What are the causes and treatments of hand numbness?

Hand Numbness: Causes and Treatment

Primary Diagnostic Approach

Hand numbness most commonly results from nerve compression syndromes, with carpal tunnel syndrome being the most frequent cause, followed by ulnar nerve entrapment, cervical radiculopathy, and less commonly thoracic outlet syndrome or systemic conditions. 1

Key Diagnostic Patterns by Distribution

Median nerve distribution (thumb, index, middle fingers):

• Carpal tunnel syndrome is the most common nerve entrapment condition, diagnosed by decreased pain sensation and numbness in the thumb, index, and middle fingers 1
• Symptoms are reproduced by wrist hyperflexion and median nerve percussion 1
• The palmar cutaneous branch can be damaged by repetitive trauma to the forearm and wrist 2

Ulnar nerve distribution (little finger and ulnar aspect of ring finger):

• Decreased sensation with intrinsic muscle weakness may indicate cervical radiculopathy, thoracic outlet syndrome, cubital tunnel syndrome (above elbow), or ulnar tunnel syndrome (at wrist) 1
• Electromyography and radiography help differentiate these conditions 1

Radial nerve distribution:

• Radial tunnel syndrome occasionally accompanies lateral epicondylitis 1
• A radial nerve block can help exclude concomitant radial tunnel syndrome in patients with tennis elbow symptoms 1

Critical Risk Factors to Assess

• Diabetes, smoking, alcohol consumption, rheumatoid arthritis, and hypothyroidism are risk factors for nerve entrapment, typically producing bilateral symptoms 1
• Approximately 40-50% of patients with thoracic outlet compression syndrome have associated peripheral nerve compression symptoms 3
• Only about 10% of patients with suspected thoracic outlet syndrome show objective evidence on examination, making it one of the most overlooked and misdiagnosed conditions 3

Treatment Algorithm

First-Line Conservative Management

For carpal tunnel syndrome and most compression neuropathies:

• Volar splinting is the initial treatment of choice 1
• Steroid injection often ameliorates symptoms 1
• Splints should be used consistently for at least 3 months for optimal benefit 4

For functional neurological causes:

• Encourage normal movement patterns and even weight-bearing in tasks 5
• Employ anxiety management and distraction techniques when undertaking tasks 5
• Avoid splinting that may prevent restoration of normal movement, as it can increase attention to the area and exacerbate symptoms 5

Second-Line Pharmacological Management

For neuropathic pain with numbness and tingling:

• Duloxetine is recommended for patients with neuropathic pain, numbness, and tingling 5
• Physical activity has been shown in multiple RCTs to improve neuropathic symptoms 5

For pain management:

• Topical NSAIDs are preferred over systemic treatments for safety reasons, especially for mild to moderate symptoms 5, 4
• Paracetamol (up to 4g/day) is the oral analgesic of first choice due to efficacy and safety 5, 4
• Oral NSAIDs should be used at the lowest effective dose and shortest duration in patients who respond inadequately to paracetamol 5, 4

Adjunctive Therapies

Physical modalities:

• Local application of heat (paraffin wax, hot packs) especially before exercise provides symptomatic relief 5, 4
• Exercise regimens involving both range of motion and strengthening exercises should be implemented 5, 4
• Acupuncture has demonstrated efficacy in decreasing pain intensity in multiple trials 5

Surgical Intervention

For severe refractory cases:

• Combined transaxillary first rib resection followed by immediate transcervical anterior and middle scalenectomy is the most complete procedure for thoracic outlet decompression, with approximately 93% of patients reporting improvement (95 of 102 surveyed) 3
• Surgery should be considered for severe thumb base osteoarthritis with marked pain and/or disability when conservative treatments have failed 5, 4

Critical Pitfalls to Avoid

• Do not overlook thoracic outlet syndrome - it presents with arm and hand numbness but shows objective findings in only 10% of cases, making it frequently misdiagnosed 3
• Distinguish between dialysis-associated steal syndrome and other causes - hand numbness in dialysis patients may indicate digital hypoperfusion ischemic syndrome, which can progress to tissue death if untreated 5
• Avoid prolonged immobilization - functional treatment is preferred over immobilization for most conditions 6
• Re-examine patients 3-5 days after initial presentation - examination may be limited by pain and inflammation during the first 48 hours 6
• Consider bilateral symptoms as indicators of systemic disease - diabetes, hypothyroidism, and rheumatoid arthritis typically produce bilateral nerve compression 1