What is the appropriate evaluation and management for a patient presenting with 4 days of right-sided pain under the rib cage?

Right Upper Quadrant Pain Under Rib Cage: Evaluation and Management

Start with a focused clinical assessment to differentiate between biliary/hepatic pathology, musculoskeletal causes, and other serious conditions, followed by appropriate imaging based on clinical suspicion.

Initial Clinical Assessment

Key Historical Features to Elicit

• Pain characteristics suggesting serious pathology: Pain that interrupts normal activity, accompanied by cold sweat, nausea, vomiting, or fever 1, 2
• Pain characteristics suggesting musculoskeletal origin: Pain that varies with respiration, body position, is well-localized on the chest wall, reproducible with palpation, or affected by breathing, turning, twisting, or bending 1, 2
• Biliary colic indicators: Postprandial pain (especially after fatty meals), radiation to right shoulder or back, episodic nature 1
• Duration and progression: 4 days suggests subacute process rather than acute emergency, but persistent symptoms warrant investigation 3

Physical Examination Priorities

• Systematic palpation of the costal margin: Press firmly along the right costal margin to identify focal tenderness and reproduce the pain - this is diagnostic for painful rib syndrome if positive 3
• Murphy's sign: Assess for gallbladder tenderness during deep inspiration 1
• Chest wall tenderness: Palpate intercostal spaces and costochondral junctions to identify musculoskeletal sources 2, 3
• Vital signs: Fever and tachycardia suggest infectious or inflammatory process 1

Diagnostic Imaging Algorithm

First-Line Imaging

Right upper quadrant ultrasound is the appropriate initial imaging study if biliary pathology is suspected based on clinical features (postprandial pain, right upper quadrant tenderness). 1

Chest radiography (PA and lateral) should be obtained first if the pain is primarily along the rib cage or chest wall, to rule out pneumothorax, rib fracture, or pulmonary pathology. 1, 2

When to Escalate Imaging

• CT abdomen and pelvis with IV contrast: If ultrasound is nondiagnostic or if clinical suspicion remains high for hepatobiliary pathology, pancreatitis, or other intra-abdominal processes 1
• Dedicated rib series radiographs: If chest X-ray is normal but focal rib pain persists on examination, though sensitivity is limited (fractures detected in <5% of stable outpatients) 1, 2
• Point-of-care ultrasound: Can detect costochondral abnormalities with high accuracy (89% sensitivity for slipping rib syndrome) if musculoskeletal cause is suspected 2, 4

Common Diagnoses in This Presentation

Painful Rib Syndrome (Costal Margin Syndrome)

• Accounts for 3% of general medical referrals and is characterized by: pain in lower chest/upper abdomen, tender spot on costal margin, and reproduction of pain with pressure 3
• This is a clinical diagnosis requiring no investigation - systematic firm palpation of the costal margin is diagnostic 3
• 70% of patients continue to have pain at 4-year follow-up, though most learn to live with it 3

Slipping Rib Syndrome

• Caused by hypermobility of ribs 8-10, where cartilaginous rib tips slip under the rib above, impinging the intercostal nerve 4
• Dynamic ultrasound confirms diagnosis with 89% sensitivity and 100% specificity 2, 4
• Patients typically report months to years of symptoms before diagnosis 4

Biliary Pathology

• Ultrasound has high sensitivity for gallstones and cholecystitis and should be first-line if postprandial pain or Murphy's sign present 1

Management Approach

For Musculoskeletal/Rib Pain

• Regular acetaminophen every 6 hours as first-line treatment 2, 5
• NSAIDs for severe pain, considering potential adverse events particularly in elderly patients 2, 5
• Reassurance and firm diagnosis - even when painful rib syndrome is diagnosed, 33% of patients are re-referred by their GP, highlighting the importance of clear communication 3

Red Flags Requiring Urgent Evaluation

• Fever with leukocytosis: Suggests infectious process requiring CT imaging 1
• Hemodynamic instability or severe systemic symptoms: Requires immediate hospital evaluation 1
• Cardiac risk factors with chest pain: ECG mandatory to rule out cardiac ischemia, even in younger patients 1

Critical Pitfalls to Avoid

• Do not order extensive investigations for painful rib syndrome - it is a safe clinical diagnosis based on reproducible tenderness at the costal margin 3
• Do not assume musculoskeletal origin without palpating the exact site of pain - 70% of patients with painful rib syndrome are women with mean age 48 years, and many undergo unnecessary procedures including cholecystectomy 3
• Standard chest radiographs miss up to 50% of rib fractures - if clinical suspicion is high, consider dedicated rib views or ultrasound 2, 5
• Do not dismiss persistent symptoms - slipping rib syndrome patients report months to years of typical pain before diagnosis due to underrecognition 4