Mononeuropathy and Plexus Neuropathy

Introduction to mononeuropathy and plexus neuropathy Peripheral spinal neuropathy refers to the structural and dysfunction of motor neurons in the spinal cord and brainstem, primary sensory neurons, axons of surrounding autonomic neurons, and/or Schwann cells and myelin. basic knowledge The proportion of sickness: 0.002%-0.003% Susceptible people: no specific people Mode of infection: non-infectious complication:

Single neuropathy and the cause of plexus neuropathy

(1) Causes of the disease

According to the medical history and various laboratory tests, various causes of neuropathy around the spinal cord can be identified.

1. The cause of brachial plexus is complex, mainly including the following aspects:

(1) Trauma: The upper limb is exposed to violence during a car accident and mechanical wounding. The impact is the most common cause of traumatic brachial plexus.

(2) Thoracic outlet syndrome.

(3) Physical damage: such as electric shock and radioactive damage.

(4) acute brachial plexus neuritis: also known as neuropathic muscle atrophy, often after the flu or after the use of drugs such as penicillin, acute or subacute onset, may be related to autoimmunity.

(5) genetic factors: such as familial recurrent brachial plexus neuropathy or genetic familial brachial plexus neuropathy, some patients with neurobiopsy showed myelin hypertrophy, a sausage-like change, similar to hereditary stress-susceptible peripheral neuropathy.

(6) Tumor: The most common is brachial plexus schwannomas, followed by brachial plexus fibroids.

(7) Perinatal brachial plexus neuropathy: During the delivery process, when the shoulder of the fetus is difficult to deliver, the fetal head is pulled hard, which is easy to cause brachial plexus injury. It occurs mostly in large infants larger than 4000g, but a considerable part of the body weight is less than Brachial plexus injury can also occur in 4000 g, and newborns with difficulty in delivering shoulders, suggesting that there may be other causes other than birth trauma.

(8) Chronic brachial plexus neuropathy: refers to a group of slowly progressive idiopathic brachial plexus neuropathy with unknown causes.

2. The cause of intercostal neuralgia is mainly related to the involvement of adjacent tissues and organs in the intercostal nerve. Common causes are pleurisy, pneumonia, aortic aneurysm; trauma of thoracic and ribs, tumor, deformity; cavity of the thoracic spinal cord, inflammation And tumors, etc., varicella or herpes zoster infection and post-infection intercostal neuralgia are common in the elderly, HIV patients, malignant tumors and chemotherapy patients.

3. The etiology of lumbosacral plexus neuropathy is complex, mainly in the following aspects:

(1) Diabetic proximal muscle atrophy: It is thought to be caused by bilateral lumbosacral plexus involvement, and the immune mechanism plays an important role in nerve injury.

(2) Trauma and hemorrhagic diseases: pelvic fractures caused by trauma, puncture or pelvic hematoma, hip dislocation, fractures, etc. can cause lumbosacral plexus injury, blood diseases or patients with anticoagulant therapy can be waist Large muscle or iliopsoas hematoma, directly invading the lumbosacral plexus.

(3) iatrogenic: abdominal and pelvic surgery such as hysterectomy, kidney transplantation, prostate and bladder surgery, etc. due to the use of self-limiting stretcher, its sharp leaves are easy to oppress the lumbosacral plexus, causing injury, kidney transplantation Because the donor renal artery is consistent with the inferior luminal artery of the recipient, it is easy to cause arterial stealing, which causes lumbosacral plexus ischemia. When the hip arthroplasty is performed, the adhesive can be squeezed out of the pelvis to compress the nerve plexus.

(4) Aortic and pelvic artery malformations: abnormal blood vessel rupture and hemorrhage form a pelvic hematoma compression lumbosacral plexus.

(5) Production process: maternal primipara or large fetus due to long labor, long-term stone removal position makes the hip joint excessive abduction easily cause lumbosacral plexus injury.

