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Flashcards in Anatomy- Gut wall Deck (57)
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1
Q

How are the abdominal and pelvic cavities separated?

A

They are continous except for the presence of the pelvic brim/inlet

2
Q

List the 9 regions of the abdomen, from superior to inferior

A
  • Right hypochondrium
  • Epigastric
  • Left hypochondrium
  • Right lumbar(/flank)
  • Umbilical
  • Left lumbar(/flank)
  • Right iliac(/groin)
  • Hypogastric(/suprapubic)
  • Left iliac(/groin)
3
Q

How can the abdomen be divided?

A
  • 9 regions

- 4 quadrants

4
Q

Describe the contents of the abdominal wall from superficial to deep

A
  • Skin
  • Subcutaneous fat
  • Campers fascia
  • Scarpas fascia
  • External oblique
  • Internal oblique
  • Transversys abdominis
  • Extraperitoneal fat
  • Endoabdominal fat
  • Parietal peritoneum
5
Q

Describe how the campers fascia and scarpas fascia differ in structure

A
  • Campers fascia is fatty layer of subcutaneous tissue

- Scarpas fascia is deep, membranous layer of subcutaneous tissue

6
Q

List the muscles in the anterior wall of the abdomen

A

Paired rectus abdominis muscles within the rectus sheath

7
Q

List the muscles in the lateral wall of the abdomen

A
  • External oblique
  • Internal oblique
  • Transversus abdominis
8
Q

List the muscles in the posterior wall of the abdomen

A
  • Post vertebral muscles (erector spinae)

- Psoas, quadratus lumborum and iliacus muscles

9
Q

What is another name for the muscles making up the lateral wall of the abdomen?

A

Flank sheet muscles

10
Q

List the function of the flank sheet muscles

A
  • Compress the abdomen, increasing the intra-abdominal pressure to aid expiration, evacuation of urine, faeces, partuition, heavy lifting
  • Supports viscera (mainly intestines)
  • Flex and rotate the trunk
11
Q

List the attachments of the external oblique

A
  • External surface of lower 8 ribs
  • Free posterior border
  • Fans out to attach to the xiphoid process, linea alba, pubic creast & tubercle, anterior half of the iliac crest
12
Q

Describe the direction of the muscle fibres in the external oblique

A

Downward and outward

13
Q

Describe where the aponeurosis of the external oblique attaches to, and the structure it forms

A
  • Fuses medially with the rectus sheath

- Lower edge rolls inwards to form the inguinal ligament

14
Q

List the lateral attachments of the internal oblique

A
  • Thoracolumbar fascia
  • Iliac crest (anterior 2/3rd)
  • Inguinal ligament (lateral half)
15
Q

List the medial attachments of the internal oblique

A
  • Lower 3 ribs and costal cartilages
  • xiphoid process
  • Rectus sheath
  • Conjoint tendon
16
Q

Describe the direction of the internal oblique

A

Downward and backward

17
Q

List the lateral attachments of the transversus abdominis

A
  • Lower 6 costal cartilages
  • Thoracolumbar fascia
  • Iliac crest (anterior 2/3rd)
  • Inguinal ligament (lateral 2/3rd)
18
Q

List the medial attachments of the transversus abdominis

A
  • xiphoid process
  • Linea alba
  • Symphysis pubis
  • Conjoint tendon
  • Neurovascular plane lies between the internal oblique and transversus absominis
19
Q

Describe the direction of muscle fibres in the transversus abdominis

A

Horizontally

20
Q

List the attachments of the rectus abdominis

A
  • Lateral attachment to the linea semilunaris
  • Superior attachment to 5-7 costal cartilages and xiphoid process
  • Inferior attachment to the symphysis pubis and pubic crest
  • Meets at the linea alba (midline)
21
Q

What is the rectus sheath, and how does its structure change?

