with, n. axillaris, and in the second (lower bundle) with partial damage to n.mediani.

Nerves emanating from the brachial plexus.

1. axillaris (axillary nerve). The mixed nerve is made up of the fibers of the C5, C6 and C7-spinal nerves, passing first as part of the superior trunk, then the posterior bundle of plexus.

With damage to the C5-C6 spinal nerves or the superior trunk of the brachial plexus (in the supraclavicular fossa), as is observed in Erb's paralysis, the nerve suffers in combination with n. musculocutaneus.

With the defeat of the posterior bundle (in the subclavian fossa), function n. axillaris is violated together with n. radialis.

The motor fibers of the nerve innervate m. deltoideus (et m. teres minor), sensitive - the skin of the outer surface of the shoulder (n. cutanei brachii lateralis).

If n. axillaris, atrophy of the deltoid muscle is observed, the inability to raise the shoulder in the frontal plane to a horizontal line and impaired sensitivity on the skin of the outer surface of the shoulder.

1. musculocutaneus (musculocutaneous nerve). The nerve is mixed, it is also formed from the fibers of the C5-C6-C7-spinal nerves, passing through first the upper trunk, then the external bundle of the brachial plexus.

With the defeat of the C5-Sat of the spinal nerves or the superior trunk of the plexus (in the supraclavicular fossa), as is the case with Duchenne-Erb paralysis, it suffers in combination with n. axillaris.

With the defeat of the external bundle (in the subclavian fossa), the loss of function n. musculocutaneus is observed together with a partial defeat of I. mediani, its upper leg (weakening of pronation and palmar flexion of the hand).

The motor fibers of the nerve innervate m. biceps brachii (as well as m. brachialis et m. coracobrachialis), and sensitive - the skin of the outer (radial) surface of the forearm (n. cutanei anlebrachii lateralis).

If n. musculocutanei there is atrophy of m. bicipitis, the flexion-elbow reflex fades and the flexion of the forearm is significantly weakened (it is completely impossible in the pronation position, since in the supination position or in the middle between them, flexion in the elbow joint can be carried out due to the contraction of the brachioradialis m. innervated by n. radialis.

Disorders of sensitivity are observed on the outer (radial) surface of the forearm.

1. radialis (radial nerve). The mixed nerve arises mainly from the fibers of the C7-spinal nerves (partly from the C5, C6, C8 and T1), which first pass through the middle trunk, then the posterior bundle of the brachial plexus.

When the C7 spinal nerves or the middle trunk are affected, the main function of the nerve falls out (except for m.brachioradialis et m.supinator) in combination with a partial lesion of n.mediani, its upper leg (weakening of pronation and palmar flexion of the hand)

With the defeat of the posterior bundle of the brachial plexus, the same basic functions n fall out. radialis, but in combination with n. axillaris.

Motor fibers n. radialis is innervated by the extensors of the forearm (m. triceps et m. anconeus), hand (mm. extensores carpi radialis et carpi ulnares) and fingers (mm. extensores digitorum) the instep support of the forearm (m. supinator), the muscle abducting the thumb (m. abductor pollicis longus), etc. brachioradialis, which takes part in the flexion of the forearm. Sensory fibers innervate the skin of the posterior surface of the shoulder (n. Cutaneus brachii posterior), the dorsal surface of the forearm (n. Cutaneus antebrachii dorsalis), the radial side of the dorsum of the hand and partially I, II and sometimes III fingers.

With a high lesion n. radialis in the axillary fossa, in the upper third of the shoulder, paralysis of the extensors of the forearm, hand, main phalanges of the fingers, the muscle abducting the thumb of the instep support occurs; the flexion of the forearm (m. brachioradialis) is weakened. The reflex from the tendon of m. triceps and the carporadial reflex is somewhat weakened (due to switching off the contraction of m. brachioradialis). Sensitivity falls on the dorsal surface of the shoulder, forearm, partly the hand and fingers. The zone of sensory disorders on the hand is often significantly reduced due to the overlap of the zone by the innervation of neighboring nerves. The joint-muscular feeling is not affected. At lower levels of damage, the function of the nerve suffers limitedly, since the branching branches are preserved above, which facilitates the tasks of topical diagnosis.

With nerve damage, very frequent, at the level of the middle third of the shoulder, the function of extension of the forearm and the extensor-ulnar reflex (m. Triceps) is preserved and the sensitivity on the shoulder is not disturbed.

With a lesion in the lower third of the shoulder, the function of m may be preserved. brachioradialis and sensitivity on the dorsal surface of the forearm (n. cutaneus antebrachii dorsalis), since the corresponding branches extend from the main trunk of the nerve above, in the middle third of the shoulder. When a nerve is damaged on the forearm, function n. brachioradialis et and. cutanei antebrachii dorsalis, as a rule, persists; prolapse is limited to the defeat of the extensors of the hand and fingers with impaired sensitivity only on the hand. If the lesion is even lower, in the middle third of the forearm, the loss of motor function can be even more limited, while the extension of the hand is preserved, only the extension of the main phalanges of the fingers can suffer.

