Differential Diagnosis for Muscle Pain in Chest and Back

Immediate Life-Threatening Conditions to Exclude First

The American Heart Association recommends excluding life-threatening conditions through focused examination and ECG within 10 minutes of presentation in patients with chest and back pain 1, 2

Acute Coronary Syndrome presents with retrosternal pressure building gradually over minutes, radiating to left arm/jaw/neck, associated with diaphoresis, dyspnea, or nausea, and examination may be completely normal in uncomplicated cases 1, 2, 3
Pericarditis is characterized by sharp, pleuritic chest pain worsening when supine and improving when leaning forward, with friction rub on examination and fever 1, 2, 3
Myocarditis is associated with chest pain, fever, signs of heart failure, and S3 gallop 2

Aortic Dissection is a sudden-onset "ripping" or "tearing" chest or back pain, with pulse differentials between extremities, blood pressure differentials >20 mmHg, or new aortic regurgitation murmur 1, 2, 4
Pulmonary Embolism presents with acute dyspnea, pleuritic chest pain, tachycardia, and tachypnea 1, 2, 3

Esophageal Rupture is associated with a history of emesis, subcutaneous emphysema, pneumothorax, and unilateral decreased or absent breath sounds 1, 2
Pneumothorax is characterized by dyspnea and pain on inspiration with unilateral absence of breath sounds 1, 2

Costochondritis/Tietze Syndrome is tenderness of costochondral joints on palpation, with pain reproducible with chest wall pressure 1, 2, 3
The American College of Physicians recommends assessing for fleeting pain lasting only seconds, which is unlikely to be cardiac 6

The American Heart Association advises against using nitroglycerin response as a diagnostic criterion, as esophageal spasm and other non-cardiac conditions also respond to nitroglycerin 5, 3, 7
The American College of Cardiology recommends not dismissing chest pain in women, elderly patients, or patients with diabetes, as they frequently present with atypical symptoms including sharp or positional pain 5, 3, 7

A thorough history should include exact onset, duration, quality, and severity of pain, as well as radiation pattern, precipitating factors, and associated symptoms 1, 5, 6
The American Heart Association recommends a focused cardiovascular examination for murmurs, friction rub, S3, pulse differentials, and blood pressure differentials 1, 5
An ECG should be performed within 10 minutes to evaluate for ST-segment elevation, new Q waves, or T-wave inversions 5, 2

The American College of Physicians recommends monitoring for red flags requiring immediate referral, including age ≥75 years with accompanying dyspnea, syncope, acute delirium, or unexplained fall 5, 7
Elevated cardiac troponin levels, pulse differentials, blood pressure differentials >20 mmHg, or new murmurs require immediate referral 5, 2, 1, 4