Anatomy of the Intestines Flashcards Preview

ESA 3 - GI Anatomy > Anatomy of the Intestines > Flashcards

Flashcards in Anatomy of the Intestines Deck (219)
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1
Q

Is the duodenum mobile?

A

No

2
Q

Where is the duodenum, in relation to the peritoneum?

A
  • The proximal first segment is intraperitoneal
  • The rest is secondarily retroperitoneal
3
Q

Are the jejenum and ileum mobile?

A

Yes

4
Q

Are the ascending and descending colon mobile?

A

No

5
Q

Where are the ascending and descending colon, in relation to the peritoneum?

A

Secondarily retroperitoneal

6
Q

Does the caecum have a mesentery?

A

No

7
Q

What is the caecum commonly bound to?

A

The lateral abdominal wall

8
Q

What is the caecum commonly bound to the lateral abdominal wall by?

A

A fold of peritoneum

9
Q

What is the transverse colons mesentery called?

A

The transverse mesocolon

10
Q

What is the transverse mesocolon adhered to?

A

The posterior wall of the omental bursa

11
Q

How does the lumen diameter of the small intestine differ from the large intestine?

A

It is smaller

12
Q

Describe the longitudinal muscle in the small intestine

A

Continuous layer

13
Q

Describe the longitudinal muscle in the large intestine

A

Reduced to three bands- teniae coli

14
Q

Does the small intestine have fatty tags?

A

No

15
Q

Does the large intestine have fatty tags?

A

Yes, attached to its wall

16
Q

What are the fatty tags of the large intestine called?

A

Appendices epiploicae

17
Q

How does the wall of the small and large intestine differ?

A
  • Small is smooth
  • Large is sacculated
18
Q

What does the saculated wall of the large intestine form?

A

Haustra

19
Q

Describe the mucous membrane of the small intestine

A

Permanent folds

20
Q

What are the mucous membrane folds of the small intestine called?

A

Plicae circulares

21
Q

Describe the mucous membrane of the large intestine

A

Incomplete folds may be present

22
Q

Describe the lymphoid tissue in the small intestine

A

Peyer’s patches

23
Q

Describe the lymphoid tissue in the large intestine

A

None

24
Q

How does the duodenum compare to the other sections of the small intestine?

A
  • Shortest
  • Widest
  • Most fixed
25
Q

How long is the duodenum?

A

25cm

26
Q

What course does the duodenum persue?

A

A C-shaped course around the head of the pancreas

27
Q

Where does the duodenum begin?

A

At the pylorus, on the right side

28
Q

Where does the duodenum end?

A

At the duodenojejenal flexure (junction), on the left side

29
Q

Where does the duodenojejunal junction occur?

A

At approximately the level of the L2 vertebrae, 2-3cm left of the midline

30
Q

What does the duodenojejunal junction usually take the form of?

A

An acute angle

31
Q

What is most of the duodenum fixed to?

A

The structures on the posterior abdominal wall

32
Q

What fixes most of the duodenum to the posterior abdominal wall?

A

Peritoneum

33
Q

What is the duodenum considered to be, with regards to the peritoneum?

A

Partly retroperitoneal

34
Q

Label this diagram

A
  • A - Liver
  • B - Gallbladder
  • C - Pylorus
  • D - Duodenum
  • E - Right colic flexure
  • F - Duodenojejunal junction
  • G - Ascending colon
  • H - Stomach
  • I - Pancreas
  • J - Left colic flexure
  • K - Transverse colon
  • L - Jejenum
35
Q

What parts is the duodenum considered to be divisible into?

A
  1. Superior part
  2. Descending part
  3. Inferior part
  4. Ascending part
36
Q

How long is the superior part of the duodenum?

A

5cm

37
Q

Where does the superior part of the duodenum lie?

A

Anterolateral to the body of the L1 vertebra

38
Q

How long is the descending part of the duodenum?

A

7-10cm

39
Q

Where does the descending part of the duodenum run?

A

Along the rght sides of L1-L3 vertebrae

40
Q

How long is the inferior part of the duodenum?

A

6-8cm

41
Q

Where does the inferior part of the duodenum cross?

A

The L3 vertebrae

42
Q

How long is the ascending part of duodenum?

A

5cm

43
Q

Where does the ascending part of the duodenum begin?

A

At the level of the L3 vertebra

44
Q

What course does the ascending part of the duodenum take?

