Palmar branch of the median nerve
Encyclopedia
The palmar branch of the median nerve is a branch of the median nerve
which arises at the lower part of the forearm
.
, and divides into a lateral and a medial branch;
. Therefore, this portion of the median nerve usually remains functioning during carpal tunnel syndrome
.
Median nerve
The median nerve is a nerve in humans and other animals. It is in the upper limb. It is one of the five main nerves originating from the brachial plexus....
which arises at the lower part of the forearm
Forearm
-See also:*Forearm flexors*Forearm muscles...
.
Branches
It pierces the palmar carpal ligamentPalmar carpal ligament
The palmar carpal ligament is a term that is often used in anatomy to describe the thickened portion of antebrachial fascia on the anterior of the wrist. It is officially unnamed....
, and divides into a lateral and a medial branch;
- The lateral branch supplies the skin over the ball of the thumbThumbThe thumb is the first digit of the hand. When a person is standing in the medical anatomical position , the thumb is the lateral-most digit...
, and communicates with the volar branch of the lateral antebrachial cutaneous nerve. - The medial branch supplies the skin of the palmHandA hand is a prehensile, multi-fingered extremity located at the end of an arm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs...
and communicates with the palmar cutaneous branch of the ulnar.
Clinical significance
Unlike most of the median nerve innervation of the hand, the palmar branch travels superficial to the Flexor retinaculum of the handFlexor retinaculum of the hand
The flexor retinaculum is a strong, fibrous band that arches over the carpus, converting the deep groove on the front of the carpal bones into a tunnel, the carpal tunnel, through which the Flexor tendons of the digits and the median nerve pass.It is attached, medially, to the pisiform and the...
. Therefore, this portion of the median nerve usually remains functioning during carpal tunnel syndrome
Carpal tunnel syndrome
Carpal Tunnel Syndrome is an entrapment idiopathic median neuropathy, causing paresthesia, pain, and other symptoms in the distribution of the median nerve due to its compression at the wrist in the carpal tunnel. The pathophysiology is not completely understood but can be considered compression...
.