Anatomy(The Abdomen, Pelvis and Perineum) Flashcards
Gut developed from what
Primitive endodermal tube
Parts of gut with blood supply
divided into three parts:
• foregut: extends to the entry of the bile duct into the
duodenum (supplied by the coeliac axis)
• midgut: extends to distal transverse colon (supplied by
superior mesenteric artery)
• hindgut: extends to ectodermal part of anal canal (sup-
plied by inferior mesenteric artery).
Rotation of stomach with vagus
Clockwise rotation seen from above
• Rotates so that the right wall of the stomach now
becomes its posterior surface, forming the lesser sac
behind.
• Vagus nerves rotate with the stomach so that the right
vagus nerve becomes posterior and the left anterior.
Peritoneal relation of duodenum
all retroperitoneal.except 1st inch
What is vitellointestinal duct
the vitelline duct, also known as the vitellointestinal duct, the yolk stalk, the omphaloenteric duct or the omphalomesenteric duct is a long narrow tube that joins the yolk sac to the midgut
yolk sac?
yolk sac is far more widely used. In humans, the yolk sac is important in early embryonic blood supply and much of it is incorporated into the primordial gut during the fourth week of embryonic development.
During development position change of caecum
The caecum descends into its definitive position in the
right iliac fossa, pulling the colon with it.
Relation of peritoneum with mesentery
•As the stomach rotates clockwise the duodenum
swings to the right, its mesentery fusing with the peri-
toneum of the posterior abdominal wall
•The mesenteries of the ascending and descending colon blend with the posterior abdominal wall, except for the
sigmoid colon, which retains a mesentery.
Mechanism of gut atresia or stenosis
In early fetal life, growth obliterates the lumen of the
developing gut. It then recanalizes. If recanalization is
incomplete, areas of atresia or stenosis may result.
What is Meckel’s diverticulum?
The communication between the primitive midgut and yolk sac may persist as a Meckel’s diverticulum attached to the back of the umbilicus by a fibrous cord, a remnant of the vitellointestinal duct (this may act as a fixed point for small bowel volvulus).
What is peritoneal band of Ladd
The caecum may also be free and may
obstruct the second part of the duodenum because of
peritoneal bands (of Ladd) passing across it. The base
of the mesentery is then very narrow as it is not fixed
at either end, and the whole of the midgut may twist
around its own blood supply, i.e. volvulus neonatorum.
*A peritoneal band of Ladd, also known as a Ladd’s band or mesenteric attachment, is a fibrous band of tissue that can form in the peritoneum during fetal intestinal rotation errors. The band can stretch from the caecum to the subhepatic region and usually attaches the caecum to the retroperitoneum in the right lower quadrant. Ladd’s bands are the most common type of peritoneal band that can cause intestinal malrotation.
What is exomphalos?
Persistence of midgut herniation at the umbilicus may
occur after birth
Exomphalos vs Gastroschisis
The prefix “ex-“ is a Latin word that means “out of,” “from
*Exomphalos/omphalocele
abdomen doesn’t close around the umbilical cord allowing organs to protrude into the the cord.
*Gastroschisis
defect in the abdominal wall to the side of the umbilical cord, usually the right side.
#The word omphalocele comes from the Greek words omphalos, which means “umbilicus”, and cele, which means “cavity”
#The word “gastroschisis” comes from the Greek words gastro, meaning “stomach”, and schisi, meaning “split”.
Function of urorectal septum
Urorectal septum divides the cloaca into bladder anteri-
orly and rectum (hindgut) posteriorly.
• At its caudal end, the urorectal septum reaches the cloa-
cal membrane and divides it into anal and urogenital
membranes.
• The anal membrane separates the hindgut from the
proctodeum (anal pit).
• Eventually the anal membrane breaks down and conti-
nuity is established between the anal pit and the hindgut.
• Failure of the anal membrane to rupture or anal pit to
develop results in imperforate anus.
Formation of anal canal
Anal canal develops from the end of the hindgut (endo-
derm) and an invagination of ectoderm, the proctodeum.
What is urachus
The connections between cloaca (rudimentary bladder) and allantois. The urachus is the embryonic remnant of this connection.
What is urachus
The connections between cloaca (rudimentary bladder) and allantois. The urachus is the embryonic remnant of this connection.
What gives off epididymis and vas
• Mesonephros develops at the 4th week; this also degenerates but its duct persists in the male to form the epididymis and vas deferens.
Metanephros gives off what
proximal part of the tubular system and glomeruli which are developing from the metanephros
Convention of metanephros and metanephric duct
• Metanephros develops at the 5th week in the pelvis.Metanephric duct arises as a diverticulum from the
lower end of the mesonephric duct.
• Metanephric duct (ureteric bud) invaginates the metanephros, undergoing repeated branching to develop into the ureter, pelvis, calyces and collecting tubules.
Migration of kidney
• The kidney develops in the pelvis, eventually migrating upwards, its blood supply moving cranially with it, initially being from the iliac arteries and eventually from the aorta.
What is ureteric bud
Metanephric duct
Mechanism of forming polycystic kidney
• Failure of fusion of the derivatives of the ureteric bud with the derivatives of the metanephros may give rise to autosomal recessive form of polycystic kidney.
Ureteric cause of urinary incontinence
• The ureteric bud may branch early, giving rise to double ureter. Rarely, the extra ureter may open ectopically into the vagina or urethra, resulting in urinary incontinence.
Primitive parts of urinary bladder
• Urinary bladder is formed partly from the cloaca and partly from the ends of the mesonephric ducts.
• The anterior part of the cloaca is divided into three parts:
• cephalic: vesicourethral
• middle: pelvic portion
• caudal: phallic portion.
• The latter two constitute the urogenital sinus.
• The ureter and mesonephric duct come to open separately into the vesicourethral portion. Lol
• The mesonephric duct participates in the formation of the trigone and dorsal wall of the prostatic urethra.
• The remainder of the vesicourethral portion forms the body of the bladder and part of the prostatic urethra.
• The apex of the bladder is prolonged to the umbilicus as the urachus (where the primitive bladder joins the allantois).
Function of allantois
It helps the embryo exchange gases and handle liquid waste.
Formation of urogenital sinus
Pelvic and phallic portion of anterior part of cloaca
Urorectal septum’s shape change
Fork to spoon
Terminal part of urorectal septum forms what
Perineal body
Cause of ectopia vesicae with cleft pelvis(no symphysis pubis) with Epispadias
Dorsal wall of the urethra is partially or completely absent and is caused by failure
of infraumbilical mesodermal development.
Development germ layer of testes
• Develops as a mesodermal ridge on the posterior abdominal wall medial to the mesonephros (urogenital ridges).
• Links with mesonephric duct, which forms the epididymis, vas deferens and ejaculatory ducts.
Mechanism of formation of hydrocele
• Processus vaginalis may fail to obliterate or may become partially obliterated, resulting in a variety of hydroceles
Layers of fascia on abdomen wall
Only superficial fascia
But 2 layers of it in the lower abdomen
Fatty camper
Fibrous scarpa
Extension of fascia of abdominal wall
• Superficial fascia extends onto penis and scrotum.
