Superficial and Intermediate Layers of Intrinsic Back Muscles

Question 0

Where does the Splenius Capitis and Splenius Cervicis insert?

Answer 0

Splenius capitis - Fibers run superolaterally to mastoid process of temporal bone and lateral third of superior nuchal line of occipital bone

Splenius cervicis - tubercles of tranvserse processes of C1-C3 or C4 vertebrae

Question 1

Where is the origin of the Splenius muscles?

Answer 1

Arises from the nuchal ligament and spinous processes of C7-T6 vertebrae

Question 2

Nerve supply of Splenius?

Answer 2

Posterior rami of spinal nerves

Question 3

What are the actions of the splenius muscles?

Answer 3

Acting together : extend head and neck

Acting alone : laterally flex neck and rotate head to side of active muscles

Question 4

Origin of Illiocostalis, Longissimus & Spinalis (Erector Spinae) - Intermediate

Answer 4

Broad tendon from posterior part of the illiac crest, posterior surface of sacrum, sacro-Illiac ligaments, sacral and inferior lumbar spinous processes, and supra spinous ligament

Question 5

Insertion of Iliocostalis (lumborum, thoracis & cervicis)

Answer 5

fibers run superiorly to angles of lower ribs and cervical transverse processes

Question 6

Insertion of Longissimus (thoracis, cervicis, and capitis)?

Answer 6

fibers run superiorly to ribs between tubercles and angles to transverse processes in thoracic and cervical regions and to mastoid processes of temporal bone.

Question 7

Insertion of Spinalis (thoracis, cervicis, and capitis)?

Answer 7

fibers run superiorly to spinous processes in upper thoracic region and to cranium

Question 8

Nerve supply for Iliocostalis, longissimus, spinalis?

Answer 8

Posterior rami of spinal nerves

Question 9

Actions of Iliocostalis, longissimus & spinalis?

Answer 9

Acting bilaterally - extend vertebral column and head as back is flexed, control movement by gradually lengthening their fibers.

Acting unilaterally - laterally flex vertebral column