Posterior Abdominal Wall & Lumbar Plexus Flashcards

1
Q

The posterior abdominal wall is formed by…

A

…the lumbar vertebrae

  • pelvic girdle
  • posterior abdominal muscles and their associated fascia.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Superior boundary of the posterior abdominal wall

A

12th rib articulating with T12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Inferior boundary of the posterior abdominal wall

A

The Iliac crest of hip bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Posterior border of the PAW

A
  • bodies of and intervertebral discs T12-L5
  • anterior longitudinal ligament, anterior to and attached to the borders of the vertebrae
  • crura of the diaphragm (right crus - L1-L3 vertebral bodies, left crus - L1-L2 vertebral bodies)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The right and left crus of the PAW are joined by…

A

…the median arcuate ligament

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The right crus of the diaphragm is longer than the left. True or false?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Muscles of the PAW

A

Psoas major
Psoas minor
Iliacus
Quadratus lumborum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Shape of psoas major

A

Fusiform

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Origin of psoas major

A

Anterior surface and lower borders of the transverse processes of L1-L4 vertebrae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How many slips make up psoas major?

A

5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The slips of psoas major arise from

A

the bodies of adjacent vertebrae and intervertebral discs from T12- L5 vertebrae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The slips of psoas major are joined by…

A

Tendinous arches

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Psoas major passes in front of the inguinal ligament into the front of the thigh. True or false?

A

False. It goes behind it.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Insertion of psoas major

A

The tip and medial part of the lesser trochanter of femur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Nerve supply of psoas major

A

Direct branches L2,3,4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

In what percentage of the population is there Psoas minor?

A

60%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Psoas minor lies

A

On the anterior surface of the Psoas major

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Origin of psoas minor

A

The fascia covering psoas major, Iliacus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Psoas minor inserts into…

A

…the pectineal line and iliopubic eminence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Origin of iliacus

A
  • Upper 2/3 of Iliac fossa
  • Inner lip of Iliac crest
  • Upper surface of lateral part of the sacrum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Insertion of iliacus

A

Inserts with psoas major into lesser trochanter

22
Q

Action of psoas major

A

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

23
Q

Action of iliacus

A

Flexion of the thigh and lateral rotation of the hip

24
Q

Action of psoas minor

A

Flexion of the vertebral column.

25
Q

Innervation of iliacus

A

Femoral nerve L2 to L4

26
Q

The fascia of the PAW is one continuous sheet. True or false?

A

True

27
Q

The thoracolumbar fascia encloses which muscles?

A

Quadratus lumborum

Deep back muscles

28
Q

Origin of quadratus lumborum

A

It originates from the iliac crest and iliolumbar ligament.

29
Q

Insertion of quadratus lumborum

A

The transverse processes of L1 – L4 and the inferior border of the 12th rib

30
Q

Psoas muscle is enclosed in the psoas sheath. True or false?

A

True

31
Q

The lumbar plexus is formed by…

A
  • the ventral rami of the 1st three lumbar nerves
  • part of the 4th
  • a twig from the subcostal nerve.
32
Q

The 1st ramus is joined by

A

a branch of the 12th thoracic nerve.

33
Q

What forms the lumbosacral trunk?

A

The lower half of the 4th ramus and the 5th ramus

34
Q

The lumbar plexus is formed where?

A

In the substance of the psoas muscle

35
Q

The largest and most important branches of the lumbar plexus are:

A

the femoral and obturator nerves

36
Q

The obturator and femoral nerves spring from what parts of the lumbar plexus?

A

The segments L 2,3 and 4

37
Q

What are the branches of the lumbar plexus?

A
Obturator Nerve
Femoral Nerve
Genitofemoral Nerve Iliohypogastric Nerve
Ilioinguinal Nerve
Lateral Cutaneous Nerve of Thigh
38
Q

Direction of the obturator nerve

A
  • Appears from the medial side of the psoas.
  • Pierces psoas fascia
  • Crosses the sacro-iliac joint
  • Passes lateral to the int. iliac vessels and ureter and enters pelvis cavity.
39
Q

The obturator nerve runs to…

A

… the upper part of the obturator foramen.

40
Q

Direction of the femoral nerve

A
  • Enters thigh behind inguinal ligament
  • Appears at the lateral border of the psoas
  • Runs down between psoas and iliacus
  • Supplies iliacus within the false pelvis
41
Q

The femoral nerve lies lateral to the femoral sheath and does not enter it. True or false?

A

True

42
Q

The nerves of the lumbar plexus appear…

A

at the lateral border of the psoas.

43
Q

The lateral femoral cutaneous nerve arises from…

A

L2,3

44
Q

The iliohypogastric and ilioinguinal nerves enter the abdomen in front of the medial arcuate ligament. True or false?

A

False. It’s behind it.

45
Q

The iliohypogastric and ilioinguinal nerves pierce the transversus, internal oblique and external oblique aponeurosis. True or false?

A

True

46
Q

Which nerves supply the skin of suprapubic and inguinal regions?

A

The iliohypogastric and ilioinguinal nerves

47
Q

The subcostal nerve is part of the lumbar plexus. True or false?

A

False

48
Q

The genitofemoral nerve divides into…

A

2 branches: femoral and genital which descend in front of the psoas muscle.

49
Q

The femoral branch of genitofemoral nerve supplies

A

the skin of the femoral triangle and pierces the fascia lata

50
Q

The genital branch of the genitofemoral nerve supplies…

A

…the cremaster muscle and the skin of the scrotum

51
Q

The genital branch of the genitofemoral nerve does not go through the inguinal canal but it pierces the coverings of the spermatic cord. True or false?

A

False, it does.