Abdomen Flashcards
Abdominal surface anatomy: demonstrate the bony and cartilaginous landmarks of the abdomen and surface projections of the abdominal organs, demonstrate the descriptive regions of the abdomen Abdominal wall: describe the anatomy, innervation and functions of the muscles of the anterior, lateral and posterior abdominal walls. Explain their functional relationship with thoracic and pelvic diaphragms, and their roles in posture, ventilation and voiding of abdominal/pelvic/thoracic contents Inguina (209 cards)
1
Q
What is the anatomy of the pelvic girdle? What are the three main parts that make it up?
A
Made up of the pelvis, sacrum and coccyx. Iliac crest, iliac fossa, anterior superior iliac spine (ASIS). Pubic symphysis, pubic tubercle, superior pubic ramus.
2
Q
How is the abdominopelvic cavity defined?
A
Shown in pink (abdominal cavity) and green (pelvic cavity). Abdominal cavity partly overlaps into the thoracic region. Pelvic cavity is backwards and downwards. Abdominal and thoracic cavity separated by the diaphragm. The pelvic inlet (pelvic brim) arbitrarily separates the abdominal from the pelvic cavity, though the abdominal and pelvic cavities are both CONTINUOUS.
3
Q
What is the pelvic brim?
A
Photo
4
Q
What visceral structures are found in the abdomen?
A
Stomach, duodenum, small and large intestines. Liver, pancreas, spleen. Kidneys, ureters and urinary bladder. Reproductive organs. Abdominal vessels.
5
Q
What are the 9 regions of the anterior abdominal wall?
A
Photo.
6
Q
What is the alternative name for iliac region?
A
Groin region.
7
Q
What is the alternative name for lumbar region?
A
Flank region.
8
Q
What are the 4 regions of the anterior abdominal wall?
A
Right upper quadrant, left upper quadrant, left lower quadrant, right lower quadrant.
9
Q
How is the anterior abdominal wall divided into four regions?
A
Midline through the sagittal plane. Horizontal line called the trans-umbilical plane which runs through the umbilicus.
10
Q
What organs are found in each of the four abdominal quadrants? (x2 for each)
A
RIGHT UPPER: liver and gallbladder. LEFT UPPER: stomach and spleen. RIGHT LOWER: cecum and appendix. LEFT LOWER: end of the descending colon and sigmoid colon.
11
Q
What is the surface anatomy of the appendix?
A
The McBurney’s point which is 1/3rd of the way along a line from the right anterior superior iliac spine to the umbilicus.
12
Q
What are the posterior abdominal wall muscles? (x6) Functions of the two major muscle groups?
A
PSOAS MAJOR: attachments to the bodies and discs of the lumbar vertebrae and lesser trochanter of femur (they are the FLEXORS of the hip and trunk). ILIAC MUSCLE: found inferior to the iliac crest. QUADRATUS LUMBORUM: attachments to the lower border of the 12th rib and transverse process of the 5th lumbar vertebrae and adjacent iliac crest. Stabilises the 12th rib and a lateral flexor of the trunk. TRANSVERSE ABDOMINUS. DIAPHRAGM. AND…ERECTOR SPINAE MUSCLES: found posteriorly to the vertebral column.
13
Q
Lateral layers: Three flat-sheet muscles.
A
External obliques. Internal obliques. Transversus abdominus (or innermost). All separated by their own fascia. Contribute to the recuts sheath.
14
Q
What are the functions of the three flank sheet muscles? (x3)
A
This describes the obliques and transversus abdominus. 1. Compress the abdomen and increase the intra-abdominal pressure to aid expiration (most important muscles in forces expiration), and evacuation of urine, faeces, parturition (childbirth) and heavy lifting. 2. Supports the viscera – “guarding” mainly the intestines. 3. Flex and rotate the trunk.
15
Q
What are the attachments of the external obliques?
A
Attached to: (1) external surface of lower 8 ribs; (2) free posterior border (no attachments at all); (3) fans out to attach to xiphoid process, linea alba, pubic crest and tubercle, anterior half of iliac crest.
16
Q
What is the aponeurosis?
A
A sheet of pearly white fibrous tissue that acts as a tendon, having a wide area of attachment. What is the anatomy of the aponeurosis? (x2 points) Fuses medially with the rectus sheath. Fusion of the aponeurosis in the midline forms the linea alba. Lower aponeurotic edge is rolled inwards and forms the inguinal ligament (from ASIS to pubic tubercle).
17
Q
What is the rectus sheath?
A
A fascia formed by the aponeuroses of the transverse abdominal and the external and internal oblique muscles. Form in the middle to create the linea alba.
18
Q
How does the rectus sheath differ above and below the umbilicus?
A
ABOVE: internal oblique aponeurosis split and encloses the rectus abdominus (pink). The aponeurosis of external oblique (green) is in front and the transversus (blue) behind the rectus muscle. BELOW: all three aponeurosis layers are interior to the recuts muscle.
19
Q
What are the attachments of the internal obliques?
A
LATERALLY, there are attachments to the thoracolumbar fascia (connective tissue associated with posterior muscles), iliac crest (anterior 2/3rds) and the inguinal ligament (lateral half). MEDIALLY, there are attachments to the lower 3 ribs and costal cartilages, xiphoid process, rectus sheath and conjoint tendon.
20
Q
What is the conjoint tendon?
A
Lowest fibres of the internal oblique aponeurosis and similar fibres of the transversus abdominis aponeurosis join to form the conjoint tendon. Conjoint tendon attached medially to linea alba.
21
Q
What are the attachments of the transversus abdominus?
A
LATERALLY, there are attachments to the lower 6 costal cartilages, thoracolumbar fascia, iliac crest (anterior 2/3rd), inguinal ligament (lateral 1/3rd). MEDIALLY, there are attachments to the xiphoid process, linea alba (rectus sheath), symphysis pubis, conjoint tendon.
