Can neuropathy occur under the arms?

Neuropathy Under the Arms: Brachial Plexus Involvement and Prevention

Yes, neuropathy can occur under the arms, specifically involving the brachial plexus, which can be affected by compression, stretching, or positioning during medical procedures or due to other causes.

Brachial Plexus Neuropathy in the Axillary Region

• Brachial plexus injuries can occur when the nerves passing through the axillary (underarm) region are compressed or stretched, particularly during surgical procedures or due to positioning 1
• Case reports document brachial plexus injuries occurring with arm abduction greater than or equal to 90° in various positions including supine, prone, lithotomy, and Trendelenburg positions 1
• Chest ("axillary") rolls placed under the dependent lateral thorax in laterally positioned patients are specifically recommended to decrease the risk of brachial plexus neuropathy in the down arm 1

Risk Factors for Axillary Region Neuropathy

• Improper positioning during surgical procedures, particularly with arm abduction exceeding 90° 1
• Use of shoulder braces in steep head-down positions 1
• Improper use of automated blood pressure cuffs on the arm 1
• Prolonged compression of the axillary region 1
• Diabetes mellitus significantly increases risk of compression neuropathies throughout the body, including the axillary region 2, 3

Prevention Strategies for Axillary Neuropathy

• When possible, limit arm abduction in supine patients to 90° to reduce brachial plexus strain 1
• Use padded armboards to decrease the risk of upper extremity neuropathy 1
• Implement chest rolls in laterally positioned patients to decrease pressure on the brachial plexus 1
• Avoid the use of shoulder braces in steep head-down positions 1
• Periodically assess upper extremity position during procedures (recommended by 92% of consultants and 97% of ASA members) 1
• Avoid improper use of automated blood pressure cuffs on the arm 1

Clinical Manifestations of Axillary Neuropathy

• Symptoms may include numbness, paresthesia, weakness, and pain in the affected arm 3, 4
• Paresthesia/dysesthesia (abnormal sensations) are the most commonly reported symptoms in brachial plexus injuries 4
• Pain intensity correlates with upper limb functional impairment (r=0.60, P<0.001) 4
• Symptoms may follow specific nerve distribution patterns rather than dermatomal patterns 2

Diagnostic Approach

• Detailed clinical evaluation of sensory and motor symptom distribution is fundamental for diagnosis 2
• Electrophysiological studies (EMG and nerve conduction studies) can help identify the specific nerves involved 2, 3
• MRI may show enlargement of the trunks, cords, and terminal branches of the brachial plexus in acute cases 5
• Early postoperative physical assessment within 24 hours can help detect upper limb neuropathies that may have occurred during procedures 1

Treatment Considerations

• Supportive care is the mainstay of treatment for brachial plexus neuropathy 6
• Steroids may help relieve pain in acute stages but do not appear to alter the overall prognosis 6
• Recovery rate in brachial plexus neuropathy is generally good, with approximately 90% recovery at 3 years 6
• Addressing modifiable risk factors such as smoking and alcohol consumption may be beneficial, as these have been associated with development of neuropathic pain after brachial plexus injuries 4

Special Considerations

• Total brachial plexus injuries and avulsions are associated with higher risk of developing neuropathic pain 4
• Recent research into axon degeneration mechanisms involving SARM1 pathways may lead to new therapeutic approaches for preventing and treating peripheral neuropathies 7
• Patients with neuropathic pain experience significantly poorer function of the upper limbs as measured by standardized assessments 4