Anatomy - MOINA of the Deep Muscles of the Back

origin of erector spinae

• iliac crest and sacrum

• transverse and spinous processes of vertebrae

• supraspinal ligament

insertion of erector spinae

• angles of the ribs

• transverse and spinous processes of vertebrae

• posterior aspect of the skull

innervation of erector spinae

segmentally innervated by dorsal primary rami of spinal nerves C1-S5

action of erector spinae

extends and laterally bends the trunk, neck, and head

origin of iliocostalis

iliac crest and sacrum

insertion of iliocostalis

angles of the ribs

innervation of iliocostalis

dorsal primary rami of spinal nerves C4-S5

action of iliocostalis

extends and laterally bends the trunk and neck

origin of interspinales

upper border of spinous process

insertion of interspinales

lower border of spinous process above

innervation of interspinales

dorsal primary rami of spinal nerves C1-L5

action of interspinales

extend trunk and neck

origin of intertransversarii

upper border of transverse process

insertion of intertransversarii

lower border of transverse process above

innervation of intertransversarii

dorsal primary rami of spinal nerves C1-L5

action of intertransversarii

laterally bend trunk and neck

origin of longissimus

transverse process at inferior vertebral levels

insertion of longissimus

• transverse process at superior vertebral levels

• mastoid process

innervation of longissimus

dorsal primary rami of spinal nerves C1-S1

action of longissimus

extends and laterally bends the trunk, neck, and head

origin of multifidus

• sacrum

• transverse processes of C3-L5

insertion of multifidus

spinous processes of 2-4 vertebral levels superior to their origin

innervation of multifidus

dorsal primary rami of spinal nerves C1-L5

action of multifidus

• extend and laterally bend trunk and neck

• rotate to opposite side

origin of obliquus capitis inferior

spinous process of the axis

insertion of obliquus capitis inferior

transverse process of atlas

innervation of obliquus capitis inferior

suboccipital nerve (DPR of C1)

action of obliquus capitis inferior

rotates the head to the same side

origin of obliquus capitis superior

transverse process of atlas

insertion of obliquus capitis superior

occipital bone above inferior nuchal line

innervation of obliquus capitis superior

suboccipital nerve (DPR of C1)

action of obliquus capitis superior

• extends the head

• rotates the head to the same side

origin of rectus capitis posterior major

spinous process of axis

insertion of rectus capitis posterior major

inferior nuchal line

innervation of rectus capitis posterior major

suboccipital nerve (DPR of C1)

action of rectus capitis posterior major

• extends the head

• rotates to same side

origin of rectus capitis posterior minor

posterior tubercle of atlas

insertion of rectus capitis posterior minor

inferior nuchal line medially

innervation of rectus capitis posterior minor

suboccipital nerve (DPR of C1)

action of rectus capitis posterior minor

extends the head

origin of rotatores

transverse processes

insertion of rotatores

• long rotatores: spines 2 vertebrae above origin

• short rotatores: spines 1 vertebrae above origin

innervation of rotatores

dorsal primary rami of spinal nerves C1-T12

action of rotatores

rotates the vertebral column to the opposite side

origin of semispinalis

transverse processes of C7-T12

insertion of semispinalis

• capitis: back of skull between nuchal lines

• cervicis & thoracis: spines 4-6 vertebrae above origin

innervation of semispinalis

dorsal primary rami of spinal nerve C1-T12

action of semispinalis

• extends the trunk and laterally rotates the trunk

• rotates the trunk to the opposite side

origin of serratus posterior inferior

• thoracolumbar fascia

• spines of vertebrae T11-T12 and L1-L2

insertion of serratus posterior inferior

ribs 9-12, lateral to the angles

innervation of serratus posterior inferior

branches of the ventral primary rami of spinal nerves T9-T12

action of serratus posterior inferior

pulls down lower ribs

origin of serratus posterior superior

• ligamentum nuchae

• spines of vertebrae C7 and T1-T3

insertion of serratus posterior superior

ribs 1-4, lateral to the angles

innervation of serratus posterior superior

branches of the ventral primary rami of spinal nerves T1-T4

action of serratus posterior superior

elevates the upper ribs

origin of spinalis

spinous processes at inferior vertebral levels

insertion of spinalis

• spinous processes at superior vertebral levels

• base of the skull

innervation of spinalis

dorsal primary rami of spinal nerves C2-L3

action of spinalis

extends and laterally bends trunk and neck

origin of splenius

• ligamentum nuchae

• spines C7-T6

insertion of splenius

• capitis:

  • mastoid process

  • superior nuchal line laterally

• cervicis: posterior tubercles of C1-C3 vertebrae

innervation of splenius

dorsal primary rami of spinal nerves C2-C6

action of splenius

• extends and laterally bends neck and head

• rotates head to same side

origin of splenius capitis

• ligamentum nuchae

• spines of C7-T6 vertebrae

insertion of splenius capitis

• mastoid process

• lateral end of the superior nuchal line

innervation of splenius capitis

dorsal primary rami of spinal nerves C2-C6

action of splenius capitis

• laterally bends the neck and head

• rotates head to the same side

origin of splenius cervicis

• ligamentum nuchae

• spines of C7-T6 vertebrae

insertion of splenius cervicis

posterior tubercles of the transverse processes of C1-C3 vertebrae

innervation of splenius cervicis

dorsal primary rami of spinal nerves C2-C6

action of splenius cervicis

• extends and laterally rotates neck and head

• rotates head to the same side