Erectors & Deep Vertebral Muscles

Question 1

Illiocostalis Regions and General Positioning

Answer 1

Lumborum, Thoracis, Cervicis
O - Common tendon of erector spinae arising from posterior iliac crest, posterior surface of sacrum, posterior sacroiliac ligaments, sacral and inferior spinous processes, and supraspinous ligaments
I - Superiorly to angles of middle ribs, and cervical and lumbar transverse processes

Question 2

Longissimus Regions and General Positioning

Answer 2

Thoracis, Cervicis, Capitis
O - Common tendon of erector spinae arising from posterior iliac crest, posterior surface of sacrum, posterior sacroiliac ligaments, sacral and inferior spinous processes, and supraspinous ligaments
I - Superiorly to ribs between its tubercles and its angles, to transverse processes in thoracic and cervical regions, and to mastoid process of temporal bone

Question 3

Spinalis Regions and General Positioning

Answer 3

Thoracis, Cervicis, Capitis
O - Common tendon of erector spinae arising from posterior iliac crest, posterior surface of sacrum, posterior sacroiliac ligaments, sacral and inferior spinous processes, and supraspinous ligaments
I - Superiorly to spinous processes in upper thoracic, cervical, and to occipital bone (inseparable with semispinalis)

Question 4

Semispinalis Regions and General Positioning

Answer 4

Thoracis, Cervicis, Capitis
O - Transverse processes of C4-T12
I - Superomedial spinous processes from origin, spanning 4-6 segments above origins, and ending into occipital bone (longest spanning of deep layer)

Question 5

Multifidus

Answer 5

O - Posterior surface of sacrum, posterior superior iliac spine of ilium, sacroiliac ligaments, aponeurosis of erector spinae, mammillary processes of lumbar vertebrae, transverse processes of T1-T3, and articular processes of C4-C7
I - Superomedially, to superior spinous processes of vertebrae (2-4 vertebrae) above origin; thickest in lumbar region

Question 6

Rotatores

Answer 6

O - Transverse processes of all vertebrae; thickest in thoracic region
I - Brevis head: immediately above origin, to junction of lamina and transverse process, or right to its spinous process; Longus head: 2 vertebrae above origin, to junction of lamina and transverse process, or right to its spinous process

Question 7

Interspinales

Answer 7

O - Superior surfaces of spinous processes of cervical and lumbar vertebrae
I - Inferior surfaces of spinous processes of vertebrae superior to origin

Question 8

Intertransversarii

Answer 8

O - Transverse processes of cervical and lumbar vertebrae

I - Adjacent transverse processes of above vertebrae

Question 9

Levatores Costarum

Answer 9

O - Tips of transverse processes of C7-T11

I - Pass inferolaterally and insert onto ribs between tubercle and angle