What is the appropriate workup for a patient presenting with hand numbness?

Workup for Hand Numbness

Begin with plain radiographs (PA, lateral, and oblique views) of the affected hand/wrist as the initial imaging study, even when soft-tissue pathology is suspected, followed by a focused neurological examination to distinguish between peripheral nerve entrapment, cervical radiculopathy, and life-threatening central pathology. 1, 2

Immediate Red Flags Requiring Urgent Evaluation

Life-Threatening Conditions to Rule Out First

• Assess for bilateral hand involvement with ascending weakness, which suggests Guillain-Barré Syndrome (GBS) requiring immediate MRI of the entire spine, CSF analysis, and respiratory monitoring, as approximately 20% develop respiratory failure. 3

• Examine for upper motor neuron signs (hyperreflexia, clonus, extensor plantar responses) combined with bilateral hand numbness and burning dysesthesias in forearms, which indicates central cord syndrome requiring urgent cervical spine MRI without and with contrast and immediate neurosurgical consultation. 1, 3

• Check for lower extremity involvement alongside bilateral hand symptoms, which strongly suggests cervical myelopathy (C5-C7 cord lesion) demanding urgent neurosurgical referral. 1, 3, 2

• Evaluate for rapidly progressive weakness with areflexia/hyporeflexia, declining vital capacity, and dysautonomia, which are hallmarks of GBS requiring admission to a monitored setting. 3

• Consider stroke or TIA if sudden onset of unilateral hand numbness occurs, especially with vascular risk factors or other neurological signs. 2

Focused History Elements

Critical Questions to Ask

• Onset and progression: Sudden onset suggests vascular etiology; gradual onset over weeks suggests compression or neuropathy. 3, 2

• Distribution pattern: Dermatomal (cervical radiculopathy), peripheral nerve territory (median/ulnar/radial nerve), or stocking-glove (systemic neuropathy). 3, 2, 4

• Bilateral versus unilateral: Bilateral suggests central pathology, systemic neuropathy, or bilateral peripheral entrapment; unilateral suggests focal nerve compression or radiculopathy. 3, 2

• Associated symptoms: Weakness, burning dysesthesias, neck pain radiating to arm, or lower extremity symptoms. 1, 3, 5

• Preceding infection within 6 weeks (Campylobacter jejuni, CMV, Hepatitis E, Mycoplasma, EBV, Zika) suggests GBS. 3

• Medical comorbidities: Diabetes (peripheral neuropathy), chronic kidney disease (uremic neuropathy), hepatitis C (HCV-related neuropathy), recent chemotherapy (CIPN), or dialysis access (steal syndrome). 3, 2

Physical Examination Algorithm

Neurological Assessment Sequence

Step 1: Sensory Testing

• Perform dermatomal sensory testing with pinprick, light touch, and two-point discrimination in C5-T1 distributions to identify cervical radiculopathy patterns. 2, 4, 5

• Test peripheral nerve territories: Median nerve (thumb, index, middle fingers), ulnar nerve (ring and small fingers), and radial nerve (first dorsal web space). 4, 5

• Assess for stocking-glove distribution starting distally, which suggests diabetic or other systemic neuropathy. 3

Step 2: Motor Examination

• Test key muscle groups: C5 (deltoid), C6 (biceps, wrist extensors), C7 (triceps, finger extensors), C8 (finger flexors), T1 (finger abductors). 1, 4

• Grade strength on 0-5 scale; asymmetric weakness suggests focal pathology rather than systemic neuropathy. 1, 4

Step 3: Reflex Testing

• Check deep tendon reflexes: Biceps (C5-C6), brachioradialis (C6), triceps (C7). 3, 4

• Assess for hyperreflexia, clonus, or extensor plantar responses, which indicate upper motor neuron pathology requiring urgent imaging. 3, 2

Step 4: Provocative Maneuvers

• Tinel's sign at wrist (tapping over median nerve) and Phalen's maneuver (wrist flexion for 60 seconds) for carpal tunnel syndrome. 2, 6, 4

• Spurling's test (neck extension with lateral rotation and axial compression) for cervical radiculopathy. 4, 5

Imaging Pathway

Initial Imaging

Obtain three-view plain radiographs (PA, lateral, oblique) of the hand/wrist first, even when soft-tissue pathology is suspected, to exclude bony abnormalities and establish baseline assessment. 1, 2

