Muscles of the head trunk and pelvis

  1. Sternocleidomastoid (SCM)
    • O: Sternal head: anterior surface of manubrium
    • Clavicular head: superior surface of medial third of clavicle. 
    • I: Mastoid process of temporal bone and superior nuchal line of occipital bone.
  2. SCM action
    • Acting unilaterally, laterally flexes and rotates the head and neck so the ear approaches the shoulder of the same side. 
    • Acting bilaterally, flex the neck.
  3. Superficial layer of the back muslces
    Splenius muscles
  4. Origin of splenius
    Nuchal ligament and spinous processes of C7 - T3 or T4 vertebrae
  5. Insertion of splenius capitis
    Mastoid process of temporal bone and lateral third of superior nuchal line of occipital bone
  6. Insertion of splenius cervicis
    Transverse process of C1-C3 or C4 vertebrae
  7. Intermediate layer of the back muscles
    Erector spinae (Sacrospinalis)
  8. Common origin of the erector spinae muscles
    Broad tendon from posterior part of iliac crest, posterior surface of sacrum, sacral and inferior lumbar spinous processes, and supro-iliac ligament.
  9. Iliocostalis insertion
    Fibers run superiorly to ribs and cervical transverse processes.
  10. Longissimus insertion
    To ribs between tubercles and angles, to transverse processes in thoracic and cervical regions, and to mastoid process of temporal bone.
  11. Insertion of spinalis
    To spinous processes in the upper thoracic region and to skull.
  12. Deep layer of back muscle
    • Transverso-spinal muscle group: 
    • Semispinalis - Superficial
    • multifidus - deeper
    • rotatores - deepest
  13. Semispinalis origin
    Transverse process of C4 - T12
  14. Semispinalis insertion
    superomedially to occipital bone and spinous processes in thoracic and cervical regions, spanning 4 - 6 segments.
  15. Semispinalis main action
    Extend head, thoracic and cervical regions of vertebral column and rotate them contralaterally.
  16. Multifidus origin
    Posterior aspects of sacrum and ilium, transverse processes of thoracic and lumbar vertebrae, and articular processes of the C4 - C7
  17. Multifidus insertion
    Superomedially to entire length of spinous processed of vertebrae above, spannin 2 - 4 segments
  18. Multifidus main action
    Stabilizes vertebrae during local movements of vertebral column. Unilateral contraction rotates to contralateral side.
  19. Rotatores origin
    Transverse processes of vertebrae
  20. Rotatores insertion
    Pass superomedially to attach to the root of the spinous processes of the next one or two vertebrae superiorly, spanning 1 - 2 segments
  21. Rotatores main action
    Proprioception organs. Stabilize vertebrae and assists with local extension and rotary movements of vertebral column.
  22. Which 3 muscles form the Minor Deep Layer of the back.
    Interspinal, intertransverse, levatores costarum.
  23. Muscles in the thoracic wall
    External intercostals (superior layer)Internal intercostals (middle layer)Innermost intercostals (deepest layer)
  24. Muscles in the thoracic wall superior attachment
    Inferior border of ribs
  25. Muscles in the thoracic wall inferior attachment
    Superior border of ribs below
  26. Muscles in the thoracic wall main action
    Elevate ribs: external intercostals and probably innermost intercostalsDepress ribs: Internal intercostals
  27. External Oblique origin
    External surface of 5th-12th ribs.
  28. External Oblique insertion
    Linea alba pubic tubercle, and anterior half of iliac crest.
  29. External Oblique main action
    Compress and support abdominal viscera, flex and rotates trunk.
  30. Internal oblique origin
    Thoracolumbar fascia, anterior two-thirds of iliac crest and lateral half of inquinal ligament.
  31. Internal oblique insertion
    Inferior borders of 10-12 ribs, linea alba, and pubis via conjoint tendon.
  32. Internal oblique main action
    Compress and support abdominal viscera. Flex and rotate trunk.
  33. Innermost of the three flat abdominal muscles.
    Transverse abdominal
  34. Transverse abdominal origin
    Internal surface of 7-12 costal cartilages, thoracolumbar fascia, iliac crest, and lateral third of inquinal ligament.
  35. Transverse abdominal insertion
    Linea alba with aponeurosis of internal oblique, superior ramus of pubis
  36. Transverse abdominal main action
    Compress and support abdominal viscera
  37. Rectus abdominis origin
    Pubic symphysis and pubic crest
  38. Rectus abdominis insertion
    Xiphoid process and 5-7 costal cartilages.
  39. Rectus abdominis main action
    Flex trunk, compress abdominal viscera, and stabilizes and controls tilt of pelvis.
  40. Muscles of the posterior abdominal wall
    Quadratus lumborum
  41. Quadratus lumborum origin
    Medial half of inferior border of 12th rib and tips of lumbar transverse processes
  42. Quadratus lumborum insertion
    Iliolumbar ligament and iliac crest
  43. Quadratus lumborum main action
    Extends and laterally flexes v.column; fixes 12th rib during respiration.
Card Set
Muscles of the head trunk and pelvis
origin and insertion of Muscles of the head trunk and pelvis