Causes of Thoracic Pain
Thoracic pain arises from a broad spectrum of etiologies that can be categorized into musculoskeletal, visceral (cardiac, pulmonary, gastrointestinal, vascular), inflammatory/infectious, and neoplastic causes, with musculoskeletal origins being most common in ambulatory settings while life-threatening cardiovascular and pulmonary causes must be excluded first.
Life-Threatening Causes to Exclude Immediately
The initial priority is ruling out acute life-threatening conditions 1, 2:
- Cardiovascular: Acute coronary syndrome/myocardial infarction, aortic dissection, pericarditis
- Pulmonary: Pulmonary embolism (found in 5-21% of emergency department presentations with pleuritic chest pain), tension pneumothorax
- Vascular: Aortic dissection
These require immediate assessment with electrocardiography, troponin assays, and chest radiography 2.
Musculoskeletal Causes (Most Common in Ambulatory Settings)
Musculoskeletal causes account for 42-51% of nontraumatic chest pain after exclusion of other etiologies 1:
- Costochondritis (42% of musculoskeletal chest wall pain) - diagnosed by physical examination without imaging 1
- Chest wall syndrome affecting bones, cartilage, joints, ligaments, tendons, muscles
- Thoracic spine pathology: degenerative disease, compression fractures (especially in patients >65 years or on chronic steroids), inflammatory conditions 3
- Sternoclavicular and manubriosternal joint involvement (affects up to 50% of axial spondyloarthritis patients) 1
- Intercostal neuralgia 4
- Myalgia epidemica 4
Pulmonary Causes
- Pleuritis and pneumonia 4, 2
- Pulmonary embolism (use validated clinical decision rules to guide d-dimer, V/Q scan, or CT angiography) 2
- Pneumothorax 4, 2
- Pulmonary hypertension 4
Infectious/Inflammatory Causes
- Herpes zoster 4
- Viral pleuritis: Coxsackieviruses, RSV, influenza, parainfluenza, mumps, adenovirus, CMV, EBV 2
- Mediastinitis 4
- Osteomyelitis 1
- Axial spondyloarthritis (ankylosing spondylitis, psoriatic spondylitis, reactive arthritis, inflammatory bowel disease-related) 3
Gastrointestinal Causes
- Gastroesophageal reflux disease (20-50% prevalence in noncardiac chest pain) 5
- Esophageal motor disorders 5
- Esophageal visceral hyperalgesia 5
Neoplastic/Metabolic Causes
The thoracic spine is a common site for 3:
- Metastatic disease
- Primary bone tumors
- Osteoporotic compression fractures (particularly in elderly or steroid users)
- Osteonecrosis 1
Other Visceral Causes
Critical Red Flags Requiring Early Imaging
Immediate imaging is warranted for 3:
- Significant trauma
- Myelopathy
- Prior thoracic spine fusion
- Known osteoporosis or age >65 years
- Chronic steroid use
- Suspected malignancy, fracture, or infection
- Symptomatic spinal canal stenosis or cord compression
Common Pitfalls
- Assuming musculoskeletal origin without excluding cardiac/pulmonary emergencies - always rule out life-threatening causes first
- Imaging uncomplicated acute thoracic back pain too early - most cases are self-limited and don't require imaging unless red flags present or no improvement after 4-6 weeks of conservative management 3
- Missing anterior chest wall pain as first manifestation of axial spondyloarthritis (occurs in 4-6% of cases) 1
- Failing to document radiographic resolution in pneumonia patients - repeat chest X-ray at 6 weeks is essential, especially in smokers and those >50 years 2