Scapula muscles (OIA)

Origin: Trapezius

occipital bone

Insertion: Trapezius

acromion process

Action: Trapezius

elevation and adduction

Origin: Levator Scapula

C1-C4 transverse processes

Insertion: Levator Scapulae

medial border of scapula

Action: Levator Scapulae

elevation and downward rotation

Origin: Rhomboid minor

C7-T1 spinous processes

Insertion: Rhomboid minor

medial border

Action: Rhomboid minor

adduction, elevation, and downward rotation

Origin: Rhomboid major

T2-T5 spinous processes

Insertion: Rhomboid major

medial border to inferior angle

Action: Rhomboid major

adduction, elevation, and downward rotation

Origin: Serratus anterior

1-8th ribs

Insertion: Serratus anterior

superior angle, medial border, and inferior angle

Action: Serratus anterior

protraction

Origin: Pectoralis minor

3-5th ribs

Insertion: Pectoralis minor

coracoid process

Action: Pectoralis minor

depression, abduction, and downward rotation

Origin: Deltoids

acromian process and scapular spine

Insertion: Deltoids

deltoid tuberosity

Action: Deltoids

abduction past 15 degrees and flexion

Origin: Supraspinatus

supraspinatus fossa

Insertion: Supraspinatus

greater tubercle of the humerus

Action: Supraspinatus

initiates adduction from 0-15 degrees

Origin: Infraspinatus

Infraspinatus fossa

Insertion: Infraspinatus

Greater tubercle of the humerus

Action: Infraspinatus

external rotation

Origin: Teres minor

Lateral border

Insertion: Teres minor

greater tubercle

Action: Teres minor

externally rotates and adduction

Origin: Teres major

inferior angle

Insertion: Teres major

inter tubercular groove

Action: Teres major

internal rotation and adduction

Origin: Subscapularis

anterior aspect of the scapularis fossa

Insertion: Subscapularis

lesser tubercle of the humerus

Action: Subscapularis

internal rotation

Origin: Biceps Brachii

Long head: supraglenoid fossa, Short head: coracoid process

Insertion: Biceps Brachii

radial tuberosity

Action: Biceps Brachii

flexion of the elbow and supination of the wrist

Origin: Triceps Brachii

long head: infraglenoid tubercle*

Insertion: Triceps Brachii

olecranon process

Action: Triceps Brachii

extension of the elbow

Origin: Coracobrachialis

coracoid process

Insertion: Coracobrachialis

anteromedial surface of the humerus

Action: Coracobrachialis

flexion and adduction of the humerus

Origin: Inferior belly of Omohyoid

superior border of scapula

Insertion: Inferior belly of Omohyoid

intermediate tendon of the omohymoid

Action: Inferior belly of Omohyoid

depresses and retracts the hyoid bone

Origin: Latissimus dorsi

inferior angle of scapula

Insertion: Latissimus dorsi

bicipetal groove

Action: Latissimus dorsi

adduction, medial rotation, and extension of the arm