Deep back / Posterior abdominal wall
Quadratus lumborum
Laterally flexes and extends the trunk and stabilizes the twelfth rib during breathing
- Origin
- Posterior iliac crest and iliolumbar ligament
- Insertion
- Twelfth rib and transverse processes of the upper lumbar vertebrae
- Primary actions
- Laterally flexes and extends the trunk and stabilizes the twelfth rib during breathing
Anatomy reference
OpenStax Anatomy and Physiology 2e — Axial Muscles of the Abdominal Wall and Thorax
Open referenceEducational anatomy reference only. This page does not diagnose pain, injury, or movement limitations.
From anatomy to action
Explore the movement, not just the muscle.
A single muscle rarely explains a movement by itself. Use the related movement content to see how this anatomy may contribute, then choose a focused program when you want a complete progression.
Corrective movement strategies and exercises
Mobility focus
Excessive Anterior Pelvic Tilt
Explore pelvic and trunk-control options without treating pelvic angle as a diagnosis or forcing a neutral position.
Open corrective movement strategy
Mobility focus
Asymmetric Hip Shift
Explore comfortable left-to-right loading options during standing, squatting, stepping, and walking.
Open corrective movement strategy