• Scarpa’s fascia is attached to the deep fascia of thigh 2.5 cm below the inguinal ligament.
• Extends into perineum as Colles’ fascia.
• Colles’ fascia is attached to the perineal body, perineal membrane and laterally to the rami of the pubis and ischium.
In which part of urethral injury urine tracks into the scrotum, perineum and penis and into abdominal wall deep to Scarpa’s fascia
In rupture of the bulbous urethra
Like hydrocele of the cord in male what is a similar lesion exists in the female?
hydrocele of the canal of Nuck
Origin and insertion of rectus abdominis
• Origin: fifth, sixth, seventh costal cartilages.
• Insertion: Only Pubic CREST.
Origin and insertion of external oblique
• Origin: outer surface of lower eight ribs.
E8
• Insertion: linea alba, pubic crest, pubic tubercle, anterior half of iliac crest.
• Fibres run downwards and medially.(Pocket)
(into Iliac crest and Pubic crest)
Formation of inguinal ligament
• Between anterior superior and iliac spine and pubic tubercle, recurved lower border of external oblique forms the inguinal ligament.
Origin and insertion of internal oblique
• Origin: lumbar fascia, anterior two-thirds of iliac CREST and lateral two-thirds of inguinal ligament.(As Continuous strip)
• Insertion: linea alba and pubic CREST via conjoint tendon
(Iliac crest to Pubic crest)
Origin and insertion of transversus abdominis
• Origin: deep surface of lower sixth costal cartilages (interdigitating with diaphragm-THAT’S WHY LOWER 6) lumbar fascia, anterior two-thirds of iliac CREST, lateral THIRD of inguinal ligament.
• Insertion: linea alba and pubic CREST via the conjoint tendon.
(Iliac crest to Pubic crest)
What is line of Douglas with it’s importance
• The lower border of the POSTERIOR aponeurotic part of the Rectus sheath is marked by a crescentic line halfway between umbilicus and pubic symphysis
the Arcuate line of Douglas
IMPORTANCE
• At this point the inferior epigastric vessels enter the sheath.The epigastric vessels (superior and inferior) are applied to the POSTERIOR surface of the rectus muscle. Rupture of these with violent contraction of the rectus muscle leads to a rectus sheath HAEMATOMA.
• A SPIGELIAN hernia emerges at the LATERAL part of the rectus sheath at the level of the arcuate line of Douglas.
•Aponeurosis of internal oblique doesn’t split below this Arcuate line.
Formation and extension of Linea Alba
• The rectus sheath fuses in the midline to form the linea alba, which runs from the xiphisternum to the pubic SYMPHYSIS.
When both sided Kocher’s incisions are connected? And which nerve is at risk?
For anterior approach to kidneyS
9th coastal nerve, inquiry may lead to incisional hernia
Lanz Incision and Gridiron Incision
McBurney’s point is at two-thirds from the umbilicus to the anterior superior iliac spine.
Gridiron (muscle splitting) is VERTICAL on the joining line
The Lanz (Rockey-Davis) it’s a variation of the traditional Gridiron incision. So it is also made at McBurney’s point,The Lanz incision is more transverse than McBurney’s incision, it is HORIZONTAL to transverse plane, and it extends more medially toward the rectus abdominis
Which muscle is not encountered in grid iron incision
External oblique
(Cause here it has become aponeurotic)
Relation of vessels with tendinous intersections of rectus abdominis
segmental vessels enter here and bleeding will be encountered in case of paramedian incision
What is Battle incision with indication
William Henry Battle is known for a number of medical discoveries, including Battle’s incision, Battle’s Sign, and Battle’s operation. Battle’s Sign is a bruise over the mastoid process that indicates a basilar skull fracture. Battle’s operation is a surgical procedure for femoral hernia.
Pararectus incision (rectus muscle is retracted medially)
Indication
1.more often for open insertion of peritoneal dialysis catheters (Tenckhoff
catheter for continuous ambulatory peritoneal dialysis).
2.occasionally for appendicectomy
Deep Inguinal Ring
• DEFECT in transversalis fascia
• Lies 1 cm above midpoint of inguinal ligament.
• Immediately LATERAL to inferior epigastric vessels.
Superficial Inguinal Ring
• V-shaped DEFECT in inguinal LIGAMENT.
• Lies above and MEDlAL to pubic TUBERCLE
Spermatic Cord contains what?
• Three layers of fascia
• Three arteries
• Three nerves
• Three other structures
What is medial compartment of the femoral sheath?
FEMORAL CANAL
What forms the femoral sheath?
Femoral sheath is prolongation of transversalis fascia anteriorly and iliacus fascia posteriorly
Boundaries of the femoral ring
• anterior:ligament of Poupart
• posteriorly:ligament of Astley Cooper
• laterally: femoral vein(so it’s space for expansion is medically)
• medially:ligament of Gimbernat
inguinal ligament (of Poupart)
pectineal ligament (of Astley Cooper)
lacunar ligament (of Gimbernat)
CAUTION:
Occasionally an abnormal obturator artery runs in close relationship to the lacunar ligament and is in danger during surgery for femoral hernia.
What are the contents and function of femoral canal?
• fat
• lymphatics
• lymph node (Cloquet’s node).
#Cloquet’s node, also known as Rosenmüller’s node, is the topmost lymph node in the deep inguinal lymph node group.
(one of the ring’s functions is dead space for expansion of femoral vein, other function is pathway for lymphatics of lower limb to external iliac
nodes.)
Origin point of direct hernia
A direct hernia BULGES through the POSTERIOR wall of the inguinal
canal medial to the INFERIOR epigastric artery through Hesselbach’s triangle.
Boundaries of Hesselbach’s triangle
• laterally: inferior epigastric artery
• inferiorly: inguinal ligament
• medially: lateral border of rectus abdominis.
Distinction between direct and indirect inguinal hernia at operation depends on what?
depends on relationship of sac to the INFERIOR epigastric vessels:
direct hernia is medial,
indirect lies lateral to the artery.
Clinical distinction between inguinal and femoral hernias depends on what?
Depends on the relationship to the pubic TUBERCLE:
inguinal hernias lie above and medially, femoral hernias lie below and laterally.
Clinical distinction between inguinal and femoral hernias depends on what?
Depends on the relationship to the pubic TUBERCLE:
inguinal hernias lie above and medially, femoral hernias lie below and laterally.
Lining of peritoneum
Lined by mesothelium (simple squamous epithelium).
What is the pouch of Douglas?
It is rectouterine pouch
What is the Falciform ligament?
Falciform ligament passes upwards from umbilicus and slightly to right of midline to liver (containing the ligamentum teres in its free edge).
What is the lesser omentum?
After enclosing the liver the peritoneum descends from
the porta hepatis as a double layer, i.e. the lesser omentum.
What is the greater omentum?
Lesser omentum separates to enclose the stomach, reforming again on the greater curvature, and then LOOPS DOWNWARDS
again, TURNING UPWARDS (so 4 layers of two fold visceral peritoneum) and attaching to the length of the transverse colon, forming the greater omentum.
Describe transverse mesocolon’s position.
The transverse mesocolon is a fold of peritoneum originating from lower lip of greater omentum that surrounds the transverse colon and connects it to the posterior abdominal wall.
