1. Origin Insertion Nerve Action External Intercostal
Inferior border of the ribs
Insertion
Superior border of the ribs below
Nerve
Intercostal nerve
Action
Elevates Ribs

2. Origin Insertion Nerve Action Splenius Capitis Mastoid process
Nuchal ligament
spinous process of C7 – T3
Insertion
Mastoid process
superior nuchal line
Nerve
Posterior rami of spinal nerves
Action
Unilaterally – laterally bend to side of active muscles
Bilaterally – extend head and neck

3. Origin Insertion Nerve Action Erector Spinae
Iliac crest
Sacrum
Supraspinous ligament
Insertion
Iliocostalis - angles of lower ribs and transverse process
Longissimus - transverse process in thoracic and cervical regions , and to mastoid process
Spinalis - spinous process thoracic region and to skull
Nerve
Posterior rami of spinal nerves
Action
Unilaterally – laterally bend vertebral column to side of active muscles
Bilaterally – extend vertebral column and head

4. Origin Insertion Nerve Action Rhomboid Minor
Nuchal ligament
spinous process of C7 and T1 vertebrae
Insertion
Medial border of scapula from level of spine to inferior angle
Nerve
Dorsal scapular nerve
Action
Retracts scapula

5. Origin Insertion Nerve Action Deltoid Deltoid tuberosity of humerus
Clavicular- lateral third of clavicle
Acromial – Acromion
Spinal – Spine of scapula
Insertion
Deltoid tuberosity of humerus
Nerve
Axillary nerve
Action
Clavicular – flexes and medially rotates arm
Acromial – abducts arm
Spinal – extends & laterally rotates arms

6. Origin Insertion Nerve Action Serratus Anterior Ribs 1 - 9
Anterior surface of the medial border of the scapula
Nerve
Long thoracic nerve C5-C7
Action
Protracts scapula

7. Origin Insertion Nerve Action Teres Major
Inferior angle of the scapula
Insertion
Lesser tubercle
Nerve
Lower subscapular
Action
Adduct and internally rotates humerus

8. Origin Insertion Nerve Action Trapezius
Superior nuchal line
External occipital protuberance
Nuchal ligament
Spinous process of C7-T12
Insertion
Clavicle, acromion, spine of scapula
Nerve
Spinal accessory nerve
Action
Elevates, retracts, rotates scapula

9. Origin Insertion Nerve Action Rhomboid Major
Spinous process of T2-T5 vertebrae
Insertion
Medial border of scapula from level of spine to inferior angle
Nerve
Dorsal scapular nerve
Action
Retracts scapula

10. Origin Insertion Nerve Action Internal Intercostal
Inferior border of the ribs
Insertion
Superior border of the ribs below
Nerve
Intercostal nerve
Action
Depresses Ribs

11. Serratus Posterior Superior
Origin
Nuchal ligament
Spinous process C7-T3
Insertion
Ribs 2,3,4
Nerve
2nd-5th Intercostal nerves
Action
Elevates Ribs

12. Origin Insertion Nerve Action Quadratus lumborum 12th rib
lumbar transverse process
Insertion
Iliolumbar ligament
iliac crest
Nerve
Anterior rami of T12 & L1-L4 nerve
Action
Extends and laterally flexes (bends) vertebral column
Hip hiker

13. Serratus Posterior Inferior
Origin
Spinous process T11-L2
Insertion
Ribs 8-12
Nerve
Anterior rami T9-T12 nerve
Action
Depresses Ribs

14. Origin Insertion Nerve Action Infraspinatus
Infraspinatus fossa of scapula
Insertion
Greater tubercle of humerus
Nerve
Suprascapular nerve
Action
Laterally rotates arm

15. Origin Insertion Nerve Action Levator Scapulae
Transverse process of C1-C4
Insertion
Superior angle
Nerve
Dorsal scapular nerve
Action
Elevates scapula

16. Origin Insertion Nerve Action Splenius Cervicis
Nuchal ligament
spinous process of C7 – T3
Insertion
Transverse process of C1-C3
Nerve
Posterior rami of spinal nerves
Action
Unilaterally – laterally bend to side of active muscles
Bilaterally – extend head and neck

17. Origin Insertion Nerve Action Latissimus Dorsi Bicipital groove
Spinous process of T7-T12
Thoracolumbar fascia
Iliac crest
3 or 4 ribs
Insertion
Bicipital groove
Nerve
Thoracodorsal nerve C6
Action
Extends, adducts, medially rotates humerus

18. Origin Insertion Nerve Action Semispinalis
Thoracic and cervical transverse process
Insertion
Run superomedially
Attach to occipital bone and spinous process in thoracic & cervical regions
Nerve
Posterior rami of spinal nerves
Action
Unilaterally – rotate head and neck contralaterally
Bilaterally – extend head and thoracic cervical regions. Stabilizes vertebrae

19. Origin Insertion Nerve Action Multifidus
Sacrum and ilium
Transverse process of T1-L5
Articular process of C4-C7
Insertion
Run superomedially to spinous process
Nerve
Posterior rami of intercostal nerves
Action
Unilaterally – rotate head and neck contralaterally
Bilaterally – extend head and thoracic cervical regions. Stabilizes vertebrae

20. Origin Insertion Nerve Action Rotatores
Transverse process of vertebrae
Insertion
Run superomedially and attach to junction of lamina and transverse process
Nerve
Posterior rami of spinal nerves
Action
Stabilize vertebrae and assist with local extension and rotary movement