Structures

  • Quadratus lumborum
  • Iliocostalis lumborum
  • Iliocostalis thoracis
  • Intertransversarii
MuscleActionOriginInsertionInnervationBlood supply
Quadratus lumborum- Depress and stabilize 12th rib
- Weak lateral flexion of trunk
- Transverse process of L5
- Iliolumbar ligament
- Iliac crest
- Transverse processes of L1-4
- Inferior border of 12th rib
- Anterior rami of T12-L4- Lumbar branch of iliolumbar artery
Iliocostalis lumborum- Extension of vertebral column
- Assist lateral flexion spine
- Postural stabilisation of spine
- Sacrum
- Spinous processes of T10-L5
- Iliac crest
- Angles of ribs 7-12- Dorsal rami T7-L3- Lumbar arteries
Iliocostalis thoracis- Extension of vertebral column
- Assist lateral flexion spine
- Postural stabilisation of spine
- Angles of ribs 7-12- Angles of ribs 1-6- Dorsal rami T7-L3- Lumbar arteries
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