A 9-year-old girl is found to have hypertension limited to the upper limbs, radio-femoral delay, and a soft systolic murmur over the interscapular area. Chest radiograph shows notching of the inferior borders of the third to eighth posterior ribs. The rib notching results from:

• A Erosion by enlarged bronchial arteries
• B Erosion by dilated internal mammary arteries
• C Osteopenia secondary to chronic hypoxia
• D Pressure from dilated posterior intercostal collateral arteries ✓

Explanation

In coarctation of the aorta, blood reaches the lower body through collaterals from the subclavian arteries via the internal mammary, scapular, and posterior intercostal arteries. Enlarged tortuous intercostal arteries running along the inferior rib margins produce erosive notching of the third to eighth posterior ribs on chest radiograph. Bronchial arteries are not part of this collateral pathway, and internal mammary dilation does not erode ribs.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.