22
Q
Where does the neurovascular plane lie in relation to the three flank muscles?
A
Lies between the internal and transversus abdominis muscle layers.
23
Q
What directions to each of the three flanks point?
A
External obliques: downwards and forwards. Internal obliques: downwards and backwards. Transversus abdominus: directly horizontal.
24
Q
What are the attachments and relative positions of the rectus abdominus muscles?
A
Long strap muscle of the anterior abdominal wall enclosed in rectus sheath. SUPERIOR ATTACHMENTS: 5-7 costal cartilages and the xiphoid process. INFERIOR ATTACHMENTS: symphysis pubis and the pubic crest. How is the rectus abdominus divided? Divided into segments by tendinous intersections (3 pairs – one on each side of the linea alba) which are attached to the anterior wall of the rectus sheath.
25
What are semilunar lines? Surface anatomy?
Called linea semilunaris: curved tendinous intersection found on either side of the rectus abdominis muscle. Each corresponds with the lateral border of the rectus abdominis. It extends from the cartilage of the ninth rib to the pubic tubercle, and is formed by the aponeurosis of the internal oblique.
26
What is the epigastric fossa?
Slight depression in the midline just below the sternum (where a blow can affect the solar plexus).
27
What is the blood supply of the rectus muscle? (x2) Branches of what?
SUPERIOR EPIGASTRIC ARTERY – terminal branch of internal thoracic artery. INFERIOR EPIGASTRIC ARTERY – branch of external iliac artery. These two arteries enter the rectus sheath and anastomose, forming a potential by-pass to abdominal aorta.
28
What is the internal iliac artery?
Branch of the external iliac artery and supplies tissues in the pelvic region.
29
What is the blood supply of the flank muscles? (x4)
Intercostal arteries 7-11. Subcostal artery. Lumbar arteries. Deep circumflex iliac arteries.
30
What regions of the dermatome are sensory to each of the 9 regions of the anterior abdominal wall?
Epigastric row = T7. Umbilicus region = T10. Inguinal region = T12 (inguinal ligament = L1).
31
What is the somatic sensory supply of the parietal peritoneum and the visceral peritoneum?
PARIETAL: same segmental nerves of the body wall. VISCERAL: has NO somatic sensory innervation.
32
What are the motor nerve supply for the external obliques, internal obliques, transversus abdominus and the recuts abdominus?
EXTERNAL: T7-T11. INTERAL OBLIQUE AND TRANSVERSUS: T7-T12 and L1. RECTUS: T7-T12 (no L1).
33
What nerves supply the antero-lateral abdominal wall? (x3)
Subcostal nerve (T12), ilio-hypogastric and ilioinguinal nerves (L1).
34
What are the motor nerves that supply the quadratus lumborum, psoas major and iliacus?
Quadratus lumborum: T12-L4. Psoas: L2-L4. Iliacus: femoral nerves L2-L4. The lumbar plexuses are mainly for the LOWER LIMBS.
35
What is the transumbilical plane?
The horizontal plane that separates the abdominal wall above and below the umbilicus.
36
How is the superficial tissue of the abdomen lymphatically drained? Above and below the transumbilical plane?
Superficial lymphatics accompany subcutaneous veins. Lymphatic drainage happens in QUADRANTS.
ABOVE PLANE: to the pectoral group of axillary nodes. BELOW PLANE: to the superficial inguinal nodes.
37
How is the deeper abdominal tissue lymphatically drained? Above and below the transumbilical plane?
Deep lymphatics accompany deep veins in the extraperitoneal tissues. ABOVE PLANE: to the mediastinal nodes (found in mediastinum). BELOW PLANE: to the external iliac and para-aortic nodes (describes the associated veins).
38
What does the inguinal area describe? Anatomical landmarks that outline it?
The groin. The junction between the anterior abdominal wall and the thigh. Area is between the ASIS and the pubic tubercle.
39
What is the nature of the strength of the anterior abdominal wall in the inguinal region? Clinical AND anatomical importance?
Wall is WEAKENED in the inguinal region. CLINICAL IMPORTANCE: potential site of abdominal hernias. ANATOMICAL IMPORTANCE: structures exit and enter the abdominal cavity here e.g. spermatic cord, round ligament, vessels.
40
Hernia in the inguinal region is more common in which sex?
Males.
41
What is the anatomy of the inguinal region?
Pay attention only to the big labels.
42
What is the inguinal ligament made from?
Rolled inferior edge of the external oblique aponeurosis – between ASIS and pubic tubercle.
43
What is the anatomy of the inguinal CANAL?
Inguinal canal lies above the inguinal ligament and extends FROM deep inguinal ring (found in transversalis facia) to superficial inguinal ring (a hole in the external oblique aponeurosis, above and medial to the pubic tubercle).
44
What are the walls of the inguinal canal?
Not sure I need to concentrate on learning this. Seems quite obvious and bit unnecessary.
45
What are the two areas of particular weakness in the inguinal region?
INGUINAL CANAL and FEMORAL CANAL.
46
What passes through the inguinal and femoral canal? (for Inguinal, x2 for males, x1 for females, x1 for both sexes). (for Femoral, x2).
INGUINAL: testis and spermatic cord descend into the scrotum. In females, the uterine round ligament descends through the developing inguinal canal. Inguinal nerve passes through also, in both sexes. FEMORAL: below the inguinal ligament – femoral artery and vein passes.
47
What is a hernia?
Part or whole of an organ or tissue abnormally protrudes through the wall of the structure containing the organ or tissue.
48
What is the anatomy of a hernia in the abdomen?
Hernial sac is made from the skin on the outside, abdominal wall and more internally, the peritoneum.
49
What are the signs of hernia? (x4) – very general.
1. Lump or protrusion of groin. 2. Painless/painful and uncomfortable. 3. May be reducible or irreducible. 4. May be strangulated with tissue death and associated with vomiting, constipation, intestinal obstruction (this is an emergency situation).