A

Rises superiorly as far as the superior border of the L2 vertebra

45
Q

Label this diagram

A
  • A - Hepatic portal vein
  • B - Hepatic artery
  • C - Bile duct
  • D - Ampulla (duodenal cap)
  • E - Supraduodenal artery
  • F - Pylorus of stomach
  • G - Gastroduodenal artery
  • H - Anterior superior pancreaticduodenal artery
  • I - Right gastro-epiploic artery
  • J - Superior mesenteric vein and artery
  • K - Anterior inferior pancreatico-duodenal artery
  • L - Right colic artery and vein
  • M - Ileocolic vein and artery
  • N - Mesentery (cut edge)
  • O - Middle colic artery
  • P - Duodenojejunal junction
  • Q - Pancreas
  • R - Spleen
  • S - Splenic vessels
  • T - Oesophageal branches
  • U - Left gastric artery and veins
  • V - Lymph nodes
46
Q

What is the duodenal cap/ampulla?

A

The first 2cm of the superior part of the duodenum

47
Q

Where is the ampulla found?

A

Immediately distal to the pylorus

48
Q

Does the ampulla have a mesentery?

A

Yes

49
Q

Is the ampulla mobile?

A

Yes

50
Q

Is the ampulla retroperitoneal?

A

No

51
Q

What is the ampulla a common site of?

A

Ulceration

52
Q

Why is the ampulla a common site of ulceration?

A

Because it is immediately distal to the pylorus

53
Q

What can be a complication of an ampulla ulcer?

A

If the ulcer erodes backwards through the gastroduodenal artery, blood loss can be severe

54
Q

What does the superior part of duodenum ascend from?

A

The pylorus

55
Q

What is the superior part of the duodenum overlapped by?

A

The liver and gallbladder

56
Q

Describe the relationship between the superior part of the duodenum and peritoneum?

A
  • Peritoneum covers its anterior aspects
  • It is bare of peritoneum posteriorly (exept for duodenal cap)
57
Q

What does the the proximal part of the superior part of the duodenum have attached superiorly?

A

The hepatoduodenal ligament

58
Q

What is the hepatoduodenal ligament part of?

A

The lesser omentum

59
Q

What does the proximal part of the superior part of the duodenum have attached inferiorly?

A

The greater omentum

60
Q

Where does the descending part of the duodenum run?

A

Inferiorly, curving around the head of the pancreas

61
Q

What enters the descending part of the duodenum?

A

The bile and main pancreatic ducts

62
Q

How do the bile and main pancreatic ducts enter the descending part of the duodenum?

A

Via the Ampulla of Vater

63
Q

Where does the Ampulla of Vater enter the descending part of the duodenum?

A

Its posteromedial wall

64
Q

Describe the relationship between the descending part of the duodenum and the peritoneum?

A
  • It is entirely retroperitoneal
  • The anterior surface of its proximal and distal thirds is covered with peritoneum
  • The peritoneum reflects in its middle third
65
Q

What is formed when the peritoneum reflects in the middle third of the descending part of the duodenum?

A

The double-layered mesentery of the transverse colon, the transverse mesocolon

66
Q

How does the inferior part of the duodenum run?

A

Transversely right to left

67
Q

What does the inferior part of the duodenum pass over?

A

The IVC, aorta, and L3 vertebra

68
Q

What crosses the inferior part of the duodenum?

A
  • The superior mesenteric artery and vein
  • The root of the mesentery of the jejenum and ileum
69
Q

Describe the relationship between the inferior part of the duodenum and the peritoneum

A

Is is completely covered in peritoneum apart from where structures cross it

70
Q

What is the inferior part of the duodenum seperated from the vertebral column by?

A
  • Right psoas major
  • IVC
  • Aorta
  • Right testicular/ovarian vessels
71
Q

Where does the ascending part of the duodenum run?

A

Superiorly, and along the left side of the aorta to reach the inferior border of the body of the pancreas

72
Q

What happens to the ascending part of the duodenum when it reaches the inferior border of the body of the pancreas?

A

It curves anteriorly to join the jejenum at the duodenojejunal flexure

73
Q

What is the ascending part of the duodenum spported by at the duodenojejunal flexure?

A

The attachment of a suspensory muscle of the duodenum (Ligament of Treitz)

74
Q

What is the result of the contraction of the suspensory muscle of the duodenum?

A

It widens the flexure, facilitating movement

75
Q

Where does the jejunum begin?

A

At the duodenojejenal flexure

76
Q

What happens at the duodenojejunal flexure?

