Scalene Muscles Relations Mnemonic
Remembers the anatomical relationship between scalene muscles and subclavian vessels/brachial plexus. Critical for understanding thoracic outlet syndrome and central line placement.
The Mnemonic
"The Subclavian Vein is ANTErior to the ANTErior scalene"
Breakdown
Vein anterior
Subclavian vein passes ANTERIOR to anterior scalene
Artery between
Subclavian artery passes BETWEEN anterior and middle scalene
Plexus between
Brachial plexus passes BETWEEN anterior and middle scalene
Clinical Relevance
Thoracic outlet syndrome occurs from compression of neurovascular structures by scalenes or cervical rib. Anterior scalene blocks guide for brachial plexus anesthesia target this space.
Study Tips
- ✓VAN = Vein, Artery, Nerves from anterior to posterior
- ✓Interscalene triangle: anterior scalene, middle scalene, first rib
- ✓Phrenic nerve runs ON anterior scalene (C3-4-5 keeps diaphragm alive)
- ✓Subclavian vein is used for central lines - anterior to scalene
FAQs
Common questions about this mnemonic
TOS is compression of neurovascular structures (brachial plexus, subclavian artery/vein) as they exit the thorax. Causes include cervical rib, scalene hypertrophy, or poor posture. Symptoms include arm pain, numbness, weakness, and vascular changes.
The brachial plexus passes between the anterior and middle scalene muscles. Interscalene nerve blocks inject local anesthetic here to anesthetize the shoulder and upper arm for surgery or pain management.