Examples of intraperitoneal organs
organs located within the visceral peritoneum of the abdominal cavity. The visceral peritoneum COVERS the organs on BOTH the FRONT and BACK surfaces.
EXAMPLES:
Right surface of abdominal oesophagus
Stomach
Liver
Spleen
Tail of pancreas (within linorenal ligament)
First and fourth parts of the duodenum
Jejunum
Ileum
Caecum
Transverse colon
Sigmoid colon
Upper third of rectum
Dome of bladder
Uterus
Location of he lesser sac
A space in the abdomen BETWEEN the STOMACH and PANCREAS. It’s part of the peritoneal cavity and is formed by the lesser and greater omentum(including space between descending and accenting lips).
The ONLY natural communication between the greater and lesser peritoneal sacs is the omental foramen, also known as the foramen of Winslow or the epiploic foramen.
The omental foramen is a small window with clear borders that define it:
Anterior: Hepatoduodenal ligament
Posterior: Inferior vena cava and the right crus of the diaphragm
Superior: Caudate lobe of the liver
Inferior: Superior part of the duodenum
The lesser sac, also known as the omental bursa, is located behind the stomach and lesser omentum, and in front of the pancreas and duodenum. Its function is to allow the stomach to move without restriction.
Which artery is pinched in Pringle’s manoeuvere?
Hepatic artery
Which is left subhepatic space
Lesser sac
Another name of the right subhepatic space with boundaries.
• Right subhepatic space (renal well of Rutherford Morrison) is bounded by:
• above: liver with attached gall bladder
• behind: posterior abdominal wall and kidney
• below: duodenum.
What separates right and left subphrenic spaces
Falciform ligament
What is Psoas test
An inflamed retrocaecal or retrocolic appendix lies in contact with psoas—the resulting spasm in the muscle leads to persistent flexion of the hip and pain on attempted extension.
Where does the abdominal aorta divide into the common iliac arteries?
left side of front of body at fourth lumbar vertebra
Level of bifurcation of common iliac artery
Sacroiliac joint
Origin of inferior epigastric artery
From external iliac artery just above inguinal ligament
Level of formation of IVC
Formed by junction of two common iliac veins behind the right common iliac artery at the level of the 5TH lumbar vertebra
Why should we take caution for aortic and hypogastric plexuses?
The pelvic plexus receives sympathetic and parasympathetic nerves, which provide deep autonomic innervation to the organs involved in ejaculation.This includes the prostate, seminal vesicles, and vas deferens. Norepinephrine is the neurotransmitter that stimulates the sympathetic nervous system, while acetylcholine is the parasympathetic neurotransmitter.
• Resection of abdominal aortic aneurysm and extensive pelvic dissection may remove aortic and hypogastric plexuses and hence compromise ejaculation.
Surgical treatment for planter hyperhidrosis or vasospastic conditions of the lower limb.
Lumbar sympathectomy.
Usually the second, third and fourth ganglia are excised with the intermediate chain.
Similarity between coccygeus muscle and sacrospinous ligament
Both of them have the same attachments
Nerve supply of levator Ani muscle
Perineal branch of S4 on pelvic surface, and
branch of the inferior rectal and perineal division of the pudendal nerve on the perineal surface.
Something about Pelvic fascia.
• Parietal pelvic fascia is a strong membrane covering the muscles of pelvic wall and is attached to bones at margins of muscles.
• Visceral pelvic fascia is loose and cellular over movable structures, e.g. levator ani, bladder, rectum.
• It is strong and membranous over fixed or nondistensible structures, e.g. prostate.
Parts of levator ani muscle
From before backwards
•A sling from pubis to perineal body (Levator prostate/sphincter vaginae)
•Forms a sling around the rectum and anus inserting into and reinforcing the deep part of the anal sphincter at the anorectal ring called Puborectalis
•Pubococcygeus
•Iliococcygeus
Division of cloaca,cloacal membrane and perineum by urorectal septum
•Cloaca >urogenital sinus+anorectal sinus
•Cloacal membrane >urogenital membrane +anorectal membrane
•Perineum>urogenital triangle+anal triangle
(Horizontal) (30°tilted)
How does genial TUBERCLE is formed?
By proliferation of mesoderm which elevates adjacent ectoderm turning into penis/clitoris.
So this TUBERCLE is part of phallic part of urogenital sinus
Fate of urachus TUBE
median umbilical LIGAMENT
Location of deep perineal pouch and contents
Deep to perineal membrane
Contents
Deep transverse perineal muscle
External urethral sphincter
Bulbourethral gland of Cowper (but it’s counterpart Bartholin’s gland of female is located in superficial perineal pouch)
Passage of urethral, vagina
The location of ischioanal fossae, contents and clinical importance
Clinical Points
Between levator ani superiorly and deep perineal pouch(deep to perineal membrane) inferiorly on each sides of anal canal
Or
Between pelvic diaphragm(levator ani is a part of it) and urogenital diaphragm(anterior part of perineal membrane)
*Contents:
•Mainly fat and is crossed by the inferior rectal vessels and nerves from lateral to medial side.
• The internal pudendal vessel and pudendal nerve lie on the lateral wall of the fossa in the pudendal canal (of Alcock), a TUNNEL of FASCIA which is continuous with the fascia overlying obturator internus.
• Infection of the ischiorectal space may occur from boils or abscesses on the perianal skin, from lesions within the rectum and anal canal, from pelvic collections bursting through levator ani.
• The fossae communicate with one another behind the anus, allowing infection to pass readily from one fossa to another.
• The pudendal nerves can be blocked in Alcock’s canal on either side, giving regional anaesthesia in forceps delivery.Pudendal nerve is seen arising from S2–S4 and exiting pelvis to enter gluteal region through the greater sciatic foramen. The nerve gives rise to the inferior rectal nerve, perineal nerve, and the dorsal nerve of the penis or clitoris.
Location of superficial perineal pouch, it’s important contents and another name
Between PERINEAL MEMBRANE and relevant part of COLLES’ FASCIA [deeper layer (membranous layer) of the superficial perineal fascia. It is thin, aponeurotic in structure, and of considerable strength]
•Bulbospongiosus muscle covers the bulb of the penis and the corpus spongiosum.
•Ischiocavernosus muscle covers the crus of the penis and the corpus cavernosum.
•Superficial transverse perineal muscle
•Erectile tissues(spongiosum,cavernosum)
•Bartholin’s gland(of female)
Colles ligament (1811) – small triangular fascia that springs from the pubic crest and ilio-pectineal line and passes upwards and inwards towards the linea alba under cover of the internal pillar of the external abdominal ring. It is also called the reflected inguinal ligament (triangular fascia) is a layer of tendinous fibers of a triangular shape, formed by an expansion from the lacunar ligament and the inferior crus of the subcutaneous inguinal ring.It passes medialward behind the spermatic cord, and expands into a somewhat fan-shaped band, lying behind the superior crus of the subcutaneous inguinal ring, and in front of the inguinal aponeurotic falx, and interlaces with the ligament of the other side of the linea alba.
Superficial and Deep transverse perineal muscle
•Superficial runs across the superficial perineal space.The deep branch of the perineal nerve innervates this muscle.