50
What – out of inguinal or femoral hernias – are most common?
Inguinal.
51
What are the two types of inguinal hernia?
Indirect and direct.
52
Out of direct and indirect inguinal hernia, which is most common?
Indirect.
53
What are direct and indirect inguinal hernias?
DIRECT: defects go through Hesselbach’s Triangle (inguinal triangle), which is always MEDIAL to the inferior epigastric vessels, pushing through peritoneum and transversalis fascia of the POSTERIOR WALL of the inguinal canal.
INDIRECT: defects go through the internal (aka deep) ring which is LATERAL to the inferior epigastric vessels i.e. indirect path through the abdominal wall. Once it enters the deep ring, it passes through the inguinal canal, external inguinal ring and into the scrotum.
54
What are the causes of direct inguinal hernia? (x3)
1. Older age. 2. Chronic straining. 3. Weak musculature.
55
What are the causes of indirect inguinal hernia? (x1)
Tends to be in younger adults and children.
56
Epidemiology of femoral hernias? (x2 points)
More common in elderly and females.
57
What are the borders of the femoral canal?
SUPERIOR: inguinal ligament. INFERIOR: pectineus fascia. MEDIAL: lacunar ligament. LATERAL: femoral vein.
58
What are the signs of femoral hernia? (x3)
Irreducible, hot and painful.
59
How can inguinal and femoral hernias be differentiated?
Femoral hernias appear BELOW and LATERAL to the pubic tubercle. Inguinal hernias appear ABOVE and MEDIAL to the pubic tubercle.
60
What are the two causes of hernia?
CONGENITAL and ACQUIRED.
61
What is a congenital hernia?
The descent of the testes requires the processus vaginalis, which is a finger-like projection of parietal peritoneum. This fetal structure normally closes, however, a persistently patent (open) processus vaginalis is a ready-made indirect inguinal hernial sac.
62
What is an acquired hernia? (x1 and x3 causes)
Any cause of increased intra-abdominal pressure can be exploit a weak abdominal wall, whether the weakness is purely due to the inguinal canal or because there is weakening of tissue with age, fatty infiltration associated with obesity, or the increase in circulating elastases that have weaken abdominal musculature.
63
What are the two types of hernial treatment?
Conservative and surgical.
64
What is conservative treatment for hernia?
Identifying risk factor for hernia and treating them.
65
How are hernias resolved surgically?
Excise the hernial sac (to cut out), and the defect closed – sometimes with a polypropylene mesh. There should be no tension in the sealed wound.
66
What is the surface anatomy of the inguinal ligament?
Line between the pubic tubercle and the anterior superior iliac spine. The inguinal ligament creates a crease in the skin which creates the definitive ‘V-lines’.
67
How is the iliac tubercle palpated?
On skeleton, it is laterally projecting bony tip 5cm behind the ASIS – so, on your side. At the L5 level.
68
What is the surface anatomy of the ASIS?
Found at the S2 vertebral level and is the projection on the anterior region of the abdomen and quite lateral.
69
Difference between pubic symphysis and tubercle? And how to palpate?
Symphysis – cartilaginous joint that sits between and joins left and right pubic bones. Tubercle – forward-projecting tubercle on the upper border of the medial portion of the pubis. Can be felt in the pubic area.
70
What is the mid-inguinal point?
Mid-point of a line joining pubic symphysis and ASIS.
71
What is the trans-tubercular plane? Alternative name?
Horizontal plane at the L5 level. Also called the intertubercular plane. Goes through the RIGHT and LEFT ILIAC TUBERCLES.
72
What is the subcostal plane?
Horizontal plane across the right and left costal margins in the mid-axillary line i.e. the lowest edge of the 10th costal cartilage. At the L2/3 level.
73
What is the position of the umbilicus in relation to the lumbar curvature?
L3/4.
74
What is the transpyloric plane?
Horizontal plane at the level of the tips of the right and left 9th costal cartilages. At the L1 level.
75
What is the supra-cristal plane?
Horizontal plane through the highest point on the iliac crest. Passes at the L4 level.
76
How is anterior abdominal wall divided into 9 regions?
MID-CLAVICULAR PLANES: vertical lines are drawn from the mid-clavicular to mid-inguinal points on each side. SUBCOSTAL PLANE: horizontal line joining the right and left costal margins in the mid-axillary lines. INTERTUBERCULAR PLANE: goes through right and left iliac tubercles.
77
How laterally do the rectus abdominus extend in the anterior abdominal wall?
Most lateral part touches the mid-clavicular plane.
78
What is the PSIS? Surface anatomy?
Posterior superior iliac spine found at the S2 level. It is directly posterior to the ASIS and marks the middle of the sacroiliac joint. At the surface, both PSIS are found as depressions of skin just above the buttocks.
79
What is a sacral dimple?
Found at the S2 level, and a prominent dimple found on the midline above the buttocks. It is a defect found in a small proportion of the population.
80
What is the sacroiliac joint?
The joint between the sacrum and the pelvis.
81
Describe the Peritoneum
•Lines the abdominal cavity.
•SINGLE continuous membrane of simple SQUAMOUS epithelium – MESOTHELIUM.
82
What is the peritoneal cavity
* The peritoneal cavity is a POTENTIAL space within the layer of peritoneum.
* Components of the GI tract are suspended in peritoneal reflections – MESENTERIES.
83
Viscera in the thoracic cage
Liver, Gall Bladder, Transverse Colon, Stomach, Spleen
84
Viscera within pelvic cavity
Rectum
85
Describe embryology of formation of the Gut tube
The gut tube originates from the endoderm and splanchnic mesoderm (splanchnic Gr.= pertaining to visceral organ)
It is suspended from the posterior abdominal wall by a peritoneal fold – the dorsal mesentery
86
Intra Peritoneal contents?
