Diagnostic Approach to Dull Pain from Lower Rib/Costal Margin to Loin

Clinical Assessment and Diagnosis

The American College of Cardiology states that cardiac causes of chest pain are extremely unlikely in a 21-year-old without exertional component, dyspnea, or radiation to arm/jaw 3, 4
Systematic palpation of the costal margin can diagnose painful rib syndrome, with pain reproduction being a key diagnostic feature 1, 2
Dynamic ultrasound can detect slipping rib syndrome with 89% sensitivity and 100% specificity 1
The American Heart Association, as published in Circulation, notes that pulmonary embolism/pneumothorax would present with dyspnea, sudden onset, or respiratory distress 5, 2

The diagnostic algorithm involves a physical examination, including firm systematic palpation of the entire costal margin bilaterally, to assess for reproducible tenderness and rib mobility 1, 2, 4
If the physical exam is positive for musculoskeletal pain, no imaging is required, and treatment can proceed directly 1
First-line treatment includes regular acetaminophen as primary analgesic, with NSAIDs as second-line for severe pain 1, 2, 4
Avoiding movements or postures that worsen pain and providing reassurance that the condition is benign and self-limited are also recommended 2, 4