Lumbar Spine: Movement And Muscles

Question 1

Movements of lumbar spine

Answer 1

Flexion, extension, rotation, lateral flexion

Question 2

Muscles of the anterolateral abdominal wall

Answer 2

Rectus abdominis, external oblique, internal oblique, transversus abdominis, fascia- rectus sheaf

Question 3

Muscles of posterior abdominal wall

Answer 3

Psoas major, iliacus, quadratus lumborum, fascia- thoracolumbar fascia

Question 4

Muscles of thoracolumbar fascia

Answer 4

Post layer- superficial to erector spinae and attached to spinous processes
Mid layer- between erector spinae and quadratus lumborum attached to transverse tips
Anterior layer- deep to quadratus lumborum attached to anterior of transverse processes

Question 5

Origins, insertions, actions and nerve supply of external oblique

Answer 5

Origins: outer surface of 5-12th rib and costalncartilages
Insertions: linea alba via rectus sheaf, pubic tubercles to ASIS (inguinal ligament) anterior 2/3 iliac crest
Actions: flexion of trunk, posterior pelvic tilt, contra lateral rotation (trunk on pelvis) lateral flexion
Nerve supply: anterior rami of T7- T12

Question 6

Origins, insertions, actions and nerve supply of internal oblique

Answer 6

Origins: lower border of 10-12 th ribs, linea Alba via rectus sheaf, pectin pubis (conjoint tendon)
Insertions: latéral 2/3:of inguinal ligament, anterior 2/3 of iliac crest, thoracolumbar fascia
Actions: posterior pelvic tilt, flexion, ipsilateral rotation (trunk on pelvis)
Nerve supply: L1 nerve, anterior rami of T7- T12

Question 7

Origins, insertions, actions and nerve supply of transversus abdominis

Answer 7

Origins: internal surfaces of 7-12th costal cartilages, thoracolumbar fascia, iliac crest, lat 1/3 of inguinal ligament
Insertions: linea alba via rectus sheaf, pectin pubis (conjoint tendon)
Action: raises abdominal pressure, stabilising muscle of lumbar spine
Nerve supply: L1 nerve, anterior rami of T7-T12

Question 8

Origins, insertions, actions and nerve supply of rectus abdominis

Answer 8

Origin: xiphoïde process, 5-7th costal cartilages
Insertion: pubic symphysis, pubic crest
Action: flexion of trunk, contralateral rotation and ipsilateral lateral flexion of trunk, posterior pelvic rotation
Nerve supply: anterior rami of T6-T12

Question 9

Origins, insertions, actions and nerve supply of quadratus lumborum

Answer 9

Origins: medial 1/2 lower border of 12th rib
Insertions: TPs lumbar vertebrae, iliolumbar ligament, iliac crest
Actions: muscle of inspiration, ipsilateral side flexion, lumbar extension (both acting)
Nerve supply: ventral roots T12-L4

Question 10

Describe Erector spinae lumbar

Answer 10

Lumbar spine- iliocostalis lumbroum from iliac region attaching to posterior rib angles, powerful extensor of lumbar and throacic spine works bilaterally as a side flexor

Question 11

Origins, insertions, action and nerve supply of erector spinae

Answer 11

Origin:lower 6 rib angles
Insertions: T11-L5 spinous processes, supraspinous/ sacro iliac ligaments, sacral crests, post part of iliac crest, iliac tuberosity , inner lip of iliac crest and thoracolumbar fascia
Action: bilateral extension, control of flexion maintenance of lumbar lordosis, unilateral ipsilateral/ lateral flexion/ rotation
Nerve supply: dorsal rami or adjacent thoracolumbar nerve

Question 12

Origin, insertions, action and nerve supply of semispinalis (don’t need to know)

Answer 12

Origins- TP T6-T10
Insertions- lower cervical/ upper thoracic spinous processes
Action- bilateral extension CSp and TSp, unilateral may assist rotation but not a key role
Nerve supply

Question 13

Origin, insertion, of multifidus (only need to know name and action)

Answer 13

Origin (lumbar spine: post sacrum, Mammillary process, lumbar vertebrae (sup, art, facet) dorsal sacral iliac ligament, PSIS
Insertions: 3 layers, spinous process above dependent on layer, deepest-1, middle 2/3, superficial 3/4
ACTION: IMPORTANT STABILISER OF LUMBAR SPINE
FUNCTION: TOGETHER WITH TRANSVERSUS ABDOMINIS AND PELVIC FLOOR MUSCLES