Upper limb
Ulnar artery
Arteria ulnaris
- Origin
- Medial terminal branch of the brachial artery in the cubital fossa
- Insertion
- Descends along the ulnar side of the forearm, crosses Guyon's canal with the ulnar nerve, and forms the superficial palmar arch
- Function
- Primary arterial supply to the medial forearm flexors, hypothenar eminence, and digits via the superficial palmar arch
- Innervation
- Sympathetic vasomotor fibers distributed via the ulnar nerve
- Movement & chain
- Protected beneath flexor muscle bellies proximally, emerging superficially at the distal wrist
- Palpation
- Palpable at the anterior ulnar aspect of the wrist, lateral to the pisiform bone and flexor carpi ulnaris tendon
- Clinical
- Hypothenar hammer syndrome (ulnar artery thrombosis/aneurysm from repetitive blunt trauma); Guyon canal entrapment
- Segmental innervation
- C7–T1 segmental outflow
- In clinical practice
- Provides dominant flow to the superficial arch; assessed preoperatively via Allen's test before radial harvest
- Region in the model
- Upper limb