Last update:

Quadratus Lumborum Muscle

image descriptionQuadratus Lumborum:

Unlabelled image of the muscles of the back.
Labelled image of the sternocleidomastoid, splenius capitis, splenius cervicis, external intercostals, and quadratus lumborum muscles as well as the iliocostalis, longissimus, and spinalis muscle groups.
Labelled image of the iliocostalis, longissimus, spinalis muscle groups, and the quadratus lumborum
Labelled image of the longissimus, spinalis muscle group, and quadratus lumborum muscle.
Labelled image of the spinalis muscle group, and quadratus lumborum muscle.
Labelled image of the semispinalis capitis, semispinalis thoracis, multifidus, and quadratus lumborum muscles
Labelled image of the multifidus, and quadratus lumborum muscles.
Labelled image of the quadratus lumborum muscle.
Muscularis Quadratus Lumborum
1
2
3
4
5
6
7
8

image descriptionAttachments of the Quadratus Lumborum:  Origin & Insertion

Origin: Medial half of the posterior iliac crest and iliolumbar ligament.

Insertion: Transverse processes of L1-L4 and medial half of 12th rib.

Unlabelled image of the muscles of the back.
Labelled image of the insertion and origin of the quadratus lumborum.
Origin and insertion of the quadratus lumborum.
1
2

Actions of the Quadratus Lumborum Muscle:

  1. Bilateral action: image descriptionextends vertebral column; stabilizes 12th rib while breathing.
Extensions of the vertebral column animation slide 1
Extensions of the vertebral column animation slide 2
Extensions of the vertebral column animation slide 3
Extensions of the vertebral column animation slide 4
Extension of the vertebral column.
  1. Ipsilateral action: image descriptionlaterally flexes vertebral column.
Lateral flexion of the vertebral column animation slide 1
Lateral flexion of the vertebral column animation slide 2
Lateral flexion of the vertebral column animation slide 3
Lateral flexion of the vertebral column animation slide 4
Lateral flexion of the vertebral column animation slide 5
Lateral flexion of the vertebral column.

Nerve Supply to Quadratus Lumborum:

  1. Subcostal nerve (thoracic; T12) and ventral rami of lumbar spinal nerves (L1-L4).

Overview of the Muscles of the Back:

Test yourself image answers hidden.
Test yourself image showing answers: trapezius, deltoid, latissimus dorsi
Test yourself image showing answers: supraspinatus, infraspinatus, teres minor, teres major
Test yourself image showing answers: levetor scapula, rhomboids minor, rhomboids major, serratus anterior
Test yourself image showing answers: serratus anterior superior, serratus posterior inferior
Test yourself image showing answers: Sternocleidomastoid, splenius capitis, splenius cervicis, external intercostals, iliocostalis group, longissimus group, quadratus lumborum, spinalis group
Test yourself image showing answers: Iliocostalis group, Longissimus group, spinalis group, quadratus lumborum
Test yourself image showing answers: Longissimus group, Spinalis group, Quadratus lumborum
Test yourself image showing answers: Spinalis group, quadratus lumborum
Test yourself image showing answers: semispinalis capitis, semispinalis thoracis, multifidus, quadratus lumborum
Test yourself image showing answers: multifidus, quadratus lumborum
Test yourself image showing answers: quadratus lumborum
Test yourself image showing answers: insertion and origin
Review the muscles of the back and test yourself.
1
2
3
4
5
6
7
8
9
10
11
12
13