•Deep is located in the deep perineal space.The pudendal nerve innervates this muscle.
Which ligament gives origin to gluteus maximus?
Sacrotuberous
Relation between BULB of penis and GLANS of penis
Corpus SPONGIOSUM Commences at the perineal membrane by an enlargement the BULB and Runs forward in the groove on the undersurface of the corpora cavernosa, expanding over their extremities to form the GLANS.
Relation between BULB of penis and GLANS of penis and function of their connection
Corpus SPONGIOSUM Commences at the perineal membrane by an enlargement the BULB and Runs forward in the groove on the undersurface of the corpora cavernosa, expanding over their extremities to form the GLANS.
*Function
The function of the corpus spongiosum in erection is to prevent the urethra from pinching closed, thereby maintaining the urethra as a viable channel for ejaculation. To do this, the corpus spongiosum remains pliable(flexible) during erection while the corpora cavernosa penis become engorged with blood.
Demarcating line between membranous and spinach urethra
The perineal membrane is an anatomical term for a fibrous membrane in the perineum. It is the superior border of the superficial perineal pouch, and the inferior border of the deep perineal pouch. The perineal membrane is triangular in shape. It attaches to both ischiopubic rami of the pelvis.
Location of external urethral sphincter
The membranous urethra is surrounded by the external urethral sphincter, which is made up of an internal lissosphincter(smooth muscle) and an external rhabdosphincter(striated muscle).
Location of external urethral sphincter
The membranous urethra is surrounded by the external urethral sphincter, which is made up of an internal lissosphincter(smooth muscle) and an external rhabdosphincter(striated muscle).
What forms prepuce in female
Labia minora
Why do we use a scrotal suspension bag after hernial surgery?
Scrotal subcutaneous tissue is continuous with the fascia of the abdominal wall and perineum; extravasation of urine or blood deep to this plane gravitates into the scrotum, hence frequent bruising of scrotum following hernia repair..Also it fills with oedema fluid in cardiac or renal failure.
Function of the seminiferous tubules.
Sperm is produced here
Testicular artery anastomoses with which artery? And importance of anastomosis.
• Testicular artery anastomoses with artery to vas (which supplies the vas deferens and epididymis), which arises from the inferior vesical branch of the internal iliac artery.
• Anastomosis between these two arteries means that ligation of the testicular artery is not necessarily followed by testicular atrophy.
Level of formation of testicular vein
•Pampiniform plexus becomes a single vessel, the testicular vein, at the DEEP
inguinal ring.
• Right testicular vein drains into the IVC; the left into the
left renal vein.
Testis arises at which level ?
The testis arises at the level of L2/3 on the posterior abdominal wall.
The common ejaculatory duct opening
• The common ejaculatory duct traverses the prostate to open into the prostatic urethra at the Verumontanum on either side of the Utricle.
Relation of oesophagus and crus of diaphragm
It passes through oesophageal opening in the Right crus of the diaphragm at level T10.
Blood Supply of oesophagus in neck, thorax and abdomen.
•Arterial supply:
• In the neck from the inferior thyroid arteries.
• In the thorax: from branches of the aorta.
• In the abdomen: from the left gastric and inferior phrenic arteries.
:• Venous drainage:
• cervical part to inferior thyroid veins
• thoracic part to azygos veins
• abdominal part to azygos vein (systemic) and partly to the left gastric veins (portal).
Nerve Supply of oesophagus
The PNS stimulates peristalsis through the myenteric plexus. It also decreases the pressure in the LES.PNS increases secretory activity.
• Upper third: parasympathetics via recurrent laryngeal nerve and sympathetic nerves from the middle cervical ganglion along the inferior thyroid artery.
• Below the root of the lung, the
vagi (parasympathetic) and sympathetic nerves contribute to the oesophageal plexus.
#The SNS is part of the thoracic and cervical chain nerves.
SNS can constrict blood vessels in the esophagus,relax the muscle wall of the esophagus ,cause contractions of the upper and lower esophageal sphincters (UES and LES).The SNS can sense pain directly.
Why there is a risk of dysphagia in thyroid surgery
May occur from injury to recurrent laryngeal nerve supplying upper third of oesophagus
Muscle of esophagus
Upper third is striated
Lower 2/3 is smooth
Type of inner and outer lining of esophagus
Inner by stratified squamous
Outer by loose areolar
Level of 3 esophageal constrictions
17 cricoid/commencement
28 left main bronchus
43 diaphragm/termination
In the lower oesophagus there is a site of portosystemic anastomosis by which vessels?
between the azygos vein (systemic)
and the oesophageal tributary of the left gastric vein(portal).
Oesophageal varices may arise at this site in portal hypertension.
Relation of mitral stenosis and esophagus
•Left atrial enlargement owing to mitral stenosis may be noted on a barium swallow, which shows marked BACKWARDS displacement of the oesophagus by the dilated atrium.
What is incisura angularis?
• Junction of body with pyloric antrum marked along the lesser curve by a notch—the incisura angularis.
Importance of prepyloric vein of Mayo
•The prepyloric vein is the final branch that connects to the right gastric vein, which drains the duodenum’s proximal part
•. Junction of pylorus with duodenum is MARKED by a constant prepyloric vein of Mayo, which crosses it vertically.
•The prepyloric vein of Mayo MARKS the distal end of a pyloric tumor.
•During surgery, surgeons stop the myotomy 1–2 mm short of the prepyloric vein to prevent duodenal perforation.
Where does the stomach drain it’s blood
Into portal system
•Left and right gastric veins: Drain into the portal vein
•Short gastric veins and left gastroomental(gastroepiploic) vein: Drain into the splenic vein
•Right gastroomental vein: Drains into the superior mesenteric vein
Ultimate destination of lymph from stomach
Coeliac nodes
Which vagus supplies pyloric sphincter?
Pyloric branch of anterior vagus ( because it is in close proximity to the stomach)
nerves of Latarjet
Gastric divisions of both anterior and posterior vagi descend from cardia along the lesser curve between the anterior and posterior peritoneal attachments of the lesser omentum.These nerves are referred to as the anterior and posterior nerves of Latarjet.
Division of gastric mucosa with function
cardiac gland area -mucus
oxyntic (parietal) gland area with chief-acid, zymogen
pyloric end area -gastrin,mucus
Relation among the second part of the duodenum,transverse colon,right kidney
and ureter.
The second part of the duodenum is crossed by the transverse colon and lies anteriorly to the right kidney and ureter.
Relation among third Part of duodenum, the IVC, the aorta and third lumbar vertebra,root of the mesentery and superior mesenteric vessels.
•Third Part of duodenum crosses the IVC, the aorta and third lumbar vertebra.
• Crossed anteriorly by the root of the mesentery and superior mesenteric vessels.
What is the suspensory ligament of Treitz(ˈtrīts)? And it’s importance.
It is a peritoneal fold descending from the RIGHT crus of the diaphragm (not left) to the termination of the duodenum at the DJ flexure.
The ligament of Treitz can range in length from half an inch to 2.5 inches. It’s made up of skeletal muscle from the diaphragm and smooth muscle from the duodenum.
