Brachial Plexus Flashcards
What is the brachial plexus?
The brachial plexus is a network of nerve fibres that supplies the skin and musculature of the upper limb. It begins in the root of the neck, passes through the axilla, and enters the upper arm.
The plexus is formed by the anterior rami (divisions) of the cervical spinal nerves C5, C6, C7 and C8, and the first thoracic spinal nerve, T1.
What are the nerve roots of the musculocutaneous nerve?
C5 and C6
What are the motor functions of the muscolocutaneous nerve?
Innervates the muscles in the anterior compartment of the arm – the coracobrachialis, biceps brachii and the brachialis
What are the sensory functions of the musculocutaneous nerve?
Gives rise to the lateral cutaneous nerve of forearm, which innervates skin on the lateral surface of the forearm
What are the nerve roots of the axillary nerve?
C5-C6
What are the sensory functions of the axillary nerve?
Gives rise to superior lateral cutaneous nerve of arm, which innervates the skin over the lower deltoid ‘(‘regimental badge area’).
What are the motor functions of the axillary nerve?
(posterior terminal branch)Innervates the theres minor and (anterior terminal branch) deltoid muscle, abductors of the arm at the shoulder.
What are the nerve roots of the median nerve?
C5 – T1
What are the motor functions of the median nerve?
Innervates the flexor muscles in the anterior compartment of the forearm (except the flexor carpi ulnaris and part of the flexor digitorum profundus, innervated by the ulnar nerve). Also supplies innervation to the thenar muscles and lateral two lumbricals in the hand.
What are the sensory functions of the median nerve?
Gives rise to the palmar cutaneous branch, which innervates the lateral part of the palm, and the digital cutaneous branch, which innervates the lateral three and a half fingers on the anterior (palmar) surface of the hand.
What are the nerve roots of the radial nerve?
C5-T1
What are the motor functions of the radial nerve?
Innervates the triceps brachii, responsible for extension at the elbow. Innervates the majority of the extensor muscles in the forearm, responsible for extension of wrist and fingers and supination of the forearm
What are the sensory functions of the radial nerve?
Lower lateral cutaneous nerve of arminnervates the lateral aspect of the upper arm, below the deltoid muscle. Posterior cutaneous nerve of arm innervates the posterior surface of the upper arm. Posterior cutaneous nerve of forearm innervates a strip of skin down the middle of the posterior forearm. Superficial branch of the radial nerveinnervates the dorsal surface of the lateral three and half digits, and their associated palm area.
What are the nerve roots of the ulnar nerve?
C8-T1.
What are the motor functions of the ulnar nerve?
Innervates the muscles of the hand (apart from the thenar muscles and two lateral lumbricals), flexor carpi ulnaris and medial half of flexor digitorum profundus.
