Erector Spinae

Question 1

Name origin, insertion, action for erector muscle longissimus and nerve innervation

Answer 1

A: unilaterally rotates VC to same side and bilaterally extends the VC
O: common tendon (thoracis), TVP’s of upper five thoracic vertebrae (cervicis and capitis)
I: lower 9 ribs and TVPS of thoracic vertebrae (thoracic)
TVPS of cervical vertebrae (cervicis)
Mastoid process of temporal bone (capitis)
Nerve: Spinal

Question 2

Name action origin and insertion for iliocostalis. Give nerve innervation

Answer 2

A: Unilaterally flexes column to the same side bilaterally extends vertebral column
O: common lumborum tendon/ posterior surfaces of ribs 1-12 (thoracis and cervicis)
I: TVPS of lumbar vertebrae 1-3
posterior surfaces of ribs 6-12(lumborum)
Posterior surface of ribs 1-6 (thoracis)
TVPS of lower cervicals (cervicis)
Nerve: spinal

Question 3

What do the upper fibers of the longissimus and iliocostalis actions assist?

Answer 3

Extension, lateral flexion and rotation of the head and neck to the same side