(6) Tumor: Tumor lumbosacral plexus disease is more common, and the diagnosis is more difficult. CT, MRI and lumbar puncture often have no abnormal findings. Prostate, rectum, bladder and kidney tumors can invade the lumbosacral plexus and its surroundings through local diffusion. Lymph nodes, giant fibroids in the posterior uterus, and endometriosis can directly compress the lumbosacral plexus, and aneurysms formed by aortic atherosclerosis can also involve the plexus.

(7) Infection: Psoas major tuberculous abscess, lumbar osteomyelitis, appendicitis, inflammation can invade the lumbosacral plexus through the diaphragmatic fascia, sometimes varicella or herpes zoster infection can also cause lumbosacral neuralgia and corresponding skin Herpes, systemic vasculitis can involve lumbosacral plexus causing vasculitis peripheral neuropathy.

(8) Radioactivity: Radiation of pelvic tumors can cause radiation lumbosacral neuropathy.

(9) Idiopathic: Corresponding to the acute brachial plexus neuritis of the upper extremity, the lower extremity may have idiopathic lumbosacral plexus neuritis, and the pathological mechanisms of both may be related to autoimmune abnormalities.

4. Sciatica is divided into root and dry sciatica according to the lesion.

(1) more common roots, mainly intraspinal and spinal lesions, lumbar intervertebral disc prolapse most common, other such as lumbar hypertrophic spondylitis, lumbosacral dural radiculitis, spinal tuberculosis, spinal stenosis, vascular malformation, waist A segment of the spinal canal or arachnoiditis.

(2) dryness is mostly lumbosacral plexus and nerve trunk adjacent lesions, such as ankle arthritis, tuberculosis or subluxation, as well as psoas abscess, pelvic tumor, uterine annexitis, pregnancy uterus compression, improper gluteal injection, buttocks Trauma and infection, etc.

(two) pathogenesis

Lower motor neurons in the peripheral nerve distribution of the lesion, primary sensory neurons, axons of surrounding autonomic neurons, and/or structural and dysfunction of Schwann cells and myelin, leading to clinical exercise, sensory and autonomic function Damage symptoms and signs.

For example, the pathogenesis of intercostal neuralgia after infection may be related to the reactivation of varicella-zoster virus latent in the posterior root ganglia in the absence of low immunity. Pathological examination reveals that the posterior root myelin sheath and axon are swollen. , disintegration, followed by macrophage infiltration and fibrous tissue hyperplasia, the posterior root into the spinal cord can be seen in the segmental unilateral posterior polio, after several months and years of infection, visible post-root hardening, which may be The pathological basis of neuralgia after varicella-zoster virus infection. In recent years, electron microscopy and immunofluorescence antibody studies have found that there are viruses in Schwann cells, nerve bundle membranes and neuroendocrine cells.

Single neuropathy and plexus neuropathy prevention

It is mainly to prevent the damage of peripheral nerves in various primary diseases. In the treatment, neurotrophic metabolism drugs such as B vitamins, vitamin E, citicoline, ATP, coenzyme A and nerve growth factor should be selected as soon as possible. Or can promote the improvement of nerve function.

Single neuropathy and plexus neuropathy complications Complication

Symptoms and signs of clinical movement, sensory and autonomic dysfunction caused by axons and/or Schwann cells and myelin damage in the lesioned neurons, the extent of which is related to the primary cause, peripheral nerve damage symptoms and primary The symptoms of the disease exist at the same time.

In severe cases, there may be complete sputum, sensory disturbance, autonomic dysfunction and related symptoms and signs of the primary disease. For example, when the lumbosacral plexus is damaged by trauma, there may be urination, defecation, and lower extremity edema. Rheumatoid, vasculitic or diabetic plexus, there must be other manifestations of the primary disease.

Symptoms of mononeuropathy and plexus neuropathy Common symptoms Muscular atrophy, sensory disturbance, radiation pain, obturator nerve damage, pre-spinal mutation, local partial pain, dull pain, reflex, disappearance, shoulder muscle, upper limb and... femoral nerve damage

1. Brachial plexus neuropathy caused by various causes of brachial plexus injury, collectively referred to as brachial plexus neuropathy, is one of the most common plexus diseases. The main clinical manifestations of brachial plexus neuropathy include the muscles of the shoulder muscles, the upper limbs and the muscles of the chest and back. Inability and muscle atrophy, the affected skin area of the brachial plexus branches is numb, pain and sensation diminished.

