Posterior abominal muscles

Question 1

what forms the posterior abdominal wall

Answer 1

the lumbar vertebrae, pelvic girdle, posterior abdominal muscles and their associated fascia

Question 2

where are the Major vessels, nerves and organs are located

Answer 2

on the inner surface of the posterior abdominal wall.

Question 3

what are 5 muscles in the posterior abdominal wall

Answer 3

iliacus, psoas major, psoas minor, quadratus lumborum and the diaphragm

Question 4

Where is the quadratus lumborum and shape

Answer 4

The quadratus lumborum muscle is located laterally in the posterior abdominal wall. It is a thick muscular sheet which is quadrilateral in shape. The muscle is positioned superficially to the psoas major.

Question 5

attachments of Quadratus Lumborum attachments

Answer 5

It originates from the iliac crest and iliolumbar ligament. The fibres travel superomedially, inserting onto the transverse processes of L1 – L4 and the inferior border of the 12th rib.

Question 6

attachments of Quadratus Lumborum actions

Answer 6

Extension and lateral flexion of the vertebral column. It also fixes the 12th rib during inspiration, so that the contraction of diaphragm is not wasted.

Question 7

attachments of Quadratus Lumborum and innetvation

Answer 7

Anterior rami of T12- L4 nerves.

Question 8

where is the Psoas major?

Answer 8

The psoas major is located near the midline of the posterior abdominal wall, immediately lateral to the lumbar vertebrae.

Question 9

attachments of Psoas major

Answer 9

Originates from the transverse processes and vertebral bodies of T12 – L5. It then moves inferiorly and laterally, running deep to the inguinal ligament, and attaching to the lesser trochanter of the femur.

Question 10

actions of Psoas major

Answer 10

Flexion of the thigh at the hip and lateral flexion of the vertebral column.

Question 11

innervation of the Psoas major

Answer 11

Anterior rami of L1 – L3 nerves.

Question 12

describe the structure and location of the iliacus

Answer 12

The iliacus muscle is a fan-shaped muscle that is situated inferiorly on the posterior abdominal wall. It combines with the psoas major to form the iliopsoas – the major flexor of the thigh.

Question 13

desribe the attachments of the iliacus

Answer 13

Attachments: Originates from surface of the iliac fossa and anterior inferior iliac spine. Its fibres combine with the tendon of the psoas major, inserting into the lesser trochanter of the femur.

Question 14

desribe the attachments of the iliacus

Answer 14

Actions: Flexion of the thigh at the hip joint.

Question 15

desribe the innevation of the iliacus

Answer 15

Femoral nerve (L2 – L4).

Question 16

which part of the diaphraph is a lpart of tthe posterior abdominal wall?

Answer 16

The posterior aspect of the diaphragm is considered to be part of the posterior abdominal wall

Question 17

what lies between the parietal peritoneum and the muscles of te posterior abdominal wall

Answer 17

a layer of facisa

Question 18

which muscel of the anterolateral abdominal wall is the facisa continuos with?

Answer 18

the transversalis fascia

Question 19

what are the diffeerent names for the facisa?

Answer 19

Psoas Fascia

Thoracolumbar facisa

Question 20

what does the psoas fascia cover and what is it attach to

Answer 20

The psoas fascia covers the psoas major muscle. It is attached to the lumbar vertebrae medially, continuous with the thoracolumbar fascia laterally and continuous with the iliac fascia inferiorly

Question 21

what are the three layers of the thoracolumbar fascia?

Answer 21

posterior, middle and anterior

Question 22

which muscles are enclosed in teh 3layers of the thoracolumr facisa?

Answer 22

Quadratus lumborum – between the anterior and middle layers.

Deep back muscles – between the middle and posterior layers.

Question 23

desribe the anatomy of the posterior layer of the thoracolumbar facisa

Answer 23

The posterior layer extends between the 12th rib and the iliac crest posteriorly. Laterally the fascia meets the internal oblique and transversus abdominis muscles, but not the external oblique. As it forms these attachments it covers the latissimus dorsi.

