1. Muscles of the Spine

2. Latissimus Dorsi Origin: Insertion: Action:
Spinous process of T6 through T12 and Lumbar vertebrae
Insertion:
Intertubercular groove of the Humerus
Inferior portion of scapula
Action:
Lateral trunk flexion
Anterior rotation of the pelvis

5. Trapezius

6. Trapezius Upper 1/3: Origin: Insertion: Action Occipital protuberance
Spinous process of C7
Insertion:
Distal/lateral 1/3 of Clavicle
Acromion Process
Action
Elevation of Scapula
Upward rotation of Scapula
Rotation of Scapula to the opposite side

8. Trapezius Middle 1/3: Origin: Insertion: Action:
Spinous processes of the 7th cervical vertebrae, & T1-T5
Insertion:
Acromion Process
Spine of the scapula (superior-lateral border)
Action:
Retraction of scapula
Fixation of thoracic spine

10. Trapezius Lower 1/3: Origin: Insertion: Action:
Spinous processes & Supraspinal ligaments of T8-T12
Insertion:
Spine of Scapula (medial portion)
Action:
Depression of Scapula
Retraction of Scapula
Fixation of thoracic spine

12. Serratus Anterior

13. Serratus Anterior Origin: Insertion: Action:
Anterior surface of the first 8-9 ribs
Insertion:
Anterior surface of medial border of scapula
Action:
Abducts (protracts) and upwardly rotates scapula; stabilizes scapula

14. Iliocostalis Origin: Insertion: Actions: Iliac Crest, Ribs 3-12
Ribs 1-12, Transvers processes of C4-C7
Actions:
Laterally Flexes, extends the spine

16. Longissimus Origin: Insertion: Actions:
Common erector spinae tendon, Transverse processes of T1-T5, Articular processes of C5-C6
Insertion:
Transverse processes of T3-T12, Ribs 1-12, Transverse processes of C2-C6, Mastoid process of skull
Actions:
Extension & lateral bending of spine, extension of skull and cervical spine, rotation of the face toward same side

18. Rhomboids Major: Minor: Actions: Origin: Insertion:
Spinous Processes of T2-T5
Insertion:
Vertebral border of scapula (lower 2/3)
Minor:
Spinous Processes of C7-T1
Vertebral border of scapula (upper 1/3)
Actions:
Retraction, elevation, downward rotation of scapula; Fixation of thoracic spine