A
  • The rectus sheath is formed by the aponeuroses of 3 muscles
  • Above the umbilicus, the internal oblique aponeurosis splits to enclose the rectus abdominis, while the external oblique is infront and the transversus behind the rectus muscle
  • Below the umbilicus all 3 aponeurotic layers are anterior to the rectus muscle
22
Q

What is the function and attachment of the psosis major?

A
  • Attachment to bodies and discs of all 5 lumar vertebrae and the lesser trochanter of femur
  • Acts as the flexor of the hip and trunk
23
Q

What is the function and attachment of the quadratus lumborum?

A
  • Attachment to the lower border of 12th rib and transverse process of 5th lumbar vertebra and adjacent iliac crest
  • Stabilises the 12th rib and acts as a lateral flexor of the trunk
24
Q

Describe the blood supply of the rectus muscle

A
  • Superior epigastric artery (terminal branch of internal thoracic)
  • Inferior epigastric artery (branch of external iliac)
  • Enter the rectus sheath and anastomose to form a bypass to the abdominal aorta
25
Q

Describe the blood supply of the flank muscles

A
  • Segmentally supplied
  • Intercostal arteries 7-11
  • Subcostal artery
  • Lumbar arteries
  • Deep circumflex iliac arteries
26
Q

What is the neurovascular plane of the abdominal wall?

A

Between the internal oblique and transversus abdominis muscle

27
Q

List the motor nerves supplying the abdominal wall

A
  • Segmentally supplied by T7-T12 and L1
  • External oblique is supplied by T7-T11
  • Internal oblique and transversus by T7-T12&L1
  • Rectus by T7-T12
28
Q

What are the dermatomes in the abdomen?

A

T7 - epigastrum
T10 - umbilicus
L1 - inguinal ligament

29
Q

Compare the innervation of the parietal and visceral peritoneum.

A
  • Parietal supplied by the same nerves as the part of the body wall it is covering
  • Visceral has no somatic sensory innervation
30
Q

Describe the nerves supplying the antero-lateral abdominal wall

A
  • Subcostal nerve (T12)
  • Iliohypogastric (L1)
  • Iliolingual (L1)
31
Q

Describe the motor supply to the posterior abdominal wall

A
  • Quadratus lumorum T12 & L1-4
  • Psoas major L2-4
  • Iliacus (femoral nerve) L2-4
32
Q

Describe the significance of the lumbar plexus (L1-4) in the abdomen

A
  • Mainly for the lower limb

- Sensory branches to the parietal peritoneum of the posterior abdominal wall

33
Q

Describe the lymohatic drainage on the abdominal wall

A

No drainage

34
Q

Describe the lymphatic drainage of the superficial tissues

A
  • Superficial lymphatics accompany veins
  • Drainage occurs in quadrants
  • Above the transumbilical plane, there is drainage to axillary nodes
  • Below the transumbilical plane there is drainage to the superficial inguinal nodes
35
Q

Describe the lymphatic drainage of deeper tissues

A
  • Deep lymphatics accompany deep veins in the extraperitoneal tissues
  • Above the transumbilical plane there is drainage to mediastinal nodes
  • Below the transumbilical plane there is drainage to external iliac and para-aortic nodes
36
Q

What is the inguinal region?

A
  • The junction between the anterior abdominal wall and the thigh
  • Between the anterio-superior illiac spine and the pubic tubercle
37
Q

Why is the inguinal region important?

A
  • Clinically important as it is weak so a potential site for hernias
  • Anatomically important because structures enter and exit the abdominal cavity
38
Q

Describe the anatomy of the inguinal canal

A
    • ASIS to pubic tubercle
  • Deep inguinal ring is superior
  • Superficial inguinal ring is inferior.
  • Formed due to the descent of the testes and spermatic cord in males, and the uterine round ligament in females
  • Bigger in males
39
Q

Describe the structure of the femoral canal

A
  • Only has lymphatics running through it
  • Lateral to the inguinal canal
  • The accompanying artery and vein are inside of the femoral sheath, with the nerves outside of the sheath
40
Q

Define hernia

A

A condition in which part or whole of an organ or tissue abnormally protrude through the wall of the structure containing the organ or tissue.

