ABDOMEN

Foregut: from mouth to duodenum (at entrance of bileduct)Midgut: 2/3 across transverse colonHindgut: to end

Regions

Vertical lines: midclavicular to midinguinalTransverse lines: subcostal plane (inf border of 10th costal cartilage); transtubercular plane (iliac tubercles @ level of L5)Anterolateral abdo wall bounded by cartilages of 7-10th ribs and xiphoid process, inguinal ligament and pelvic girdle (iliac crests, pubic crests, pubic symphysis)

Ant Abdominal WallFascia:

1) Camper fascia (superficial, fatty)2) Scarpa fascia (deep, membranous) –

extends to perineum to be Colles fascia, and to thigh as fascia lata

3) Investing fascia – cover muscles, attached to them

4) Endoabdominal fascia – deep to muscles, named depending on muscles overlying (eg. transversalis fascia). Parietal peritoneum underlies this layer

Muscles: all have long sheet-like aponeurosis form rectus sheath which encloses rectus abdominis and pyramidalis form linea alba in midline

Bladder is between peritoneum and transversalis fascia

Arcuate line: point where all flat ab muscles pass ant to rectus abdominus, half way between umbilicus and pubic bone

Nerves:

1) External oblique: from lat surfaces of last 8 ribs xiphisternum, linea alba, pubic symphysis, inguinal ligament, ant ½ iliac crest; become aponeurotic at MCL; inf margin forms inguinal ligament; interdigitates with serratus anterior (ribs 5-8) and latissmus dorsi (ribs 9-12); forms sup inguinal ring

a. Nerve: intercostal 7-11, subcostal, iliohypogastric and ilioinguinal2) Internal oblique: from ant 2/3 iliac crest, lat 2/3 inguinal ligament, lumbar fascia,

ileopectineal arch inf surfaces of ribs 10-12, costal margin, rectus sheath, linea alba; becomes aponeurotic at MCL; contributes to cremaster muscle

a. Nerve: intercostal 7-11, subcostal, iliohypogastric and II, 1st lumbar3) NEUROVASCULAR PLANE RUNS HERE contains4) Tranversalis abdominis: inner lower 6 costal cartilages, interdigitates with origin of

diaphragm, costal margin, ant 2/3 iliac crest, lat ½ inguinal ligament rectus sheath and linea alba; fibres run horizontally; is post to rectus abdominus until arctuate line, then anterior

a. Nerve: IC 7-11, SC, IH and II, 1st lumbar5) Rectus abdominis: pubic crest, tubercle and symphysis costal cartilages 5-7,

sternum and diaphragm; fibres run verticallya. Nerve: IC 7-11, SC

1) Thoracoabdominal nerves (T7-11) – runs between 2nd + 3rd layers then form:

a. Ant (7-11) and lat (7-10) cutaneous branches which pierce at ant axillary or parasternal line

2) Iliohypogastric nerve (L1) – emerges from upper lat psoas major crosses quadratus lumborum perforates TA then divides into lat and ant cutaneous branches; lat pierces IO and EO above iliac crest to skin of gluteal region, ant continues on between IO and TA and pierces EO near inguinal ring

3) Ilioinguinal nerve (L1) – emerges from lat border of psoas major crosses quadratus lumborum and iliacus perforates TA near ant iliac crest pierces IO accompanies spermatic cord through sup inguinal ring (does NOT pass through deep ring, only travels in part of canal); communicates with IH; supplies inner thigh, ant scrotum, root of penis; can be damaged during inguinal hernia repair

4) Genitofemoral nerve (L1-2) – genital branch enters deep inguinal ring to innervate cremaster; femoral branch enters thigh on ant surface of femoral artery and pierces fascia lata inf med half inguinal lig sensation

5) Subcostal nerve (T12) – runs along inf border of 12th rib then between 2nd + 3rd layers of muscles ant and lat cutaneous branch

Veins: 1) Superior epigastric and branches of musculophrenic vessels2) Inferior epigastric and deep circumflex iliac vessels drain to great saphenous, or superiorly to lat

thoracic, intercostal, and in thoracic veins3) Superficial circumflex iliac and superficial epigastric vessels4) Post intercostals and subcostal vessels

