Along the spoke (radius) it runs on the front of the forearm under the brachioradialis muscle. In its course it is accompanied by a superficial branch of the radial nerve. It is easy to palpate in the foveola radialis (Tabatière).
This is limited by the tendons of the Musculus extensor pollicis longus and the Musculus extensor pollicis brevis. In its course, the radial artery gives off the following branches:
- The Arteria recurrens radialis is a receding vessel and supplies the crook of the arm. – The ramus carpalis palmaris draws towards the vascular network of the carpal bones and the
- Ramus palmaris superficialis moves to the thumb.
- The ramus carpalis dorsale supplies the outer side of the hand. – Another branch supplies the thumb (Arteria princeps pollicis) and the index finger (Arteria radialis indices). On the hand it merges into the palmar arch (Arcus palmaris profundus), which is located at the base of the metacarpals and supplies the palm with oxygenated blood.
- Some smaller branches, the metacarpophalangeal artery palmares, run between the metacarpals and anastomose with the vascular branches of the superficial palmar arch. In the crook of the arm the brachial artery splits into two further arteries: The radial and ulnar. The radial artery runs over the pronator teres muscle and between the flexor carpi radialis and brachioradialis muscles.
The brachioradialis muscle is also the leading structure of the radial artery. It runs first under the belly of the muscle and later next to its tendon. The radial artery is accompanied by two veins, the Vv.
radiales, and also lymph vessels. In the area of the tabatière (wrist) the A. radialis passes through the heads of the M. interosseus dorsalis I and thus reaches the palm of the hand. Here it gives off several branches, such as the A. princeps pollicis (for the thumb).
The A. radialis then forms together with the A. ulnaris the Arcus palmaris profundus which supplies the palm. In front of the Retinaculum extensorum (on the back of the wrist) the Ramus carpalis dorsalis splits off, from which the Aa. metacarpales dorsales are formed.
These small arteries form the thin Aa. digitales dorsales and thus supply the back of the fingers. The radial artery has a diameter of approximately 2 to 3 mm.
The pulse of the radial artery can be easily felt and measured at the wrist, so that arterial blood is often taken for examination or an invasive blood pressure measurement can be applied. In dialysis patients, the radial artery is also usually used to create a cimino shunt.
Pulse palpation at the radial artery
In medicine, the radial artery is a preferred place to feel the pulse. The radial pulse is most easily found on the underside of the forearm, near the wrist. The radial artery runs along the forearm on the side of the os radius (spoke), i.e. on the same side as the thumb.
The artery runs near the tendon of the flexor carpi radialis and palmaris longus tendons. When the wrist is flexed, the tendons of both muscles become particularly prominent. In order to be able to feel the pulse, the fingers (preferably the index finger and middle finger, but never the thumb) must be placed on the side of the thumb directly next to the above-mentioned tendons, approximately one or two transverse fingers below the ball of the thumb.
At the fingertip you can then feel the pulse and count. If the pulse disappears, you should reduce the pressure a little or put your fingers a little higher or lower. Another place where you can feel the radial pulse is the tabatière.
The tabatière is located on the thumb side of the forearm below the thumb. This hollow can be found especially well when the thumb is spread apart. Analogous to the pulse measurement on the bottom of the arm, you simply have to press your fingers slightly in this depression and then measure the pulse.