Anatomy Week 8: Abdomen PAOIN

Splenius Capitis

Splenius Capitis PA

social interaction and driving

Splenius Capitis action

cervical extension

Splenius Capitis Origin

Nuchal ligament and spinous processes of C7-T4

Splenius Capitis insertion

Superolaterally to mastoid process

Splenius Capitis innervation

posterior rami of spinal nerves

Spelnius Cervicus

Spelnius Cervicus pa

social interaction, driving

Spelnius Cervicus action

Unilaterally: ipsilateral lateral cervical flexion and

rotation

Bilaterally: cervical extension

Spelnius Cervicus origin

Nuchal ligament and spinous processes of C&-T6

Spelnius Cervicus insertion

Tubercles of transverse processes of C1 - C3

Spelnius Cervicus innervation

posterior rami of spinal nerves

Spinalis

Spinalis PA

Maintaining upright posture for ADLS

Spinalis action

Unilaterally: ipsilateral lateral flexion of vertebral

column

Bilaterally: extension

Spinialis origin

broad tendon (thoracolumbar fascia)

spinalis insertion

Various attachments at posterior ribs

spinalis innervation

posterior rami of spainal nerves

Longissimus

Longissimus PA

upright posture for ADLs

Longissimus action

ipsilateral lateral flexion and extension of vertebral column

Longissimus origin

broad tendon

Longissoimus insertion

Various attachments at posterior ribs, spinous and

transverse processes of thoracic and cerical

vertebrae, and at mastoid process

Longissimus innervation

posterior rami of spinal nerves

Iliiocostalis

Iliiocostalis pa

maintaing upright posture for ADLS

Iliiocostalis action

ipsilateral lateral flexion and extension of vertebral

column

Iliocostalis orgin

broad tendon

iliocostalis insertion

various attachments at posterior ribs

iliocostalis innervation

posterior rami of spinal nerves

Semispinalis

Semispinalis pa

looking overhead

Semispinalis action

Unilaterally: contralateral rotation

Bilaterally: extension head, cervical, and thoracic regions

Semispinalis origin

• Capitis portion: superior attachment is on the occiput

• Cervicis portion: superior most attachment is spinous

process of C2 (important landmark for suboccipital region)

Semispinalis insertion

transverse processes of C4-T10 vertebrae

semispinalis innervation

posterior rami of spinal nerves

Multifidus

Multifidus pa

tai chi, yoga

Multifidus action

contralateral rotation

Multifidus origin

posterior sacrum

Multifidus insertion

Superior attachment: fibers pass obliquely superomedially to

entire length of spinous processes of vertebrae located two to

four segments superior to origin

Multifidus innervation

posterior rami of spinal nerves

Rotatores

Rotatores pa

tai chi, yoga

Rotatores action

contralateral rotation

rotatores origin

inferior attachment: transverse processes of lumbar through

cervical vertebrae

roatores insertion

Superior attachment: fibers pass obliquely superomedially to

entire length of spinous processes of vertebrae located one to

two segments superior to origin

rotatores innervation

posterior rami of spinal nerves

external oblique

external oblique pa

bed mobility, lifting

external oblique action

contralateral trunk rotation

external oblique origin

external surfaces of 5th-12th ribs

external oblique insertion

Linea alba, pubic tubercle, and anterior half of iliac crest

external oblique innervation

Thoracoabdominal and subcostal nerves

(anterior rami of T7-T12 spinal nerves)

Internal oblique

Internal oblique pa

bed mobility, lifting

internal oblique action

ipsilateral trunk flexion

internal oblique origin

Thoracolumbar fascia, anterior 2/3 of iliac crest, and connective tissue deep to inguinal ligament

internal oblique innervation

Thoracoabdominal nerves (anterior rami of T7-

T11), subcostal and first lumbar nerve

Transverse abdominus

transverse abdominis pa

carrying a child

transverse abdominis action

Increases tension in broad tendon

transverse abdomins origin

broad tendon, iliac crest

transverse abdomis insertion

linea alba with aponeruois of internal oblique, pubic crest, and pubis via conjoint tendon

transverse abdominis innervation

Thoracoabdominal nerves (anterior rami of T7-

T11), subcostal and first lumbar nerve

(iliohypogastric nerve)

Rectus abdominis

rectus abdominus pa

lower body dressing

rectus abdominus action

Flexes trunk (lumbar vertebrae)

• Stabilizes and controls tilt of pelvis

(antilordosis) - creates posterior pelvic tilt

rectus abdominus origin

pubic symphysis and pubic crest

rectus abdominis insertion

xiphoid process and 5th-7th costal cartilage

rectus abdomius innervation

Thoracoabdominal nerves

Quadratus lumborum

quadratus lumborum pa

walking, lifting

quadratus lumborum action

elevates pelvis

quadratus lumborum origin

medial half of inferior border of 12th rib and tips of lumbar transverse processes

quadratus lomborum insertion

posterior illiac crest

quadratus lomborum innervation

anterior rami of T12 and L1-L4 nerves

External intercostal

external intercostal pa

singing, playing trumpet

external intercostal action

Elevate ribs

external intercostal origin

inferior bodrder of ribs

external intercostal insertion

superior border of ribs below

external intercostal innervation

intercostal nerves

internal intercostal

internal intercostal pa

singing, playing the trumpet

internal intercostal action

depress and elevate ribs

internal intercostal origin

inferior border of ribs

internal intercostal insertion

superior bodrder of ribs below

internal intercostal innervation

intercostal ribs

innermost intercostals

innermost intercostals pa

singing

innermost intercostals action

depress and elevate ribs

innermost intercostals origin

inferior border of ribs

innermost intercostals insertion

superior border of ribs below

innermost intercostals innervation

intercostal nerves

subcostals

subcostals pa

singing

subcostals action

action similar to internal intercostals

subcostals origin

internal surface of lower ribs near their angles

subcostals insertion

superior borders of 2nd or 3rd ribs below