Arteries:

Post Abdominal Wall

Parietal peritoneum / Endoabdominal fascia / psoas or thoracolumbar or quadratus lumborum fascia / musclePsoas major: long, thick, fusiform; from transverse processes of L and bodies of T12-L5 passes deep to inguinal lig to lesser trochanter; innervated by lumbar plexus L2-4Iliacus: large, triangular; sup 2/3 iliac fossa, ant SI lig crosses SI jt to join tendon of psoas; innervated by femoral nerve

1) Internal thoracic arterya. Musculophrenic (supplies ant ab wall sup to umbilicus); gives off

ant intercostal arteries and med branches that anastomose with sup epigastric arteries

b. Superior epigastric – travels between RA and post rectal sheath; anastomosis with inf epigastric artery at umbilicus behind rectus muscle within sheath; supplies ant abdo wall and diaphragm

2) Aortaa. Post intercostal and subcostal arteries

3) Ex iliac arterya. Deep circumflex iliac – anastomose with lumbar arteries; deep to

lat ½ inguinal ligament between TA and IOb. Inf epigastric arises from ex iliac just above inguinal ligament

pierces tranversalis fascia ascends between RA and transversalis fascia then between RA and post rectus sheath; vas deferens/round ligament wind around lat + post aspects of artery; gives off cremasteric artery, pubic branch; anastomoses with sup epigastric, lower intercostal arteries and subcostal arteries

4) Femoral arterya. Superficial circumflexb. Superficial epigastric arteries – arises 1cm below inguinal

ligament, passes through femoral sheath, turns up infront of ligament, ascends in sup fascia of ab wall; supplies ant ab wall sup to umbilicus; anastomosis with inf epigastric

Lymphatics: deep ant ab wall above umbilicus has lymphatic drainage to mediastinal nodes; deep ant ab wall below umbilicus has drainage to ex iliac and para-aortic nodes

Quadratus lumborum: med ½ inf 12 rib and lumbar transverse process runs beside lumbar transverse processes iliolumbar lig and iliac crest

Subcostal nerve: ant rami T12 post to lat arcuate lig run on ant surface quadratus lumborum through transversus abdominis and in obliqueLumbar spinal: L1-5 post rami supply muscles and skin of back

Ant rami skin and muscles of lower trunk and limb

Inguinal Region

Inguinal ligament: extends from ASIS to pubic tubercle – formed by aponeurosis of ex oblique. Lacunar ligament: most medial; formed when some fibres pass posteriorly onto pectineal line of pubisPectineal ligament: the very lateral fibres of lacunar ligament as they run along pecten pubis. Reflected inguinal ligament: superior fibres cross linea alba and blend with contralateral ex oblique aponeurosisConjoint tendon: infmed fibres of in oblique merge with transversus abdominis

Inguinal canal: oblique passage 4cm long; lies parallel to inguinal ligament. Boundaries: post = transversalis fascia transversalis fascia conjoint tendon

ant = ex oblique and in oblique (for lat 1/3)roof = transversalis fascia in oblique ex obliquefloor = iliopubic tract inguinal ligament lacunar ligament

Opening at either side:a) Deep inguinal ring: entrance to inguinal canal; sup to inguinal ligament, lat to inf epigastric

artery, 2-4cm suplat to pubic tubercle; where transversalis fascia evaginated; ilioinguinal nerve DOES NOT pass through this

b) Superficial inguinal ring: exit; split in ex oblique aponeurosis suplat to pubic tubercle (med and lat crus)

Inguinal hernias:a) Indirect: protrude through inguinal ring; results of failed closure of deep inguinal ring; lateral to

inferior epigastric vessels; is within spermatic cord; more commonb) Direct: enters through weak Hesselbach’s triangle (bounded by RA medially, inguinal ligament

inferiorly, inf epigastric vessels suplat) in post wall; medial to inferior epigastric vessels; less common; lies outside inner 1-2 fascial coverings of spermatic cord

Contents:

R testicular vein enters IVC, L testicular vein enters L renal veinInternal spermatic fascia = tunica vaginalis communis

