What are causes of rib cage pain

It is helpful to distinguish between six life-threatening causes of rib cage pain and other more common indolent causes ¹, ², ³, ⁴, ⁵, ⁶. Sudden blockage in a lung artery (pulmonary embolism), heart attack (myocardial infarction), inflammation and swelling of the covering of the heart (pericarditis), aortic dissection (tear in the wall of the inner layer of the aorta), pneumonia, and collapsed lung (pneumothorax) are the six serious conditions that must be initially considered ⁷. The differential diagnosis is presented in Table 1.

Cardiac disease is the leading cause of death in the United States, yet only 1.5 percent of patients presenting to their family doctor with chest pain will have unstable angina or an acute heart attack (myocardial infarction) ⁸. The most common causes of chest pain in the primary care population include chest wall pain (20 percent); reflux esophagitis (13 percent); and costochondritis (13 percent) ⁸, although in practice, costochondritis is often included in the chest wall pain category ⁹. Other considerations include pulmonary (e.g., pneumonia, pulmonary embolism), gastrointestinal (e.g., gastroesophageal reflux disease [GERD]), and psychological (e.g., anxiety, panic disorder) etiologies, and cardiovascular disorders (e.g., acute congestive heart failure, acute thoracic aortic dissection). Table 2 lists the differential diagnosis of chest pain ¹⁰, ¹¹, ¹², ¹³.

Table 1. Potential causes of rib cage pain

Origin	Causes
Cardiac	Acute coronary syndrome, congestive heart failure, pericarditis, postcardiac injury syndrome, postmyocardial infarction syndrome, postpericardiotomy syndrome
Gastrointestinal	Inflammatory bowel disease, pancreatitis, spontaneous bacterial pleuritis
Hematologic/Oncologic	Malignancy, malignant pleural effusion, sickle cell crisis
Iatrogenic/Exposure	Asbestosis, cardiothoracic surgery, medications, pericardiocentesis
Infection	Abscess
		Liver, pulmonary, splenic
	Bacterial
		Empyema
		Legionnaires’ disease
		Mediterranean spotted fever (caused by a rickettsial organism [Rickettsia conorii] endemic to the Mediterranean region of Europe that triggers a syndrome similar to Rocky Mountain spotted fever in the United States), parapneumonic pleuritic pneumonia, tuberculosis
	Myocarditis
	Parasitic
		Amebiasis, paragonimiasis
	Viral
		Adenovirus, coxsackieviruses, cytomegalovirus, Epstein-Barr virus, herpes zoster, influenza, mumps, parainfluenza, respiratory syncytial virus
Inflammatory/autoimmune/Genetic	Ankylosing spondylitis, collagen vascular diseases, familial Mediterranean fever, fibromyalgia, reactive eosinophilic pleuritis, rheumatoid arthritis, systemic lupus erythematosus
Pulmonary	Chronic obstructive pulmonary disease, hemothorax, pleural adhesions, pneumothorax, pulmonary embolism
Renal	Chronic renal failure, renal capsular hematoma
Rheumatologic	Lupus pleuritis, rheumatoid pleuritis, Sjögren syndrome

[Source ⁷ ]

