quadratus lumborum muscle

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quadratus lumborum

An abdominal muscle located at the iliac crest, iliolumbar ligaments, transverse processes of lower lumbar vertebrae.

Abduction of trunk.
Ventral branches of upper lumbar spinal nerves.

12th rib, transverse processes of upper lumbar vertebrae.

quad·ra·tus lum·bo·rum mus·cle

(kwah-drā'tŭs lŭm-bō'rŭm mŭs'ĕl)
Origin, iliac crest, iliolumbar ligament, and transverse processes of lower lumbar vertebrae; insertion, twelfth rib and transverse processes of upper lumbar vertebrae; action, abducts trunk; nerve supply, ventral primary rami of upper lumbar spinal nerves.
Synonym(s): musculus quadratus lumborum [TA] .
References in periodicals archive ?
Low back pain is most often associated with quadratus lumborum muscle Trigger Points (TPs), often with an accompanying lumbar multifidi and superficial paraspinal muscle TPs.
When she puts her leg on the barre, she keeps it no higher than 90 degrees and adds in a side cambre to get at her quadratus lumborum muscle in her lower back which sometimes gets tight.
The lesion also involved the right quadratus lumborum muscle and the right erector spinae muscle [Figure 1]b.
Hypertonicity was also noted within the right quadratus lumborum muscle.
1] However, in a mathematical model used to estimate lumbar spinal stresses during quadratus lumborum muscle asymmetry, it was suggested that quadratus lumborum muscle asymmetry only causes small stresses and it may even help to reduce stress on the lumbar spine.
This can be accomplished by hiking the contralateral hip by contracting the quadratus lumborum muscle.
Furthermore the iliolumbar ligament is closely associated with the lower attachments of the anterior and middle layers of the thoracolumbar fascia and the quadratus lumborum muscle (Bogduk 1997; Frazer 1940; Fujiwara et al.
11,13) The lateral arcuate ligament of the diaphragm has a similar attachment with the quadratus lumborum muscle.
These are made up of several muscle groups: The "abs" at the front of your abdomen; the internal and external obliques in the front and sides of the abdomen; the transversus muscles that run horizontally across your lower abdomen, the erector spinae (the large muscles on either side of your spinal core), the scapulae (the muscles that surround your shoulder blades), the gluteus muscles in your hips and buttocks, and the iliopsoas and quadratus lumborum muscles in your pelvis.
It is concluded that in classical ballet dancers LBP and hip-region pain are associated with a smaller CSA of the multifidus but not the erector spinae, psoas, or quadratus lumborum muscles.
Soft tissue palpation revealed tight and tender bilateral gluteal, tensor fascia latta, iliopsoas, piriformis (more left than right sided), hamstrings, gastrocnemius, first metatarsal plantar flexors, lumbar erector spinae and quadratus lumborum muscles.