41
Q

Describe the basic structure of a hernia

A
  • Intestinal loop in the hernial sac

- Weakness in the wall

42
Q

List the clinical signs and symptoms of a hernia

A
  • A lump or protrusion in the groin
  • Appears intermittently or present all the time
  • Painless/painful and uncomfortable
  • Hernia may be reducible or irreducible
  • May be strangulated with tissue death- and associated with vomiting, constipation, intestinal obstruction – this is an emergency situation
43
Q

List and describe the types of inguinal hernia

A
  • Indirect (congenital) inguinal hernia pass through the deep and superficial ring of the iliac canal, going through the hesselbach’s triangle (medial to internal epigastric vessels)
  • Direct (acquired) inguinal hernias pass through only the superficial ring, lateral to the inferior epigastric vessels
44
Q

Describe the location of the inguinal canal

A
  • 4cm long
  • Lies above the medial half of the inguinal ligament
  • Deep inguinal ring (hole in the transversalis facia) to superficial (hole in external oblique aponeurosis
  • Deep ring 1.5cm above midpoint of inguinal ligament
  • Superficial ring immediately above and medial to the pubic tubercle
45
Q

List the contents of the inguinal canal

A
  • Illiolingual nerve and genital branch of genito-femoral nerve (in males and females)
  • In males spermatic cord
  • In females round ligament
46
Q

What is the anterior wall of the inguinal canal?

A
  • External oblique aponeurosis (whole length)

- Internal oblique muscle reinforces the lateral 3rd of the canal

47
Q

What is the floor of the inguinal canal?

A

Inguinal ligament (stretches between ASIS and pubic tubercle)

48
Q

What is the roof of the inguinal canal?

A
  • Arching fibres of the internal oblique muscle and transverse abdominis muscle (whole length)
  • Medially conjoint tendon, formed of the internal oblique and transversus abdominis aponeurosis joining
49
Q

What is the posterior wall of the inguinal canal?

A
  • Transversalis fascia

- Medially conjoint tendon

50
Q

List the causes of a direct inguinal hernia

A
  • Older age group
  • Caused by straining/weak musculature
  • An acquired defect in the posterior wall of the inguinal canal
51
Q

List the borders of Hasselbach’s triangle

A
  • Rectus abdominis
  • Inguinal ligament
  • Inferior epigastric vessels
52
Q

List the causes of indirect inguinal hernia

A
  • Most common type
  • Tend to be in younger adults and children
  • The defect is a dilated deep ring
  • The hernia enters the deep ring then passes through the inguinal canal, external inguinal ring and into the scrotum
53
Q

List the characteristics of femoral hernias

A
  • Hernia through the femoral canal
  • Not as common as inguinal hernias
  • Commoner in elderly and females
  • Have a high incidence of obstruction and strangulation
  • Irreducible
  • Below and lateral to the pubic tubercle
54
Q

List the borders of the femoral canal

A

Superior – Inguinal ligament
Inferior – Pectineus fascia
Medial – Lacunar ligament
Lateral – Femoral vein

55
Q

Describe the location of inguinal hernias

A

Above and medial to the pubic tubercle

56
Q

How can the borders of the inguinal canal be remembered?

A

M - Muscle (transversalis abdominis and internal oblique) ROOF
A - External oblique aponeurosis ANTERIOR
L - Inguinal ligament and lacunar ligament FLOOR
T - Transversalis fascia and conjoint tendon POSTERIOR

57
Q

Compare the pathway of the inguinal ligament to the pathway of the inguinal canal

A
  • Inguinal ligament passes from the ASIS to the pubic tubercle
  • Inguinal canal passes from the ASIS to the pubic symphysis