Defines organs that are INSIDE the peritoneal cavity.
Most of small intestine, large intestine, Liver, stomach
87
Retro peritoneal cavity contents
DEFINES ORGANS IN THE ABDOMEN THAT ARE NOT INSIDE THE PERITONEAL CAVITY. MOST ARE FOUND IN THE POSTERIOR ABDOMINAL WALL.
–Kidneys & ureters
–Suprarenal glands
–Aorta/Inferior vena cava
–Nerves: lumbar plexus, sympathetic trunk
–Oesophagus
–Rectum
–Duodenum (except the first part) \*
–Pancreas (tail is INTRAperitoneal) \*
–Colon (ascending and descending only)\*
\* These organs originally had a mesentery, then became secondarily retroperitoneal when the mesentery fused with the body wall
88
What are the divisions of the peritoneal cavity?
GREATER SAC and OMENTAL BURSA (lesser sac).
* GREATER SAC: Shaded in brown in photo.
* OMENTAL BURSA: posterior to the stomach and liver and is CONTINUOUS with the greater sac through the omental foramen.
89
Divisions of the gut x3
* FOREGUT – Distal 3rd of oesophagus to the 2nd part of the duodenum at the entrance of the bile duct (Major duodenal papilla).
* MIDGUT – 2nd part of the duodenum to two-thirds along transverse colon.
* HINDGUT – Distal third of transverse colon to the rectum.
90
What are the mesentaries
* Peritoneal folds attaching viscera to the abdominal wall.
* Conduit for VESSELS, NERVES and LYMPHATICS supplying viscera.
* VISCERAL peritoneum – covering the suspended organs
* PARIETAL peritoneum – lines the abdominal wall.
91
Dorsal and Ventral Mesenteries
* The ENTIRE gut tube is suspended from a DORSAL (posterior) mesentery
* The VENTRAL (anterior) mesentry suspends the foregut (oesophagus, stomach and first half of the duodenum), and CONTAINS the liver, splitting into the FALCIFORM LIGAMENT and LESSER OMENTUM.
92
Formation of lesser sac (Omental bursa)
As the liver grows, it moves to the right while the dorsal mesentery and spleen move to the left. So, the original right side of the upper peritoneal cavity is now posterior – this area is called the lesser sac of the peritoneal cavity.
The image has a weird orientation - the top 'sac' is the RIGHT side of the body. The right side of the image is the POSTERIOR end of the body.
93
Describe the attatchments of the Greater and Lesser mesentry and the Omental Foramen
The lower part of the dorsal foregut mesentery extends down as a double fold called the greater omentum anterior to the intestine. The lesser omentum is part of the ventral foregut mesentery.
The greater omentum attatches to greater curvature of the stomach and first part of the duodenum. It drapes inferiorally over the transverse colon, turns posteriorally, ascends and attatches to the peritoneum on the superior surface of the transverse colon, before arriving at the posterior abdominal wall.
The lesser omentum extends from the lesser curvature of the stomach and first part of duodenum to the inferior surface of the liver. Formed of a hepatogastric ligament and a hepatoduodenal ligament (which acts as a border for the foramen omental). Enclosed within the hepatoduodenal ligament are the hepatic artery, bile duct and portal vein.
94
What direction foes peritoneal fluid flow?
Towards the diaphragm
95
What direction does inflammatory fluid and exudate flow?
Towards the colon via the right and left paracolic guttur
96
Layers of the GI tract Inner -\> Outer
Lumen
Mucosa: Epithelium, Lamina Propia, Muscularis Mucosa
Muscularis: Circular, Longutidinal
Serosa: Connective tissue
Mesentery
97
What is the superior vertebral and inferior vertebral notch?
photo
98
What are the two main part of the vertebral disc?
Anulus fibrosus (outer ring of collagen surrounding a wider ring of fibrocartilage – arrangement limits rotation between vertebrae) and nucleus pulposus (gelatinous and absorbs compression forces).
99
What is a posterolateral herniation of the intervertebral disc?
Degenerative changes/tear in the anulus fibrosus can lead to herniation of the nucleus pulposus. This usually happens posterior-laterally = can impinge on the ROOTS of a spinal nerve in the intervertebral foramen.
100
Where might a patient be expected to perceive pain as a result of injuries with (i) posterolateral herniation and (ii) posterior herniation of the intervertebral discs?
??? Can’t find answer but my guess is…
POSTERIOR = pain in the back and lower limbs because posterior herniation directly presses on the spinal cord, so pain is affected downstream.
POSTERIOR-LATERAL = pain the level of the back the herniation has occurred because herniation presses on spinal nerves, not cord.
101
How many vertebrae make up the sacrum? How are the bones fused?
The transverse processes have fused to form a large wing-like bony region on each side called the 5. The L5 can sometimes be sacralised with the sacrum.
102
Anatomy of the sacrum?
photo
103
What type of joint is the sacroiliac joint?
Synovial joint.
104
What are the four regions of the duodenum? Names of two points on the duodenum.
Superior part, descending part, inferior part, ascending part.
SUPERIOR PART = Duodenal cap.
DESCENDING PART = major duodenal papilla.
105
Where do most duodenal ulcers occur? Why?
Most occur at the duodenal cap because of greater exposure to stomach acid.
106
What is the major duodenal papilla?
Contains entrance for common bile duct.
107
Is the duodenum retroperitoneal or intraperitoneal?
Most of it retroperitoneal. Only a small part of the first part is intraperitoneal.
108
What is the difference between the diameters of the jejunum and ileum?
Jejunum is larger in diameter.
109
What is the difference between the mesenteries of the jejunum and ileum?
JEJUNUM: less prominent arterial arcades and longer vasa recta.
ILEUM: opposite.
110
What are the eight regions of the large intestine?