Table 2. Differential Diagnosis of Chest Pain

Diagnosis	Clinical findings	LR+	LR–
Acute myocardial infarction 11	Chest pain radiates to both arms	7.1	0.67
	Third heart sound on auscultation	3.2	0.88
	Hypotension	3.1	0.96
Chest wall pain 14	At least two of the following findings: localized muscle tension; stinging pain; pain reproducible by palpation; absence of cough	3.0	0.47
Gastroesophageal reflux disease 15	Burning retrosternal pain, acid regurgitation, sour or bitter taste in the mouth; one-week trial of high-dose proton pump inhibitor relieves symptoms	3.1	0.30
Panic disorder/anxiety state 16	Single question: In the past four weeks, have you had an anxiety attack (suddenly feeling fear or panic)?	4.2	0.09
Pericarditis 10	Clinical triad of pleuritic chest pain (increases with inspiration or when reclining, and is lessened by leaning forward), pericardial friction rub, and electrocardiographic changes (diffuse ST segment elevation and PR interval depression without T wave inversion)	NA	NA
Pneumonia 1	Egophony	8.6	0.96
	Dullness to percussion	4.3	0.79
	Fever	2.1	0.71
	Clinical impression	2.0	0.24
Heart failure 12	Pulmonary edema on chest radiography	11.0	0.48
	Clinical impression/judgment	9.9	0.65
	History of heart failure	5.8	0.45
	History of acute myocardial infarction	3.1	0.69
Pulmonary embolism 17	High pretest probability based on Wells criteria	6.8	1.8
	Moderate pretest probability based on Wells criteria	1.3*	0.7
	Low pretest probability based on Wells criteria	0.1	7.6
Acute thoracic aortic dissection 13	Acute chest or back pain and a pulse differential in the upper extremities	5.3	NA

Footnote:

The higher the LR (likelihood ratio) is above 1, the better it rules in disease (greater than 10 is considered good). Conversely, the lower the LR (likelihood ratio) is below 1, the better it rules out disease (less than 0.1 is considered good).

LR+ = positive likelihood ratio; LR– = negative likelihood ratio; NA = not available.

*—Does not change posttest probability.

[Source ⁹ ]

Studies of rib cage pain have shown that pulmonary embolism is the most common life-threatening cause and the source of the pain 5% to 21% of the time ¹⁸. A recent prospective trial of 7,940 patients evaluated for pulmonary embolism revealed that pleuritic-type chest pain was significantly associated with confirmed pulmonary embolism ¹⁹. The most commonly occurring symptoms of pulmonary embolism were shortness of breath (dyspnea) and pleuritic chest pain in 73% and 66% of patients, respectively ¹⁸.

Doctors often evaluate patients for myocardial infarction (heart attack) and coronary artery disease using electrocardiography (EKG or ECG) and troponin levels. Applying a five-point validated clinical decision rule helps improve diagnostic accuracy for coronary artery disease (Table 3) ²⁰. The presence of zero or one of the five scored items predicted only a 1% likelihood of coronary artery disease, whereas 63% of patients with four or five of these factors had coronary artery disease ²⁰. Additionally, high-sensitivity cardiac troponin levels can help improve diagnostic accuracy for myocardial infarction ²¹.

Table 3. Validated Clinical Decision Rule for Likelihood of Coronary Artery Disease as a Cause of Chest Pain

Component			Points
Age and sex (male 55 years or older or female 65 years or older)			1
Known vascular disease (coronary artery disease, occlusive vascular disease, cerebrovascular disease)			1
Pain is not elicited with palpation			1
Pain is worse with exercise			1
Patient assumes pain is of cardiac origin			1
Likelihood of coronary artery disease as cause of chest pain
Total score	Positive likelihood ratio	Negative likelihood ratio
0 or 1	1.09	0.00
2 or 3	1.83	0.03
4 or 5	4.52	0.15

Footnote: Patients with chest pain and a score of 4 or 5 should undergo urgent evaluation for coronary artery disease.

[Source ²² ]

Pericarditis can be excluded by review of an electrocardiogram and, if required, echocardiogram findings. Pneumonia and pneumothorax can be evaluated with chest radiography ¹. Aortic dissection can be excluded with chest radiography in very low-risk patients; otherwise, computed tomography angiography should be performed ²³.

Viruses are common causative agents of pleuritic chest pain. Coxsackieviruses, respiratory syncytial virus, influenza, parainfluenza, mumps, adenovirus, cytomegalovirus, and Epstein-Barr virus are likely pathogens ²⁴.