According to the location of the affected area and the degree of damage, there may be different forms of symptom combinations in the clinic. The muscle innervation and function of the brachial plexus branches are shown in Table 1.

The upper brachial plexus (dry on the brachial plexus) is also known as Duchenne-Erb palsy. Its clinical features are the shoulder muscles and the proximal muscles of the upper limbs, which are manifested as the subscapularis muscle, the great round muscle, the supraspinatus muscle, the infraspinatus muscle, the deltoid muscle. , pectoralis major muscle clavicle, radial flexor digitorum, pronated round muscle, diaphragm and supinator muscle weakness, atrophy, shoulder abduction, lifting, elbow flexion and wrist flexion and extension can not, sensory disturbance is not obvious, Sometimes the upper limbs and the lateral side of the hand have a feeling of loss.

The lower brachial plexus (dry under the brachial plexus) is also known as Klumpke-Dejerine palsy. Its clinical features are the motor function of the hand, the ulnar wrist flexor, the sacral muscle, the large and small muscle muscles and all the flexor muscle paralysis. The hand muscles are atrophied, forming a claw-shaped hand, the flexion of the fingers and wrists is not possible, and the activities of the extensors and shoulders and elbow joints are not affected.

The main injury in the brachial plexus is rare. The main symptoms are weakness of the extensor muscles of the upper limbs. The clinical features of the total brachial plexus lesions are shoulder, elbow, wrist, hand joint movement, muscle atrophy, and upper extremity tendon reflexes, except the intercostal arms. The inner part of the inner arm of the innervation of the inner part of the arm feels to remain, and the rest of the upper limb feels completely lost.

2. Intercostal neuralgia refers to the pain in the intercostal nerve innervation. It is often located in one or several intercostal spaces. It is often persistent burning pain. Breathing, coughing and sneezing can induce pain, and the examination can sometimes be seen. The intercostal area is hyperalgesia.

The skin reaction of herpes zoster infection often occurs several days after intercostal neuralgia, first manifested as skin erythema, followed by small blisters, followed by suppuration and formation of small ulcers. Head and Campbell (1900) autopsy pathology revealed that the skin After 1 to 2 weeks of damage, the root ganglion cells were severely damaged, and the posterior root nerve myelin sheath and axons were swollen and disintegrated, followed by macrophage infiltration and fibrous tissue hyperplasia. The posterior roots were found in the spinal cord. Lateral keratitis, after several months and years of infection, can be seen after the root knot hardening, which may be the pathological basis of neuralgia after varicella zoster virus infection.

In recent years, the application of electron microscopy and immunofluorescence antibody studies have found that there are viruses in Schwann cells, nerve bundle membranes and neuroendocrine cells.

3. The lumbosacral plexus lumbosacral lumbosacral nerve roots, plexus and main branches (neural trunk) have their own clinical features when they are injured. The muscle innervation and function of different spinal cord nerve branches are shown in Table 2.

When the lumbosacral nerve root is damaged, there may be radiation pain, bending, sneezing, coughing and neck flexion can make the pain worse, straight leg elevation test is positive, lumbar motion is limited, the front of the spine is abrupt, local pain, vertical Spinal tendon, simple nerve root damage generally does not affect autonomic nerve function, multiple nerve root damage and nerve plexus damage are difficult to identify.

When the plexus is damaged, the straight leg elevation test is more negative. When the intraspinal pressure increases, the pain does not increase. The exercise and sensory involvement often exceed the dominating area of one nerve root. When the upper lumbar plexus is damaged, the hip flexion and abduction and knee extension are weak. The sensory disturbance is distributed in the front of the thigh and the lower leg. When the lower plexus is damaged, the muscles of the posterior femoral muscle are weakened. The muscles of the calf and the foot are weak. The sensation of the sacral nerve segments is rare. All the lumbosacral plexus lesions are rare, and the whole lower limb muscles are expressed., weakness and atrophy, sputum reflex disappears, the feeling from the tip of the toe to the anus is reduced or absent, autonomic nerve involvement is characterized by dry skin, fever, often calf edema, rectal examination can touch tender points, lump or swelling The prostate.