Artery: testicular artery come from ab aorta inf to renal arteries pass retroperitoneally obliquely over ureters and ex iliac arteries through deep inguinal ring into inguinal canal through sup ring

ScrotumLayers: heavily pigmented skin; dartos fascia (responsible for rugae, continuous with Scarpa fascia and Colles fascia); then ex spermatic, cremaster, in spermatic… then testisDivided by septum which is seen externally as scrotal raphaeBlood supply: int pudendal sup perineal (post scrotal branches)

Femoral sup and deep ext pudendal (ant scrotal branches)Inf epigastric cremasteric

Nerve supply: ant lat – genital branch of genitofemoral nerve (L1-2)Ant – Ilioinguinal nerve ant scrotal nervesPost – pudendal nerve (S2-4) posterior scrotal nervesInf – post femoral cutaneous (S2-3) perineal branches

TestisL testis hangs more inferiorly than RLayers: Tunica vaginalis (parietal and visceral)

Tunica albuginea (tough fibrous inner) forms mediastinum of testis and septae which form LobulesTunica vasculosa

Parts: seminiferous tubules (sperm produced) straight tubules rete testis pass up and backwards efferent ductules in head superiorly perforating tunica albuginea body of epididymis heading inferiorly epididymal duct in tail postinferiorly ductus deferens heads upwardsEpididymis lies on postlat border; sinus of epididymis lies between testis and pouchAppendix of testis lies on upper extremity just below head of epididymis; appendix of epididymis lies on head of epididymisBlood supply: testicular arteries – from antlat ab aorta, descend retroperitoneally INFRONT of ureters and ex iliacs enters inguinal canal at DEEP ringVenous drainage: veins from Pampiniform plexus ant to ductus deferens R testicular vein to IVC, L testicular vein to L renal

IN SPERMATIC CORD:Vas deferensArtery to vas – from inf vesicular arteryTesticular artery (from aorta)Testicular vein (from IVC/L renal)Cremasteric artery and vein (from inf epigastric)Pampiniform venous plexus (lie ant to vas)Sympathetic nerve fibresGenital branch of genitofemoral nerve (motor to cremaster, sensory to scrotal skin)LymphaticsVestige of processus vaginalis

IN CANAL BUT NOT SPERMATIC CORD:Cremasteric fasciaCremaster muscle – innervated by genital branch of genitofemoral nerveIlioinguinal nerve

Diaphragm

Peritoneal Cavity

Double-domed, muscular peripherally, converges on central tendon; attaches to inf margin of thoracic cage and sup lumbar vertebrae; R dome higherSup central tendon fuses with inf fibrous pericardium

Caval opening (T8-9): contains IVC, R phrenic nerve, lymphatic vessels; situated on R side and most superior;, through tendinous not muscular diaphragmAortic hiatus (T12): contains aorta, thoracic duct and azygous vein; formed by R+L crus united by median arcuate ligamentOesophageal hiatus (T10): contains oesophagus, ant and post vagal trunks, oesophageal branches of L gastric, lymphatic vessels; formed by R crusCrura: musculotendinous bundles that arise from ant bodies of L1-3 and IV discs; R crus is larger and longer than LMedial arcuate ligament covers psoas major, lateral arcuate lig covers quadratus lumborum.

Blood supply: internal thoracic pericardiophrenic and musculophrenic arteries, thoracic and ab aorta sup and inf phrenic arteriesVenous drainage: PCP and MP IT vein; SP and IP IVCNerve: motor supply solely from phrenic nerves

Structure From To ContainsOMENTA

Greater omentum Greater curvature of stomach and prox duodenum Ant transverse colon NB. Composed of 4 layers of peritoneum

Lesser omentum Lesser curvature of stomach and prox duodenum Liver Lies post to L lobe of liver, attached to liver in fissure for ligamentum venosum, attached to porta hepatis

MESENTERIESMesentery proper Small intestine Post abdominal wall Sup mesenteric artTransverse mesocolon Transverse colon, continuation of greater omentum Post abdominal wall Middle colic artSigmoid mesocolon Sigmoid colon Pelvic wall Sigmoid artsMesoappendix Mesentery of ileum Appendix Appendicular art

