Abdominal wall Flashcards
1
Q
What are the divisions of the abdominal wall
A
Anterolateral
Posterior
2
Q
What is the superior border of the anterolateral abdominal wall
A
Cartilages of ribs 7-10
Xiphoid process
3
Q
What is the inferior border of the anterolateral abdominal wall
A
Inguinal ligament
Superior margins of anterolateral aspects of the pelvic girdle
4
Q
What does the anterolateral abdominal wall consist of from superficial to deep
A
Skin
Superficial fatty subcutaneous tissue (camper fascia)
Scarpa fascia
External oblique, internal oblique and transversus abdominis separated by deep fascia (superficial, intermediate and deep)
Endoabdominal fascia
Extra peritoneal fat
Parietal peritoneum
5
Q
What spinal level is the umbilicus at
A
L3
6
Q
What is the epigastric fossa
A
Depression in the epigastric region just inferior to the xiphoid process
7
Q
What is the linea alba
A
Aponeuroses of abdominal muscles that separates the left and right rectus abdominis
8
Q
What is divarication of recti and what increases its likelihood
A
When the rectus abdominis contract the muscles spread apart if the linea alba is lax
More likely in elderly and in women who have had lots of children (pregnancy stretches Linea Alba)
9
Q
What is the inguinal groove
A
Skin crease parallel and inferior to the inguinal ligament that separates the thigh and abdominal wall
10
Q
What are the semilunar lines
A
Curved tendinous lines either side of the rectus abdominis
11
Q
Where is the arcuate line (Douglas’ line)
A
Inferior limit of the posterior layer of the rectus sheath
1/3 way from umbilicus to the pubic crest
12
Q
What are the flat muscles in the anterolateral abdominal wall
A
External oblique
Internal oblique
Transversus abdominis
13
Q
What are the vertical muscles of the anterolateral abdominal wall
A
Rectus abdominis
Pyramidalis
14
Q
What are the orientations of the anterolateral abdominal wall muscle fibres
A
External oblique - inferomedial
Internal oblique - superomedial
(Perpendicular)
Transversus abdominis - medial
15
Q
Origin of external oblique muscle
A
Ribs 5-12 (external)
16
Q
Insertion of external oblique muscle
A
Linea alba
Pubic tubercle
Anterior half of iliac crest
17
Q
Origin of internal oblique muscle
A
Thoracolumbar fascia
Anterior 2/3 of iliac crest
CT deep to lateral 1/3 of inguinal ligament
18
Q
Insertion of internal oblique muscle
A
Inferior borders of ribs 10-12
Linea alba
Pectin pubis via the conjoint tendon
19
Q
Origin of transversus abdominis muscle
A
Costal cartilage of ribs 7-12 (internal)
Thoracolumbar fascia
Iliac crest
CT deep to lateral 1/3 of inguinal ligament
20
Q
Insertion of transversus abdominis
A
Linea alba
Pubic crest
Pectin pubis via conjoint tendon
21
Q
What is the rectus sheath
A
Tendinous sheath between the midclavicular line and the midline
Made up of the aponeuroses which are the anterior continuations of the flat muscles
It encloses the rectus abdominis
22
Q
How is the linea alba formed
A
Aponeuroses interweave with the aponeuroses of the opposite side
(There is also interweaving between layers on the same side)
23
Q
Where does the linea alba run from and to
A
Xiphoid process to pubic symphysis
24
Q
What is an ideal incision
Why can’t we sew muscles together
A
Can close and provide long lasting strength to reduce chance of incisional herniae
Sutures in a muscle will ‘cut out’ (like sewing butter)
25
What's a midline incision
Surgeons suture the linea Alba together
26
What's a transverse incision
Surgeons suture the external oblique aponeuroses together
27
Where is the incision for an appendicectomy
McBurney's point
28
Where is McBurney's point
2/3 distance from umbilicus to the ASIS
29
What is a gridiron incision
Put scissors in and open and close them to separate out the muscle fibres
3 stages because 3 layers of muscle (3 different fibre directions)
30
What is somatic referred pain
Pain caused by a noxious stimulus to the proximal part of a somatic nerve that is perceived in the distal dermatome of the nerve
E.g herpes zoster
31
What is visceral referred pain
Pain caused by ischaemia, abnormally strong muscle contraction, inflammation or stretch
It is referred to dermatomes of the spinal ganglia providing the sensory fibres
32
What is the course of visceral afferent pain fibres in the thorax and abdomen
Follow sympathetic fibres back to the same segment of the spinal cord that give rise to the preganglionic sympathetic fibres
33
Where is foregut pain felt
Epigastric region
34
Where is midgut pain felt
Periumbilical region
35
Where is hindgut pain felt
Suprapubic region
36
Where is early appendicitis pain felt
Umbilicus
| Innervation of the appendix enters the spine at T10
37
Where is late appendicitis pain felt
Right lower quadrant
| Becomes more inflamed and and irritates the surrounding bowel wall
38
What causes referred diaphragmatic irritation
Ruptured spleen
Ectopic pregnancy
Perforated ulcer
39
Describe referred diaphragmatic irritation
Blood pools in pelvis giving pain
Loss of blood makes patient faint so lies down causing blood to rush up to the diaphragm (C3-5)
This leads to referred pain in the left shoulder
No pain in right shoulder because the liver is in the way of the blood at the right diaphragm
