Quadratus Lumborum

By Christy Cael
[Functional Anatomy]

Quadratus lumborum is a deep, multifunctional muscle of the spine. It connects the ilium to the lateral lumbar spine and 12th rib.

The fibers of quadratus lumborum run slightly diagonal from the rib and spine inferiorly and laterally toward the posterior ilia. Quadratus lumborum lies deep to the latissimus dorsi and erector spinae muscles and posterior to the psoas major, helping form the posterior abdominal wall.

Functionally, the quadratus lumborum muscles help position the spine relative to the pelvis when the lower body is fixed. It maintains upright posture, creating fine lateral movements and extension when coordinating with the erector spinae muscles. When we stand, the paired quadratus lumborum muscles work with the gluteus medius muscles to position the body over the lower extremities.

During walking, quadratus lumborum and gluteus medius help stabilize the pelvis as the weight of the body shifts onto one foot, then the other. These muscles prevent the pelvis from shifting laterally, directing movement forward rather than side to side. Also, quadratus lumborum raises the pelvis toward the rib cage as weight shifts to the opposite foot. This action allows the leg to swing forward without the foot hitting the ground.

Quadratus lumborum is one of several muscles that assists with breathing. During inhalation, it tethers the 12th rib inferiorly, allowing the rib cage to fully expand. Dysfunction in quadratus lumborum may result from labored breathing, weakness in gluteus medius, or imbalances in postural muscles, such as the erector spinae, abdominals, and psoas. Tightness in this muscle contributes to excessive lumbar lordosis and anterior pelvic tilt.

Palpating Quadratus Lumborum

Positioning: client prone

1. Stand at the client’s side facing the spine.

2. Locate the lumbar spinous processes with the fingertips of both your hands.

3. Slide your fingertips laterally to the opposite side, past the lamina groove and the erector spinae muscles.

4. Hook your fingers slightly, pulling the erectors back toward the spine, as you palpate deeply between the 12th rib and ilium to find the angled fibers of quadratus lumborum.

5. Instruct client to gently elevate the hip superiorly to assure proper location.


Christy Cael is a nationally certified massage therapist, certified athletic trainer, and certified strength and conditioning specialist. Her private practice focuses on injury treatment, biomechanical analysis, craniosacral therapy, and massage for clients with neurological issues. She is the author of Functional Anatomy: Kinesiology and Palpation for Manual Therapists (Lippincott Williams & Wilkins, 2009), scheduled for release in October. Contact her at functionalbook@hotmail.com.



Quadratus Lumborum
• Origin: posterior iliac crest and iliolumbar ligament

Insertion: transverse processes of L1–4 and inferior border of 12th rib


• Extends the vertebral column (bilateral action)

• Laterally flexes the vertebral column (unilateral action)

• Depresses/fixes the last rib during inhalation.


• T12–L3

• Lumbar plexus



Client Homework—Stretching

Positioning: seated
or standing
1. Sit or stand straight with your head centered over your shoulders.

2. Reach one or both of your arms straight up, lengthening your body as you take a deep breath.

3. As you exhale, continue reaching upward and tip your body to one side.


4. Reach and tip until you feel a slight stretch on the side of your trunk.


5. Take several deep breaths, increasing the reaching and tipping on each exhale. Repeat as necess