Vermiform Appendix. Cecum (pouch connecting to the junction of the large and small intestines). Ascending colon. Transverse colon. Descending colon, Sigmoid colon, rectum and anus.
111
What is the sigmoid colon?
Part of the large intestine closest to the rectum and anus.
112
What is the name of the hole that joins the small to the large intestine?
Ileocecal orifice.
113
What are the distinguishing features of the large intestine from the small intestine? (x3)
Fatty tags called appendices epiploicae, ribbons of longitudinal muscle called taeniae coli (there are three of these), and segmented, pocketed walls.
114
What is the blood supply to the gut? What does each artery supply?
COELIAC TRUNK (or axis): Foregut, liver, pancreas, spleen.
SUPERIOR MESENTRIC ARTERY: Midgut.
INFERIOR MESENTRIC ARTERY: hindgut.
These are UNPAIRED arteries arising from the anterior wall of the aorta.
REMEMBER their relative positions!
115
What is the anatomy of the coeliac trunk?
Left gastric – supplies the stomach.
Common hepatic artery – supplies the liver.
Splenic artery – supplies the spleen.
116
What structures are located behind the stomach?
Kidneys, pancreas, major vessels, bile duct, duodenum, spleen. The blood vessels that supply the gut all emerge posteriorly to the stomach and liver (because they originate from the aorta).
117
What are the branches of the superior mesenteric artery? (x5)
Middle colic artery supplies transverse colon.
Right colic artery supplies ascending colon.
Ileocolic artery supplies the distal part of the ileum and the cecum.
Jejunal arteries.
Ileal arteries.
118
What are the branches of the inferior mesenteric artery? (x3) At what point does the inferior mesenteric artery supply the colon, and the superior artery does not?
Left colic artery supplies the descending colon; sigmoid arteries supply the sigmoid colon; superior rectal arteries supply the rectum.
SUPERIOR --\> INFERIOR SUPPLY: junction of the mid- and hind-gut is near the left splenic flexure of the colon. There is a change from superior to inferior mesenteric artery supply at this level but with anastomoses between them.
119
How is the abdomen venously drained?
HEPATIC PORTAL VEIN arises from the SUPERIOR MESENTRIC and SPLENCHIC veins posterior to the 1st part of the duodenum/pylorus of the stomach. It then runs in the free edge of the lesser omentum to the liver. So, all abdominal visceral blood goes through the liver before the IVC.
120
What porto-systemic/caval anastomoses?
Portocaval anastomoses – where veins draining into the portal vein and vena cava (caval/systemic system) overlap.
121
Where are portacaval anastomoses found, and what veins are they associated with? (x5)
Found at each end of the GI system in the abdomen: at the INFERIOR END OF THE OESOPHAGUS, INFERIOR PART OF THE RECTUM, UMBILICUS, where LIVER IS IN DIRECT CONTACT WITH DIAPHRAGM, where the wall of the GI tract is in DIRECT CONTACT WITH THE POSTERIOR ABDOMINAL WALL.
122
What connects the umbilicus to the rest of the venous system? (x2 names)
ROUND LIGAMENT OF THE LIVER aka PARAUMBILICAL VEIN. Connects umbilicus to the left branch of the hepatic portal vein as it enters the liver.
123
What happens when there is a blockage of the hepatic portal vein or of vascular channels in the liver?
Can slow/stop venous return from GI tract in the abdomen. The portacaval anastomoses therefore enlarge and become twisted among each other allowing blood in the tributaries (branches) of the portal system to bypass the liver, enter the caval system and thereby return to the heart. Possibly leading to severe venous haemorrhage from OESOPHAGUS or RECTUM. Systemic vessels that radiate from para-umbilical veins enlarge and become visible on the abdominal wall – CALLED CAPUT MEDUSAE.
124
What vessels does the lymphatic drainage of the peritoneal cavity follow?
Arteries – NOT veins.
125
How is the peritoneal space lymphatically drained? (x3 nodes)
INFERIOR MESENTRIC NODES, SUPERIOR MESENTRIC NODES, COELIAC NODES – found at their respective arteries (in front of the aorta). All lymph drains into the CISTERNA CHYLI which is an elongated lymphatic sac located in front of the L1 & L2 bodies. The thoracic duct commences from this cisterna.
126
How is the gut innervated? (x2 and x4) What nerves are most important? Function of each nerve? Origins of each nerve?
Abdominal viscera supplied by the AUTONOMIC NERVOUS SYSTEM – SENSORY FIBRES are most important.
Parasympathetic sensory: regulate reflex gut function – vagus nerve (cranial nerve X) and pelvic splanchnic nerves (S2-4).
Sympathetic sensory: mediate pain – greater thoracic splanchnic (T5-9), lesser thoracic splanchnic (T10-11), least thoracic splanchnic (T12) and lumbar splanchnic (L1&2).
LEAST SPLANCHNIC NERVE (from the T12 level) and nerves from the LUMBAR SYMPATHETIC CHAIN all originate BELOW the diaphragm.
The greater and lesser splanchnic nerves emerge from their vertebrae and move across the abdomen and into the diaphragm where they innervate the abdominal viscera.
127
What are primary retroperitoneal structures?
Structures that develop outside the parietal peritoneum. They never had a mesentery.
128
What examples are there of primary retroperitoneal structures?
Abdominal aorta, IVC, kidneys, ureters, adrenal glands, lumber plexus and sympathetic trunk.
129
What are the anatomical relations of the four regions of the duodenum?
FIRST PART: first 2cm has a mesentery and lies anterior to the bile duct. L1 level.
SECOND PART: bile duct and pancreatic ducts open into it. Root of transverse mesocolon crosses it. L1-L3 level.
THRID PART: crossed anteriorly by the superior mesenteric artery and vein. L3 level.
FOURTH PART: leads to jejunum. L2 level.
130
Is the spleen retroperitoneal?
no
131
What are the anatomical relations of the duodenum, pancreas, kidneys, spleen and vertebrae?
photo
132
Where does the tail of the pancreas reside?