A

The digestive tract resumes an intraperitoneal course

77
Q

Where does the ileum end?

A

The ileocaecal junction

78
Q

How long are the jejunum and ileum together?

A

6-7m

79
Q

What proportion of the intraperitoneal section of the small intestine is jejenum?

A

~2/5

80
Q

What proportion of the intraperitoneal section of the small intestine is ileum?

A

3/5

81
Q

Where does most of the jejeum lie?

A

In the left upper quadrant (LUQ) of the infracolic compartment

82
Q

Where does most of the ileum lie?

A

In the right lower quadrant (RLQ)

83
Q

Where does the terminal ileum usually lie?

A

In the pelvis

84
Q

What happens to the terminal ileum in the pelvis?

A

It ascends, ending in the medial aspect of the cecum

85
Q

What is the mesentery?

A

A fan-shaped fold of peritoneum

86
Q

What does the mesentery do?

A

Attaches the jejenum and ileum to the posterior abdominal wall

87
Q

What is found between the two layers of the mesentery?

A
  • The superior mesenteric vessels
  • Lymph nodes
  • Variable amount of fat
  • Autonomic nerves
88
Q

What does the root of the mesentery cross?

A
  • Ascending and inferior parts of duodenum
  • Abdominal aorta
  • IVC
  • Right ureter
  • Right psoas major
  • Right testicular/ovarian vessels
89
Q

Label this diagram

A
  • A - Duodenum
  • B - Duodenojejunal junction
  • C - Ileocecal junction
  • D - Cecum
  • E - Appendix
90
Q

What colour is the jejenum?

A

Deeper red

91
Q

What colour is the ileum?

A

Paler pink

92
Q

What is the diameter of the jejunum?

A

2-4cm

93
Q

What is the diameter of the ileum?

A

2-3cm

94
Q

How does the wall of the jejenum and ileum differ?

A
  • Jejenum wall is thick and heavy
  • Ileum wall is thin and light
95
Q

Does the jejenum or ileum have greater vascularity?

A

Jejenum

96
Q

How do the vasa recta in the jejenum and ileum differ?

A
  • Long in jejenum
  • Short in ileum
97
Q

Describe the arcades of the jejunum

A

A few large loops

98
Q

Describe the arcades in the ileum

A

Many short loops

99
Q

Does the jejunum or ileum have more fat in the mesentery?

A

Ileum

100
Q

Describe the circulae folds in the jejunum?

A
  • Large
  • Tall
  • Closely packed
101
Q

Describe the circulae folds in the ileum

A
  • Low
  • Sparse
  • Absent in distal part
102
Q

How many Peyer’s patches are in the jejenum?

A

Few

103
Q

How many Peyers patches are in the ileum?

A

Many

104
Q

What is the intestinal adult derivative of the foregut?

A

Duodenum (proximal to bile duct)

105
Q

What is the intestinal adult derivative of the midgut?

A
  • Duodenum (distal to bile duct)
  • Jejunum/ileum
  • Cecum/ascending colon
  • Proximal 2/3 transverse colon
106
Q

What is the intestinal adult derivative of the hindgut?

A
  • Distal 1/3 transverse colon
  • Descending/sigmoid colon
  • Rectum/upper anal canal
107
Q

What is the blood supply to the intestinal adult derivates of the foregut?

A

Celiac trunk

108
Q

What is the blood supply to the intestinal adult derivates of the midgut?

A

Superior mesenteric artery and vein

109
Q

What is the blood supply to the intestinal adult derivates of the hindgut?

A

Inferior mesenteric artery and vein

110
Q

What is the duodenum dervied from?

A

Both midgut and foregut

  • Proximal to bile duct, duodenum derived from foregut
  • Distal to bile duct, derived from midgut
111
Q

What is the blood supply to the duodenum proximal to the bile duct?

A

From the coeliac trunk, via the gastroduodenal artery and its branch the superior pancreaticoduodenal artery

Coeliac trunk -> Gastroduodenal -> Superior pancreaticoduodenal

112
Q

What is the duodenum distal to the bile duct derived from?

A

The midgut

113
Q

What is the blood supply of the duodenum distal to the bile duct?

A

From the superior mesenteric artery, through its branch the inferior pancreaticoduodenal artery

Abdominal aorta -> SMA -> Inferior Pancreaticoduodenal

114
Q

Where do the pancreaticoduodenal arteries lie?

A

In a curve between the duodenum and the head of the pancreas

115
Q

What do the veins of the duodenum follow?

