Superficial branch of radial nerve

Superficial tree of the radial nerve
Diagram of segmental distribution of the cutaneous nerves of the right upper extremity. Radial superficial is labeled at right.
Nerves of the left upper extremity.
Details
From	Radial nerve
Identifiers
Latin	ramus superficialis nervi radialis
TA98	A14.2.03.056
TA2	6438
FMA	292885
Anatomical terms of neuroanatomy

The superficial branch of the radial nerve passes along the front of the radial side of the forearm to the commencement of its lower third. It is a sensory nerve.

It lies at first slightly lateral to the radial artery, concealed beneath the brachioradialis. In the middle third of the forearm, it lies behind the same muscle, close to the lateral side of the artery.

It quits the artery about 7 cm. above the wrist, passes beneath the tendon of the Brachioradialis, and, piercing the deep fascia, divides into two branches: lateral and medial.

Structure

Lateral branch

The lateral branch, the smaller, supplies the radial side of the thumb (by a digital nerve), the skin of the radial side and ball of the thumb, joining with the volar branch of the lateral antebrachial cutaneous nerve.

Medial branch

The medial branch communicates, above the wrist, with the dorsal branch of the lateral antebrachial cutaneous, and, on the back of the hand, with the dorsal branch of the ulnar nerve.

It then divides into four digital nerves, which are distributed as follows: the first supplies the ulnar side of the thumb; the second, the radial side of the index finger; the third, the adjoining sides of the index and middle fingers; the fourth communicates with a filament from the dorsal branch of the ulnar nerve, and supplies the adjacent sides of the middle and ring fingers.

Clinical significance

The superficial branch of radial nerve is associated with an entrapment neuropathy called Wartenberg's syndrome. The nerve may be compressed due to wearing a tight wristband, watch or bracelet.

Additional images

• 
  Ulnar and radial arteries. Deep view.
• 
  Superficial palmar nerves.
• 
  Deep palmar nerves.
• 
  Front of right upper extremity, showing surface markings for bones, arteries, and nerves.

References

This article incorporates text in the public domain from page 944 of the 20th edition of Gray's Anatomy (1918)

External links

• Hand kinesiology at the University of Kansas Medical Center
• lesson5nervesofhand at The Anatomy Lesson by Wesley Norman (Georgetown University)
• lesson5nervesofpostforearm at The Anatomy Lesson by Wesley Norman (Georgetown University)