LIGAMENTSGastrosplenic Stomach, from greater omentum, L part Spleen Short gastric art, L gastro-omental

artGastrophrenic Stomach, from greater omentum, sup part DiaphragmGastrocolic Stomach, from greater omentum, apron part Transverse colonSplenorenal Spleen Kidney Splenic art, tail of pancreasHepatogastric Lesser curvature of stomach – makes lesser omentum LiverHepatoduodenal 1st 2.5cm duodenum - makes lesser omentum Liver Hepatic art, hepatic portal vein,

bile duct (portal triad)Falciform Ant Liver, ligamentum teres is obliterated remnant of

L umbilical vein and lies in free edge (upper border) of falciform ligament extending to umbilicus

Diaphragm, ant abdo wall Round ligament of liver, paraumbilical veins

Round Liver UmbilicusCoronary R lobe Liver, over sup aspect, split into sup an inf

layers; on either side of bare area of liverThoracic diaphragm

Ligamentum venosum Liver LiverPhrenicocolic L colic flexure Thoracic diaphragmL+R triangular R formed by fused parts of coronary ligament

Parietal: pain is well localizedVisceral: stimulated by stretching or chemical irritation; pain is poorly localizedPeritoneal cavity: potential space between parietal and visceral layersOmental bursa (lesser sac): large diverticulum of peritoneum. It communicates with greater sac through epiploic foramen situated post to hepatoduodenal ligament, ant to IVC and R crus of diaphragm, below liver, above D1.Compartments: Transverse mesocolon splits abdo into supracolic compartment (stomach, liver, spleen) and infracolic compartment (SI, colon). Infracolic compartment divided into L and R infracolic spaces by mesentery proper. Paracolic gutters allow communication between supra and infracolic compartments.Mesentery: double layer of peritoneum by invagination of peritoneum by an organ, so there can be neurovascular communication between organ and body wallBare area: allows passage of neuroV structures

L formed by falciform ligamentBroad Uterus Lat pelvic wall Mesovarium, mesosalpinx,

mesometriumOvarian Uterus Inguinal canalSuspensory Ovary Pelvic wall Ovarian artHepatorenal Postinf R lobe liver R kidney

Peritoneal fold: reflection of peritoneum with sharp border; infraumbilically there are 5 peritoneal folds (2 on each side and 1 in median plane)

1) 1 Median umbilical – covers median umbilical ligament (remnant of urachus), extends from urinary bladder to umbilicus

a. SPLIT BY SUPRAVESICAL FOSSAE2) 2 Medial umbilical – lateral; cover medial umbilical ligaments formed by obliterated umbilical arteries,

extends from in iliac arteries to umbilicusa. SPLIT BY MEDIAL INGUINAL FOSSAE

3) 2 Lat umbilical – lat to medial; cover inf epigastric arteries; extend from deep inguinal ring to each side of arcuate line

a. LAT INGUINAL FOSSA LAT TO LAT UMBILICAL FOLD

Peritoneal pouch:1) Rectouterine – separates rectum from uterus in women2) Rectovesical – separates rectum from bladder in men3) Vesicouterine – separates bladder from uterus in women

Factoid: in women peritoneum is not a closed sac, uterine tubes open into itaAlimentary Tract

Blood supply: from aorta celiac trunk, sup and inf mesentericVenous drainage: portal vein (from union of sup mesenteric and Splenic veins)

Oesophagus25cm; passes through oesophageal hiatus in R crus of diaphragm at T10, attached here by phrenicoesophageal ligament; ends at cardinal orifice of stomach L of T11; diaphragm forms inferior physiological sphincterBlood supply: L gastric artery (from celiac trunk), L inf phrenic arteryVenous drainage: submucosal veins L gastric vein portal venous system

oesophageal veins systemic venous systemNerve supply: oesophageal nerve plexus from vagal trunks and thoracic sympathetic trunks (from greater splanchnic nerves and periarterial plexuses) 3 constrictions

1) Cervical: at pharyngoesophageal junction caused by cricopharyngeus muscle

2) Thoracic: where crossed by arch or aorta and L main bronchus3) Diaphragmatic: where passed through oesophageal hiatus of diaphragm