Intraperitoneally. Extends from the kidney to the spleen in the dorsal foregut mesentery.
133
LEARN TO DRAW THE FOLLOWING INCLUDING THE BLOOD SUPPLY:
photo
134
What is the blood supply of the adrenal glands?
Superior suprarenal, middle suprarenal and inferior suprarenal arteries.
135
What is the venous drainage of the adrenal glands?
Arterially supplied by three vessels, but there’s only one venous vessel – the suprarenal veins Left drains into the renal vein and then the IVC or Right directly into the VC
136
What are the visceral relations of the kidneys?
RIGHT: liver, small intestine, descending part of duodenum.
LEFT: stomach, spleen, tail of the pancreas, jejunum.
Adrenal glands are on both sides (suprarenal glands).
137
What is the relationship in position between the two kidneys? RECAP FROM URINARY SYSTEM!
Right lower than left because the liver pushes the right down; upper poles closer to median plane than lower poles.
138
What horizontal position do the hilum lie?
Transpyloric plane. L1 plane.
139
Where are the three narrowings of the ureters?
1. Ureteropelvic junction.
2. Pelvic brim.
3. Entrance of urinary bladder.
140
What is the significance of ureter narrowings?
Most common sites that kidney stones become stuck.
141
How are kidneys accessed for surgery? Why – what is found posteriorly? (x3 nerves)
Posteriorly – because unlike anteriorly where there are lots of organs in the way, posterior access means that only muscles and nerves must be transversed.
THE NERVES ARE: Subcostal (T12 nerve), ilio-hypogastric and ilio-inguinal nerves (L1 nerves).
142
What are the mesenteries in relation to the stomach, liver and spleen? (x4)
Falciform ligament.
Lesser omentum.
Gastrosplenic ligament.
Splenorenal ligament.
143
How does the liver sit in the abdomen in situ?
photo
144
What is the ‘diaphragmatic’ and ‘visceral’ surface of the liver? Coverings of the diaphragmatic surface?
Diaphragmatic is the ANTERIOR-SUPERIOR SURFACE (bottom photo). The superior-posterior aspect is NOT covered in visceral peritoneum and instead in direct contact with the diaphragm.
Visceral is the POSTERIOR-INFERIOR SURFACE (top photo). With exception to the fossa (shallow depression) of the gall bladder and porta hepatis, it is covered in peritoneum.
145
The liver visceral surface: what anatomical relations are there to this surface?
Bare area marked in red.
Beige areas indicate a visceral structure.
146
What are the ligaments of the liver? (x4) Attachments of each?
1. FALCIFORM LIGAMENT – attaches anterior surface of the liver to the abdominal wall.
2. CORONARY LIGAMENT – has anterior and posterior folds and attaches the superior surface of the liver to the inferior surface of the diaphragm.
3. LEFT AND RIGHT TRIANGULAR LIGAMENTS – attach their respective lobes to the diaphragm and formed by union of the anterior and posterior layers of the coronary ligament. Formed from the corners of the bare areas of the liver.
4. LESSER OMENTUM – attaches liver to lesser curvature of the stomach and first part of the duodenum.
147
What is the falciform ligament inferior attachment and prior purpose?
Called ligamentum teres and is the remnant of the umbilical vein.
148
What is the superior-posterior fissure called in the visceral surface of the liver? Origin?
Fissure for ligamentum venosum. Remnant of ductus venosus of the fetal circulation. NOT PART of the falciform ligament.
It may be continuous with the ligamentum teres (aka the round ligament) of the liver and is invested by the peritoneal folds of the lesser omentum.
149
What are the four lobes of the liver?
Superior, posterior edge = quadrate.
Inferior posterior edge = caudate.
Both quadrate and caudate are axillary lobes of the right lobe.
Right and left lobe separated by the falciform ligament.
150
What are the functional lobes of the liver?
Right vascular and left vascular lobe.
Based on the blood supply to regions of the liver.
MARKED BY THE INFERIOR VENA AND GALL BLADDER.
This means that the quadrate and caudate lobes now belong to the left vascular lobe.
151
What exception does the caudate lobe have in relation to vasculature?
Caudate lobe is functionally separate from the right and left lobes and has its own blood supply etc.
152
How does the IVC pass the liver?
It penetrate the liver from the superior, medial aspect and emerges more laterally and only slightly posteriorly. It does not penetrate for long.
153
What are the blood supplies of the right and left vascular lobes?
Right and left hepatic arteries.
154
How many liver segments are there?
8.
155
What are liver segments?
They have their own blood supply and bile duct branch.
156
Anatomically, how can the quadrate and caudate lobes be defined?
(x2)
```
Grooves for foetal veins mark out these lobes.
Porta hepatis (the deep fissure in the inferior surface of the liver through which all the neurovascular structures (hepatic artery, portal vein, common bile duct) except the hepatic veins enter and leave the liver – see photo –) separates quadrate and caudate superiorly and inferiorly.
```
157
What is the anatomical relation of the liver and stomach to the rest of the abdomen?
This is a very general question.
158
What is the anatomical relation of the liver in relation to the abdominal/thoracic wall?
Liver is covered under the ribs except in the upper epigastrium (exposed region below the xiphoid process).
159
What are the branches of the common hepatic artery? (x3)
INITIALLY BRANCHES INTO THE GASTRODUODENAL, RIGHT GASTRIC ARTERIES (supply the stomach), AND HEPARTIC ARTERY PROPER.
The hepatic artery proper is the ascending portion of the common hepatic artery which leads to the liver. This branches into the cystic artery (supplies gall bladder) and right and left branches.
REMEMBER THOUGH, MOST OF THE BLOOD SUPPLY COMES FROM THE HEPATIC PORTAL VEIN.
160
How does blood return to the IVC from the liver?