40
What is the peritoneal cavity
A potential space of capillary thinness between the parietal and visceral layers of peritoneum containing a thin film of peritoneal fluid
41
What absorbs peritoneal fluid
Lymphatic vessels
| Particularly on the interior surface of the diaphragm
42
What difference is there between males and females in the peritoneal cavity
Males - completely closed
Females - there's a communication with the exterior of the body through uterine tubes, the uterus and vagina (infection from exterior)
43
What is the peritoneum
Continuous 2 layers membrane:
Parietal - lines the internal surface at the abdominal wall
Visceral - invests viscera
44
What separates parietal peritoneum from the abdominal muscles
Extraperitoneal connective tissue
45
What attaches the parietal peritoneum to the anterior abdominal and pelvis walls
Why is this
Loose CT
| Allows bladder and rectum to enlarge
46
Describe how the extraperitoneal tissue differs depending on location
Behind the linea alba and on the inferior surface of the diaphragm it is denser and more firmly adherent
47
What's the blood, lymphatic and somatic nerve supply of the parietal peritoneum
Same as the region of the wall it lines
48
What's the blood, lymphatic and visceral nerve supply of the visceral peritoneum
Same as the organ it covers
49
What sensations is parietal peritoneum sensitive to
Pressure
Pain
Heat
Laceration
50
Is pain of parietal peritoneum well or poorly localised
| What's the exception
Well
| Diaphragm (referred pain to shoulder)
51
What innervated the diaphragm
Phrenic nerve
52
What sensations is visceral peritoneum sensitive to
Stretching
| Chemical irritation
53
Is pain of visceral peritoneum well or poorly localised
Poorly
54
What is mesentery
Double layer of peritoneum occurring as a result invagination of the peritoneum by an organ
It connects intraperitoneal organs to the body wall
55
What's a peritoneal ligament
Double layer of peritoneum that connects an organ with another organ/to the abdominal wall
56
What peritoneal ligaments are attached to the liver
Falciform ligament (liver to anterior abdominal wall)
Hepatogastric ligament
Hepatoduodenal ligament
57
What peritoneal ligaments are attached to the stomach
```
Gastrosplenic ligament
Gastrophrenic ligament (stomach to inferior surface of diaphragm)
Gastrocolic ligament (stomach to transverse colon)
```
58
What are bare areas
They allow entrance and exit of neurovascular structures in organs
59
What are intraperitoneal organs
Organs completely covered by peritoneum
60
What are retroperitoneal organs
Organs outside of the peritoneal cavity and so are only covered partially by parietal peritoneum
61
What are subperitoneal organs
Organs beneath the peritoneum in the subperitoneal space
| E.g bladder and lower third of the rectum
62
What lines are used to divide the abdomen
Vertically - midclavicular lines
| Horizontally - subcostal line and transtubercular line
63
What are the 9 regions of the abdomen from left to right (superior to inferior)
```
Left hypochondriac
Epigastric
Right hypochondriac
Left lumbar
Umbilical
Right lumbar
Left iliac
Hypogastric
Right iliac
```
64
What does the transverse mesocolon divide the abdominal cavity into
Supracolic
| Infracolic
65
What does the supracolic compartment contain
Stomach
Liver
Spleen
66
What does the infracolic compartment contain
Small intestine
Ascending colon
Descending colon
67
Where does the infracolic compartment lie
Posterior to the greater omentum
68
How is the infracolic compartment divided
Left and right infracolic spaces by the mesentery of the small intestine
69
How do the supracolic and infracolic compartments communicate
Paracolic gutters
70
Where are the paracolic gutters
Grooves between the lateral aspect of the ascending or descending colon and the posterolateral abdominal wall
71
What is the greater peritoneal sac made up of
Supracolic and infracolic compartments
72
Other name for the lesser peritoneal sac
Omental bursa
73
What limits the superior recess of the lesser sac
Diaphragm
| Posterior layers of the coronary ligament of the liver
74
Where is the inferior recess of the lesser sac
Between the superior parts of the layers of the greater omentum
75
How does the inferior recess of the lesser sac change with age
Most of the inferior recess becomes sealed off from the main part (part posterior to stomach) after adhesion of the anterior and posterior layers of the greater omentum
76
What does the lesser sac permit
Free movement of the stomach on the structures anterior and posterior to it
77
How do the greater and lesser sacs communicate
Through the omental/epiploic foramen
78
How is the omental foramen located
Running a finger along the gall bladder to free the edge of the lesser omentum (hepatoduodenal ligament)
The opening admits 2 fingers
79
Where is the right subphrenic space
Between the diaphragm and anterior, superior and right lateral surfaces of the right lobe of the liver
80
How is the right subphrenic space bound on the left side
By the falciform ligament
81
How is the right subphrenic space bound on the posterior side
By the upper layer of the coronary ligament
82
Where does fluid usually collect after right sided abdominal inflammation
