What are the differential diagnoses and initial management steps for a patient presenting with right hand pain and swelling, accompanied by burning pain radiating up the arm into the shoulder and right chest?

Differential Diagnoses for Right Hand Pain and Swelling with Burning Pain Radiating to Arm, Shoulder, and Right Chest

The most critical priority is to immediately rule out acute coronary syndrome (ACS), as right arm involvement with chest pain strongly suggests myocardial infarction—among 51 patients with right arm pain radiation, 48 had coronary disease and 41 had active MI. 1

Life-Threatening Causes Requiring Immediate Evaluation

Acute Coronary Syndrome (STEMI/NSTEMI/Unstable Angina)

• Right arm radiation is highly specific for MI and must be excluded first, with the largest pain extension reported in MI patients 1
• Presents with retrosternal pressure building gradually over minutes, radiating to arm/jaw/neck, associated with diaphoresis, dyspnea, nausea, or syncope 2, 3
• Women may describe pain as "tearing," "terrifying," or "intolerable" and experience nausea/vomiting more frequently than men 4
• Obtain ECG immediately—even at early stages, ECG is seldom normal; look for ST-segment elevations or new left bundle-branch block 2
• Do not wait for cardiac biomarkers (troponins, CK-MB) to initiate treatment if clinical suspicion is high 2

Aortic Dissection

• Sudden-onset "ripping" or "tearing" chest pain radiating to upper or lower back 2, 3
• Pulse differentials between extremities, blood pressure differentials >20 mmHg, or new aortic regurgitation murmur 2
• Pain described as abrupt/instantaneous in onset and severe in intensity establishes high pretest probability 2

Pulmonary Embolism

• Acute dyspnea with pleuritic chest pain, tachycardia (present in >90%), tachypnea 3
• Associated risk factors (immobilization, recent surgery, malignancy) 3

Serious Non-Immediately Fatal Causes

Complex Regional Pain Syndrome (CRPS) Type I

• Burning pain with swelling of hand/wrist is characteristic of CRPS, which can develop after trauma, stroke, or even mild traumatic brain injury 5, 6
• Clinical features include: spontaneous burning pain, mechanical hyperalgesia, vasodilation, skin temperature asymmetries, skin color changes, swelling, motor weakness 6
• May show hot uptake on three-phase bone scan in delayed images 6
• Diagnosis is clinical with no specific pathognomonic tests 5
• Can develop as exaggerated inflammatory response with neurogenic inflammation causing edema, vasodilation, and hyperhidrosis 5

Cervical Radiculopathy

• Insidious onset of pain and paresthesias from neck/shoulder to lateral forearm and hand 7
• Pain follows dermatomal distribution corresponding to nerve root compression 7
• May respond to manual cervical traction, spinal manipulation, and neuromobilization 7

Myofascial Referred Pain

• Active trigger points (particularly infraspinatus muscle) can produce upper extremity symptoms mimicking radiculopathy 7
• Pain pattern may be similar to radicular pain but does not follow strict dermatomal distribution 7
• Responds to manual trigger point therapy and functional postural exercises 7

Common Benign Causes

Costochondritis/Chest Wall Pain

• Tenderness of costochondral joints on palpation, pain reproducible with chest wall pressure 3
• Localized to limited area, affected by palpation, breathing, turning, twisting, or bending 3

Pericarditis

• Sharp, pleuritic chest pain worsening when supine, improving when leaning forward 3
• Friction rub on examination, fever 3

Critical Diagnostic Algorithm

Step 1: Immediate Cardiac Evaluation

• Obtain 12-lead ECG within 10 minutes of presentation 2
• Look for ST-segment elevations, new Q-waves, or left bundle-branch block 2
• Assess for autonomic activation: pallor, sweating, hypotension, narrow pulse pressure 2
• Check for pulse/blood pressure differentials between arms to exclude aortic dissection 2

Step 2: Risk Stratification Based on Pain Characteristics

High-risk features suggesting ACS:

• Gradual onset over minutes (not seconds) 2, 3
• Retrosternal pressure/heaviness/squeezing quality 2, 3
• Radiation to right arm (highly specific for MI) 1
• Wide extension of pain involving multiple areas 1
• Associated diaphoresis, nausea, dyspnea, or syncope 2, 3

Features suggesting non-cardiac etiology:

• Sharp pain increasing with inspiration 3
• Fleeting pain lasting only seconds 3
• Pain localized to very small area 3
• Pain reproducible with palpation 3

Step 3: If Cardiac Causes Excluded, Evaluate for CRPS

• Assess for burning quality of pain with swelling 5, 6
• Check for skin temperature asymmetries, color changes, vasodilation 6
• Evaluate for mechanical hyperalgesia and motor weakness 6
• Consider three-phase bone scan showing hot uptake in delayed images 6
• Assess for preceding trauma, stroke, or neurological injury 5, 6

Step 4: Distinguish Radicular vs. Referred Pain

• Cervical radiculopathy follows dermatomal distribution with specific nerve root findings 7
• Myofascial referred pain does not follow strict dermatomal patterns and has identifiable trigger points 7
• Physical examination can differentiate between these etiologies 7

Critical Pitfalls to Avoid

• Never use nitroglycerin response as diagnostic criterion—esophageal spasm and other conditions also respond to nitroglycerin 2, 3
• Do not dismiss atypical presentations in women, elderly, or diabetic patients—they frequently present without classic chest pain 2, 4
• Do not rely on pain severity to determine urgency—severity is poor predictor of complications 4
• Do not wait for cardiac biomarkers if clinical suspicion for MI is high—initiate treatment immediately 2
• Recognize that normal chest X-ray does not exclude aortic dissection—up to 16% are normal 2

High-Risk Patient Populations Requiring Lower Threshold for Cardiac Workup

• Age >75 years with accompanying dyspnea, syncope, acute delirium, or unexplained fall 3
• Women presenting with atypical symptoms (nausea, fatigue, dyspnea predominating over chest pain) 2, 3
• Patients with diabetes, renal insufficiency, or dementia 3
• Previous history of coronary artery disease 2