A

The arteries

116
Q

What do the veins of duodenum drain into?

A

The hepatic portal vein

  • Some directly
  • Some through the superior mesenteric and splenic veins
117
Q

Label this diagram

A
  • A - Right gastric artery
  • B - Common hepatic artery
  • C - Right gastro-omental artery
  • D - Gastroduodenal artery
  • E - Superior pancreaticoduodenal artery
  • F - Posterior superior pancreaticoduodenal artery
  • G - Anterior superior pancreaticoduodenal artery
  • H - Duodenum
  • I - Posterior inferior pancreaticoduodenal artery
  • J - Anterior inferior pancreaticoduodenal artery
  • K - Superior mesenteric artery
  • L - Inferior pancreaticoduodenal artery
  • M - Pancreas
  • N - Splenic artery
  • O - Left gastro-omental artery
  • P - Spleen
  • Q - Short gastric artery
  • R - Left gastric artery
  • S - Celiac trunk
118
Q

What are the jejunum and ileum derived from embryological?

A

Midgut

119
Q

What is the result of the jejunum and ileum both being derived from the midgut?

With regard to the arteries

A

Their blood supply is derived from the superior mesenteric artery, via the jejunal and ileal arteries

120
Q

What does the jejunal artery arise from?

A

Abdominal aorta -> SMA

121
Q

What does the ileal artery arise from?

A

Abdominal aorta -> SMA

122
Q

Where does the SMA usually arise from the abdominal aorta?

A

At the level of the L1 vertebra, approx. 1cm inferior to the celiac trunk

123
Q

Where does the superior mesenteric artery run?

A

Between the layers of the mesentery

124
Q

How many branches does the superior mesenteric artery send to the jejunum and ileum?

A

15-18

125
Q

What happens to the branches of the SMA sent to the jejunum and ileum?

A

These arteries unite to form loops or arches called arterial arcades

126
Q

What do the arterial arcades give rise to?

A

Straight arteries called vasa recta

127
Q

Label this diagram

A
  • A - Hepatic portal vein
  • B - Common hepatic artery
  • C - Gastroduodenal artery
  • D - Right gastro-omental artery
  • E - Duodenum
    F - Ileocolic artery
  • G - Ileal branch
  • H - Cecum
  • I - Appendix
  • J - Celiac trunk
  • K - Pancreas
  • L - Superior mesenteric artery (SMA)
    M - Superior mesenteric vein
  • N - Jejunum
  • O - Jejunal arteries
  • P - Arterial arcades
  • Q - Ileal arteries
  • R - Vasa recta (straight arteries)
  • S - Ileum
128
Q

Label this diagram

A
  • A - Jejunum
  • B - Windows
  • C - Vasa recta
  • D - Arterial arcades
129
Q

Label this diagram

A
  • A - Ileum
  • B - Enroaching fat
  • C - Vasa recta
  • D - Arterial arcades
130
Q

What does the large intestine consist of?

A
  • Caecum
  • Appendix
  • Ascending colon
  • Transverse colon
  • Descending colon
  • Sigmoid colon
  • Rectum
  • Anal canal
131
Q

How can the large intestine be distinguished from the small intestine?

A
  • Omental appendices
  • Teniae coli
  • Haustra
  • Diameter
132
Q

What are omental appendices?

A

Small, fatty, omentum like projections

133
Q

What are teniae coli?

A

Three distinct longitudinal bands of muscle

134
Q

Where do teniae coli begin?

A

At the appendix

135
Q

How does the teniae coli begin at the appendix?

A

The appendixes longitudinal muscle splits into 3 bands

136
Q

Where do teniae coli run?

A

The length of the large intestine

137
Q

What happens to the teniae coli to terminate them?

A

Merge together again at the rectosigmoid junction into a continuous layer around the rectum

138
Q

What are haustra?

A

Sacculations of the wall of the colon between teniae

139
Q

How does the diameter of the large intestine differ to that of the small?

A

It is much larger

140
Q

Label this diagram

A
  • A - Right colic flexure
  • B - Omental appendices
  • C - Ascending colon
  • D - Mesocolic tenia coli
  • E - Ascending branch of ileocolic artery
  • F - Anterior and posterior cecal branches of ileocolic artery
  • G - Cecum
  • H - Mesoappendix
  • I - Appendicular artery
  • J - Appendix
  • K - Ileocolic artery
  • L - Ileal branch of ileocolic artery
  • M - Ileocecal recess and fold
    • mi - Superior
    • mii - inferior
  • N - Transverse colon
  • O - Omental tenia coli
  • P - Semilunar folds
  • Q - Haustra
  • R - Left colic flexure
  • S - Descending colon
  • T - Free tenia coli
  • U - Sigmoid colon
  • V - Long omental appendices
  • W - Rectum
  • X - Anal canal
141
Q

What is the caecum?

