Lumbar region

Question 1

What movements are available at the lumbar spine?

Answer 1

Flexion, extension, rotation, lateral flexion.
FLEXION is greater than extension and there’s more movement in the lower segments.
SIDE FLEXION is couples with rotation.
ROTATION is 1 degree at each segmental level with less rotation available at L5-S1 and a mean rotation of 8-12 degrees in each direction. Limited by facet joints.

Question 2

What are the layers of the thoracolumbar fascia?

Answer 2

Posterior layer - superficial to the erector spinae and attached to the spinous processes.
Middle layer - between erector spinae and quadratus lumborum, attached to transverse tips.
Anterior layer - deep to quadratus lumborum, attached to anterior of transverse processes.

Question 3

External Obliques

Answer 3

Origin: Outer surfaces of lower 8 ribs
Insertion: Linea alba, lateral lip of iliac crest
Action: Flexes trunk, ipsilateral side flexion, contralateral rotation, compresses abdominal contents
Nerve Supply: Anterior rami of T7-T12

Question 4

Internal Obliques

Answer 4

Origin: Thoracolumbar fascia, lateral 2/3 of inguinal ligament, iliac crest
Insertion: Inf. border of lower 3 or 4 ribs, linea alba, pubic crest and pectineal line
Action: Flexes trunk, ipsilateral side flexion and rotation, compresses abdominal content.
Nerve Supply: Anterior rami of T7-T12 and L1.

Question 5

Transverse Abdominus

Answer 5

Origin: Thoracolumbar fascia, medial lip of iliac crest, lateral 1/3 of inguinal ligament, CCs lower 6 ribs.
Insertion: Linea alba, pubic crest and pectineal line.
Actions: Compress abdominal contents but this is also a stability muscle.
Nerve Supply: Anterior rami of T7-T12 and L1

Question 6

Rectus Abdominus

Answer 6

Origin: Pubic crest, pubic tubercle, pubic symphysis
Insertion: CCs of ribs 5 to 7, xiphoid process
Actions: Compress abdominal contents, flex trunk, tense abdominal wall
Nerve Supply: Anterior rami of T7-T12

Question 7

What are the functions of the abdominals?

Answer 7

Trunk movement, sitting up from lying, getting out of bed, protection of the abdominal viscera, spinal stabilisation, abdominal pressure for (forced expiration, micturition, defecation, parturition, vomiting)

Question 8

What are the layers of the rectus sheath?

Answer 8

Anterior layer: External obliques, internal obliques
Posterior layer: Internal obliques, transverse abdominus
MIDLINE IS LINEA ALBA

Question 9

Quadratus Lumborum

Answer 9

Origin: Post border of iliac crest, iliolumbar ligament
Insertion: Inferior border of 12th rib and Tps L1-L5.
Actions: Muscle of inspiration, ipsilateral side flexion, lumbar extension
Nerve Supply: Anterior rami of T12-L4

Question 10

Erector Spinae

Answer 10

ILIOCOSTALIS (most lateral) -
LONGISSIMUS
SPINALIS
Actions: Bilateral extension (controls flexion), lumbar lordosis, unilateral ipsilateral lateral flexion/rotation.
Nerve Supply: Posterior rami of adjacent thoracolumbar nerves.

Question 11

Semispinalis (Thoracics) {Stability}

Answer 11

Origin: TP of thoracic 6-10
Insertion: SP of upper 4 thoracic & lower 2 cervical vertebrae

Question 12

What other muscles contribute to the stability of the lumbar spine?

Answer 12

Multifidus, Interspinales, Rotatores, Intertransversus
(rotatores is best developed and deepest in the thoracic region)

Question 13

Ant/Post longitudinal ligaments

Answer 13

Long ligaments that run along the length of the vertebral column, covers vertebral bodies & intervertebral discs. Anterior limits extension, posterior limits flexion

Question 14

Ligamentum flavum

Answer 14

Short but thick ligament connects laminae of adjacent vertebrae from C2 to S1. In the neck they are thin and long, thicker in thoracic region and thickest in lumbar region. Mainly helps to limit flexion of lumbar spine.

Question 15

Supraspinous ligament

Answer 15

Originates from C7 and inserts in sacrum. Limits flexion.

Question 16

Interspinous ligament

Answer 16

Anteriorly connects with ligamentum flavum, posteriorly connects with supraspinous ligament. Narrow & elongated in thoracic region, broader thicker and quadrilateral in lumbar. Only slightly developed in neck (part of nuchal lig). LIMITS FLEXION

Question 17

Intertransverse ligament

Answer 17

Between TP. In cervical region they consist of a few scattered irregular fibres often replaced by muscles. In thoracic region they are rounded cords intimately connected with deep muscles of back. In lumbar they are thin and membranous. Often blend with intertransverse muscles. LIMITS LATERAL FLEXION OF SPINE AND TRUNK.

Question 18

Joints of the lumbar spine

Answer 18

Facet joints - synovial plane
Intervertebral joints - facet joint. Inf. articular process of sup. vertebrae articulates with sup. articular process of inf. vertebrae.