*Importance
•At surgery the DJ flexure may be identified by the presence of the ligament
•An abnormally long ligament can cause intestinal malrotation.
•Abnormal thickening, hypertrophy/some primary and metastatic tumors can involve the ligament, or shortening of the ligament can RARELY lead to SMAS (Superior mesenteric artery syndrome).Contraction of the ligament pulls the duodenum upward into the vascular angle between the superior mesenteric artery and the aorta.
Importance of posterior relation of gastroduodenal artery to 1st part of duodenum
Erosion
of POSTERIOR duodenal ulcers into the gastroduodenal
artery will cause haematemesis AND melaena.
mesentery vs omentum
A large double layer called the omentum covers the front of your abdomen like an apron. A double layer in the back called the mesentery attaches your intestines to your back abdominal wall.
What is the marginal artery of Drummond?
The marginal artery of Drummond, also known as the marginal arcade, is an anastomotic arterial channel that supplies the entirety of the large intestine. It extends from the ileocecal junction to the rectosigmoid junction. As it runs in close proximity along the inner border of the large intestine, it is sometimes referred to as juxtacolic artery.
Attachment of root of the mesentery of the small intestine
• Commences at DJ flexure to the LEFT (so it is on right side of the midline)of the SECOND lumbar vertebra and passes obliquely downwards to the RIGHT sacroiliac joint.
Nerve in mesentery of small intestine
Autonomic nerve
What is valvulae conniventes/Kerckring folds/plicae circulares?
circular folds of mucosa of the jejunum
Attachment of root of transverse mesocolon
The root of the transverse mesocolon attaches to the inferior border of the pancreas, along its long axis and tail.
Ligamental attachment of hepatic flexure and splenic flexure
•The hepatocolic ligament is a fold of peritoneum that connects the hepatic flexure to the liver’s lower surface near the gallbladder.
•The phrenicocolic ligament is a fold of
peritoneum. It forms part of the greater omentum. It attaches the transverse colon, at the splenic flexure, to the left side of the diaphragm near the eleventh rib. This ligament is located inferior and lateral to the spleen.
Attachment of sigmoid mesocolon
Inverted V with the base attached to the retroperitoneum in the left lateral pelvis from point of division off left common iliac artery along external and internal iliac artery (upto S3) in posterior abdominal wall.Although anatomists point to the level of the third sacral vertebrae as the beginning of the rectum, surgeons advocate the sacral promontory as its origin.
Narrowest part of colon
The sigmoid colon is the narrowest portion of the colon, with a diameter equivalent to that of the ileum.
Course of the mesorectum
The mesorectum begins at the sacral promontory and ends approximately 2 cm superior to the pelvic diaphragm.
Rectal lateral inflexions
Three lateral inflexions projected to the LEFT, RIGHT and LEFT again from above downwards.(Like marching)
Counterpart of denovillers fascia
Pouch of Douglas
Area of supply of inferior rectal artery
Inferior half of anal canal
Area of supply of middle rectal artery
Muscle coat of rectum
Area of supply of superior rectal artery
Whole rectum and superior half of anal canal
Classical position of haemorrhoid and reason behind
Haemorrhoids occur at 3, 7 and 11 o’clock.
The position of beaches of superior rectal artery and vein, one on the left and two on the right
Importance of marginal artery of Drummond
• The marginal artery is weakest and sometimes deficient where the superior and inferior mesenteric artery distributions meet just proximal to the splenic flexure.(Location of marginal artery is here) Diminution of the blood supply in this region may lead to the condition known as ischaemic colitis.
• The marginal artery is also important in allowing the surgeon to transpose large segments of colon as far as the neck or thorax to replace segments of oesophagus, the bowel depending on the marginal artery for its blood supply.
Ultimate destination of lymph from large intestine
Cisterna chyli
Location of columns of Morgagni
At the midpoint of the anal canal there is a series of vertical columns in the mucosa
Location of valves of Ball
• At the distal end of the vertical columns of Morgagni are some valve-like folds (the anal valves of Ball).
• Behind these valves are the anal sinuses into which open the anal glands.
Differ upper half and lower half of anal canal
endoderm-ectoderm
columnar-stratified squamous
adenocarcinoma-squamous cell carcinoma
autonomic-inferior rectal nerve
insensitive -sensitive(important factor when injecting haemorrhoids)
portal-systemic
abdominal-inguinal
parts of external anal sphincter
The external anal sphincter is divided into three parts:
• subcutaneous, the subcutaneous part of the external anal sphincter is traversed by a fan-shaped expansion of longitudinal muscle fibres of the anal canal.
• superficial, which is attached to the coccyx behind and the perineal body in front
• deep, which is continuous with the puborectalis part of levator ani.
What is anorectal ring?
The deep part of the external sphincter where it blends with levator ani together with the internal anal sphincter is termed the anorectal ring. Ring is palpable with a finger in the anal canal where it forms a ring, immediately above which the finger enters the ampulla of therectum.
The nerve supply of the external sphincte
They have different functions
Via the inferior rectal (S2-3) branch of the pudendal nerve and the perineal (S4) branch of pudendal nerve (S2-4)
•Inferior rectal nerve
Controls the external anal sphincter and provides sensory information to the anal canal and perianal skin. The inferior rectal nerve also provides sensation to the lower anal canal, which makes it sensitive to pain, touch, and temperature. Damage to the inferior rectal nerve can lead to fecal incontinence.
•Perineal nerve
Controls the pelvic floor muscles and the urethral sphincter. The perineal nerve also innervates the bulbospongiosus muscle, the ischiocavernosus muscle, the superficial transverse perineal muscle, and the labial skin.
Function of the coronary ligament,
The posterior surface over the right lobe of the liver is connected to the diaphragm by the coronary ligament,between the two layers of which is a non-peritonealized
area, i.e. the bare area
Hepatic attachment of lesser sac and important hepatic ligaments.
The lesser sac is attached to the liver by the hepatoduodenal ligament and the hepatogastric ligament, which are both part of the LESSER omentum (that’s why there ligaments are two folded).It runs from the porta hepatis and ligamentum venosum fissure to the stomach’s lesser curvature.
*Hepatoduodenal ligament
Connects the liver (around porta hepatis) to the first part of the duodenum. It surrounds the portal triad.
*Hepatogastric ligament
Connects the liver (fissure for ligamentum venosum) to the lesser curvature of the stomach. It contains the left and right gastric arteries, and separates the greater and lesser sacs on the right side of the abdominal cavity.
*The ligamentum VENOSUM, also known as ARANTIUS’ ligament, is the fibrous remnant of the ductus VENOSUS of the fetal circulation. Usually, it is attached to the LEFT branch of the portal vein WITHIN the porta hepatis. It may be continuous with the ROUND ligament of the liver.
*During normal development, the right umbilical vein slowly becomes atretic at the embryonic fourth week and completely disappears by the seventh week. There is degeneration of the segment of the left umbilical vein between the liver and the sinus venosus called ligamentum TERES/ROUND ligament of liver (venous remnant). It is received by the liver within the FALCIFORM ligament (peritoneal fold).
Formation of triangular ligaments of liver
Upper and lower leaves of coronary ligament fuse to form the right and left triangular ligament.