A

The first part of the large intestine

142
Q

What is the caecum continuous with?

A

The ascending colon

143
Q

What is the caecum continuous with?

A

The ascending colon

144
Q

How could the caecum be described?

A

As a blind intestinal pouch

145
Q

How big is the caecum?

A

Approx. 7.5cm in both length and breadth

146
Q

Where does the caecum lie?

A

In the iliac fossa of the right lower quadrant of the abdomen, inferior to the junction of the terminal ileum and caecum (ileocaecal junction)

147
Q

Is the caecum palpable through the anterolateral abdominal wall?

A

Under some circumstances

148
Q

Under what circumstances is the caecum palpable through the anterolateral abdominal wall?

A

If distended with faeces or gas

149
Q

How close is the caecum to the inguinal ligament?

A

Usually lies within 2.5cm of it

150
Q

What is the relationship between the caecum and the peritoneum?

A

It is almost entirely enveloped by peritoneum

151
Q

Is the caecum mobile?

A

Yes

152
Q

Does the caecum have mesentery?

A

No

153
Q

What is the result of the relative freedom of the caecum?

A

It can be displaced from the iliac fossa

154
Q

What is the caecum commonly bound to?

A

The lateral abdominal wall

155
Q

What is the caecum commonly bound to the lateral abdominal wall by?

A

One or more cecal folds of peritoneum

156
Q

Label this diagram

A
  • A - Cecal folds
  • B - Ileal papilla
  • C - Ileal orifice
  • D - Ileum
  • E - Opening of appendix
  • F - Cecum
157
Q

What is the appendix?

A

A blind intestinal diverticulum

158
Q

How big is the appendix?

A

6-10cm

159
Q

What does the appendix contain?

A

Masses of lymphoid tissue

160
Q

What does the appendix arise from?

A

The posteromedial aspect of the caecum inferior to the ileocecal junction

161
Q

Where does the appendix sit in relation to the caecum?

A

Usually retrocaecal, but its position is variable

162
Q

Does the appendix have a mesentery?

A

Yes, the mesoappendix

163
Q

Describe the mesoappendix

A

A short, triangular mesentery

164
Q

What is the mesoappendix derived from?

A

The posterior side of the mesentery of the terminal ileum

165
Q

What does the mesoappendix attached to?

A

The caecum and proximal part of the appendix

166
Q

What is the caecum derived from embryologically?

A

Midgut

167
Q

What is the result of the caecum being midgut derived?

With regards to its arterial supply

A

It receives its blood supply from the SMA, by way of the ileocolic artery

168
Q

What is the ileocolic artery?

A

SMA terminal branch

169
Q

What is the appendix derived from embryologically?

A

Midgut

170
Q

What is the result of the appendix being midgut derived?

With respect to the arterial supply

A

It receives its blood supply from the SMA, by way of the appendicular artery

171
Q

What is the venous drainage from the caecum and appendix?

A

Flows through a through a tributary of the SMV, the ileocolic vein

172
Q

Label this diagram

A
  • A - Superior mesenteric artery
  • B - Middle colic artery
  • C - Right colic artery
  • D - Ileocolic artery
  • E - Cecum
  • F - Appendicular artery
  • G - Appendix
  • H - Superior rectal artery
173
Q

Label this diagram

A
  • A - Ileocolic vein
  • B - Right colic vein
  • C - Middle colic vein
  • D - Superior mesenteric vein
  • E - Hepatic portal vein
  • F - Inferior mesenteric vein
  • G - Left colic vein
  • H - Sigmoid and recto-sigmoid veins
174
Q

What are the parts of the colon?

A
  • Ascending
  • Transverse
  • Descending
  • Sigmoid
175
Q

Where does the ascending colon pass?

A

Superiorly on the right side of the abdominal cavity, from the caecum to the right lobe of the liver

176
Q

What happens to the ascending colon at the right lobe of the liver?

A

It turns to the left at the right colic flexure (hepatic flexure)

177
Q

Where does the right colic flexure lie?

A

Deep to the 9th and 10th ribs

178
Q

What is the right colic flexure overlapped by?

