American Board of Surgery Qualifying Exam (ABS QE) Practice Test

In the case of a distal, supracondylar humerus fracture, which artery is at risk?

1. Radial artery

2. Brachial artery

3. Axillary artery

4. Subclavian artery

The correct answer is: Brachial artery

In a distal supracondylar humerus fracture, the brachial artery is at significant risk due to its anatomical position. The brachial artery runs along the medial aspect of the humerus and is particularly vulnerable to injury from fragments of bone or from the severe trauma associated with such fractures. When a supracondylar fracture occurs, especially if it is displaced, the sharp bony fragments can impinge on the artery, potentially leading to vascular compromise. This risk is heightened in pediatric populations, where these fractures are more common, as the associated swelling and hematoma can further threaten vascular integrity. While the radial artery does run close to the elbow, it is less likely to be significantly affected in this specific fracture type compared to the brachial artery. The axillary artery is located more proximally, making it less relevant in the context of distal humeral fractures. The subclavian artery, located even further from the injury site, is not associated with the risks stemming from distal supracondylar humerus fractures. Thus, understanding the anatomy and relationships of these arteries to the humerus helps clarify why the brachial artery is the one at risk in these scenarios.