(Both attach to the diaphragm)
Which omentum contains porta hepatis
The free (right) edge of the lesser omentum in the anterior wall of the foramen of Winslow contains the porta hepatis with common bile duct to the right, the hepatic artery to the left and the portal vein posteriorly.
Their relations are as follows:
• bile duct: anteriorly to the right
• hepatic artery: anteriorly to the left
• portal vein: posterior
IVC lies posteriorly: separated from the portal vein by the epiploic foramen.
Mnemonic for why CAUDATE lobe is no 1
It has its own independent caudate artery, independent hepatic veins and it also receives blood from both the left and right portal veins.
Segments involve in hemihepatectomy and lobe excision
• A right hemihepatectomy would involve segments V, VI, VII and VIII.
• A left hemihepatectomy would involve segments II, III and IV
• Excision of the anatomical left lobe of the liver would involve only segments II and III.
• Excision of the functional left lobe of the liver would involve segments II, III, IV and possibly I.
What is the valve of Heister?
• The lumen of the cystic duct contains a spiral mucosal valve (of Heister).
Hartmann’s pouch with it’s importance
• A small pouch may be present on the ventral aspect of the gall bladder just proximal to the neck (Hartmann’s pouch); a stone may lodge in the pouch.
Calot’s triangle with it’s importance.
A triangle made up of the liver, the
cystic duct and the common hepatic duct. Cystic artery lies in a triangle. But gall bladder also receives blood from the hepatic bed and drains into hepatic bed.
Relation between cholecystoduodenal fistula and gallstone ileus.
Courvoisier first described gallstone ileus as a late complication of cholecystitis in 1890.
•A cholecystoduodenal fistula usually caused by a gallstone penetrating the wall of a chronically inflamed gallbladder that’s adhered to the duodenum can lead to subsequent gallstone ileus, a rare and life-threatening condition that occurs when a gallstone passes through a fistula into the small intestine, causing a mechanical obstruction.Gallstones that are usually 2 to 2.5 centimeters in size are typically the cause of gallstone ileus,usually in the ileum, which is the narrowest part of the intestine.
#The classic radiologic sign of gallstone ileus is the Rigler triad (also called Rigler sign): pneumobilia, intestinal obstruction and an ectopic gallstone.
Basic of Courvoisier’s law
CHRONIC nature of the obstruction GRADUALLY distends the gallbladder over time, WITHOUT causing acute damage, thus WITHOUT causing pain.
Basic of portal system and area of drainage
A portal system is one that has capillaries at each end.
Drains🩸 from
• the abdominal part of the alimentary canal (EXCLUDING the lower part of the anus)
• spleen
• pancreas
• gall bladder.
Sites of anastomosis between portal and systemic venous system
S-superior
I-inferior
A-anterior
P-posterior
SR-superior right
•S: between the oesophageal branch of the left gastric vein (portal) and the oesophageal tributaries of the azygos system (systemic); in the presence of portal hypertension oesophageal varices will develop that may be the source of severe haematemesis
•I: between the superior rectal branch of the inferior mesenteric vein (portal) and the inferior rectal veins (systemic); this may give rise to dilated veins in the anal canal which bleed
•P: between the portal tributaries in the mesentery and retroperitoneal veins (systemic), resulting in retroperitoneal varices
•A: between the portal veins in the liver and the veins of the abdominal wall (systemic) via veins passing along the falciform ligament to the umbilicus; this may result in the formation of a group of dilated veins radiating out from the umbilicus known as a caput medusae
•SR: between portal branches in the liver and the veins of the diaphragm (systemic) in relation to the bare area of the liver.
uncinate process and superior mesenteric vessels
The uncinate process lies behind the superior mesenteric vessels.
Relation of The stomach and first part of the duodenum with head of the pancreas
• The stomach and first part of the duodenum lie partly in front of the head of the pancreas, separated from it by the lesser sac.
Some points of structure of pancreas
*encapsulated by fibrous capsule
* capsule sending septae into the gland, forming lobules
*Lobules composed of acini of serous cells
*serous cells secrete pancreatic ENZYMES
*Ducts lined by cuboidal epithelium
*cuboidal epithelium drain secretions
into pancreatic ducts
*spheroidal clusters of pale-staining cells with a rich blood supply are the islets of
Langerhans
*Iislets of Langerhans are scattered throughout the pancreas
*Cells of islets of Langerhans secrete insulin (beta) AND glucagon (alpha)
What forms the left lateral extremity of LESSER sac
Spleen
How do gastrosplenic ligament and lienorenal ligament connect spleen
*gastrosplenic ligament connects it to the greater curvature of the stomach
*lienorenal ligament connects it to the posterior abdominal wall .
The splenic artery and vein, lymph nodes and the tail of the pancreas are enclosed in the lienorenal ligament.
Capsules of kidney
Anterior - Gerota
Posterior - Zuckerkandl
fascia >2 is separated from kidney by perinephric fat >1
True fibrous capsule >3
123 from out to inwards
Relations of ureter in pelvis
Relations in the pelvis:
• In the male:
• each ureter enters the pelvis by crossing the BIFURCATION of the common iliac artery; runs down to ischial SPINE, crossing the obturator nerve and the ANTERIOR branches of the internal iliac artery; turns medial to reach the bladder and passes BELOW the vas deferens just before entering the bladder.
• In the female:
• course as above for male, but ureter crosses close to the lateral FORNIX of the vagina BELOW the uterine artery and posterior part of bladder, and ends as in male.
Narrowest parts of ureter
• Narrowest parts of ureter are:
• pelviureteric junction
• at the brim of the pelvis
• at entry to bladder.
• Calculus may impact at one of these three areas.
Blood supply of the ureter
SEGMENTAL
• renal arteries (may receive a considerable contribution from a lower polar artery)
• testicular or ovarian artery (gonadal)
• internal iliac artery
• inferior vesical arteries
Movement of ureter
worm-like movements can be noticed in its wall, particularly if it is stimulated by the tip of a pair of forceps.
How to observe for a ureteric stone on a plain radiograph
Along the course of the ureter projected onto the bony
skeleton:
• runs ALONG the tips of the transverse processes
• crosses in FRONT of the sacroiliac joint
• swings OUT on the pelvic wall and crosses the ischial spine
• passes MEDIALLY to bladder.
Difference between adrenal glands
•They are asymmetrical.
• Right is pyramidal and embraces the upper pole of the right kidney.
• Left is crescentic and embraces the medial border of the left kidney above the hilum.
Blood Supply of adrenal gland
• A branch from the aorta.
• A branch from the inferior phrenic artery.
• A branch from the renal artery.
• Venous drainage on the right is via a short vein directly into the IVC.
• Venous drainage on the left is by a longer vein into the left renal vein.
Difference between cortex and medulla of adrenal gland
• Medulla derived from neural crest (ectoderm).
• Cortex derived from mesoderm.
• Medulla receives preganglionic sympathetic fibres from the greater splanchnic nerve and secretes adrenaline and noradrenaline.
• The cortex secretes mineralocorticoids (from zona glomerulosa), glucocorticoids (from zona fasciculata) and sex hormones (from the zona reticularis).
