The recurrent branch of the median nerve is the branch of the

median nerve The median nerve is a nerve in humans and other animals in the upper limb. It is one of the five main nerves originating from the brachial plexus. The median nerve originates from the lateral and medial cords of the brachial plexus, and has contr ...

which supplies the

thenar muscles The thenar eminence is the mound formed at the base of the thumb on the palm of the hand by the muscles of the thumb#Intrinsic, intrinsic group of muscles of the thumb. The skin overlying this region is the area stimulated when trying to elicit ...

. It is also occasionally referred to as the thenar branch of the median nerve, or the thenar muscular branch of the median nerve.

Structure

An earlier branch of the median nerve also supplies the lumbricals 1 & 2. All other intrinsic muscles of the hand receive their motor innervation from branches of the

ulnar nerve In human anatomy, the ulnar nerve is a nerve that runs near the ulna bone. The ulnar collateral ligament of elbow joint is in relation with the ulnar nerve. The nerve is the largest in the human body unprotected by muscle or bone, so injury is ...

. It usually passes distal to the

transverse carpal ligament The flexor retinaculum (transverse carpal ligament, or anterior annular ligament) is a fibrous band on the palmar side of the hand near the wrist. It arches over the carpal bones of the hands, covering them and forming the carpal tunnel. Structur ...

. It ends in the

opponens pollicis The opponens pollicis is a small, triangular muscle in the hand, which functions to oppose the thumb. It is one of the three thenar muscles. It lies deep to the abductor pollicis brevis and lateral to the flexor pollicis brevis. Structure The opp ...

Function

In the

thenar eminence The thenar eminence is the mound formed at the base of the thumb on the palm of the hand by the intrinsic group of muscles of the thumb. The skin overlying this region is the area stimulated when trying to elicit a palmomental reflex. The word ...

, the recurrent branch of the median nerve provides motor innervation to: *

opponens pollicis muscle The opponens pollicis is a small, triangular muscle in the hand, which functions to oppose the thumb. It is one of the three thenar muscles. It lies deep to the abductor pollicis brevis and lateral to the flexor pollicis brevis. Structure The opp ...

. *

abductor pollicis brevis muscle The abductor pollicis brevis is a muscle in the hand that functions as an abductor of the thumb. Structure The abductor pollicis brevis is a flat, thin muscle located just under the skin. It is a thenar muscle, and therefore contributes to the ...

. * the superficial part of

flexor pollicis brevis muscle The flexor pollicis brevis is a muscle in the hand that flexes the thumb. It is one of three thenar muscles. It has both a superficial part and a deep part. Origin and insertion The muscle's superficial head arises from the distal edge of the fl ...

Clinical significance

The recurrent branch of the median nerve may be affected in

carpal tunnel syndrome Carpal tunnel syndrome (CTS) is the collection of symptoms and signs associated with median neuropathy at the carpal tunnel. Most CTS is related to idiopathic compression of the median nerve as it travels through the wrist at the carpal tunn ...

, or from its own separate

peripheral neuropathies Peripheral neuropathy, often shortened to neuropathy, is a general term describing disease affecting the peripheral nerves, meaning nerves beyond the brain and spinal cord. Damage to peripheral nerves may impair sensation, movement, gland, or or ...

Surgery

The recurrent branch of the median nerve is also

colloquially Colloquialism (), also called colloquial language, everyday language or general parlance, is the style (sociolinguistics), linguistic style used for casual (informal) communication. It is the most common functional style of speech, the idiom norm ...

called the "Million Dollar Nerve", because injury to this nerve during

carpal tunnel surgery Carpal tunnel surgery, also called carpal tunnel release (CTR) and carpal tunnel decompression surgery, is a surgery in which the transverse carpal ligament is divided. It is a surgical treatment for carpal tunnel syndrome (CTS) and recommended whe ...

can lead to a million dollar

lawsuit - A lawsuit is a proceeding by a party or parties against another in the civil court of law. The archaic term "suit in law" is found in only a small number of laws still in effect today. The term "lawsuit" is used in reference to a civil actio ...

. Injury to this nerve can lead to loss of function of the

thumb The thumb is the first digit of the hand, next to the index finger. When a person is standing in the medical anatomical position (where the palm is facing to the front), the thumb is the outermost digit. The Medical Latin English noun for thumb ...

. Such injury can happen if the flexor retinaculum is transected too radially. The possibility of injury to this nerve is even greater when it runs through the ligament without any curling at the distal part of the ligament.

References

External links

* {{Brachial plexus Nerves of the upper limb