Back and Pelvic Floor Muscles

MSK 2

serratus posterior superior origin

spinous processes of low cervical and upper thoracic spine

serratus posterior superior inseriton

posterolateral aspect of ribs 2-4

serratus posterior superior action

elevates superior ribs to assist with inspiration

serratus posterior inferior origin

spinous processes of T11-L2

serratus posterior inferior insertion

last 3 or 4 ribs

serratus posterior inferior action

assists inspiration by stabilizing lower ribs

splenius capitus origin

spinous processes of C7-T3

splenius capitus insertion

lateral occiput

splenius capitus bilateral action

extension of head and neck

splenius capitus unilateral action

ipsalateral sidebend and rotation

splenius cervicis origin

spinous processes of T3-T6

splenius cervicis insertion

transverse processes of C1-C3

splenius cervicis bilateral action

extension of head and neck

splenius cervicis unilateral action

ipsalateral sidebend and rotation

iliocostalis regions

lumborum, thoracis, cervicis

most superior attachment of iliocostalis

transverse processes of C4-C6

most inferior attachment of iliocostalis

iliac crest and sacrum via lumbodorsal fascia

iliocostalis action

extension, ipsalateral sidebend

longissimus regions

thoracis, cervicis, capitis

most superior attachment of longissimus

mastoid process

most inferior attachment of longissimus

transverse processes of lumbar vertebrae

longissimus thoracis and cervicis action

extension, ispalateral sidebend

longissimus capitus action

extend and ipsalateral rotation

spinalis regions

thoracis, cervicis, capitis

most superior spinalis attachment

skull

most inferior spinalis attachment

spinous processes of thoracic vertebrae

spinalis thoracis and cervicis action

extension and ipsalateral sidebending

spinalis capitus action

extension of head and neck

what are the 3 erector spinae muscles?

iliocostalis, longissimus, spinalis

what are the 3 deep spinal muscles, superficial to deep?

semispinalis, multifidus, rotatores

semispinalis regions

thoracis, cervicis, capitis

most superior semispinalis attachment

occipital bone between superior and inferior nuchal lines

most inferior semispinalis attachment

transverse processes of T7-T12

semispinalis action

extend spine, contralateral rotation

multifidus origin

sacrum, lumbar vertebrae facet joints, transverse processes of thoracic vertebrae

how many segments does multifidus cross?

2-5

multifidus action

contralateral rotation

rotatores origin

transverse processes of vertebrae

rotatores long rotators insertion

cross one vertebrae to spine of the second

rotatores short rotators insertion

base of spine of adjacent upper vertebrae

rotatores action

stabilize spine, contralateral rotation

where are interspinales best developed?

cervical spine

where are intertransversarii best developed?

cervical and lumbar vertebrae

rectus capitus anterior origin

lateral mass of atlas

rectus capitus anterior insertion

base of skull anterior to occipital condyle

rectus capitus anterior action

flexion and ipsalateral sidebend of head

rectus capitus lateralis origin

transverse process of atlas

rectus capitus lateralis insertion

jugular process of occipital bone

rectus capitus lateralis action

flexion and ipsalateral sidebend of head

rectus capitus posterior major origin

C2 spinous process

rectus capitus posterior major insertion

occipital bone

rectus capitus posterior major action

head extension and ipsalateral sidebend

rectus capitus posterior minor origin

C1 posterior tubercle

rectus capitus posterior minor insertion

occipital bone medial to RCPMj

rectus capitus posterior minor action

extension of head

obliquus capitus inferior origin

C2 spinous process

obliquus capitus inferior insertion

transverse process of C2

obliquus capitus inferior action

ispalateral head rotation

obliquus capitus superior origin

transverse process of C2

obliquus capitus superior insertion

occipital bone lateral to RCPMn

obliquus capitus superior action

extension and ipsalateral sidebend

levator ani origin

pelvic surface of inominate from body of pubis to spine of ischium

levator ani insertion

itself, anal canal, coccyx

levator ani action

acts as a sling to support pelvic viscera

coccygeus origin

ischial spine

coccygeus insertion

lower end of sacrum and coccyx

coccygeus action

acts as a sling to support pelvic viscera