With damage to the radial nerve, weakness of the extensors of the hand develops, a typical falling or drooping hand arises.

Among the numerous descriptions of samples or tests that determine movement disorders with damage to the radial nerve, one can note:

1. Inability to extend the hand and fingers.
2. Impossibility of abduction thumb.
3. When spreading the palms together with the palms of the hands with straightened fingers, the fingers of the affected hand are not abducted, but the bent ones "slide" along the palm of a healthy, abducted hand.
4. ulnaris (ulnar nerve). The nerve is mixed, composed of fibers of the C8-T1-T2-spinal nerves, passing through first the lower trunk, then the internal bundle of the brachial plexus.

With the defeat of the spinal nerves C8-T1-T2 of the lower trunk and the internal bundle of the brachial plexus, the function of the nerve suffers in the same way in combination with damage to the cutanei brachii and antebrachii mediates (nn. Cutanei brachii et antebrachii mediates) and partial dysfunction of n. mediant, its lower leg (weakening of the flexors of the tenor muscles), which creates a clinical picture of Dejerine-Klumpke's paralysis.

The motor function of the nerve mainly consists in the palmar flexion of the hand, flexion of the V, IV and partly III fingers (mm.lumbricales, flexor digitorum profundus, interossei, flexor digiti V), adduction of the fingers, their dilution (mm.interossei) and adduction of the thumb ( m. adductorpollicis); in addition, in the extension of the middle and terminal phalanges of the fingers (tt. lumbricales. interossei).

With regard to the innervation of the movements of the I and II fingers, the function of the ulnar nerve is conjugated with the function of the median, the first has a predominant relation to the function of the V and IV, the median to the function of the II and III fingers. Sensory fibers innervate the skin of the ulnar edge of the hand, V and partially IV, less often III fingers.

Complete damage to the ulnar nerve causes a weakening of the palmar flexion of the hand (flexion is preserved partly due to m. Flexor carpi radialis et m.palmaris from n. Medianus), the absence of flexion of IV and V, partly of the III fingers, the impossibility of drawing and spreading the fingers, especially V and IV, impossibility of adduction of the thumb.

Superficial sensitivity is usually impaired on the skin of the V and ulnar half of the IV fingers and the corresponding ulnar surface of the hand.

The musculoskeletal feeling is upset in the little finger. Pain with damage to the ulnar nerve is not uncommon, usually radiating to the little finger. Cyanosis, perspiration disorders and a decrease in skin temperature in the area approximately coinciding with the area of \u200b\u200bsensitive disorders are possible. Atrophy of the muscles of the hand in lesions of T. ulnaris are clearly visible, the retraction of the interosseous spaces, especially the first, as well as a sharp flattening of the hypotenor are noticeable.

As a result of the defeat of mm. interossei et lumbricalis, the hand accepts the pitchfork of the "clawed bird paw", with hyperextension of the main phalanges, flexion of the middle and terminal ones is observed, due to which the fingers take a claw-like position. This is especially pronounced in relation to the V and IV fingers. At the same time, the fingers are somewhat divorced, especially the IV and, mainly, the V fingers.

Its first branches n. ulnaris gives off only to the forearm, therefore, its lesion all the way to the elbow joint and the upper part of the forearm gives the same clinical picture.

The defeat in the area of \u200b\u200bthe middle and lower third of the forearm leaves the innervation of mm intact. flexor carpi ulnaris et flexor digitorum profundus, due to which palmar flexion of the hand and flexion of the terminal phalanges of the V and IV fingers do not suffer. But the degree of "clawing" of the hand increases.

To determine movement disorders that occur when the ulnar nerve is damaged, when the hand is squeezed into a fist, there are the following basic tests:

1. When the hand is squeezed into a fist of V and IV, partly III fingers do not bend enough.
2. Flexion of the terminal phalanx of the V finger or "scratching" the little finger on the table with the palm tightly adjacent to it is not feasible.
3. Adduction of fingers is impossible, especially V and IV.
4. Thumb test: the patient stretches a strip of paper, grasping it with both hands between the bent index and straightened thumb; with damage to the ulnar nerve and, consequently, paralysis of m. adductoris pollicis thumb adduction is impossible and the strip of paper is not held by the straightened thumb. In an effort to hold the paper, the patient bends the terminal phalanx of the thumb with m. flexor pollicis, innervated by the median nerve.
5. medianus (median nerve). The mixed nerve is formed from the fibers of the C5, C6, C7, C8 and T1-spinal nerves, which run mainly in the middle and lower trunks of the brachial plexus. Further, the fibers of the median nerve pass in the external and internal bundles. The upper leg extending from the external bundle n. mediani and from the internal bundle, its lower leg merge, forming a loop of the median nerve.

With the defeat of the C7-spinal nerve or the middle trunk of the brachial plexus, the function of the median nerve suffers in part as a result of a weakening of flexion of the hand (m. Flexor carpi radialis), pronation (mm. Pronalores) in combination with damage to the radial nerve.

