Unit 3: Axial Skeleton Musculature Flashcards
Action:
-Unilaterally, laterally flex vertebral column to the same side
-Unilaterally rotate vertebral column to the opposite side
-Bilaterally flex the vertebral column
-Bilaterally compress abdominal contents
Origin:
-External surfaces of fifth to twelfth ribs
Insertion:
-Anterior part of the iliac crest, rectus sheath to linea alba
External Oblique
Action:
-Unilaterally, laterally flex vertebral column to the same side
-Unilaterally rotate vertebral column to the same side
-Bilaterally flex the vertebral column
-Bilaterally compress abdominal contents
Origin:
-Lateral inguinal ligament, iliac crest and thoracolumbar fascia
Insertion:
-Internal surface of lower three ribs, rectus sheath to linea alba
Internal Oblique
Action:
-Compress abdominal contents
Origin:
-Lateral inguinal ligament, iliac crest, thoracolumbar fascia, and internal surface of lower six ribs
Insertion:
-Rectus sheath to linea alba
Transverse Abdominis
Action:
-Flex the vertebral column
-Tilt pelvis posteriorly
Origin:
-Pubic crest, pubic symphysis
Insertion:
-Cartilage of fifth, sixth, and seventh ribs and xiphoid process
Rectus Abdominis
Action:
-Draw down the central tendon of the diaphragm
-Increase the volume of the thoracic cavity during inhalation
Origin:
-Costal Attachment: Inner surface of lower six ribs
-Lumbar Attachment: Upper two or three lumbar vertebrae
-Sternal Attachment: Inner part of xiphoid process
Insertion:
-Central tendon
Diaphragm
Action:
-Draw the ribs superiorly (increasing the space of the thoracic cavity) to assist with inhalation
Origin:
-Inferior border of the rib above
Insertion:
-Superior border of the rib below
External Intercostals
Action:
-Draw the ribs inferiorly (decreasing the space of the thoracic cavity) to assist with exhalation
Origin:
-Inferior border of the rib above
Insertion:
-Superior border of the rib below
Internal Intercostals
Action:
-Unilaterally, laterally flex vertebral column to the same side
-Bilaterally extend the vertebral column
Origin:
-Common tendon (thoracolumbar fascia) that attaches to the posterior surface of sacrum, iliac crest, spinous processes of the lumbar and last two thoracic vertebrae
Insertion:
-Various attachments at the posterior ribs, spinous and transverse processes of thoracic and cervical vertebrae and mastoid process of temporal bone
Erector Spinae Group
Action:
-Unilaterally, laterally flex vertebral column to the same side
-Bilaterally extend the vertebral column
Origin:
-Spinous processes of the upper lumbar and lower thoracic vertebrae
-Ligamentum nuchae, spinous process of C7
Insertion:
-Spinous processes of upper thoracic
-Spinous processes of cervicals, except C1
Spinalis
Action:
-Unilaterally, laterally flex vertebral column to the same side
-Bilaterally extend the vertebral column
Origin:
-Common tendon
-Transverse processes of upper five thoracic vertebrae
Insertion:
-Lower nine ribs and transverse processes of thoracic vertebrae
-Transverse processes of cervical vertebrae
-Mastoid process of temporal bone
Longissimus
Action:
-Unilaterally, laterally flex vertebral column to the same side
-Bilaterally extend the vertebral column
Origin:
-Common tendon
-Posterior surface of ribs 1-12
Insertion:
-Transverse processes of lumbar vertebrae 1-3 and posterior surface of ribs 6-12
-Posterior surface of ribs 1-6
-Transverse processes of lower cervicals
Iliocostalis
Action:
-Unilaterally rotate the vertebral column to the opposite side
-Bilaterally extend the vertebral column
Origin:
-Sacrum and transverse processes of lumbar through cervical vertebrae
Insertion:
-Spinous processes of lumbar vertebrae through second cervical vertebra
Multifidi
Action:
-Unilaterally rotate the vertebral column to the opposite side
-Bilaterally extend the vertebral column
Origin:
-Transverse processes of lumbar through cervical vertebrae
Insertion:
-Spinous processes of lumbar vertebrae through second cervical vertebra
Rotatores
Action:
-Unilaterally, laterally tilt the pelvis
-Unilaterally, laterally flex the vertebral column to the same side
-Unilaterally, assist to extend the vertebral column
-Bilaterally fix the last rib during forced inhalation and exhalation
Origin:
-Posterior iliac crest
Insertion:
-Last rib and transverse processes of first through fourth lumbar vertebrae
Quadratus Lumborum
Action:
-Unilaterally, laterally flex the head and neck to the same side
-Unilaterally, rotate the head and neck to the opposite side
-Bilaterally flex the neck
-Bilaterally assist to elevate the rib cage during inhalation
Origin:
-Sternal head: top of manubrium
-Clavicular head: medial one-third of the clavicle
Insertion:
-Mastoid process of temporal bone and the lateral portion of superior nuchal line of occiput
Sternocleidomastoid
Action:
-Unilaterally, with the ribs fixed, laterally flex the head and neck to the same side
-Unilaterally, rotate head and neck to the opposite side
-Bilaterally elevate the ribs during inhalation
-Bilaterally flex the head and neck
Origin:
-Transverse processes of third through sixth cervical vertebrae
Insertion:
-First rib
Anterior Scalene
Action:
-Unilaterally, with the ribs fixed, laterally flex the head and neck to the same side
-Unilaterally rotate head and neck to the opposite side
-Bilaterally elevate the ribs during inhalation
Origin:
-Transverse processes of second through seventh cervical vertebrae
Insertion:
-First rib
Middle Scalene
Action:
-Unilaterally, with the ribs fixed, laterally flex the head and neck to the same side
-Unilaterally rotate head and neck to the opposite side
-Bilaterally elevate the ribs during inhalation
Origin:
-Transverse processes of sixth and seventh cervical vertebrae
Insertion:
-Second rib
Posterior Scalene
Action:
-Unilaterally rotate the head and neck to the same side
-Unilaterally, laterally flex the head and neck
-Bilaterally extend the head and neck
Origin:
-Inferior one-half of ligamentum nuchae and spinous processes of C7 to T4
Insertion:
-Mastoid process and lateral portion of superior nuchal line
Splenius Capitis
Action:
-Extend the vertebral column and head
Origin:
-Transverse processes of C4 to T5
Insertion:
-Between the superior and inferior nuchal lines of the occiput
Semispinalis Capitis
Action:
-Rock and tilt the head back into extension
-Rotate the head to the same side
Origin:
-Spinous process of the axis
Insertion:
-Inferior nuchal line of the occiput
Rectus Capitis Posterior Major
Action:
-Rock and tilt the head back into extension
Origin:
-Tubercle of the posterior arch of the atlas
Insertion:
-Inferior nuchal line of the occiput
Rectus Capitis Posterior Minor
Action:
-Rotate the head to the same side
Origin:
-Spinous process of the axis
Insertion:
-Transverse process of the atlas
Oblique Capitis Inferior
Action:
-Rock and tilt the head back into extension
Origin:
-Tubercle of the posterior arch of the atlas
Insertion:
-Inferior nuchal line of the occiput
Oblique Capitis Superior
