Spine Muscles

Superficial layer (in to out)

Splenius capitis

Splenius cervicis

Splenius capitis

Splenius capitis Origin

Lower half of ligamentum nuchae and spinous processes of upper thoracic vertebrae

Splenius capitis Insertion

Mastoid process of temporal bone and adjacent to occipital bone

Splenius capitis Innervation

Dorsal rami of cervical spinal nerves

Splenius capitis Action

Bilateral extension of neck and head, unilateral side of bending and rotation to the same side

Splenius cervicis

Splenius cervicis Origin

Lower half of ligamentum nuchae and spinous processes of upper thoracic vertebrae

Splenius cervicis Insertion

Transverse processes of upper cervical vertebrae

Splenius cervicis Innervation

Dorsal rami of cervical spinal nerves

Splenius cervicis Action

Bilateral extension of neck, unilateral side bending and rotation to same side

Erector Spinae - Intermediate Layer

iliocostalis, longissimus, spinalis

Iliocostalis muscles

lumborum, thoracis, cervicis

Iliocostalis

Iliocostalis insertions

lumborum - iliac crest

thoracis - lower 6 ribs

cervicis - upper 6 ribs

Iliocostalis Insertions

Lumborum - lower 6 ribs

Thoracis - upper 6 ribs

Cervicis - Transverse processes of cervical vertebrae

Iliocostalis Innervation

Dorsal rami of sp. nerves

Iliocostalis Action

Extension and side bending of spine

Longissimus muscles

thoracis, cervicis, capitis

Longissimus

Longissimus Origin

Thoracis - Sacrum and transverse process of lumbar vertebrae

Cervicis - Transverse processes of thoracic vertebrae/ribs

Capitis - Transverse processes of cervical vertebrae

Logissimus Insertion

Thoracis - Transverse processes of thoracic vertebrae/ribs

Cervicis - Transverse processes of cervical vertebrae

Capitis - Mastoid process

Longissimus Innervation

Dorsal rami of sp. nerves

Longissimus Action

Extension and spine bending of spine

Capitis rotates head toward same side

Spinalis

Spinalis muscles

thoracis, cervicis, capitis

Spinalis Origin

Spinous processes

Spinalis Insertion

Spinous processes

Spinalis Innervation

Dorsal rami of sp. nerves

Spinalis Action

Extension of spine

Tranversospinalis layer - deep layer (out to in)

Semispinalis

multifindus

rotatores

interspinales

intertransversarii

Semispinalis

Semispinalis muscles

capitis, cervicis, thoracis

Semispinalis origin

transverse processes

Semispinalis Insertion

thoracis - spinous processes

cervicis - spinous processes C2-C5

capitis - occipital bone

Semispinalis Innervation

Dorsal rami of the sp. nerves

Semispinalis Action

Extension and rotation of the

spine toward the opposite side

Exception: Semispinalis Capitis does not do rotation

Multifidus

Multifidus Origin

Sacrum, iliac crest, and transverse processes

Multifidus Insertion

All spinous processes

Multifidus Innervation

Dorsal rami of sp. nerve

Multifidus Action

Extension and rotation of the

spine toward the opposite side

Rotatores

Rotatores Origin

Transverse processes

Rotatores Insertion

All spinous processes

Rotatores Innervation

Dorsal rami of sp. nerves

Rotatores Action

Extension and rotation of the

spine toward the opposite side

Interspinales

Interspinales Origin

Connect spines of contiguous vertebrae

Interspinales Insertion

All spinous processes

Interspinales Innervation

Dorsal rami of sp. nerves

Interspinales Action

Extension of the spine

Intertransversarii

Intertransversarii Origin

Connect transverse processes of contiguous vertebrae

Intertransversarii Insertion

All spinous processes

Intertransversarii Innervation

Dorsal rami of sp. nerves

Intertransversarii Action

Side bending of the spine

Suboccipital Muscles

Rectus capitis posterior major

Rectus capitis posterior minor

Obliquus capitis inferior

Obliquus capitis superior

Rectus capitis major

Rectus capitis major Origin

Spine of axis (C2)

Rectus capitis major Insertion

Lateral part of inferior nuchal line of occipital bone

Rectus capitis major Innervation

Dorsal ramus C1 (suboccipital nerve)

Rectus capitis major Action

Extension of head and rotation to the same side

Rectus capitis minor

Rectus capitis minor Origin

Posterior aspect of atlas (C1)

Rectus capitis minor Insertion

Medial part of inferior nuchal line

Rectus capitis minor Innervation

Dorsal ramus of C1 (suboccipital nerve)

Rectus capitis minor Action

Extension of head

Obliquus capitis inferior

Obliquus capitis inferior Origin

Spine of axis (C2)

Obliquus capitis inferior Insertion

Transverse process of atlas

Obliquus capitis inferior Innervation

Dorsal ramus C1 (suboccipital nerve)

Obliquus capitis inferior Action

Rotation of head to the same side

Obliquus capitis superior

Obliquus capitis superior Origin

Transverse process of atlas (C1)

Obliquus capitis superior Insertion

Occipital bone between superior and inferior nuchal lines

Obliquus capitis superior Innervation

Dorsal ramus C1 (suboccipital nerve)

Obliquus capitis superior Action

Extension and side bending of head