Almost the same dropout of the function n. mediani occurs when the external bundle of the brachial plexus is damaged, into which the fibers of the upper pedicle of the nerve pass from the middle trunk, but already in combination with damage to the musculocutaneous nerve.

With damage to the C8-T1 spinal nerves, the lower trunk and the internal bundle of the brachial plexus (Dejerine-Klumpke paralysis), they suffer in combination with a lesion n. ulnaris, n. cutanei brachii el anlebrachii medialis fibers n. medianus, which make up its lower leg (weakening of the flexors of the fingers and muscles of the tenor).

The motor function of the nerve mainly consists in pronation, in palmar flexion of the hand due to contraction of m. flexor carpi radialis el m. palmaris longus flexion of the fingers, mainly I, II and III (mm.lumbricales flexor digitorum sublimis el pmfundus, flexorpollicis), extension of the middle and terminal phalanges of II and III fingers.

Sensitive fibers, etc. mediani innervate the skin of the palmar surface of I, II, III and the radial half of the IV fingers, the corresponding part of the palm, as well as the skin of the rear of the terminal phalanges of the named fingers.

When the median nerve is damaged, pronation suffers, palmar flexion of the hand is weakened (preserved only due to m. Flexor carpi ulnaris from n. Ulnaris), flexion of I, II and III fingers and extension of the middle phalanges of II and III fingers are impaired (mm.lumbricalis, inlerossei) ... Superficial sensitivity is impaired on the hand in the zone free of innervation of the ulnar and radial nerves. The joint-muscular feeling is always impaired in the terminal phalanx of the index, and often in the second fingers. Muscle atrophy with damage to the median nerve is most pronounced in the tenor area. The resulting flattening of the palm and bringing the thumb close and in one plane to the index finger create a peculiar position of the hand, which is called "monkey".

Pain with damage to the median nerve, especially partial, is quite intense and often takes on the character of causalgic. In the latter case, the position of the hand can take on a bizarre character. Also common and characteristic for lesions of the median nerve and vasomotor-secretory-trophic disorders: the skin, especially the I, II and III fingers becomes cyanotic or pale; become "dull", brittle and streaked nails; there is skin atrophy, thinning of the fingers (especially II and III), sweating disorders, hyperkeratosis, hypertrichosis, ulceration, etc. These disorders, like pain, are more pronounced with partial, and not with complete damage n. medianus.

Its first branches n. medianus, as well as n. ulnaris, gives only to the forearm, therefore, the clinical picture with a high lesion along the entire length from the armpit to upper divisions the forearms are the same.

If n. mediani in the middle third of the forearm, in which branches extending to mm are preserved. pronator leres, flexor carpi radialis, palmaris longus flexor sublimis, the functions of pronation, palmar flexion of the hand and flexion of the middle phalanges are not affected. With lower lesions of the nerve, the flexion function of the terminal phalanges of the I, II and III fingers may also be preserved.

The main tests for the determination of movement disorders that occur with damage to the median nerve are as follows:

1. When clenching the hand and fist I, II and partly III fingers do not bend
2. Flexion of the terminal phalanges of the thumb and forefinger is impossible, as is the scratching of the index finger on the table with the hand tightly attached to it.
3. With a thumb test, the patient cannot hold a strip of paper with a bent thumb and will hold it by bringing it with a straightened thumb (mm. Adductor policis from preserved n. Ulnaris).
4. cutaneus brachii medialis (cutaneous internal nerve of the shoulder). The sensory nerve, whose fibers arise from C8, T1, partly from the T2-spinal nerves and pass through first the lower trunk, then the internal bundle of the brachial plexus and innervate the skin of the inner surface of the shoulder. With its defeat, there are disturbances in sensitivity and pain in the shoulder area.
5. cntaneus antibrachii medialis (cutaneous internal nerve of the forearm). Sensory nerve. It innervates the skin of the inner surface of the forearm. Formed from C8-T2 spinal nerves.

When the nerve is damaged, sensory disturbances occur, possibly pain in the forearm area.

Isolated lesions of these nerves are rare. Their defeat is often included in the clinical picture of damage to the lower trunk or internal bundles of the brachial plexus or is observed in combination with lesions of other nerves of the limb.

The main problem that needs to be solved in order to select the appropriate treatment is the most accurate and early determination of the level of damage.

Indications for neurosurgical operations are clinical signs of severe upper and total paralysis, Horner's syndrome, relaxation of the diaphragm, lack of restoration of motor and sensory functions of the upper limb in infants. The most optimal age of patients for neurosurgical operations is the first year of life.
For operations on the brachial plexus, the transverse supraclavicular approach and its modifications, as well as the transclavian approach, are used.
The methods of choosing neurosurgical operations are external and internal neurolysis, plastic and suture of nerves, neurotization

Comparison of groups of children treated only conservatively and with the use of neurosurgery showed that the latter significantly improves outcomes.