Week 9 Muscles Flashcards
Biceps Brachii
O: long head- supraglenoid tubercle of the scapula
short head- coracoid process of the scapula
I: tuberosity of the radius and bicipital aponeurosis
A: flexes the elbow at the humeroulnar joint
supinates the forearm at the radioulnar joints
flexes the shoulder at the glenohumeral joint
Triceps Brachii
O: long head- infraglenoid tubercle of the scapula
lateral head- proximal (one third of the) posterior shaft of the humerus
medial head- distal (two thirds of the) posterior shaft of the humerus medial head
I: olecranon process of the ulna
A: all heads- extends the elbow at the glenohumeral joint
long head- extends the shoulder at the glenohumeral joint
adducts the shoulder at the glenohumeral joint
horizontally abducts the shoulder at the glenohumeral joint
Brachialis
O: distal (half of the) anterior shaft of the humerus
I: tuberosity and coronoid process of the ulna
A: flexes the shoulder at the humeroulnar joint
Brachioradialis
O: proximal (two thirds of the) lateral supracondylar ridge of the humerus
I: lateral side of the styloid process of the radius
A: flexes the elbow at the humeroulnar joint
supinates* the forearm at the radioulnar joints
pronates* the forearm at the radioulnar joints
*Supination from pronation to neutral of the forearm and pronation from supination to neural of the forearm
Pronator Teres
O: medial epicondyle of the humerus and coronoid process of the ulna
I: middle (third) of lateral surface of the radius
A: pronates the forearm at the radioulnar joints
flexes the elbow at the humeroulnar joint
Supinator
O: lateral epicondyle of the humerus, supinator crest of the ulna and the proximal ulna*
I: anterior, lateral surface of proximal (one third of the) radial shaft
A: supinates the forearm at the radioulnar joints
*Supinator comes posteriorly off the ulna and wraps around the lateral radius to its insertion