*G
The name comes from the Latin word glomerulus, which means “cluster or knot”.
*F
Columnar epithelial cells that are arranged in bundles, or “fascicles”.
*R
Having the form of a net.Made up of irregularly arranged cylindrical masses of epithelial cells.
Lymphatic Drainage of urinary bladder
• Drainage along the vesical vessels to the internal iliac nodes and then to the para-aortic nodes.
Nerve Supply of urinary bladder
*parasympathetic(S2, S3, S4)>motor to muscles & inhibitory to INTERNAL sphincter.
*Sympathetic>motor to its sphincter & inhibitory fibres to bladder muscles
• Sensory fibres, stimulated by distension, are conveyed in both sympathetic and parasympathetic nerves.
What is cave of Retzius
The retropubic space.It is extraperitoneal.
Location of prostatic venous plexus
prostatic venous plexus lies between the true and false capsules
Importance of veins of Batson
Some venous blood drains posteriorly around the rectum to the valveless vertebral veins of Batson—this may explain why prostatic carcinoma metastasizes early to the bones of the lumbar spine and pelvis.
Origin and branches of uterine artery
•From the internal iliac artery.
•Ascending(uterus, fallopian tube) and descending(cervix, upper vagina) branches from the level of internal OS.
Lymphatic drainage of uterus
Fundus-para aortic , inguinal
Body-internal iliac
Cervix-laterally external iliac
-posteriolaterally internal iliac
-posteriorly sacral
Parts of fallopian tube
*infundibulum:trumpet,opens into the peritoneal cavity at the ostium
*ampulla:wide,tortuous and thin-walled
*isthmus:narrow, straight and thick-walled
*intramural
Blood supply of vagina
*The arterial blood supply is derived from several sources on each side:
• the vaginal artery
• the uterine artery
• the middle rectal artery
• the internal pudendal artery supplying the lower third.
* Venous drainage is via a plexus of veins in the connective tissue around the vagina draining into the internal iliac vein.
Lymphatic drainage of vagina
• From the upper and middle third drain into the external iliac nodes.
• From the lower third drains into the superficial inguinal nodes.
Suspension of ovary
• The superior pole is attached to a prominent fold of peritoneum, the suspensory ligament of the ovary, which passes upwards over the pelvic brim and external iliac vessels to merge with the peritoneum over psoas MAJOR.
• Ovarian artery gains access to the ovary through the mesovarium and suspensory ligament.
Position of ovary
Variable
• Lies on the side wall of the pelvis in a shallow ovarian fossa(Fascia over obturator internus forms the floor of this
fossa) surrounded by the EXTERNALAL iliac vessels in FRONT and the ureter and INTERNAL iliac vessels BEHIND.
What is the first step in the development of the gut?
Formation of the foregut, midgut, and hindgut
Which germ layer gives rise to the epithelium of the gut?
Endoderm
What is the process by which the gut tube is formed called?
Gastrulation
True or False: The gut tube is initially a straight structure.
True
What is the role of the notochord in gut development?
Induces the formation of the gut tube
Which structure divides the foregut from the midgut?
Liver bud
What does the midgut give rise to?
Small intestine and part of the large intestine
What structure separates the foregut from the hindgut?
Duodenum
What is the function of the cloaca during gut development?
Receives the hindgut and urogenital sinus
Which germ layer gives rise to the muscular layers of the gut?
Mesoderm
What is the process by which the gut tube elongates called?
Caudal growth
What is the final step in gut development?
Formation of the anus
Which structure gives rise to the epithelium of the gut tube?
Endoderm
What does the hindgut give rise to?
Part of the large intestine, rectum, and anus
What is the role of the septum transversum in gut development?
Forms the diaphragm and separates the thoracic and abdominal cavities
What is the name of the condition where the gut tube fails to close properly?
Omphalocele
What is the function of the allantois in gut development?
Contributes to the formation of the urinary bladder
What is the name of the structure that connects the yolk sac to the midgut?
Vitelline duct
What is the process by which the gut tube rotates called?
Midgut rotation
What is the role of the neural crest cells in gut development?
Contribute to the enteric nervous system
What is the name of the condition where the gut tube twists abnormally?
Malrotation
What is the function of the notochord in gut development?
Induces the formation of the gut tube
Which structure gives rise to the muscular layers of the gut tube?
Mesoderm
What does the cloaca eventually differentiate into?
Urogenital sinus and anorectal canal
What is the name of the structure that connects the hindgut to the cloaca?
Cloacal membrane
What is the first step in the development of the gut?
Formation of the foregut, midgut, and hindgut
Which germ layer gives rise to the epithelium of the gut?
Endoderm
What is the process by which the gut tube is formed called?
Gastrulation
True or False: The gut tube is initially a straight structure.
True
What is the role of the notochord in gut development?
Induces the formation of the gut tube
Which structure divides the foregut from the midgut?
Liver bud
What does the midgut give rise to?
Small intestine and part of the large intestine
What structure separates the foregut from the hindgut?
Duodenum
What is the function of the cloaca during gut development?
Receives the hindgut and urogenital sinus
Which germ layer gives rise to the muscular layers of the gut?
Mesoderm
What is the process by which the gut tube elongates called?
Caudal growth
What is the final step in gut development?
Formation of the anus
Which structure gives rise to the epithelium of the gut tube?
Endoderm
What does the hindgut give rise to?
Part of the large intestine, rectum, and anus
What is the role of the septum transversum in gut development?
Forms the diaphragm and separates the thoracic and abdominal cavities
What is the name of the condition where the gut tube fails to close properly?
Omphalocele
What is the function of the allantois in gut development?
Contributes to the formation of the urinary bladder
What is the name of the structure that connects the yolk sac to the midgut?
Vitelline duct
What is the process by which the gut tube rotates called?
Midgut rotation
What is the role of the neural crest cells in gut development?
Contribute to the enteric nervous system
What is the name of the condition where the gut tube twists abnormally?
Malrotation
What is the function of the notochord in gut development?
Induces the formation of the gut tube
Which structure gives rise to the muscular layers of the gut tube?
Mesoderm
What does the cloaca eventually differentiate into?
Urogenital sinus and anorectal canal
What is the name of the structure that connects the hindgut to the cloaca?
Cloacal membrane
Abdominal muscles involved in grid iron incision
All of them except external oblique muscle but its aponeurosis is encountered
Components of posterior rectus sheath
Only fascia transversalis
Another name for left subhepatic space
Lesser sac
Relation between iliopsoas muscles
Reverse direction
Relation of epididimis and tunica vaginalis
The epididymis is covered by the tunica vaginalis except at its posterior margin which is free.
Origin of artery to the vas
inferior vesical branch of the internal iliac
artery.
Relation of aortic arch with esophagus
Aortic arch lies on left lateral side of oesophagus, compressing it
Relation of azygos vein with the esophagus
Azygos vein lies on right lateral side of thoracic esophagus
Duodenal relation with kidney
2nd part of duodenum lies anterior to right kidney and ureter
Crossing of 3rd of vertebra
—
L3
—
What gives suspension of DJ flexure
Right crus of diaphragm by Treitz ligament which a peritoneal fold
Which artery may be eroded by posterior duodenal ulcer
Gastroduodenal
Support of jejunum and ileum
Jejunum and ileum lie in free edge of mesentery.
