The subclavian artery is the main arterial supply to the upper limb, neck, and cerebellum, passing between the anterior and middle scalene muscles in the scalene triangle before crossing the first rib to become the axillary artery. The scalene triangle between the scalenes and the first rib is the anatomical basis of vascular thoracic outlet syndrome from subclavian artery compression. Subclavian steal syndrome occurs when subclavian stenosis proximal to the vertebral origin reverses vertebral artery flow to supply the arm.
| Origin | Right: brachiocephalic trunk. Left: directly from the aortic arch |
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Thoracic outlet syndrome involving the subclavian artery produces a cervical rib pulsatile mass, arm claudication, Raynaud phenomenon, and distal embolisation from post-stenotic aneurysm thrombus. Subclavian artery injury from clavicle fractures or first rib resection is a rare but limb-threatening complication. Subclavian vein access for central line placement carries risk of subclavian artery puncture and pneumothorax.
Subclavian artery compression by cervical rib or scalene muscles producing post-stenotic aneurysm, distal embolisation, and arm claudication requiring first rib resection and arterial reconstruction.
Retrograde vertebral artery flow from proximal subclavian stenosis producing vertebrobasilar insufficiency on arm exercise, managed with subclavian angioplasty or bypass.
