Muscle actions

  1. Serratus posterior superior
    Elevates the upper ribs but maybe not in respiration
  2. Serratus posterior inferior
    Possibly involved in respiration
  3. Splenious capitis
    • -Bilaterally extends head and neck
    • -Unilaterally side bends and rotates the head and neck to same side
  4. Splenius cervicis
    • -Bilaterally extends head and neck
    • -Unilaterally side bends and rotates the head and neck to same side
  5. Iliocostalis cervicis, thoracis, and lumborum
    • -acting bilaterally, extends spine and head
    • -acting unilaterally, side bends and rotates spine and head to same side
    • -portions that originate on pelvis can anteriorly tilt the pelvis
  6. Longissimus capitis, cervicis, and thoracis
    • -acting bilaterally, extends spine and head
    • -acting unilaterally, side bends and rotates spine and head to same side
    • -portions that originate on pelvis can anteriorly tilt the pelvis
  7. Spinalis thoracis, (sometimes cervicis)
    • -acting bilaterally, extends spine and head
    • -acting unilaterally, side bends and rotates spine and head to same side
    • -portions that originate on pelvis can anteriorly tilt the pelvis
  8. Semispinalis capitis, cervicis, and thoracis
    • -Acting bilaterally, extends spine and head
    • -Acting unilaterally, side bends spine and head to same side and rotates to opposite side
  9. Multifidus
    • -Acting bilaterally, extends the spine
    • -Acting unilaterally, side bends spine to same side and rotates to opposite side
  10. Rotatores brevis and longus
    • -Acting bilaterally, extends the spine
    • -Acting unilaterally, side bends spine to same side and rotates to opposite side
  11. Rectus capitis posterior major
    Extends and rotates head to same side
  12. Rectus capitis posterior minor
    Extends head
  13. Obliquus capitis inferior
    Rotates head to same side
  14. Obliquus capitis superior
    Extends and side bends head
  15. External intercostals
    • -Elevate ribs during inspiration
    • -Stabilize chest wall preventing the intercostal spaces from bulging in and out during respiration
  16. Internal intercostals
    • -Depress ribs during expiration
    • -Stabilize chest wall preventing the intercostal spaces from bulging in and out during respiration
  17. Innermost intercostals
    • -Depress ribs during expiration
    • -Stabilize chest wall preventing the intercostal spaces from bulging in and out during respiration
  18. Transversus thoracis
    Depresses costal cartilages during expiration
  19. Levatores costarum brevis and longus
    Elevate the ribs during inspiration
  20. Diaphragm
    respiration
  21. External abdominal oblique
    • -the 2 flat muscles (external and internal obliques and the transverses abdominis) support the abdominal viscera, compress the abdomen and play important roles in expiration, defecation, urination, parturition and vomiting
    • -when the pelvis is flexed, the recti and obliques bend the trunk forward and flex the lumbar part of the vertebral column. When the thorax is fixed, they rotate the pelvis upward (posterior tilt). If the muscles of only one side act, the trunk is bent toward that side.
    • -the external oblique of one side acts with the internal oblique of the opposite side to flex and rotate the trunk to the side of the internal oblique (ex: doing sit-up and rotating to the R involves the L external oblique and the R internal oblique)
  22. Internal abdominal oblique
    • -the 2 flat muscles (external and internal obliques and the transverses
    • abdominis) support the abdominal viscera, compress the abdomen and play
    • important roles in expiration, defecation, urination, parturition and
    • vomiting
    • -when the pelvis is flexed, the recti and obliques bend the
    • trunk forward and flex the lumbar part of the vertebral column. When
    • the thorax is fixed, they rotate the pelvis upward (posterior tilt). If
    • the muscles of only one side act, the trunk is bent toward that side.
    • -the external oblique of one side acts with the internal oblique of the
    • opposite side to flex and rotate the trunk to the side of the internal
    • oblique (ex: doing sit-up and rotating to the R involves the L external
    • oblique and the R internal oblique)
  23. Transversus abdominis
    • -the 2 flat muscles (external and internal obliques and the transverses
    • abdominis) support the abdominal viscera, compress the abdomen and play
    • important roles in expiration, defecation, urination, parturition and
    • vomiting
    • -when the pelvis is flexed, the recti and obliques bend the
    • trunk forward and flex the lumbar part of the vertebral column. When
    • the thorax is fixed, they rotate the pelvis upward (posterior tilt). If
    • the muscles of only one side act, the trunk is bent toward that side.
    • -the external oblique of one side acts with the internal oblique of the
    • opposite side to flex and rotate the trunk to the side of the internal
    • oblique (ex: doing sit-up and rotating to the R involves the L external
    • oblique and the R internal oblique)
  24. Rectus abdominis
    • -the 2 flat muscles (external and internal obliques and the transverses abdominis) support the abdominal viscera, compress the abdomen and play important roles in expiration, defecation, urination, parturition and vomiting
    • -when the pelvis is flexed, the recti and obliques bend the trunk forward and flex the lumbar part of the vertebral column. When the thorax is fixed, they rotate the pelvis upward (posterior tilt). If the muscles of only one side act, the trunk is bent toward that side.
    • -the external oblique of one side acts with the internal oblique of the opposite side to flex and rotate the trunk to the side of the internal oblique (ex: doing sit-up and rotating to the R involves the L external oblique and the R internal oblique)
  25. Quadratus lumborum
    • -side bending of lumbar spine
    • -depresses 12th rib during inspiration
    • -acting bilaterally, may assist in extension of lumbar spine
    • -unilaterally acting on pelvis, performs hip hike
Author
gcostabile
ID
48240
Card Set
Muscle actions
Description
Anatomy
Updated