What could be causing left upper arm pain, numbness in both hands, and sharp pain starting from the left shoulder, accompanied by new onset heartburn, with a normal electrocardiogram (EKG) and no signs of redness, swelling, or abnormal auscultation?

Clinical Assessment: Left Upper Arm Pain with Bilateral Hand Numbness and New Heartburn

Most Likely Diagnosis

This presentation most strongly suggests cervical radiculopathy with referred shoulder pain, potentially complicated by concurrent gastroesophageal reflux disease (GERD). The combination of left upper arm pain radiating from the shoulder, bilateral hand numbness, and sharp pain triggered by touch are hallmark symptoms of cervical nerve root compression rather than primary shoulder pathology 1. The normal EKG effectively rules out acute coronary syndrome as the cause of the arm pain and new heartburn 2.

Key Diagnostic Reasoning

Why Cervical Radiculopathy is Primary

• Bilateral hand numbness is the critical distinguishing feature - this cannot be explained by isolated shoulder pathology and strongly indicates cervical spine involvement with nerve root compression 1
• Pain radiating from the left shoulder down the arm follows a dermatomal pattern characteristic of cervical radiculopathy, most commonly from herniated discs or osteophytes causing nerve root compression 1
• Sharp pain triggered by touch (allodynia) suggests neuropathic pain with peripheral or central sensitization, which is typical of nerve compression rather than musculoskeletal shoulder injury 1
• The 2-week duration qualifies this as subacute, allowing time for nerve compression symptoms to fully manifest 2

Why Cardiac Causes are Excluded

• Normal EKG effectively rules out acute coronary syndrome in this presentation 2
• While chest pain can radiate to shoulders, arms, jaw, neck, and upper abdomen 2, the bilateral hand numbness and sharp pain with palpation are not consistent with cardiac ischemia 2
• The absence of exertional component, relief with rest, or response to nitroglycerin further argues against angina 2

The Heartburn Component

• New onset heartburn occurring simultaneously with arm pain warrants attention but is likely a separate issue rather than cardiac in origin given the normal EKG 2
• GERD commonly presents with epigastric pain and heartburn, and symptoms can overlap with other conditions 2
• Functional heartburn or esophageal hypersensitivity can occur independently and may be exacerbated by stress or pain from the primary cervical condition 3, 4, 5

Immediate Diagnostic Workup Required

First-Line Imaging (Mandatory)

Obtain MRI of the cervical spine without contrast as the preferred initial advanced imaging when clinical examination supports radiculopathy, as it directly visualizes disc herniations, osteophytes, and nerve root compression 1. This should be ordered urgently given the bilateral neurological symptoms 1.

Plain radiographs of the cervical spine may be obtained first to assess for gross structural abnormalities, degenerative changes, or alignment issues, though they cannot visualize disc herniations or nerve roots 1.

Additional Testing if Imaging is Equivocal

• Electrodiagnostic testing (EMG/NCS) should be considered if imaging is negative or equivocal, with sensitivity over 80% and specificity of 95% for confirming nerve compression and localizing the level 1

Shoulder Imaging (Secondary Priority)

Standard shoulder radiographs (3 views minimum: AP in internal and external rotation, plus axillary or scapula-Y view) should be obtained to rule out concurrent shoulder pathology 2, 6. However, the bilateral hand numbness makes isolated shoulder pathology unlikely as the primary diagnosis 1.

Shoulder MRI is recommended only if physical examination suggests concurrent rotator cuff pathology after cervical spine evaluation 1.

Management Algorithm

Immediate Pain Management

1. Acetaminophen as first-line, maximum 4 grams daily 6
2. Topical agents (methyl salicylate, capsaicin cream, or menthol) as second-line for mild-moderate pain 6
3. Nerve-stabilizing agents such as pregabalin (300-600 mg daily in divided doses), gabapentin, or duloxetine for neuropathic pain management if cervical radiculopathy is confirmed 1

For the Heartburn Component

• Empirical proton pump inhibitor (PPI) therapy for 4-8 weeks is the most cost-effective approach for new onset heartburn with normal cardiac workup 2
• Consider H. pylori testing (13C-urea breath test or stool antigen test) if symptoms persist after PPI trial 2

Specialist Referrals

Urgent neurology or spine specialist referral is indicated for:

• Bilateral neurological symptoms (present in this case) 1
• Progressive weakness or sensory loss 6
• Failure to improve with conservative management 1

Physical therapy referral should include:

• Range of motion exercises 6
• Scapular stabilization exercises 6
• Cervical spine-specific rehabilitation if radiculopathy confirmed 1

Critical Pitfalls to Avoid

• Do not assume this is "simple muscle tension" or "muscle spasm" without ruling out structural cervical spine pathology - imaging should not be delayed 1
• Do not attribute bilateral hand numbness to shoulder pathology alone - this mandates cervical spine evaluation 1
• Do not dismiss the heartburn as purely cardiac after normal EKG, but do not ignore it either - treat empirically with PPI while focusing on the primary neurological issue 2
• Do not delay imaging in the presence of bilateral neurological symptoms - this represents a red flag requiring prompt evaluation 1, 6