Search results
Results From The WOW.Com Content Network
The C8 nerve contributes to the motor innervation of many of the muscles in the trunk and upper limb. Its primary function is the flexion of the fingers, and this is used as the clinical test for C8 integrity, in conjunction with the finger jerk reflex.
It innervates 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 originates from the brachial plexus, carrying fibers from the posterior roots of spinal nerves C5, C6, C7, C8 and T1. [1]
The muscle is inserted onto the radial sesamoid bone of the metacarpophalangeal joint. It acts to flex, adduct, and abduct the thumb, and is therefore also able to oppose the thumb. The superficial head is innervated by the median nerve, while the deep head is innervated by the ulnar nerve (C8-T1). [6]
The ulnar nerve originates from the C8-T1 nerve roots (and occasionally carries C7 fibers which arise from the lateral cord), [5] [6] which then form part of the medial cord of the brachial plexus, and descends medial to the brachial artery, up until the insertion point of coracobrachialis muscle (middle 5 cm over the medial border of the humerus).
The brachial plexus is a network of nerves (nerve plexus) formed by the anterior rami of the lower four cervical nerves and first thoracic nerve (C5, C6, C7, C8, and T1).This plexus extends from the spinal cord, through the cervicoaxillary canal in the neck, over the first rib, and into the armpit, it supplies afferent and efferent nerve fibers to the chest, shoulder, arm, forearm, and hand.
The medial pectoral nerve (also known as the medial anterior thoracic nerve) is (typically) a branch of the medial cord of the brachial plexus and is derived from spinal nerve roots C8-T1. It provides motor innervation to the pectoralis minor muscle, and the lower half (sternal part) of the pectoralis major muscle. It runs along the inferior ...
The nerve(s) which tell the muscle to act (innervates the muscle). The term "nerve" is included for clarity. Action The movement performed by the muscle from the standard anatomical position. In other positions, other actions may be performed. Antagonist The muscle which can 'cancel' or to some degree reverse the action of the muscle.
C6-C8: latissimus dorsi muscle axillary nerve: C5-C6: sensation to the shoulder and motor to the deltoid muscle and the teres minor: radial nerve: C5-C8, T1: triceps brachii muscle, the brachioradialis muscle, the extensor muscles of the fingers and wrist (extensor carpi radialis muscle), supinator, and the extensor and abductor muscles of the ...