O: Spines of the thoracic vertabrae.

I: Fascia covering the supraspinatus and infraspinatus muscles of the scapula.

A: Pulls the scapula dorsocaudad.

O: Spines of the cervical through the first few thoracic vertebrae.

I: Along the spine of the scapule onto the fascia of the spinotrapezius.

A: Pulls the scapula dorsally and holds the scapula together. 

O: Posterior mid-dorsal region of the skull and spines of the first few cervical vertebrae.

I: Clavicle and the raphe between the clavotrapezius and the clavodeltoid.

A: Pulls the scapule craniodorsally.

O: From the clavotrapezius and the clavicle.

I: Proximal end of the ulna in conjunction with the brachialis muscle of the upper arm.

A: Flexes the forearm.

O: Acromion process of the scapula.

I: On the spinodeltoid fascia and on the deltoid ridge of the humerus.

A: Flexes the humerus and rotates it outward.

O: Spine of the scapula.

I: Deltoid ridge of the humerus.

A: Flexes the humerus and rotates it outward.

Levator Scapulae Ventralis

O: A) From the atlas

B) From the occipital bone of the skull.

I: Metacromion process of the scapula and the infraspinous fossa.

A: Pulls the scapula towards the head.

O: Neural spines of the fourth thoracic through the sixth lumbar vertebrae. 

I: On the medial surface of the humerus by fascia common to the xiphihumeralis and the pectoralis minor muscles.

A: Pulls the arm dorsally and caudually. 

O: First four thoracic spines.

I: Around the vertebral border of the scapula.

A: Pulls the scapula dorsally and towards the vertebral column.

O: Lambdoidal ridge of the skull under the clavotrapezius.

I: On the vertebral border of the scapula behind the rhomboideus.

A: Pulls the scapula towards the head, and rotates it.

O:From the fascia originating from the thoracic spine.

I: Lamdoidal Ridge of the skull.

A: Turns the head (one muscle of the pair contracting); raises the head (with both right and left muscles contracting).

O:Entire surface of the supraspinous fossa.

I: Greater tuberosity of the humerus.

A: Extends the humerus.

O: The entire surface of the infraspinous fossa. 

I: The greater tuberosity of the humerus.

A: Rotates the humerus outward.

O: Axillary border of the scapula and from the fascia of the infraspinatus and subscapularis muscles.

I:Medial surface of the humerus by a tendon common to the latissimus dorsi.

A: Rotates the humerus inward and flexes it.

O: Axillary border of the scapula near the glenoid cavity.

I: Greater tuberosity of the humerus.

A: Rotates the humerus outward.

O: Entire subscapular fossa.

I: Lesser tuberosity of the humerus.

A: Pulls the humerus medially.