What are the symptoms and treatment options for brachial plexus injury?

Symptoms and Treatment of Brachial Plexus Injury

Clinical Presentation

Brachial plexus injuries present with a characteristic pattern of pain, sensory changes, and motor weakness in the affected upper extremity, with symptoms varying based on the location and severity of injury. 1

The primary symptoms include:

• Pain: Neuropathic pain in the shoulder and arm with burning or electric sensations occurring in multiple peripheral nerve distributions
• Sensory changes: Dysesthesia, numbness, and sensory loss in affected nerve territories
• Motor deficits: Weakness or paralysis of affected muscles with flaccid loss of tendon reflexes
• Autonomic changes: Temperature and color changes in the limb due to autonomic nervous system damage

Symptom patterns based on injury location:

• Upper trunk injuries (C5-C6): Shoulder and elbow dysfunction
• Lower trunk injuries (C8-T1): Hand and wrist dysfunction
• Complete plexus injury: Total limb paralysis 1

Causes and Risk Factors

Brachial plexus injuries can result from:

• Trauma: Most common in young men after high-energy injuries or elderly women after simple falls 2
• Neoplastic processes: Primary tumors (schwannomas, neurofibromas) or metastatic disease (lung, breast cancer)
• Radiation therapy: Radiation-induced brachial plexopathy
• Inflammatory/immune-mediated causes: Parsonage-Turner syndrome, chronic inflammatory demyelinating polyradiculoneuropathy 1

Risk factors for poor outcomes include:

• Advanced age
• Higher energy trauma
• Delayed reduction of shoulder dislocation 2

Diagnosis

The diagnostic approach includes:

1. Clinical examination: Assess motor function, sensory changes, and reflex responses in the affected limb

2. Imaging studies:

   • MRI of the brachial plexus: Gold standard with 84% sensitivity and 91% specificity
     • Should include T1-weighted, T2-weighted, fat-saturated T2-weighted or STIR sequences
     • Best performed approximately one month after trauma to allow resolution of hemorrhage and edema
   • CT myelography: Alternative for detecting traumatic cervical nerve root avulsions
   • CT with IV contrast: When MRI is contraindicated
   • FDG-PET/CT: Helpful to differentiate radiation plexitis from tumor recurrence 1

3. Electrodiagnostic studies: Confirm clinical diagnosis and determine severity (neurapraxia, axonotmesis, or neurotmesis)

Treatment Approach

Treatment depends on the mechanism and severity of injury:

Conservative Management

• Indicated for neurapraxia and most cases of axonotmesis
• Most brachial plexus injuries (particularly those associated with shoulder dislocation) resolve spontaneously 2
• Physical therapy interventions include:
  • Kinesiotherapy: Range of motion exercises, muscle stretching, and strengthening
  • Electrothermal and phototherapy
  • Manual therapy
  • Sensory re-education strategies 3

Surgical Management

Surgical intervention is indicated when:

• Complete nerve rupture is present
• C7 nerve root avulsion with traumatic meningocele is identified
• No signs of recovery within 3-6 months 1

Surgical options include:

• Nerve grafting and transfers: Standard of care for traumatic brachial plexus injuries
• Neurolysis: Removal of scar tissue around intact nerves
• Free functional muscle transfers: Powerful tool to address elbow flexion and rudimentary grasp
• Tendon transfers and joint arthrodesis: For specific functional deficits 4

The optimal window for surgical intervention is within 1-3 months post-injury, with surgery recommended within 3-6 months if no signs of recovery are present 1, 2

Rehabilitation

Rehabilitation is crucial for maximizing functional recovery:

• Early phase: Pain control, gentle range of motion exercises within pain-free range
• Intermediate phase: Progressive strengthening of rotator cuff, scapular stabilizers, and core muscles
• Late phase: Sport-specific or activity-specific training with gradual return to full function 1

Prognosis

• Upper trunk injuries generally have better outcomes than lower trunk injuries
• Complete brachial plexus injuries have the poorest prognosis, especially for hand function
• Restoration of shoulder and elbow function is generally good with appropriate treatment
• Hand function recovery remains challenging in complete injuries 4

Prevention of Complications

• For radiation-induced brachial plexopathy:

  • Reduce radiation dose to the supraclavicular region
  • Exclude axillary region from treatment when possible
  • Use modern radiation techniques with precise targeting
  • Limit fractions to 2 Gy or less 1

• For athletes with overuse injuries:

  • Structured rehabilitation protocol
  • Gradual return to activity
  • Appropriate rest periods between activities 1