How should differential rib pain be evaluated and managed in a patient?

Differential Diagnosis and Management of Rib Pain

Begin with systematic palpation of the entire costal margin to reproduce pain, as this clinical maneuver alone can diagnose the most common causes of rib pain without requiring imaging in the majority of cases. 1, 2

Initial Clinical Assessment

Red Flag Symptoms Requiring Urgent Evaluation

• Symptoms interrupting normal activity accompanied by cold sweats, nausea, vomiting, fainting, or severe anxiety 1
• Sudden onset with dyspnea or respiratory distress (suggests pneumothorax or pulmonary embolism) 3, 2
• Known malignancy or constitutional symptoms (weight loss, night sweats, fever) 1
• Recent trauma with multiple rib involvement or flail chest 3

Reassuring Clinical Features

• Pain that varies with respiration, body position, or food intake 1
• Well-localized chest wall pain with reproducible tenderness on palpation 1, 2
• Pain affected by breathing, turning, twisting, or bending 1
• Pain generated from multiple sites on examination 1

Diagnostic Algorithm

Step 1: Physical Examination

Perform firm systematic palpation of the entire costal margin bilaterally to identify:

• Reproducible tenderness at specific points 2, 4
• Rib mobility or subluxation (slipping rib syndrome) 1, 2
• Trigger points consistent with musculoskeletal pain 5, 4

If physical exam reproduces the exact pain, no imaging is required and you can proceed directly to treatment. 2, 4

Step 2: Initial Imaging (When Indicated)

Chest radiography is the recommended first-line imaging test when:

• Physical examination is non-diagnostic 1, 3
• Need to exclude fracture, infection, neoplasm, or pneumothorax 1
• Trauma history is present 3

Important caveat: Standard chest radiographs miss up to 50% of rib fractures and up to 90% of costochondral junction injuries. 1, 3

Step 3: Advanced Imaging (Selective Use)

• Dedicated rib series radiographs: For focal chest wall pain when fracture is suspected but chest X-ray is negative 1
• Point-of-care ultrasound: Detects 29% of rib fractures missed on chest radiography; preferred for costochondral junction evaluation with high sensitivity 1, 3
• Dynamic ultrasound: For suspected slipping rib syndrome (89% sensitivity, 100% specificity) 1, 2
• CT chest: Reserved for suspected malignancy, evaluation of pulmonary disease, or when multiple injuries are suspected 1, 3

Common Differential Diagnoses

Musculoskeletal Causes (Most Common)

• Painful rib syndrome: Accounts for 3% of general medical referrals; diagnosed by reproducible pain on costal margin palpation 4
• Rib fractures: Most common in ribs 3-8 and lateral regions; cough-induced fractures occur in 82.4% of patients with post-tussive chest pain 1, 3
• Costochondritis: Inflammation of costochondral cartilage 3
• Slipping rib syndrome: Rib subluxation from joint connections 1, 3
• Intercostal muscle strain or myofascial injury 3, 5

Pulmonary Causes

• Pleurisy, pneumothorax, pulmonary embolism, pneumonia 3

Gastrointestinal Causes

• GERD and esophageal disorders account for 10-20% of chest pain in outpatients 3

Serious Causes Requiring Exclusion

• Skeletal tuberculosis: Consider in patients from endemic areas with persistent pain despite treatment 6
• Malignancy: Primary chest wall neoplasms or metastases 1

Management Approach

For Musculoskeletal/Benign Rib Pain

First-line treatment:

• Regular acetaminophen as primary analgesic 1, 2
• Explanation of the benign nature and reassurance that pain is real and manageable 5, 4
• Avoidance of movements or postures that worsen pain 2

Second-line treatment for severe pain:

• NSAIDs considering potential adverse events 1, 2
• Low-dose ketamine (0.3 mg/kg over 15 minutes) as alternative to opioids 1

Non-pharmacological measures:

• Immobilization, cold compresses in conjunction with pharmacological therapy 1

For Rib Fractures

Pain control is essential to prevent respiratory complications including atelectasis and pneumonia, as each rib fracture increases pneumonia risk by 27% and mortality by 19% in elderly patients. 7

Surgical considerations:

• Flail chest or unstable chest wall requires surgical fixation 1
• Severe refractory pain or chest wall deformity may warrant surgical intervention 1
• Multiple fractures in elderly or those with pre-existing pulmonary disease require close monitoring 3

Critical Pitfalls to Avoid

• Do not rely solely on chest radiographs as they miss up to 50% of rib fractures and 90% of costochondral injuries 1, 3
• Do not over-investigate patients with reproducible pain on palpation - this is a safe clinical diagnosis requiring no investigation 4
• Do not underestimate pain control importance as inadequate analgesia leads to splinting, atelectasis, and pneumonia 7
• Do not dismiss persistent pain - reconsider diagnosis if pain fails to improve, particularly considering tuberculosis in patients from endemic areas 6
• Place radio-opaque skin markers on the site of pain to assist radiologists in localizing abnormalities when imaging is performed 1

Expected Course

Rib fractures typically heal within 6-8 weeks, though complete recovery may take up to 2 years in patients with multiple or displaced fractures. 1 For painful rib syndrome, 70% of patients still have pain at 4-year follow-up, though most learn to live with it. 4