Muscles of the Arm - Muscles of the Anterior Arm
Origin: supraglenoid tubercle of scapula Insertion: radial tuberosity (via common tendon with short head); deep fascia of forearm via bicipital aponeruosis Action: flexes forearm (at elbow joint) when forearm in supinated position; supinates forearm (at radioulnar joints); weak flexor of arm (at shoulder joint) Innervation: musculocutaneous nerve
Biceps brachii - long head
Origin: coracoid process of scapula Insertion: radial tuberosity (via common tendon with long head); deep fascia of forearm via bicipital aponeurosis Action: flexes forearm (at elbow joint) when forearm in supinated position; supinates forearm (at radioulnar joints); weak flexor of arm (at shoulder joint) Innervation: musculocutaneous nerve
Biceps brachii - short head
Origin: distal half of anterior surface of humerus Insertion: coronoid process of ulna; ulnar tuberosity Action: flexes forearm (at elbow joint) Innervation: musculocutaneous nerve
Brachialis
Origin: coracoid process of scapula Insertion: muddle of medial surface of shaft of humerus Action: flexes arm (at shoulder joint); adducts arm (at shoulder joint) Innervation: musculocutaneous nerve
Coracobrachialis
only muscle to flex arm (not forearm)
What is special about the coracobrachialis compared to other anterior arm muscles?
musculocutaneous nerve
Which nerve innervates all the muscles of the anterior arm?