Initial evaluation of rib cage pain

Algorithmic approaches to the diagnosis and workup of the patient presenting with chest pain in the office setting have not been specifically studied. Differentiating ischemic from nonischemic causes often is difficult, and patients with chest pain with an ischemic etiology often appear well. As such, the initial diagnostic approach should always consider a cardiac cause for the chest pain, unless other causes are apparent ²⁵.

The first decision point for most physicians is whether or not the chest pain is caused by coronary ischemia ²⁵. Acute coronary syndrome is a constellation of clinical findings that suggests acute myocardial ischemia encompassing unstable angina and acute heart attack. Angina has been described as deep, poorly localized chest or arm discomfort (pain or pressure) that is reproducibly associated with physical exertion or emotional stress and is relieved promptly with rest or sublingual nitroglycerin ²⁶. Unstable angina is defined as angina at rest, new-onset angina, or angina that has become more severe or longer in duration ²⁷. Acute heart attack is defined as ST segment changes (elevation or depression) on electrocardiography (ECG) and positive laboratory markers of myocardial necrosis (e.g., troponin I) ²⁶. In office and ambulatory settings, the clinical impression is, in most cases, shaped by the presenting symptoms, physical examination, and initial ECG, combined with the patient’s risk of acute coronary syndrome ²⁸.

The initial goal is to determine if the patient needs to be referred for further testing (e.g., troponin I or stress testing, coronary angiography) to rule in or out a potentially catastrophic acute coronary syndrome and acute heart attack. One recent meta-analysis concluded that the history and physical examination were mostly not helpful in diagnosing acute coronary syndrome or acute heart attack in patients presenting with chest pain, especially in a low prevalence setting ²⁹.

Although individual characteristics may not rule in or out a diagnosis, a combination of signs and symptoms may increase diagnostic accuracy ³⁰. Characteristics traditionally associated with increased likelihood of acute heart attack include male sex plus age older than 60 years; diaphoresis; pain that radiates to the shoulder, neck, arm, or jaw; and a history of angina or acute heart attack ³¹. Predictability may be influenced by patient description of their symptoms. Patients often do not use the term pain to describe their symptoms, but frequently use other terms like discomfort, tightness, squeezing, or indigestion ²⁵.

Other clinical features that increase the likelihood of heart attack in patients with acute chest pain include pain that radiates to both arms (positive likelihood ratio [LR+] = 7.1), a third heart sound on auscultation (LR+ = 3.2), and hypotension (LR+ = 3.1). Clinical features that decrease the likelihood of acute heart attack include pleuritic chest pain (negative likelihood ratio [LR–] = 0.2), sharp or stabbing chest pain (LR– = 0.3), and chest pain reproduced by palpation (LR– = 0.2 to 0.4) ¹¹.

The presence or absence of comorbidities, such as diabetes mellitus, tobacco use, hyperlipidemia, or hypertension, as cardiac risk factors weakly predict acute coronary syndrome in patients older than 40 years (LR+ = 2.1 in persons 40 to 65 years of age; LR+ = 1.1 in patients older than 65 years) ³²; however, evaluating for presence or absence of comorbidities is still an important component of the initial assessment.

One recently developed and validated clinical decision rule (Table 4) outlines five items that best predict coronary artery disease as the cause of chest pain: age/sex (55 years or older in men or 65 years or older in women); known coronary artery disease, occlusive vascular disease, or cerebrovascular disease; pain that is worse during exercise; pain not reproducible by palpation; and patient assumption that the pain is of cardiac origin ³³.

Table 4. Clinical Decision Rule for Identifying Patients with Chest Pain Caused by Coronary Artery Disease

Variable	Points
Age 55 years or older in men; 65 years or older in women	1
Known CAD or cerebrovascular disease	1
Pain not reproducible by palpation	1
Pain worse during exercise	1
Patient assumes pain is cardiogenic	1
Total points:	______

Points	Patients with CAD	Patients without CAD	Likelihood ratio	Predictive value (%)
0 or 1	3	542	0.0	0.6
2 or 3	91	659	0.9	12.1
4 or 5	94	56	11.2	62.7

CAD = coronary artery disease.