Nerve stem damage is mainly manifested by the involvement of motor-related motor and sensory functions.

When the femoral nerve is damaged, the iliopsoas muscles, the sartorius muscles and the quadriceps muscles, which are innervated by the motor nerve fibers, are weak, showing knee extension and hip weakness, and the thigh abduction is not tired (dominated by obturator nerves). Distinguishing from the injury of the lumbar 3 spinal nerve roots, there is a sensory disturbance in the sensory distribution of the femoral nerve in the anterior medial thigh and calf.

Obturator nerve damage manifests as external thigh rotation, difficulty in flexion, and the adductor muscle group is co-administered with the sciatic nerve, thus showing incomplete paralysis.

The lateral femoral nerve nerve damage is mainly seen in middle-aged men. Excessive obesity and unfit clothing are the predisposing factors. The clinical manifestation is that after standing for a long time and walking, there are skin numbness and tingling in the outer 2/3 area of the lateral thigh. Decreased and feeling allergic.

The sciatic nerve damage is mainly sciatica, which is a pain syndrome along the sciatic nerve pathway and its distribution area. The sciatic nerve is composed of the lumbar 4~3 nerve roots. It is the longest and thickest nerve in the whole body, and the hip is distributed throughout the lower limbs. According to the cause of the disease, it is divided into primary and secondary sciatica. The primary is also called sciatic neuritis. The cause is unknown. It can be caused by infection of the teeth, paranasal sinus and tonsil. Interstitial neuritis is caused by blood flow invading the peripheral nerve. Secondary is caused by lesions or organ compression on the sciatic nerve pathway.

Acute lumbar disc herniation usually leads to pain in the distribution of nerve roots (lumbar 5 or 1) in the back and legs, often accompanied by numbness and paresthesia; motor function defects depend on the affected nerve roots, and the lumbar 5 spinal nerve roots cause weakness in the dorsiflexion of the feet and toes.1 spinal nerve root involvement produces foot flexor weakness and sacral reflexes, which may have limited spinal motion, limited back tenderness, and paraspinal tendon and Lasegue sign. Central lumbar disc herniation leads to bilateral symptoms, signs and sphincters. Affected.

4. Sciatica is divided into root and dry sciatica according to the lesion.

(1) more common roots, mainly intraspinal and spinal lesions, lumbar intervertebral disc prolapse most common, other such as lumbar hypertrophic spondylitis, lumbosacral dural radiculitis, spinal tuberculosis, spinal stenosis, vascular malformation, waist A segment of the spinal canal or arachnoiditis.

(2) dryness is mostly lumbosacral plexus and nerve trunk adjacent lesions, such as ankle arthritis, tuberculosis or subluxation, as well as psoas abscess, pelvic tumor, uterine annexitis, pregnancy uterus compression, improper gluteal injection, buttocks Trauma and infection, etc.

Single neuropathy and plexus neuropathy

1. Blood tests include blood glucose, liver function, kidney function, erythrocyte sedimentation rate, serological routine examination of hepatitis B and hepatitis C; serum thyroxine and growth hormone levels; serum vitamin B1, B6, B12 and vitamin E concentrations; rheumatism series, ANCA , immunoglobulin electrophoresis, cryoglobulin, M protein, anti-GM-1 antibody, anti-GD1a antibody, anti-MAG antibody, tumor-associated antibody (anti-Hu, Yo, Ri antibody) and other serological tests related to autoimmunity; Serum antibody detection of herpes zoster virus, cytomegalovirus, HIV-1 and Borrelia Burgdorferi; detection of serum heavy metals (lead, mercury, arsenic, antimony, etc.).