Advanced Imaging Indications

• MRI of cervical spine without and with contrast is mandatory if upper motor neuron signs, bilateral symptoms with lower extremity involvement, or progressive weakness are present. 1, 3, 2

• MRI of hand/wrist without contrast should be reserved for cases where ultrasound is inconclusive, symptoms persist despite conservative measures for 4-6 weeks, or detailed soft-tissue evaluation is required. 1, 2

• Arteriography from aortic arch to palmar arch is indicated only for dialysis patients with arteriovenous access presenting with hand ischemia or numbness suggestive of steal syndrome. 2

Imaging Pitfalls to Avoid

• Do not skip initial plain radiographs even when clinical presentation appears purely soft-tissue related, as this may miss occult bony pathology. 1, 2

• Do not use MRI as first-line imaging for hand numbness, as it is not cost-effective and not supported by ACR guidelines. 1, 2

Laboratory and Electrodiagnostic Testing

Laboratory Workup Based on Clinical Suspicion

• For suspected GBS: CSF analysis showing increased protein with normal cell count (albuminocytologic dissociation). 3

• For diabetic neuropathy: Hemoglobin A1c, fasting glucose; test temperature/pinprick sensation and vibration with 128-Hz tuning fork. 3

• For uremic neuropathy: Creatinine, eGFR, urinalysis. 3

• For inflammatory arthritis: ESR, CRP, rheumatoid factor, anti-citrullinated protein antibodies. 6

• For chemotherapy-induced neuropathy: Review recent chemotherapy history (taxane-based or platinum-based agents). 3

Electrodiagnostic Studies

Nerve conduction studies and EMG are indicated if symptoms persist beyond 4-6 weeks despite conservative measures, to confirm peripheral nerve entrapment and guide surgical planning. 2, 4

Management Based on Etiology

Peripheral Nerve Entrapment (Carpal Tunnel Syndrome)

• Initial conservative management: Occupational therapy for ergonomic modifications, wrist splinting in neutral position, and activity modification. 2, 4

• Pharmacologic treatment: Topical NSAIDs as first-line for mild-to-moderate pain. 6

• Surgical referral if conservative measures fail after 4-6 weeks or if severe weakness/thenar atrophy is present. 2, 4

Cervical Radiculopathy

• Conservative management has favorable prognosis with up to 75% improvement; includes physical therapy, NSAIDs, and activity modification. 2

• Selective nerve root blocks can target specific nerve root pain if conservative measures fail. 2

Peripheral Neuropathy

Duloxetine is first-line pharmacologic treatment for peripheral neuropathy with numbness and tingling. 3

• Additional options: Pregabalin, gabapentin, tricyclic antidepressants for painful neuropathy. 3

• Non-pharmacologic: Physical activity, acetaminophen, NSAIDs, acupuncture for associated pain. 3

• For diabetic neuropathy: Improved glycemic control prevents progression but does not reverse neuronal loss; consider nerve repair agents, antioxidants, and improved microcirculation agents. 3

Referral Indications

Urgent Neurosurgical Consultation

• Suspected cervical myelopathy with bilateral hand numbness and lower extremity symptoms. 2

• Central cord syndrome with upper motor neuron signs. 1, 3

Neurology Referral

• Suspected GBS with progressive weakness and areflexia. 3

• Suspected focal dystonia or signs of motor neuron disease. 6

Vascular Surgery Referral

• Dialysis patients with hand ischemia or numbness requiring arteriographic evaluation for steal syndrome. 2

Hand Surgery Referral

• Severe structural abnormalities or refractory carpal tunnel syndrome. 6

Rheumatology Referral

• Suspected inflammatory arthritis (rheumatoid arthritis, psoriatic arthritis). 6

Common Pitfalls to Avoid

• Do not assume unilateral presentations are bilateral symmetric neuropathy patterns (chemotherapy-induced or diabetic neuropathy). 2

• Do not delay urgent imaging if any red flags for central pathology are present (bilateral symptoms, upper motor neuron signs, lower extremity involvement). 3, 2

• Do not overlook respiratory monitoring in suspected GBS, as 20% develop respiratory failure. 3

• Do not perform advanced imaging before plain radiographs unless life-threatening central pathology is suspected. 1, 2