Cutaneous innervation of the upper limbs
Encyclopedia
Cutaneous innervation refers to the area of the skin
which is supplied by a specific nerve
.
Modern texts are in agreement about which areas of the skin are served by which nerves, but there are minor variations in some of the details. The borders designated by the diagrams in the 1918 edition of Gray's Anatomy
, provided below, are similar but not identical to those generally accepted today.
Skin
-Dermis:The dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis is tightly connected to the epidermis by a basement membrane. It also harbors many Mechanoreceptors that provide the sense of touch and heat...
which is supplied by a specific nerve
Nerve
A peripheral nerve, or simply nerve, is an enclosed, cable-like bundle of peripheral axons . A nerve provides a common pathway for the electrochemical nerve impulses that are transmitted along each of the axons. Nerves are found only in the peripheral nervous system...
.
Modern texts are in agreement about which areas of the skin are served by which nerves, but there are minor variations in some of the details. The borders designated by the diagrams in the 1918 edition of Gray's Anatomy
Gray's Anatomy
Gray's Anatomy is an English-language human anatomy textbook originally written by Henry Gray. The book is widely regarded as an extremely influential work on the subject, and has continued to be revised and republished from its initial publication in 1858 to the present day...
, provided below, are similar but not identical to those generally accepted today.
Arm and shoulder
- Supraclavicular nervesSupraclavicular nervesThe supraclavicular nerves arise from the third and fourth cervical nerves; they emerge beneath the posterior border of the Sternocleidomastoideus, and descend in the posterior triangle of the neck beneath the platysma and deep cervical fascia.-Branches:Near the clavicle they perforate the fascia...
(yellow) - Axillary nerveAxillary nerveThe axillary nerve or the circumflex nerve is a nerve of the human body, that comes off the of the brachial plexus at the level of the axilla and carries nerve fibers from C5 and C6...
(blue). Also Superior lateral cutaneous nerve of armSuperior lateral cutaneous nerve of armThe superior lateral cutaneous nerve of arm is the continuation of the posterior cord of the axillary nerve, after it pierces the deep fascia.-Course and targets:...
. - Inferior lateral cutaneous nerve of armInferior lateral cutaneous nerve of armThe inferior lateral cutaneous nerve of arm is a nerve found in humans and other animals. It is also called the inferior lateral brachial cutaneous nerve...
- Near blue "axillary" area, but actually branches from radial nerveRadial nerveThe radial nerve is a nerve in the human body that supplies the upper limb. It supplies the medial and lateral heads of the triceps brachii muscle of the arm, as well as all 12 muscles in the posterior osteofascial compartment of the forearm and the associated joints and overlying skin.It...
. Most modern sources distinguish the superior and inferior, but some still include a single "lateral brachial cutaneous nerve". ) - Intercostobrachial nerveIntercostobrachial nerve-Second intercostal nerve:The lateral cutaneous branch of the second intercostal nerve does not divide, like the others, into an anterior and a posterior branch; it is named the intercostobrachial nerve. It pierces the Intercostalis externus and the Serratus anterior, crosses the axilla to the...
(purple) - Medial cutaneous nerve of armMedial cutaneous nerve of armThe medial brachial cutaneous nerve is distributed to the skin on the medial brachial side of the arm.-Anatomy:...
(yellow) - labeled as "medial brachial cutaneous". - Posterior cutaneous nerve of armPosterior cutaneous nerve of armThe posterior cutaneous nerve of arm is a branch of the radial nerve that provides sensory innervation for much of the skin on the back of the arm...
(pink) - not explicitly distinguished from that of Posterior cutaneous nerve of forearmPosterior cutaneous nerve of forearmThe posterior cutaneous nerve of forearm is a nerve found in humans and other animals. It is also known as the dorsal antebrachial cutaneous nerve, the external cutaneous branch of the musculospiral nerve, and the posterior antebrachial cutaneous nerve...
on diagram, but is often distinguished in modern terminology
Forearm
- Lateral cutaneous nerve of forearmLateral cutaneous nerve of forearmThe lateral antebrachial cutaneous nerve passes behind the cephalic vein, and divides, opposite the elbow-joint, into a volar and a dorsal branch.-Volar branch:The volar branch descends along the radial border of the forearm to the...
(purple) - labeled as "lat. antibrach. cut.". Branch of musculocutaneous nerveMusculocutaneous nerveThe musculocutaneous nerve arises from the lateral cord of the brachial plexus, opposite the lower border of the Pectoralis major, its fibers being derived from C5, C6 and C7.-Path:...
. - Medial cutaneous nerve of forearmMedial cutaneous nerve of forearmThe Medial Antebrachial Cutaneous Nerve arises from the medial cord of the brachial plexus....
(green) - labeled as "medial antibrach. cutaneous". Branch of medial cordMedial cordThe Medial cord is a division of the brachial plexus.The medial cord gives rise to the following nerves:*The median pectoral nerve, C8 and T1, to the pectoralis muscle*The medial brachial cutaneous nerve, T1...
. - Posterior cutaneous nerve of forearmPosterior cutaneous nerve of forearmThe posterior cutaneous nerve of forearm is a nerve found in humans and other animals. It is also known as the dorsal antebrachial cutaneous nerve, the external cutaneous branch of the musculospiral nerve, and the posterior antebrachial cutaneous nerve...
(pink) - labeled as "dorsal antibrach. cut." Branch of radial nerveRadial nerveThe radial nerve is a nerve in the human body that supplies the upper limb. It supplies the medial and lateral heads of the triceps brachii muscle of the arm, as well as all 12 muscles in the posterior osteofascial compartment of the forearm and the associated joints and overlying skin.It...
.
Hand
- Superficial branch of the radial nerveSuperficial branch of the radial nerveThe 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 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...
(pink) - dorsal digital branch - Median nerveMedian nerveThe 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....
(yellow)- palmar digital branch - Superficial branch of ulnar nerveSuperficial branch of ulnar nerveThe superficial branch of the ulnar nerve is a terminal branch of the ulnar nerve. It supplies the palmaris brevis and the skin on the ulnar side of the hand, and divides into a proper palmar digital nerve and a common palmar digital nerve....
(blue) - palmar digital branch
External links
- Overview at luc.edu
- Overview at neuroguide.com - arms - arms