Connection of mesentry of small intestine
Ligament of Treitz from Right crus of diaphragm at L2 level on left side superiorly
And
Right sacroiliac joint inferiorly
Blood supply of mesentry of small intestine
Superior mesenteric artery
Differ mesentery of jejunum and ileum
Lower mesentry becomes thicker and more fat laden (maybe because of gravity)
So that’s why upper straight arteries are longer having less arches
Extension of colon
Cecum to anus
Posterior attachment of transverse mesocolon
Anterior border of pancreas
Attachment of splenic flexure
To diaphragm
Extension of sigmoid colon
Commences at pelvic brim and extends to rectosigmoid junction.
Identifying point of cecum
Devoid of appendices apiploicae
Position of appendix
• 75% lies behind the caecum or colon, i.e. retrocaecal or retrocolic
• 20% pelvic
• 5% preileal or retroileal.
Position of appendix
• 75% lies behind the caecum or colon, i.e. retrocaecal or retrocolic
• 20% pelvic
• 5% preileal or retroileal.
Why obstruction of the appendicular lumen isuncommon at the extremes of life.
The lumen of the appendix is relatively wide in infancy and often obliterated in the elderly
How does appendicitis cause frequency of micturition
A long pelvic appendix may hang down and irritate the bladder, giving rise to frequency of micturition, simulating cystitis.
Extension of rectum
commencing anterior to the third segment of the sacrum and ending about 2.5 cm in front of the coccyx
Location of valve of Houston
Left —Right—Left
Rectal inflexion
Location of marginal artery of Drummond
Gut
Extension of superior rectal artery
Upto anal valve
Which vessel is related to haemorrhoids
Superior rectal artery
3 7 11 o’clock
Most common site for ischaemic colitis.
The marginal artery is weakest and sometimes deficient where the superior and inferior mesenteric artery distributions meet just proximal to the splenic flexure.
Diminution of the blood supply in this region may lead to the condition known as ischaemic colitis.
Example of—
High ligation of the vessels to the involved segment of bowel with the removal of a wide surrounding segment of mesocolon and bowel wall will result in the removal of lymph nodes draining that particular area
division of the inferior mesenteric artery and resection of
sigmoid mesocolon would be performed for carcinoma of the sigmoid colon.
Attachment of superficial part of external anal sphincter
coccyx behind and the perineal body in front
Attachment of deepl part of external anal sphincte
continuous with the puborectalis part
of levator ani.
Continuation of internal anal sphincter
composed of smooth muscle continuous above with the circular muscle of the rectum
Area coverage of internal anal sphincter
It surrounds the upper two-thirds of the canal
Nerve supply of internal anal sphincter
Sympathetic
Nerve supply of external anal sphincter
inferior rectal branch and the pudendal nerve (S2, S3)
and the perineal branch of S4.
Difference in wall of cystic duct and bile duct
Cystic has smooth muscle so lodgement if stone is painful
*Bimanual PVE assessment
Bimanual examination assesses pelvic size, size of uterus, position of uterus, enlargement of ovary, abnormalities of uterine tube.
*Pathology in pouch of Douglas in PVE
.
ovarian lesions, malignant deposits
*Structures related to ovarian fossa
OVARY surrounded by the EXTERNAL iliac vessels in front and the URETER and INTERNAL iliac vessels behind.OBTURATOR nerve is close by
*Location of ovarian fossa
Fascia over obturator internus forms the floor of this fossa
*Connection of ovarian ligament
runs within the broad ligament to the cornu of uterus.
*Support of ovarian artery
Ovarian artery gains access to the ovary through the mesovarium and suspensory ligament.
*Attachment of the suspensory ligament of the ovary
merge with the peritoneum over psoas major
*Lymphatic drainage of vagina
Upper and middle third external iliac
Lower third superficial inguinal
*Vaginal vein
internal iliac
*Supplying area of middle rectal artery other than rectum
Vagina
*Blood supply is vagina
vaginal
uterine
middle rectal
internal pudendal
*Lateral relation of lateral FORNIX of vagina
Ureter
*What separates anal canal from vagina
PERINEAL body
*Pouch behind posterior vaginal fornix
Pouch of Douglas (rectouterine)
*Lymphatic drainage of fundus of uterus
Para aortic
*Lymphatic drainage of cervix
External iliac
Internal iliac
Sacral
*Location is seminal vesicles
Lie one on each side in the interval between the base of the bladder anteriorly and the rectum posteriorly.
*Location and importance of veins of Batson
Some venous blood of prostate drains posteriorly around the rectum to the valveless vertebral veins of Batson—this may explain why prostatic carcinoma metastasizes early to the bones of the lumbar spine and pelvis.
*Surgical plane for benign prosthetic hyperplasia
Sub false capsule
*Location of Venus plexus of prostate
Outside the true capsule
*Fascia between prostate and rectum
Denovillers
*Sensory fibers of bladder
Sensory fibres, stimulated by distension, are conveyed in both sympathetic and parasympathetic nerves.
*Relation of vesicular nerve and artery
Efferent fibres from S2, S3, S4 accompany the vesical arteries
*Nerve for micturition—
parasympathetic
*Why relationship between the sigmoid colon and bladder is important?
Superiorly sigmoid colon is resting on it
and in diverticular disease when a colovesical fistula may arise.
*Adrenal GFR
G mineralocorticoid
F glucocorticoid
R sex hormone
*Development of adrenal gland
Medulla derived from neural crest (ectoderm).
• Cortex derived from mesoderm
*Blood supply of suprarenal glands
inferior phrenic,aorta,renal
*Difference between suprarenal glands
Right is pyramidal embracing upper pole
Left is crescentic embracing medial border
*ureteric stone on a plain radiograph may be seen along:
runs along the tips of the transverse processes—crosses in front of the sacroiliac joint—swings out on the pelvic wall and crosses the ischial spine—passes medially to bladder.
*ureter receives a rich segmental blood supply from
renal, gonadal,internal iliac ,inferior vesical
*Relations of ureter before termination:
In the male: below vas
In the female: below uterine artery
*Anatomy of surgical exposure of the kidney
an oblique incision is made halfway between the 12th rib and iliac crest, extending forwards from the lateral border of erector spinae to the lateral border of rectus abdominis
being careful not to damage the pleura
which descends below the medial half of the rib.
*Connection of renal fascia
(Zuckerkandl+Gerota)
Above,blends with the fascia over
the diaphragm
Medially, the blends with the sheaths of the aorta and IVC
Laterally, continuous with transversalis fascia.
It remains OPEN inferiorly.
*Content of the lienorenal ligament.
The splenic artery and vein, lymph nodes and the tail of the pancreas are enclosed in the lienorenal ligament.
*Relation of spleen and kidney
Medially: the left kidney.
*Sites of anastomosis between portal and systemic venous system are:
oesophageal
rectal
retroperitoneal
caput medusae
bare area
*Mechanism of formation of mucocele of gall bladder
When the NECK of the gall bladder is OBSTRUCTED, bile is absorbed and the goblet cells produce mucus, resulting in a mucocele of the gall bladder.
