What is the initial workup for a patient with intermittent arm numbness for 2 weeks?

Initial Workup for Intermittent Arm Numbness for 2 Weeks

Patients with intermittent arm numbness for 2 weeks should undergo brain imaging, non-invasive vascular imaging, ECG, and laboratory investigations within 2 weeks of first contact with the healthcare system to rule out stroke and other serious neurological conditions.

Risk Stratification

The first step in the workup is to determine the risk level based on presenting symptoms:

Very High Risk (Urgent Evaluation)

If the arm numbness is accompanied by:

• Unilateral weakness (face, arm, and/or leg)
• Speech disturbance/aphasia
• Fluctuating symptoms

These patients should be:

• Immediately sent to an emergency department with advanced stroke care capabilities 1
• Undergo urgent brain imaging (CT or MRI) and non-invasive vascular imaging (CTA or MRA from aortic arch to vertex) within 24 hours 1
• Have an ECG completed without delay 1

Moderate Risk (Expedited Evaluation)

For patients with:

• Isolated sensory symptoms like arm numbness without motor weakness or speech disturbance
• Symptoms present between 48 hours and 2 weeks

These patients should receive:

• Comprehensive clinical evaluation by a healthcare professional with stroke expertise
• Investigations completed within 2 weeks of first contact 1

Lower Risk (Routine Evaluation)

For patients with:

• Atypical sensory symptoms (patchy numbness/tingling)
• Symptoms present for more than 2 weeks

These patients should be seen by a neurologist or stroke specialist within one month 1

Required Investigations

Imaging Studies

1. Brain Imaging:

   • CT or MRI of the brain 1

2. Vascular Imaging:

   • CT angiography (CTA) from aortic arch to vertex (preferred) 1
   • Alternatives: MR angiography or carotid ultrasound (for extracranial imaging) 1

Laboratory Tests

• Complete blood count
• Electrolytes
• Coagulation studies (aPTT, INR)
• Renal function (creatinine, eGFR)
• Random glucose or HbA1c
• Troponin 1

Cardiac Assessment

• 12-lead ECG 1

Additional Considerations

Cervical Spine Evaluation

If vascular and brain imaging are negative, consider:

• Cervical spine imaging to evaluate for cervical spondylotic radiculopathy, which can cause arm numbness 2
• Electrodiagnostic studies (EMG/NCS) to evaluate for peripheral nerve compression syndromes 3, 4

Neurological Examination Focus Points

• Distribution of numbness (dermatome vs peripheral nerve pattern)
• Associated weakness or reflex changes
• Presence of neck pain or radicular symptoms
• Exacerbating factors (e.g., neck position, repetitive activities)

Common Pitfalls to Avoid

1. Failing to recognize TIA/stroke: Intermittent arm numbness can be a manifestation of TIA or stroke, especially when accompanied by other neurological symptoms. Don't dismiss as musculoskeletal without appropriate vascular imaging 1.

2. Missing double crush syndrome: Patients may have both cervical nerve root compression and peripheral nerve entrapment contributing to symptoms 4.

3. Inadequate follow-up: Ensure appropriate follow-up is arranged based on risk stratification, even if initial symptoms seem minor 5.

4. Overlooking Guillain-Barré syndrome: In cases with progressive symptoms, consider GBS which may initially present with sensory symptoms before motor involvement 1.

5. Attributing symptoms to previous injury: Careful history is needed to distinguish new neurological symptoms from chronic conditions 5.