Shoulder muscles

• Levator scapulae ventralis

  O: Transverse process of atlas and occipital bone

  I: Metacromion process and neighboring fascia

  A: Draws the scapula craniad
• Latissimus dorsi

  O: Neural spines of the last thoracic and most of lumbar vertebrae and from the lumbodorsal fascia

  I: Tendon on the medial surface of the humerus

  A: Retraction of the humerus
• Spinotrapezius

  O: Spines of thoracic vertebrae and passes obliquely forward, covering part of the latissimus

  I: Fascia of scapula

  A: Draws scapula dorsad and caudad
• Acromiotrapezius

  O: Neural spines of cervical and first thoracic vertebrae

  I: Metacromion process and spine of scapula and fascia of spinotrapezius

  A: Draws scapula dorsad and holds two scapulae together
• Rhomboideus

  O: Neural spines of vertebrae and adjacent ligaments

  I: Vertebral border of the scapula

  A: Draws the scapula dorsad and medial
• Clavodeltoideus

  O: Raphe at the level of the clavicle with the clavotrapezius

  I: Ulna

  A: Protracts arm or flexes forearm
• Acromiodeltoideus

  O: Acromion process

  I: Spinodeltoid and brachialis muscles and on the deltoid ridge of the humerus

  A: Retracts and abducts humerus
• Spinodeltoideus

  O: Spine of scapula

  I: Deltoid ridge of humerus

  A: Retracts and abducts humerus
• Supraspinatus

  O: Whole surface of the supraspinous fossa

  I: Greater tuberosity of the humerus, near the insertion of the pectoralis minor

  A: Protracts/extends the humerus
• Infraspinatus

  O: Infraspinous fossa

  I: Greater tuberosity of the humerus

  A: Rotates the humerus outward
• Subscapularis

  O: Subscapular fossa

  I: Lesser tuberosity of the humerus

  A: Pulls the humerus medially
• Teres major

  O: Glenoid border of the scapula and fascia of neighboring muscles

  I: Medial surface of the humerus

  A: Rotates and retracts humerus
• Teres minor

  O: Glenoid border of scapula

  I: Greater tuberosity of humerus

  A: Assists the infraspinatus
• Serratus ventralis

  O: Slips from the first nine or ten ribs

  I: Scapula near the ventral border

  A: Draws scapula ventrad and supports trunk
• Levator scapulae

  O: Transverse processes of the last five cervical vertebrae

  I: Scapula near the ventral border

  A: Draws the scapula craniad