Lab 1 - Back, Spine & Spinal Cord

Question 1

iliocostalis

action, innervation, inferior / superior attachment?

Answer 1

action

1) spine extension (bilateral contraction)
2) lateral bending (unilateral contraction)

innervation

posterior rami of lumbar, thoracic, and cervical spinal nerves

inferior attachment

pelvis (iliac crest), sacrum, L5-L1 vertebrae (spinous processes)

superior attachment

ribs 1-12 (angles)

T12-C3 vertebrae (transverse processes)

Note: iliocostalis = lumborum, thoracis, cervicis

Question 2

longissimus

action, innervation, inferior/superior attachment?

Answer 2

action

1) spine extension (bilateral contraction)
2) lateral bending (unilateral contraction)

innervation

posterior rami of lumbar, thoracic, and cervical spinal nerves

inferior attachment

L4-T1 vertebrae (transverse processes)

superior attachment

ribs 1-12 (lateral to tubercles), C7-C3 vertebrae (transverse processes), temporal bone (mastoid process)

Note: longissimus = lumborum, thoracis, cervicis

Question 3

spinalis

action, innervation, inferior / superior attachment?

Answer 3

action

upper spine or atlanto-occipital joint extension (bilateral contraction)

innervation

posterior rami of thoracic and cervical spinal nerves

inferior attachment

L5-T1 vertebrae (spinous processes)

superior attachment

T12-C7 vertebrae (spinous processes)

occipital bone (between superior and inferior nuchal lines)

Note: spinalis = thoracis, cervicis, capitis

Question 4

what are the 3 erector spinae muscles, starting laterally and moving medially toward spine?

Answer 4

iliocostalis

longissimus

spinalis