[Source ⁹ ]

Among those with none or one of these clinical factors, only 1 percent had coronary artery disease, whereas 63 percent of the patients with four or five of the factors had coronary artery disease. The study results suggest that patients with chest pain and four or five of these factors require urgent workup. Physicians should consider applying a validated clinical decision rule to predict heart disease as a cause of chest pain ³³

Twelve-lead ECG is typically the test of choice in the initial evaluation of patients with chest pain ²⁸. ST segment changes (elevation or depression), new-onset left bundle branch block, presence of Q waves, and new-onset T wave inversion increase the likelihood of acute coronary syndrome or acute heart attack ³⁴. Concern based on the clinical impression (history, physical examination, risk factors, and 12-lead ECG) often will influence the physician’s decision regarding whether to refer the patient to a higher level of care (emergency department or hospital) for further workup and treatment, or to look for other possible diagnoses for the chest pain ²⁵.

Other causes of rib cage pain

If the initial evaluation indicates that a cardiac cause of acute coronary syndrome is less likely, other noncardiac causes of chest pain should be considered. Understanding that there are common conditions that often occur, with the clinical impression, will help lead to a correct diagnosis.

Chest wall pain

One prospective cohort study identified four clinical factors that predict a final diagnosis of chest wall pain in patients presenting to the primary care office with chest pain: localized muscle tension, stinging pain, pain reproducible by palpation, and the absence of a cough. Having at least two of these findings had a 77 percent positive predictive value for chest wall pain, and having none or one had an 82 percent negative predictive value ¹⁴.

Costochondritis

Often considered a subset of chest wall pain, costochondritis is a self-limited condition characterized by pain reproducible by palpation in the parasternal/costochondral joints. It is sometimes called Tietze syndrome, which is distinguished from costochondritis by the presence of swelling over the affected joints ³⁵. Costochondritis is a clinical diagnosis and does not require specific diagnostic testing in the absence of concomitant cardiopulmonary symptoms or risk factors ³⁶.

Gastroesophageal reflux disease (GERD)

Classic symptoms of gastroesophageal reflux disease (GERD) include a burning retrosternal pain, acid regurgitation, and a sour or bitter taste in the mouth ³⁷. No useful physical examination maneuvers exist to assist in establishing the diagnosis, and there is no standard test to rule it in or out. However, a one-week trial of a high-dose proton pump inhibitor is modestly sensitive and specific for GERD, with modest LRs (LR+ = 3.1; LR– = 0.3) ¹⁵.

Panic disorder and anxiety state

Panic disorder and anxiety state are common. One in four persons with a panic attack will have chest pain and shortness of breath ³⁸. Yet, concomitant panic disorder and chest pain are often not recognized, leading to more testing, follow-up, and higher costs of care ³⁹. Panic may cause chest pain and vice versa ³⁸. Several validated brief questionnaires are used to diagnose panic disorder and anxiety state. One question (In the past four weeks, have you had an anxiety attack [suddenly feeling fear or panic]?) is sensitive (93 percent) and modestly specific (78 percent) in detecting panic disorder (LR+ = 4.2; LR– = 0.09) ¹⁶.

Less common causes, but important, diagnostic considerations

Pericarditis

Pericarditis is the clinical triad of pleuritic chest pain, pericardial friction rub, and diffuse electrocardiographic ST-T wave changes ⁴⁰. ECG usually demonstrates diffuse ST segment elevation and PR interval depression without T wave inversion. Acute pericarditis should be considered in patients presenting with new-onset chest pain that increases with inspiration or when reclining, and is lessened by leaning forward ⁴¹.

