Brachial Plexus Neuritis: Symptoms, Causes, and Treatment Options

Brachial plexus neuritis is a term used to describe a neurological inflammatory syndrome now known to be caused by cervical spondylosis.

The brachial plexus is a complex neural plexus, highly intricate in both its structure and function, and is also a plexus prone to disorders. Therefore, it holds great clinical significance.

The primary causes are focal infection or inflammation of adjacent tissues; they are also observed in infectious diseases such as influenza and typhus. In most cases, the condition results from compression due to pathological changes in neighboring structures, including cervical spondylosis with nerve root compression, cervical disc herniation, cervical tuberculosis or tumor, fracture, dislocation, cervical spinal cord tumor, arachnoiditis, etc. Conditions that compress the nerve trunk include thoracic outlet syndrome, cervical rib, neck tumor, axillary lymphadenopathy (e.g., metastatic carcinoma), clavicle fracture, etc. It may also be caused by brachial plexopathy or trauma, with cervical spondylosis being the most common among them.

【Diagnostic Criteria】

It is more common in adults, occurring after influenza when the neck or arm is exposed to cold during sleep.

Onset occurs when the body’s constitution is compromised. The condition presents acutely or subacutely, with pain first appearing in the neck, shoulder, and supraclavicular region, rapidly spreading to the posterior shoulder, and within a few days extending to the arm, forearm, and hand. Initially, the pain is intermittent but soon becomes persistent, affecting the entire upper limb. The patient adopts a posture with the elbow flexed and avoids movement to alleviate pain, though occasionally they may adjust the position of the upper limb to find a more comfortable posture. Sleeping on the affected side is not possible. There is significant tenderness over the brachial plexus trunk (supraclavicular, infraclavicular, or axillary regions). Traction of the brachial plexus, such as abduction or elevation of the upper limb, provokes pain. Muscle strength in the upper limb is reduced. Tendon reflexes are initially hyperactive but soon diminish or disappear. Muscle atrophy and cutaneous sensory disturbances are often not prominent; light touch or needling of the hand and fingers may produce a numb sensation. In severe cases, finger swelling and thinning of the skin with a smooth appearance may occur. If appropriate treatment is given at the onset, the pain usually resolves within a short period.

[Treatment]

1. Acupoints and Needling Techniques

1. **LI17 (Tianding), affected side**: Located in the supraclavicular fossa, 1 _cun_ below LI18 (Futu), at the posterior border of the sternocleidomastoid muscle. A No. 30 filiform needle, 1.5 _cun_ in length, is used. After routine disinfection of the local area, insert the needle approximately 1.2 _cun_ toward the spinal column. Needling sensation: local distension and pain, or radiation to the upper arm and hand.

2. **LI15 (Jianyu)** (affected side): Located in the upper central part of the deltoid muscle, between the acromion and the greater tubercle of the humerus. When the arm is abducted to a horizontal position, two depressions appear; the point is in the anterior depression. Insert a 30-gauge, 2-cun filiform needle. Needling sensation: local distension and pain, or a radiating sensation toward the elbow.

3. LU2 (Yunmen) on the affected side: located 6 cun lateral to the Conception Vessel (CV), in the depression on the lower border of the clavicle. Use a 30-gauge, 2.5 cun filiform needle. After routine local disinfection, insert perpendicularly toward the contralateral SI9 (Jianzhen) to a depth of approximately 2.3 cun. Needling sensation: distending pain in the shoulder or radiation to the hand.

4. **LI14 (Binao) on the affected side**: Located on the line connecting LI11 (Quchi) and LI15 (Jianyu), 7 cun above LI11, at the lower border of the deltoid muscle. Use a 30-gauge, 2-cun filiform needle. After routine local disinfection, insert perpendicularly toward the medial border of the humerus to a depth of approximately 1.8 cun. Needling sensation: radiates to the radial side of the upper elbow.

5. LI11 (Quchi) (affected side): Located on the elbow, with the elbow flexed and the hand in a “palms-up” (supplication) position, in the depression at the radial end of the cubital crease. A 30-gauge, 2-cun filiform needle is used. After routine local disinfection, insert perpendicularly toward HT3 (Shaohai). Sensation: local distension and pain.

6. **PC6 (Neiguan)** (affected side): Located 2 cun proximal to the palmar wrist crease, between the tendons of the palmaris longus and flexor carpi radialis muscles. A 30-gauge, 1.5 cun filiform needle is used. After routine local disinfection, insert perpendicularly toward TE5 (Waiguan) to a depth of approximately 1.3 cun. Sensation: Local distension and pain, or radiation toward the dorsum of the hand and the middle finger.

7. **LI4 (Hegu) (affected side)**: Located on the dorsum of the hand, between the first and second metacarpal bones, at the midpoint near the radial side of the second metacarpal bone. Use a 30-gauge, 2-cun filiform needle. Perform routine local disinfection. Insert approximately 1.8 cun toward SI3 (Houxi). Needle sensation: local distension and pain.

2. Methods

The patient is seated. The aforementioned acupoints are needled according to the standard method and the needles are retained for 40 minutes, with one manual needle twirling in the middle of the retention. Upon needle removal, cupping is applied for approximately 1 minute. Treatment is administered once daily, with 6 sessions constituting one course of treatment. A 3-day rest period is observed before commencing the next course.

