bubble_chart Overview

The brachial plexus is formed by the anterior branches of the spinal nerves from C5 to T1, responsible for the sensation and movement of the upper limb. Brachial neuralgia refers to pain in the innervated area caused by any damage to the brachial plexus.

bubble_chart Etiology

disease cause and pathogenesis of disease

1. A minority of patients have primary cases with unknown disease cause. Since it often occurs after influenza or upper respiratory infections, it may be related to infection or allergic reactions, hence the term brachial plexus neuritis.
2. Most patients experience compression of nerve roots or nerve trunks due to adjacent tissue lesions. Compression of nerve roots is commonly seen in cervical spondylosis, cervical herniation of intervertebral disc, cervical subcutaneous nodules, tumors, fractures, etc. Compression of nerve trunks is often caused by cervical ribs, thoracic outlet syndrome, neck tumors, etc. Among the disease causes of brachial plexus neuralgia, cervical spondylosis is the most common.

Cervical spondylosis is a clinical syndrome caused by degenerative changes in intervertebral discs and osteophyte formation in vertebral bodies. With age, the intervertebral discs degenerate, the nucleus pulposus protrudes, and becomes embedded between the anterior or posterior longitudinal ligaments and the bone membrane, gradually becoming fibrotic and calcified, forming osteophytes. The proliferation of osteophytes is also related to the greater degree of weight-bearing and movement in cervical vertebrae C4, C5, and C6, increasing the likelihood of injury. Prolonged hyperextension or hyperflexion of the neck, neck muscle tension, etc., can all induce cervical spondylosis, narrowing and deforming the intervertebral foramina, compressing nerve roots, or even the spinal cord, leading to symptoms.

bubble_chart Clinical Manifestations

There are many disease causes of brachial plexus neuralgia, but the basic characteristics are similar. This condition is more common in adults and presents with acute or subacute onset. The pain often starts in one shoulder or neck and spreads to the entire ipsilateral upper limb within a few days. The pain is persistent or paroxysmal, with sensations of stabbing, burning, electric shock, or soreness and distension. The location corresponds to the distribution of the nerve root segments, either predominantly in the shoulder and lateral upper limb or in the supraclavicular and infraclavicular fossae and the medial upper limb. The pain worsens with upper limb movement or certain postures and is more severe at night. Flexing the elbow and reducing activity can alleviate the pain.

Examination may reveal reduced pain sensation in the brachial plexus region, weakened muscle strength, and localized muscle atrophy, especially in the shoulder girdle, with rare fasciculations. In the late stage [third stage], tendon reflexes may weaken or disappear, and some patients may exhibit autonomic nervous system symptoms.

bubble_chart Diagnosis

1. Acute or subacute onset of unilateral upper limb pain, which is position-related.
2. Examination reveals muscle weakness, sensory impairment, and diminished or absent reflexes.
3. In cases caused by cervical spondylosis, cervical spine X-rays show osteophyte formation and narrowed intervertebral foramina.

bubble_chart Treatment Measures

The principle is to remove the disease cause as much as possible, alleviate or eliminate pain.

1. Disease cause treatment: For brachial plexus neuritis, prednisone 10mg can be taken three times daily for two weeks, combined with vitamin B1, B12, etc. For cervical spondylosis, a cervical brace or traction can be used; if conservative treatment is ineffective, surgical treatment may be considered. Avoid excessive extension or flexion of the neck.
2. General treatment
   1. Reduce activity of the affected limb and use a sling to maintain the elbow in a flexed position against the chest.
   2. Oral analgesics and muscle relaxants may be administered. For example, indomethacin 25mg three times daily; fenarol 0.2, three to four times daily; estazolam 1mg three times daily.
   3. Local block: Inject 0.5–1ml of 2% procaine and prednisolone at the pain point. Generally, this is done once every five days, for a total of 3–5 sessions.
   4. Physical therapy and acupuncture can also be effective.

bubble_chart Prognosis

Generally, recovery takes 2 to 4 weeks, but in some cases, it may last several months or even result in muscle atrophy.

bubble_chart Differentiation

1. Cervical subcutaneous nodes or metastatic tumors, in addition to causing pain, may show cervical bone destruction on X-ray films or primary lesions elsewhere in the body.
2. Bone, joint, and soft tissue lesions in the shoulder region present with persistent dull pain, obvious tenderness, and bone or joint changes on X-ray films, lacking neurological abnormalities, making them easy to differentiate.