Pneumonia

Community-acquired pneumonia is a cause of chest pain and respiratory symptoms in the outpatient setting. Common symptoms include fever, chills, productive cough, and pleuritic chest pain ⁴². Fever, egophony heard during auscultation of the lungs, and dullness to percussion of the posterior thorax are suggestive of pneumonia.10 Clinical impression is modestly useful for ruling in or out pneumonia (LR+ = 2.0; LR– = 0.24) ⁴³. The test of choice for diagnosing pneumonia is chest radiography ¹, although it has been more recently recommended that it be performed only if other diagnoses are being considered in the uncomplicated outpatient setting ⁴⁴.

Heart failure

Most patients with heart failure present with dyspnea on exertion, although some will have chest pain ⁴⁵. A history of heart failure or acute heart attack best predicts the presence of heart failure (LR+ = 5.8 and 3.1, respectively) ⁴⁵. Clinical impression/judgment is predictive of heart failure (LR+ = 9.9; LR– = 0.65), as is pulmonary edema on chest radiography (LR+ = 11.0) ⁴⁵.

Pulmonary embolism

Diagnosing pulmonary embolism in the office based on signs and symptoms is difficult because of its highly variable presentation. Although dyspnea, tachycardia, and/or chest pain are present in 97 percent of those diagnosed with pulmonary embolism ⁴⁶, there is no single clinical feature that effectively rules it in or out ⁴⁷. The physician can estimate the patient’s likelihood of pulmonary embolism by using a validated clinical decision rule, such as the Wells criteria (Table 5), to determine if further testing should be performed (e.g., d-dimer assay, ventilation-perfusion scan, helical computed tomography of the pulmonary arteries) ¹⁷.

Table 5. Wells Clinical Prediction Rule for pulmonary embolism

Component	Points
Clinical signs of DVT (asymmetric leg swelling, palpable calf pain)	3
Diagnosis of PE is more likely than an alternative diagnosis	3
Heart rate greater than 100 beats per minute	1.5
Previous diagnosis of DVT or PE	1.5
Bed rest immobilization or surgery within the past four weeks	1.5
Hemoptysis	1
Malignancy within the past six months	1

Points	Risk of PE	Probability of PE (%)
0 to 1 point	Low	1.3
2 to 6 points	Moderate	16
Greater than 6 points	High	41

Footnote: DVT = deep venous thrombosis; PE = pulmonary embolism.

[Source ⁹ ]

Acute thoracic aortic dissection

Patients with acute thoracic aortic dissection may present with chest or back pain ⁴⁸. History and physical examination are only modestly useful for ruling in or out the condition; acute chest or back pain and a pulse differential in the upper extremities modestly increase the likelihood of an acute thoracic aortic dissection (LR+ = 5.3) ¹³.

Rib cage pain treatment

After excluding the serious causes of rib cage pain that require emergent evaluation, there are two primary management considerations: controlling the pain and treating the cause of the underlying condition. Initial pain control is best achieved with nonsteroidal anti-inflammatory drugs (NSAIDs) ⁴⁹.

Once pain is adequately controlled and serious underlying conditions are excluded, other conditions should be treated. Antimicrobial or antiparasitic agents should be started based on the presumed organism in pneumonia. Colchicine (1.2 to 2.0 mg orally once per day or divided twice per day) is the standard treatment for familial Mediterranean fever ⁵⁰. Biologic agents such as anti-interleukin-1, interleukin-6 inhibitor, and tocilizumab may have utility in refractory cases of familial Mediterranean fever ⁵¹.

In patients diagnosed with pneumonia who smoke tobacco, have persistent symptoms, or are older than 50 years, it is important to document resolution of the abnormality with repeat chest radiography performed six weeks after initial treatment ⁵². These patients are at increased risk of developing pneumonia secondary to an obstructing lesion such as lung cancer. One study showed that of 236 adults presenting to their primary care physician with community-acquired pneumonia, 10 were found to have an underlying lung cancer ⁵². The percentage of those with lung cancer rose to 17% in smokers older than 60 years ⁵². Studies have shown resolution of radiographic abnormalities in 60% to 73% of patients by six weeks after diagnosis ⁵². Further evaluation should be considered in patients with persisting symptoms or radiographic abnormalities.

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