Erector Spinae Group

A: Unilaterally: Laterally flex vertebral column to the same side Bilaterally: Extend the vertebral column

O: Common tendon (thoracolumbar fascia) that attaches to the posterior surface of sacrum, iliac crest, spinous processes of the lumbar, and last two thoracic vertebrae

I: Various attachments at the posterior ribs, spinous and transverse processes of thoracic and cervical vertebrae, and mastoid process of temporal bone

               Transversospinalis Group

A: Unilaterally: Rotate the vertebral column to the opposite side.

Bilaterally: Extend the vertebral column

O: Multifidi: Sacrum and transverse processes of lumbar through cervical vertebrae.

Rotatores: Transverse processes of lumbar through cervical vertebrae.

I: Spinous processes of lumbar vertebrae through second cervical vertebra 

Semispinalis Capitis 

A: Extend the vertebral column and head

O: Transverse processes of C-4 to T-5

I: Between the superior and inferior nuchal lines of the occipul

Splenius Capitis and Cervicis

A: Rotate the head and neck to the same side Laterally flex the head and neck to the same side Bilaterally: Extend the head and neck.

O: Capitis: Inferior one-half of ligamentum nuchae and spinous processes of C-7 to T-4

I: Capitis: Mastoid process and lateral portion of superior nuchal line

Suboccipitals

A: Rock and tilt the head back into extension

Rotate the head to the same side

O: Laterally flex the head to the same side

I: Inferior nuchal line of the occiput

Quadratus Lumborum

A: Unilaterally: Laterally tilt (elevate) the pelvis Laterally flex the vertebral column to the same side Assist to extend the vertebral column

O: Posterior iliac crest

I: Last rib and transverse processes of first through fourth lumbar vertebrae

                            Rectus Abdominis

A: Flex the vertebral column

O: Tilt pelvis posteriorly Pubic crest, pubic symphysis

I: Cartilage of fifth, sixth, and seventh ribs and     xiphoid process

                               Diaphragm

A: Draw down the central tendon of the diaphragm Increase the volume of the thoracic cavity during inhalation

O: Costal attachment: Inner surface of lower six ribs Lumbar attachment: Upper two or three lumbar vertebrae Sternal attachment: Inner part of xiphoid process

I: Central tendon

Intercostals 

A: Draw the ribs superiorly (increasing the space of the thoracic cavity) to assist with inhalation/

    Draw the ribs inferiorly (decreasing the space of the thoracic cavity) to assist with exhalation

O: Inferior border of the rib above

I: Superior border of the rib below

              Serratus Posterior Superior

        A: Elevate the ribs during inhalation

        O: Spinous processes of C-7 to T-3 

        I: Posterior surface of second through fifth ribs

                  Serratus Posterior Inferior 

   A: Depress the ribs during exhalation

 O: Spinous processes of T-12 to L-3  

       I: Posterior surface of ninth through twelfth ribs

Intertransversarii

A: Unilaterally: Laterally flex the vertebral column to the same side Bilaterally: Extend the vertebral column

O: Cervical: Spanning the transverse processes of vertebrae C-2 to C-7

I: Lumbar: Spanning the transverse processes of vertebrae L-1 to L-5