Patient Positioning
Patient seated in front of the examiner, hand palm up resting on the examination table.
Probe Positioning
Place the transducer on transverse plane over the palmar wrist. First move the transducer cranially to identify the bony landmarks of the proximal carpal tunnel: radial sided the scaphoid tubercle, ulnarly the pisiform. To identify the distal carpal tunnel, muve the transducer distally over the radial sided trapezium tubercle and the hamate hook ulnarly.
ma: median artery
mn: median nerv
ua: ulnar artery
fcr: flexor carpi radialis tendon
The persistent median artery of the forearm is an accessory artery which arises from the ulnar artery that usually regresses by eight weeks gestation. It is present in ~10% (2.2-23%) of the population.