Arterial thoracic outlet syndrome due to a first-rib anomaly causing brachial artery embolic occlusion: a case report

TL;DR

A rare case of arterial thoracic outlet syndrome caused by a first-rib anomaly led to brachial artery occlusion and was diagnosed using 3D imaging.

Contribution

Demonstrates the importance of 3D imaging in diagnosing complex thoracic outlet anomalies.

Findings

3D imaging identified focal arterial compression due to rib fusion, confirming the diagnosis.

Routine 2D imaging may delay diagnosis in complex thoracic outlet cases.

Bilateral first-rib anomalies were present, but only the right side caused arterial compression.

Abstract

Arterial thoracic outlet syndrome is a rare condition caused by compression of the subclavian artery at the thoracic outlet, which often leads to delayed diagnosis and potentially severe outcomes such as upper limb necrosis. We report a case of a man in his 20s who presented with coldness in the right fingers, exacerbated by cold environments. Chest radiography revealed abnormal bone structures, and contrast-enhanced computed tomography confirmed stenosis and post-stenotic dilation of the right subclavian artery, thrombus formation, and occlusion of the brachial artery. Although bilateral first-rib anomalies were present, three-dimensional volume-rendered imaging identified focal arterial compression on the right side due to abnormal fusion of the first and second ribs, leading to a definitive diagnosis of arterial thoracic outlet syndrome. This case highlights that reliance on routine two-dimensional imaging alone may contribute to diagnostic delay, whereas selective use of three-dimensional reconstruction can provide critical anatomical insight, enabling accurate diagnosis and appropriate management in patients with complex thoracic outlet anatomy.

Figures