【Commentary】

The clinical etiology of brachial plexus neuritis is complex, with severe pain upon onset. The aforementioned therapy is generally effective for most cases. However, for more severe patients—such as those with nerve root inflammation caused by cervical disc herniation—although initial treatment yields considerable benefit, the resolution of hand and upper arm numbness requires a longer period. If the herniation is severe, traction and other methods should be combined to achieve satisfactory results. When accompanied by other complications, such as pulmonary or cardiac conditions, reference to relevant materials and combined treatment can also yield satisfactory outcomes.

Etiology and Pathophysiology of Brachial Plexus Neuritis

Brachial plexus neuritis causes are multifactorial, with contemporary clinical evidence strongly implicating cervical spondylosis as a primary etiological mechanism. The brachial plexus, a highly intricate neural network arising from the C5 to T1 spinal nerves, is anatomically vulnerable to compressive and inflammatory insults. Degenerative changes in the cervical spine, such as osteophyte formation and intervertebral disc pathology, can lead to chronic irritation or focal inflammation of adjacent neural tissues. Additionally, systemic infectious diseases—including influenza, typhus, and other viral or bacterial pathogens—may precipitate an immune-mediated inflammatory response targeting the plexus. Focal infections in perineural structures, such as those arising from dental, tonsillar, or sinusal sources, further contribute to the neuritic process. The resultant inflammation disrupts axonal conduction and induces demyelination, manifesting as a painful and functionally debilitating condition. Understanding these underlying causes is essential for accurate diagnosis, as the condition may be misattributed to primary shoulder pathology. The intricate anatomical complexity of the brachial plexus renders it particularly susceptible to such inflammatory and compressive disorders, underscoring the clinical significance of recognizing cervical spondylosis as a central, yet often overlooked, causative factor.

Clinical Manifestations: Pain and Neurological Deficits

Brachial plexus neuritis symptoms typically present with an acute onset of severe, unilateral pain localized to the shoulder and upper arm. This initial pain phase is often described as deep, aching, and relentless, and it may radiate along the distribution of the affected nerve roots. A hallmark of the condition is brachial plexus neuritis shoulder pain, which can be so intense that it limits range of motion and mimics other common shoulder disorders, such as rotator cuff pathology or glenohumeral arthritis. Following the painful prodrome—usually within days to a few weeks—patients develop motor weakness, sensory disturbances (including paresthesias or hypoesthesia), and, in some cases, muscle atrophy affecting the deltoid, supraspinatus, infraspinatus, or biceps brachii. The pain may subside as neurological deficits emerge, a pattern that is diagnostically important. Bilateral involvement occurs in a minority of cases, and autonomic changes may also be observed. The clinical presentation is highly variable, reflecting the selective and patchy nature of the inflammatory process within the plexus. Recognizing these characteristic symptom patterns is critical for differentiating brachial plexus neuritis from other cervicobrachial pain syndromes, thereby guiding appropriate management strategies.

Therapeutic Strategies and Medical Management

Brachial plexus neuritis treatment is primarily conservative and symptom-directed, with a focus on pain control, inflammation reduction, and functional preservation. During the acute painful phase, high-dose nonsteroidal anti-inflammatory drugs (NSAIDs) or short courses of oral corticosteroids are often employed to mitigate neural inflammation and provide analgesia. For refractory pain, neuropathic agents such as gabapentin or pregabalin may be added, and in severe cases, opioid analgesics or interventional procedures like nerve blocks are considered. Once the acute pain subsides, physical therapy becomes the cornerstone of rehabilitation, emphasizing gentle range-of-motion exercises to prevent joint contractures, followed by progressive strengthening of affected muscle groups. Occupational therapy assists with ergonomic modifications and adaptive techniques for daily activities. In cases where cervical spondylosis is identified as the underlying cause, treatment must also address the spinal pathology—through cervical traction, postural correction, or, in selected instances, surgical decompression if significant nerve root compression persists. Early and individualized intervention is essential to minimize long-term disability, and treatment plans should be regularly reassessed based on clinical response and evolving neurological findings.

Prognosis and the Path to Functional Recovery

Brachial plexus neuritis recovery time varies considerably among patients, with the majority experiencing gradual improvement over months to several years. The recovery trajectory is influenced by the severity of the initial inflammatory insult, the degree of axonal loss, and the timeliness of therapeutic intervention. In most cases, the painful phase resolves within two to four weeks, while motor recovery may extend from six months to two years or longer. Complete functional restoration is anticipated in approximately 70–80% of patients, although residual weakness, sensory sequelae, or mild muscle atrophy may persist in a subset of individuals. Factors associated with a favorable prognosis include younger age, absence of significant muscle atrophy at presentation, and early initiation of structured rehabilitation. Conversely, severe axonal degeneration or delayed treatment may prolong recovery and increase the likelihood of permanent deficits. Serial electrodiagnostic studies, including electromyography and nerve conduction studies, can provide objective prognostic information by quantifying the extent of denervation and reinnervation. During the recovery period, consistent adherence to physical therapy and regular clinical follow-up are paramount. Patients should