Structures

  • Levatores costarum
  • Interspinales (missing from atlas)
  • Intertransversarii
MuscleActionOriginInsertionInnervationBlood supply
Levatores costarum- Contraction elevates rib- Short paired muscles arising from transverse processes of C7-T11The rib below vertebra of origin near tubercle- Dorsal rami T8-T11- Posterior intercostal arteries
Interspinales- Weak extension of spine
- Proprioception
- Short, paired muscles (one each side) attached to the spinous processes of contiguous vertebrae C2-L4(as origin describes)- Dorsal rami of C3-L4- Lumbar arteries
- Posterior intercostal arteries
- Occipital artery
Intertransversarii- Weak lateral flexion of spine
- Proprioception
- Small muscles between the transverse processes of contiguous vertebrae C1-C7; T9-12;L1-5(as origin describes)- Posterior rami of spinal nerves- Lumbar arteries
- Posterior intercostal arteries
- Occipital artery