2. Urine examination includes urine routine, pre-week protein, urinary porphyrin and heavy metal excretion in urine.

3. Cerebrospinal fluid should be checked against anti-GM-1, GD1b antibodies in addition to routine cerebrospinal fluid.

4. Suspected paraneoplastic peripheral neuropathy, paraprotein peripheral neuropathy or POEMS syndrome should be performed on chest and bone X-ray and bone marrow cytology.

5. Analysis of genetic defects Some hereditary peripheral neuropathy can be diagnosed by genetic defect detection, such as TIR mutation detection for the diagnosis of amyloid peripheral neuropathy, PMP22 gene deletion for the diagnosis of hereditary stress susceptibility peripheral neuropathy, PMP22 repeat, Po Mutation and ligandin-32 gene analysis were used for the diagnosis of CMT1A, 1B and X-linked genotype CMT, respectively.

6. Muscle and neurophysiological examinations are of great significance in identifying neurogenic and myogenic damage, the location of peripheral nerve damage, and the distinction between axonal degeneration and demyelination.

7. Peripheral nerve biopsy is an important laboratory test for differential diagnosis of peripheral neuropathy.

Diagnosis and differentiation of single neuropathy and plexus neuropathy

Diagnostic criteria

Sciatica is common in young adults, characterized by radiation pain along the sciatic nerve path, mostly unilateral, from the lower back or buttocks to the posterior part of the thigh, the posterior lateral part of the calf, and the lateral side of the foot, showing persistent dull pain or burning pain. Paroxysmal aggravation, often aggravated at night, walking, activity or traction can induce or aggravate, the patient takes a pain-reducing posture, the affected limb is slightly flexed and the lateral side is placed in the lateral position, and the knee joint is bent when the patient is standing upright. The buttocks are first focused, and the spine is convex toward the affected side when standing.

1. Brachial plexus neuropathy In the case of non-same plane cutting injury, any two or more brachial plexus branches should be considered for the possibility of brachial plexus.

Domestic Gu Yudong emphasized the importance of the five major nerve involvement of the upper extremity in the diagnosis of brachial plexus. One of the following conditions should be considered: the presence of brachial plexus injury: 1 nerve, musculocutaneous nerve, median nerve, ulnar nerve and phrenic nerve Joint damage of any two nerves, 2 median nerves, ulnar nerve and sacral nerve combined with shoulder or elbow joint dysfunction, 3 median nerve, ulnar nerve and phrenic nerve combined with medial forearm cutaneous nerve injury.

2. Intercostal neuralgia is not difficult to diagnose based on its pain distribution area and characteristics.

3. The diagnosis of lumbosacral nerve roots, plexus and nerve trunk damage mainly depends on clinical manifestations. Because they are spatially a continuation relationship, sometimes it is difficult to identify, such as the lower part of the sac, the sciatic nerve and the common peroneal nerve can cause damage. The same motor dysfunction, neurophysiological examination may be helpful for localization diagnosis, lumbosacral vertebrae and pelvic CT, MRI can provide a basis for finding the cause.

4. Sciatica According to the distribution of pain, radiation path and tenderness, the cause of pain aggravation and relief, Lasegue sign, sputum reflex, weakened calf and lateral sensation of the foot, it is not difficult to diagnose, we must pay attention to distinguish between root and dryness, waist Symptoms and signs of disc herniation can occur suddenly or insidiously, or after trauma, lumbar X-ray film or MRI, pelvic and rectal examination can help to exclude tumors and other lesions.

Differential diagnosis

1. Lumbosacral nerve roots, nerve plexus and nerve trunk damage must be differentiated from lumbar muscle strain, hip fibrosis, hip arthritis, etc., the latter can cause pain in the lower back, buttocks and lower extremities, but no radiation pain, no muscle strength Decreased, sputum reflexes and sensory disturbances.

2. Etiology identification should pay attention to spinal horsetail tumor, degenerative spondylitis (proliferative spondylitis), spinal tuberculosis, tumor, crack and syringomyelia, biceps tenosynovitis, piriformis syndrome, etc., spine X-ray, CT, or MRI examination can help diagnose.

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