In the right subphrenic space
83
Where is the left subphrenic space
Between the diaphragm, the anterior and superior surfaces of the left lobe of the liver, the anterosuperior surface of the stomach and the diaphragmatic surface of the spleen
84
How is the left subphrenic space bound on the right side
By the falciform ligament
85
How is the left subphrenic space bound on the posterior side
By the anterior layer of the left triangular ligament
86
Where does fluid usually collect after a splenectomy
Left subphrenic space
87
Which subphrenic space is larger
Left (because liver is on the right)
88
Describe the recto-uterine pouch (of Douglas)
Pouch created between the rectum and uterus by a peritoneal fold
The recto-uterine fold of peritoneum passes from the rectum to the posterior vaginal fornix and back to the uterine cervix and body
89
Describe the vesico-uterine pouch
Shallow pouch created between the uterus and the bladder by a peritoneal fold
The peritoneum passes from the uterine fundus to the junction of the uterine body and cervix. Then it is reflected to the upper surface of the bladder
90
Describe the recto-vesicle pouch
Pouch created between the rectum and bladder by a peritoneal fold
The peritoneum passes from the junction of the middle and lower thirds of the rectum to the super aspect of the bladder
91
What does the mesentery of the small intestine connect
Jejunum and ileum to the posterior abdominal wall
92
What's between the layers of peritoneum of the mesentery of the small intestine
Blood vessels, lymph vessels and nerves
93
What is the root of mesentery of the small intestine
Attached parietal border
Starts 15cm from the duodenojejunal flexure at the level of L2
Ends at the ileoceacal junction
94
What does the root of mesentery of the small intestine cross
```
2nd and 3rd parts of the duodenum
Abdominal aorta
Inferior vena cava
Right ureter
Right psoas major
Right gonadal artery
```
95
What does the sigmoid mesocolon connect
Sigmoid colon to the pelvic wall
96
Where is the apex of the (inverted V-shaped) root of the sigmoid mesocolon
Superior to the division of the left common iliac artery
97
Where does the lateral/left limb of sigmoid mesocolon descend
Medial to left psoas major
98
Where does the medial/right limb of sigmoid mesocolon pass
Into the pelvis and ends in the midline at S3
99
What runs between the layers of the sigmoid mesocolon
Sigmoid and superior rectal vessels
100
What descends posterior to the apex of the root of sigmoid mesocolon
Left ureter
101
What does peritoneal fluid consist of
Water
Electrolytes
Leukocytes
Antibodies
102
Functions of peritoneal fluid
Acts as a lubricant to allow free movement of abdominal viscera
Antibodies fight infection
103
What is ascites
Accumulation of excess fluid in the peritoneal cavity
104
Why is peritonitis resulting from infections of the vagina, uterus and uterine tubes rare
Presence of a mucous plug in the external opening of the uterus
105
What does the mucous plug in he external uterus opening do
Prevents passage of pathogens but allows passage of sperm
106
What is culdocentesis
Extraction of fluid from the recto uterine pouch through a needle inserted through the posterior fornix of the vagina
107
What is paracentesis
Drainage of fluid from the peritoneal cavity through a needle inserted through the anterolateral abdominal wall
Used to drain ascitic fluid, diagnosis of cause of ascites, check for cancers which metastasise via the peritoneum
108
Most common cause of ascites
Portal hypertension secondary to cirrhosis of the liver
109
Less common causes of ascites
Malignancies of GI tract,
Malnutrition,
Peritonitis,
Internal bleeding
110
How does ascites present
Distended abdomen
Discomfort
Nausea
Dyspnea (SOB)
111
Why are patients with ascites positioned in a sitting position (at least 45 degree angle)
Encourages ascitic fluid to flow into pelvis instead of through paracolic gutters
In the pelvis toxins are absorbed much slower
112
Causes of peritonitis
Bacterial contamination:
during a laparotomy (open surgical incision of peritoneum)
Secondary to an infection in the GI tract e.g burst appendix, acute pancreatitis
113
Presentation of peritonitis
```
Pain and tenderness of overlying skin
Anterolateral abdominal muscles contract to protect viscera (guarding) - patients may flex knees in an attempt to relax the anterolateral abdominal muscles
Fever
Nausea
Vomiting
Constipation
```
114
Major risk of generalised peritonitis
Sepsis
115
Purpose of tendinous intersections of rectus abdominis
To make rectus abdominis more efficient (very long muscle)
116
How does the greater omentum have a function in infection
Walls off infection from the rest of the body so an abscess is formed in the peritoneum
117
Difference of the rectus sheath above and below arcuate line
Below arcuate line there is no posterior part of the rectus sheath (rectus abdominis is not enclosed in sheath)
118
Signs of a rectus sheath haematoma
Bruising on the abdomen
| Severe pain when using rectus abdominis muscles
119
Where are the loins
Junction of ribs and paravertebral muscles
120
Why is shingles often mistaken for appendicitis
Pain in supra public region (T12) occurs before rash forms