Question 24

desribe the anatomy of the anterior layer of the thoracolumbar facisa

Answer 24

The anterior layer attaches to the anterior aspect of the transverse processes of the lumbar vertebrae, the 12th rib and the iliac crest. Laterally the fascia is continuous with the aponeurotic origin of the transversus abdominis muscle. Superiorly the fascia thickens to become the lateral arcuate ligament, which joins the iliolumbar ligaments inferiorly.

Question 25

innervation of the diaphragm?

Answer 25

The halves of the diaphragm receives motor innervation from a phrenic nerve. The left half of the diaphragm (known as a hemidiaphragm) is innervated by the left phrenic nerve, and vice versa. Each phrenic nerve is formed in the neck within the cervical plexus, and contains fibres from spinal roots C3-C5.

Question 26

the arterial supply of the diaphragm

Answer 26

The majority of the arterial supply to the diaphragm is delivered via the inferior phrenic arteries, which arise directly from the abdominal aorta. The remaining supply is from the superior phrenic, pericardiacophrenic, and musculophrenic arteries

Question 27

veinous drainage of the diaphragm

Answer 27

The draining veins follow the aforementioned arteries.he inferior phrenic arteries, which arise directly from the abdominal aorta. The remaining supply is from the superior phrenic, pericardiacophrenic, and musculophrenic arteries

Question 28

what happens during inspirtation to the diaphragm

Answer 28

it contracts and flattens, increasing the vertical diameter of the thoracic cavity. This produces lung expansion, and air is drawn in.

Question 29

what happens during expirtation to the diaphragm

Answer 29

During expiration, the diaphragm passively relaxes and returns to its original dome shape. This reduces the volume of the thoracic cavity. and air is drawwn out

Question 30

which posteiral abdominal muscle is also a primary muscle of respiration

Answer 30

diaphragm

Question 31

what are the 3 diaphraphm hiatus’ and what passes though?

Answer 31

Oesophageal opening (T10 level): Transmits the oesophagus, vagus nerves, and oesophageal branches of the left gastric vessels.
Aortic opening (T12 level): Transmits the aorta, thoracic duct (a large lymphatic vessel) and azygous vein.
Caval opening (T8 level): Transmits the inferior vena cava.

Question 32

location of the diapham

Answer 32

the inferior-most aspect of the ribcage, filling the inferior thoracic aperture

Question 33

The attachments of diaphragm can be divided into peripheral and central attachments, what are the three peripheral attachments?

Answer 33

Lumbar vertebrae and arcuate ligaments.
Costal cartilages of ribs 7-10 (attach directly to ribs 11-12).
Xiphoid process of the sternum.

Question 34

what are the left and right crus

Answer 34

The parts of the diaphragm that arise from the vertebrae are tendinous in structur

Question 35

where deoes the Left crus arise from?

Answer 35

Arises from L1-L2 and their intervertebral discs.

Question 36

where does the right crus arise from

Answer 36

– Arises from L1-L3 and their intervertebral discs.

Question 37

what do some fribres of the right crus do and wh?y

Answer 37

. Some fibres from the right crus surround the oesophageal opening, acting as a physiological sphincter to prevent reflux of gastric contents into the oesophagus.

Question 38

what is the central tendon formed by

Answer 38

the combined fibres of the diaphragm

Question 39

what does the central tendo ascend to fuse with?

Answer 39

fibrous pericardium

Question 40

what happens either side of the pericardium to the diapham structurally

Answer 40

the diaphragm ascends to form left and right domes.

Question 41

at rest which dome is higher

Answer 41

the right, maybe becuase of liver

Question 42

two main functions of the diahm

Answer 42

separates the thoracic cavity from the abdominal cavity (the word diaphragm is derived from the Greek ‘diáphragma’, meaning partition).
Undergoes contraction and relaxation, altering the volume of the thoracic cavity and the lungs, producing inspiration and expiration.