Once filtered, blood passes directly into the IVC via three short hepatic veins.
161
How do the pancreatic duct and bile duct drain into the duodenum? Sphincters? (x3)
Join to form the HEPATOPANCREATIC AMPULLA (OF VATER).
SPHINCTER OF ODDI guards the ampulla of Vater.
There are separate sphincters for the bile and pancreatic duct which are very near to the sphincter of Oddi.
162
How does the gall bladder and liver drain into the bile duct?
Cystic duct from gall bladder; right and left hepatic duct converge into common hepatic duct.
Both cystic and common hepatic duct join to form the common bile duct.
163
What is the major and minor papilla?
Major papilla = drainage from the bile duct and pancreatic duct.
Minor papilla = drainage from branch of the pancreatic duct.
164
What is the anatomical position of the common bile duct?
Passes behind the first part of the duodenum and head of pancreas to enter the second part of the duodenum at the major papilla – usually joining the major pancreatic duct.
165
What is the biliary tract?
Refers to the liver, gall bladder and bile ducts.
166
What are the different parts of the gall bladder?
Fundus, body and neck --\> cystic duct.
167
What are the anatomical relations of the gall bladder?
First part of the duodenum, transverse colon, anterior abdominal wall.
168
How is the spleen suspended in the abdomen?
Suspended in the dorsal foregut mesentery.
What is the anatomical relation of the spleen to the ribcage?
Lies posteriorly on L side under ribs 9-11.
169
By what ligaments, is the spleen suspended in the dorsal foregut mesentery? What is the function of both ligaments?
By the gastro-splenic and lieno-renal (or splenorenal) ligaments (highlighted in the blue boxes).
SPLENORENAL LIGAMENT – contains the tail of the pancreas and splenic artery.
GASTROSPLENIC LIGAMENT – carries blood vessels from the splenic artery to the left side of the stomach – called short gastric vessels.
They are both part of the GREAT OMENTUM. Blood vessels to the spleen enter through these ligaments.
170
What are the surfaces of the hilar surface of the spleen? (x3)
Superior and inferior borders; anterior extremity.
171
What are the anatomical relations of the hilar surface of the spleen? (x4)
Stomach lies at the superior region of the spleen.
Left kidney at the inferior border.
Colon at the anterior extremity.
Splenorenal ligament houses the tail of the pancreas also.
172
What is the surface anatomy of the liver?
IT HAS THREE BORDERS:
* UPPER BORDER: closely follows the diaphragm. In mid-inspiration, the upper border is marked by a line from the right 5th rib and costal cartilage (point 1) which extends across the lower end of the sternum (point 2) to the left 5th intercostal space in the mid-clavicular line (point 3).
* OBLQUE/LOWER BORDER: the oblique border follows the right costal margin from the mid-axillary line (point 4) through the tip of right 9th costal cartilage (lies at the junction of costal margin and lateral border of rectus abdominis) to the tip of the left 8th costal cartilage to the left 5th intercostal space in the midclavicular line.
* RIGHT BORDER: starts from point 4 and ascends upwards along the right margin of the thoracic cage to meet point 1 on the right 5th rib.
173
What is the surface anatomy of the gall bladder?
Where the transpyloric plane meets the mid-clavicular line – which is at the tip of the right 9th costal cartilage or where the lateral border of the rectus abdominis crosses the costal margin.
174
What is the surface anatomy of the spleen?
Lies along the left 9th, 10th and 11th ribs between the erector spinae muscles and the mid-axillary line.
1. Palpate and surface mark the 10th rib.
2. Palpate and surface mark the 9th rib.
3. Surface mark the lateral border of erector spinae and mid-axillary line.
4. Draw the spleen outline with its long axis along ribs 9, 10 and 11.
175
What are the four elements of the abdominal physical examination and what happens in each?
1. INSPECTION: make notes on shape of abdomen, skin abnormalities, surgical scars, masses, movement of abdominal wall with inspiration.
2. AUSCULTATION: this is done before palpation and percussion to NOT DISTURB the bowels. Apply the diaphragm of the stethoscope to the abdominal wall firmly.
BOWEL SOUNDS – listen systematically over all parts of the abdomen.
3. PALPATION: LIGHT PALPATION – in each region using fingertips. Palm of the hand moulding over the abdominal surface and the fingers flex at metacarpo-phalangeal joints.
DEEP PALPATION – place the hand flat and apply firm steady pressure. You may use both hands where upper hand applies pressure and lower hand is used to feel the organ or mass.
4. PERCUSSION: percussing the abdominal wall produces a hollow sound over air-filled spaces such as stomach and colon, but dull sound over solid organs such as the liver or spleen.
176
How do you perform a physical examination of the bodies of the lumbar vertebrae?
Press down firmly in midline of abdomen with pads of fingers.
177
How do you perform a physical examination of the pulse of the abdominal aorta?
Can be felt pulsing powerfully near the lumber vertebral bodies above the umbilicus just left of the midline – can also be seen if you apply pressure either side of the umbilicus.
178
How do you palpate the liver?
Depends on its downward movement when the subject takes a deep breath;
May be palpated in lean subjects by light pressure with the fingertips below the right anterior costal margin. As the subject breathes in deeply, you will feel the displacement of your fingers with by the anterior border of the liver as the diaphragm pushes it inferiorly.
179
How do you palpate the spleen?
Depends on its downward movement when the subject takes a deep breath;
Cannot be palpated if healthy. If enlarged three times normal size, it can be palpated below the left anterior costal margin.
180
How do you use percussion to define the extent of the liver?
Percussion from the mid-clavicular line to the costal margin. This will define the upper and lower borders of the liver.
Can also be done with the spleen and the kidneys.
181
What are the functions of the efferent nerves of the ANS to the abdomen? (x2)
Motor to smooth muscle and secretomotor to glands.
182
Branches of the aorta?
.