A

The inferior part of the liver

179
Q

Is the caecum or the ascending colon narrower?

A

The ascending colon

180
Q

What is the relationship between the ascending colon and the peritoneum?

A
  • It is secondarily retroperitoneal along the right side of the posterior abdominal wall
  • Covered by peritoneum anteriorly and on its sides
181
Q

How is the ascending colon seperated from the anterolateral abdominal wall?

A

By the greater omentum

182
Q

What % of people have a short mesentery of the ascending colon?

A

25%

183
Q

What is the right paracolic gutter?

A

A deep vertical groove lined with parietal peritoneum in the ascending colon

184
Q

Where does the right paracolic gutter lie?

A

Between the lateral aspect of the ascending colon and the adjacent abdominal wall

185
Q

How does the transverse colon differ from the other parts of the colon?

A
  • Longest
  • Most mobile
186
Q

How does the transverse colon cross the abdomen?

A

From the right to left colic flexures (splenic flexure)

187
Q

What happens to the transverse colon at the left colic flexure?

A

It turns inferior before becoming the descending colon

188
Q

How does the left colic flexure differ from the right colic flexure?

A
  • More superior
  • More acute
  • Less mobile
189
Q

Where does the left colic flexure lie?

A

Anterior to inferior part of the left kidney

190
Q

What is the left colic flexure attached to?

A

The diaphragm

191
Q

How is the left colic flexure attached to the diaphragm?

A

Through the phrenocolic ligament

192
Q

Does the transverse colon have a mesentery?

A

Yes, the transverse mesocolon

193
Q

What course does the transverse colon and its mesentery take?

A

Loops down, often inferior to the level of the iliac crests

194
Q

What is the mesentery adherent to or fused with?

A

The posterior wall of the omental bursa

195
Q

Where does the root of the transverse mesocolon lie?

A

Along the inferior border of the pancreas

196
Q

What is the transverse mesocolon continuous with?

A

The parietal peritoneum posteriorly

197
Q

Is the transverse colon freely moveable?

A

Yes

198
Q

What is the result of the transverse colon being freely movable?

A

The transverse colon is variable in position

199
Q

What position does the transverse colon usually take?

A

Hangs down to the level of the umbilicus (L3), but in tall, thin people, it may extend down into the pelvis

200
Q

What is the relationship between the descending colon and the mesentery?

A
  • It is secondarily retroperitoneal
  • Covered by peritoneum anteriorly and laterally
201
Q

What is the result of the peritoneal covering of the posterior descending colon?

A

Binds it to the posterior abdominal wall

202
Q

Where is the descending colon found?

A

Between the left colic flexure and the left iliac fossa

203
Q

What happens to the descending colon at the left iliac fossa?

A

It is continuous with the sigmoid colon

204
Q

Where does the descending colon pass as it descends?

A

Anterior to the lateral border of the left kidney

205
Q

What % of people have a short mesentery of the descending colon?

A

33%

206
Q

What is the left paracolic gutter?

A

A deep vertical groove lined with parietal peritoneum in the descending colon

207
Q

Where does the left paracolic gutter lie?

A

Between the lateral aspect of the ascending colon and the adjacent abdominal wall

208
Q

What is the sigmoid colon characterised by?

A

Its S-shaped loop of variable length

209
Q

What does the sigmoid colon link?

A

The descending colon and the rectum

210
Q

Where does the sigmoid colon run?

A

From the iliac fossa to the S3 vertebrae

211
Q

What indicates the rectosigmoid junction?

A

The terminatiation of the teniae coli

212
Q

Where do the teniae coli terminate?

A

Approx. 15cm from the anus

213
Q

Does the sigmoid colon have a mesentery?

A

Yes, usually long

214
Q

What is the result of the sigmoid colons long mesentery?

A

It has considerable mobility, especially its middle part

215
Q

What can the mobility of the sigmoid colon lead to?

A

Volvulus of the sigmoid colon

216
Q

What does the root of the sigmoid mesocolon have?

A

An inverted V-shaped attachment

217
Q

Where does the attachment of the sigmoid mesocolon extend?

A

Medially and superiorly along the external iliac vessels to the anterior aspect of the sacrum

218
Q

What is found posterior to the apex of the root of the sigmoid mesocolon?

A

The left ureter and division of the left common iliac artery

219
Q

What is the relationship between the left ureter and the divison of the left common iliac artery that lies posterior to the apex of the root of the sigmoid mesocolon?

A

Lie retroperitoneally