What is the appropriate workup for a patient with resolved numbness in the upper extremity (UE)?

Workup for Resolved Upper Extremity Numbness

For a patient with now-resolved upper extremity numbness, the primary goal is to determine stroke risk and identify any underlying compressive or vascular pathology that could recur, with the workup intensity determined by timing of symptom onset and associated features. 1

Immediate Risk Stratification Based on Timing

If symptoms occurred within the past 48 hours (even if now resolved), this represents a HIGH-RISK situation requiring same-day emergency evaluation:

• Patients with unilateral numbness within 48 hours carry a 10% risk of completed stroke within the first week, with highest risk in the initial 48 hours 1
• These patients require comprehensive evaluation by stroke expertise within 24 hours of first contact 1
• Do not be falsely reassured by symptom resolution—transient symptoms may represent a warning of impending stroke 1

Emergency Department Evaluation (if within 48 hours):

• Brain MRI with diffusion-weighted imaging (preferred) or CT head without contrast to rule out acute ischemic changes or hemorrhage 1
• CT angiography or MR angiography from aortic arch to vertex to evaluate for carotid and vertebral artery disease 1
• Carotid ultrasound to identify extracranial carotid stenosis >70% that may require endarterectomy 1
• Consider dual antiplatelet therapy (aspirin + clopidogrel 75 mg) for 21 days if symptomatic carotid stenosis is identified 1

Outpatient Workup (if symptoms occurred >48 hours ago and fully resolved)

Essential Clinical Assessment:

Vascular evaluation to exclude arterial insufficiency:

• Bilateral upper extremity blood pressure measurement to detect significant pressure differential suggesting subclavian stenosis 1
• Bilateral radial pulse palpation to assess for arterial compromise 1
• Resting ankle-brachial index (ABI) if there are any lower extremity symptoms, as correlation between upper and lower extremity vascular disease exists 2, 3

Neurological examination specifics:

• Assess for residual subtle deficits: light touch, pinprick, proprioception, and two-point discrimination in specific nerve distributions 4
• Test motor strength in median, ulnar, and radial nerve distributions 4
• Evaluate for signs of nerve entrapment: Tinel's sign at wrist and elbow, Phalen's maneuver for carpal tunnel syndrome 4, 5
• Document any cervical spine tenderness or limitation of range of motion 4

Imaging Strategy:

Duplex ultrasound of the upper extremity is the initial imaging modality if any concern for prior deep vein thrombosis:

• Sensitivity and specificity above 80% for upper extremity DVT 2
• Assess vein compressibility, flow patterns, and central venous obstruction 2
• Particularly important if patient has risk factors: indwelling catheters, pacemakers, cancer, hypercoagulability, or dialysis access 2, 3

Consider MRI cervical spine if symptoms suggest radiculopathy pattern (dermatomal distribution) or if physical examination reveals cervical pathology 5

Electrodiagnostic studies (NCS/EMG) when:

• Symptoms were in a specific nerve distribution (median, ulnar, or radial) 4, 5
• Physical examination cannot differentiate between carpal tunnel syndrome and cervical radiculopathy 5
• Neuromuscular ultrasound combined with NCS/EMG provides superior diagnostic accuracy in early or mild cases 5

Critical Pitfalls to Avoid

Do not dismiss resolved symptoms as benign without proper evaluation:

• Transient neurological symptoms may represent TIA or impending stroke requiring urgent intervention 1
• Female patients and those with severe preoperative upper extremity pain are at higher risk for persistent or recurrent numbness 6

Do not assume peripheral nerve entrapment without excluding central causes:

• Diabetes, smoking, alcohol, rheumatoid arthritis, and hypothyroidism are risk factors for bilateral nerve entrapment 4
• Unilateral symptoms in the absence of these risk factors should prompt evaluation for structural or vascular causes 4

Do not overlook upper extremity DVT:

• Catheter-associated thrombosis may be asymptomatic or present only as transient numbness 2
• Unilateral swelling (even if resolved) indicates obstruction at brachiocephalic, subclavian, or axillary level requiring investigation 2, 3

Follow-Up Protocol

• Reassess within 48-72 hours if initial workup is negative but symptoms were recent 3
• Formal re-evaluation at 6 weeks if any residual symptoms persist to detect delayed complications 3
• Patient education on stroke warning signs and instructions to seek immediate care if symptoms recur 1