183
What are the functions of the afferent nerves of the ANS to the abdomen? (x2)
SYMPATHETIC: pain; PARASYMPATHETIC: specific function sensation e.g. stretch.
184
What does splanchnic mean?
Visceral.
185
What is the function of the greater, lesser and least splanchnic nerves?
Modulate the ENS.
186
How do the autonomic nerves run to the (i) peripheral vessels and skin and (ii) organs lacking somatic innervation of the abdomen?
(i) TO PERIPHERAL VESSELS AND SKIN: concerns only SYMPATHETIC NERVES – run with somatic nerves to the same region; (ii) TO ORGANS LACKING SOMATIC INNERVATION (hence why pain is not well-mapped in these areas): most run with the arteries to the same organs, and few run separately.
187
What is the pathway of the splanchnic nerves to the aorta?
Splanchnic nerves run from the thoracic vertebrae and travel through the diaphragm where they reach autonomic ganglia associated with the abdominal aorta. Here, the splanchnic nerves synapse into ganglia and contribute to plexuses which emerge from these ganglia.
188
What ganglia do the greater, lesser and least splanchnic nerves synapse into?
GREATER: celiac plexus (found near the celiac trunk); LESSER: superior mesenteric ganglia or aorticorenal ganglion; LEAST: renal ganglia.
189
How are the autonomic nerves of the abdomen arranged at their origins? Naming?
· The autonomic nerves to the abdomen are routed via plexuses surrounding the aorta and its branches.
· Sympathetic nerves synapse at ganglia associated with these plexuses.
· Plexuses and ganglia are named according to the associated blood vessels (e.g. coeliac plexus and ganglia, renal plexus and ganglia).
190
What are the abdominal plexus and ganglia of the autonomic nervous system?
The only nerve in the picture that is PNS is vagus nerve. The rest is SNS.
191
MORE DETAILED: what are the positions of the nerve plexuses and ganglia associated with the aorta?
After the ‘/’, the letter or number denotes the PNS supply to the same viscera.
192
What is the course of the nerves following the coeliac artery, superior mesenteric artery, inferior mesenteric artery, renal arteries, testicular/ovarian arteries, nerves to the suprarenal gland, and brances of the superior and inferior hypogastric plexuses? What do they supply?
* Nerves following Coeliac Artery: The artery immediately divides into 3 branches, the splenic artery, common hepatic artery and left gastric artery. Together nerves following these branches supply: lower end of oesophagus, stomach, spleen, liver and gall bladder, part of pancreas and part of duodenum.
* Nerves following Superior Mesenteric Artery: These nerves supply part of pancreas, part of duodenum, rest of small intestine, caecum and appendix, ascending colon, and part of transverse colon.
* Nerves following Inferior Mesenteric Artery: These nerves supply part of transverse colon, descending colon, sigmoid colon, part of rectum.
* Nerves following Renal Arteries: Supply kidneys and ureters
* Nerves following Testicular / Ovarian Arteries: Supply gonads
* Nerves to suprarenal gland: These nerves travel directly from the sympathetic chain or the coeliac plexus to the suprarenal gland. They are mostly preganglionic sympathetic fibres to the adrenal medulla (T6-L1)
* Branches of superior and inferior hypogastric plexuses: These nerves supply the bladder, part of rectum, ♀ uterus, ♀ part of vagina, ♂ ductus deferens, ♂ prostate and ♂ seminal vesicles.
193
What is the concept of referred pain?
* The cerebral cortex of the brain has no ‘sensory map’ for visceral organs and the diaphragm.
* Therefore, the brain cannot localise pain sensation from these structures.
* In these cases, pain is referred to the regions of skin supplied by nerves with the same segmental supply (dermatomes).
* In the abdomen, the nerve supply to the organs is autonomic.
194
What are dermatomes?
An area of skin supplied by a single spinal nerve.
195
What is the nature of adjacent dermatomes? Clinical application?
They overlap so that on the trunk, at least three spinal nerves would have to be blocked to produce a region of complete anaesthesia.
196
What is the only vertebral level that lacks a dermatome?
C1.
197
What are the sensory and motor maps of the cerebral cortex?
See photo – there is no mapping for visceral structures.
198
What is the position of the appendix in relation to the nine abdominal wall regions?
Found in the top right of the suprapubic region.
199
How is pain referred from the foregut structures? What vertebral level nerves does it concern?
Pain from the stomach, proximal duodenum, pancreas, liver and gall bladder (not all of the foregut structures) are referred to the epigastric region.
Concerns T7/T8 nerves.
200
What are the dermatomes of the abdominal wall?
.
201
How is pain referred from the midgut structures? What vertebral level is concerned?
Pain from midgut (duodenal papilla to splenic fixture) including inflamed appendix is referred to the PERIUMBILICAL REGION.
Afferent pain fibres from the midgut structures enter the spinal cord at T10 segment and skin of umbilical region is also supplied by T10 spinal nerve.
202
What does the pain of the umbilical region feel like when referred?
COLICKY (intermittent with bowel contractions).
203
How does pain in appendicitis progress?
Appendix is supplied by T10, so pain is initially referred to umbilical region. When the appendix becomes more inflamed, it begins to affect the surround peritoneum (abdominal wall), so the pain becomes localised and constant at the right inguinal region. Pain also turns from DULL, to SHARP and localised because pain becomes less central/visceral related.
204
How is pain referred from the hindgut structures? What vertebral level is concerned?
Pain from hindgut (from descending colon to the anal canal) is referred to the suprapubic region and concerns nerves from T12/L1/2 level.
205
Visceral Referred Pain?
Why is some of this different from before!?
206
What are the surface markings of the kidney?
Photo.
207
Artery, venous relations in the kidney hilum?
In the kidney hilum, the vein is anterior to the renal artery.
208
How do you palpate the kidneys?
Photo.
209
How is pain felt in kidneys?
Photo.
