The quadratus lumborum muscle is a common muscle involved in lower back pain.

Origin

  • Posterior iliac crest
  • Iliolumbar ligament

Insertion

  • Twelfth rib
  • Transerve processes of L1-L4

Actions

  • Laterally flexes (side-bends) trunk

Innervation

  • Ventral rami of the subcostal nerve
  • Lumbar nerves

Daily uses

  • Bending sideways to pick something up

Example strengthening exercises

  • Side-bends

Example stretches

  • Side stretch

Neck and Back Muscles:

More Human Muscles: