Anatomy Guide › Upper limb
Brachial Artery
Every time a cuff inflates around your upper arm, it is aimed at one vessel: the brachial artery. This is the arm's main arterial trunk, the continuation of the axillary artery from the armpit. It runs down the inner side of the upper arm alongside the humerus, then crosses the front of the elbow crease before splitting into the radial and ulnar arteries that supply the forearm and hand.
The blood pressure ritual works because of the artery's convenient anatomy. At the elbow crease it lies close to the surface, just under the skin and a thin fibrous sheet, where a stethoscope can hear flow returning as cuff pressure releases — the tapping Korotkoff sounds that mark systolic and diastolic pressure. The standard advice to measure BP 'at heart level' exists because the brachial artery's height relative to the heart changes the reading.
Along its course the brachial artery feeds the arm's flexor muscles and sends a deep branch spiraling behind the humerus with the radial nerve. It also builds a safety net around the elbow: several small branches join with forearm vessels above and below the joint, so blood can detour if the main channel is briefly compressed — useful for a joint that bends hundreds of times a day. Still, a badly displaced elbow fracture in a child can kink the artery, one of the true urgencies of pediatric orthopedics.
In Anamo, the brachial artery is the connecting corridor between shoulder vessels and forearm vessels. If axillary guesses run warm and radial guesses warmer, the brachial is the segment in between — vascular rounds often resolve exactly this way, one segment at a time.
- The artery compressed by blood pressure cuffs
- Continues the axillary artery and splits into radial and ulnar arteries
- Its pulse is easily felt at the inner elbow crease
- Builds a collateral network so the elbow can bend without cutting flow
Think you could find the brachial artery on a 3D model? Play Anamo and test yourself — every guess is color-coded by how close it lands to the mystery structure.