Quadratus Lumborum (“QL”)

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• Use of this artwork requires proper credit to be given (Permission: Dr. Joe Muscolino. www.learnmuscles.com – art work Giovanni Rimasti)

ATTACHMENTS:

• The quadratus lumborum attaches from the inferomedial border of the 12th rib and the transverse processes of L1-L4 to the posteromedial iliac crest.

ACTIONS:

• The quadratus lumborum elevates the same-side pelvis and anteriorly tilts the pelvis at the lumbosacral joint.
• It extends and laterally flexes the trunk at the spinal joints.
• It also depresses the 12th rib at the costovertebral joint.