The anterior compartment of the arm - muscles (dave's notes) Flashcards
What are the muscles of the anterior compartment of the arm?
Coracobrachialis
Biceps brachii
Brachialis
What is the origin of coracobrachialis?
The coracoid process of the scapula with biceps brachii
What is the origin of biceps brachii?
The long head from supraglenoid tubercle of scapula. Short head from coracoid process
What is the origin of brachialis?
The anterior lower 1/2 of jumpers and the medial and lateral intermuscular septa
What is the insertion of coracobrachialis
The middle 3rd of the medial border of the humerus
What is the insertion of biceps brachii?
The posterior border of the bicipital tuberosity of radius and bicipital aponeurosis to deep fascia and sub cut ulna
What is the insertion of brachialis?
The coronoid process and tuberosity of the ulna
What is the action of coracobrachialis?
Flexes and weakly adducts the arm
What is the action of biceps brachii?
Supinates forearm, flexes elbow, weakly flexes shoulder
What is the action of brachialis?
Flexes elbow
What is the nerve to coracobrachialis?
The musculocutaneous nerve (C5,6,7), lateral cord
What is the nerve to biceps brachii?
The musculocutaneous nerve (C5,6), from lateral cord
What is the nerve to brachialis?
The musculocutaneous nerve (C5,6, from the lateral cord. Also a small supply from the radial nerve.
What is notable about the attachments of biceps brachii?
It has no attachments to the humerus
What is notable about the nerve supply to brachialis?
In addition to the musculocutaneous nerve, it receives a small supply from the radial nerve