Stomach

Ligaments: Hepatogastric ligament attaches to lesser curvature, contains L+R gastric arteriesGastrosplenal ligament attaches to greater curvatureGastrophrenic ligament attaches to post stomach

Nerve supply: ParaS: ant (L) vagal trunk ant gastric branches – lies on ant surface of oesophagus, runs on lesser curvature; controls pyloric sphincterpost (R) vagal trunks celiac branch post gastric branch– lies on post surface of oesophagus, runs on lesser curvature

Sym: greater splanchnic nerve celiac plexusBlood supply: Celiac trunk L gastric

Celiac trunk Hepatic artery R gastricCeliac trunk Splenic artery L gastroepiploic and short and posterior gastricCeliac trunk hepatic artery Gastroduodenal R gastroepiploic

Transpyloric plane: halfway between jugular notch and upper border of symphysis pubis; cuts through pylorus, tips of 9th costal cartilages, lower border L1, fundus of GB, neck of pancreas, origin of SMA and portal vein (ie splenic vein joining SMV), root of transverse mesocolon, DJ junction, D2, termination of spinal cord, spleen. R hilum kidney is just above, L hilum kidney is just below.

Duodenum

C-shaped, around head of pancreas; from pylorus to duodenojejunal junction; all but 1st part are retroperitoneal; 25cm long; fixed

Cardia: surrounds cardial orifice; at T10 to L of midlineFundus: limited inferiorly by horizontal plane of cardial orifice; sup part reaches 5th IC spacePyloric antrum leading to pyloric canal (at upper L1 to R of midline) to sphincter – contains more rugaeAngular incisure is notch in lesser curvatureLies to L of midlineGreater curvature goes up to 6th costal cartilageAnterior: abdo wall, L costal margin, diaphragm, L lobe liverPosterior: lesser sac, pancreas, transverse mesocolon and colon, L kidney, spleenSuperior: L dome of diaphragm; L and quadrate lobes of liver

Venous drainage: R and L gastric veins portal veinShort gastric and L gastroepiploic Splenic veinR gastroepiploic SMV

Lymph: accompany arteries; Sup 2/3 R+L gastric, short gastric and L gastro-omental vessels gastric or pancreaticosplenic nodes R side R gastro-omental pyloric nodeL side short gastric and splenic pancreaticoduodenal node

Lymph: ant lymphatic vessels pancreaticoduodenal nodes (situated along sup and inf PD arts) pyloric nodespost lymphatic vessels pass post to head of pancreas sup mesenteric lymph nodes

Jejunum and IleumJejunum in LUQ, ileum in RLQ; jejunum is 2/5, ileum 3/5; jejunum red, wide and thick walled, large valvulae conniventes (present in lower duodenum maximally), large villi, less lymph nodules, sparse arcade; ilium pink narrow and thin walled, few circular folds, multiple Peyer’s patches, multiple arcades

Mesentery: attaches jejunum and ileum to post ab wall (root at L side of body at L2 to R SI J); from duodenojejunal junction at L2 to ileocolic junction at R SI joint; passes duodenum, ab aorta, IVC, R ureters, R psoas major, R testicular and ovarian vessels

Blood supply: SMA – branches form arterial arcades vasa recta (straight arteries)Venous drainage: SMV – lies ant and to R of SMA

Part One: 5cm; at level of L1Passes R, up, back to neck of gallbladderAnt: quadrate lobe of liver and GB; sup: epiploic foramen; post: gastroduodenal artery, common bile duct and portal vein1st half has a mesentery (the ampulla, v mobile) and is attached to hepatoduodenal ligament and greater omentum

Part Two: 8cm; from L1-3From neck of gallbladder down to upper L4To L: IVC, common bile duct and head of pancreas; post: R kidney, renal vessels, IVC and psoas; ant: GB, duodenal impression on R lobe liver, SI and hepatic flexure of colonperitoneum on ant surface forms transverse mesocolonhas hepatopancreatic ampulla at major duodenal papilla (posteromedial)

Part Three:10cm; at level of L3Passes L and forward to infront of aortaPost: IVC, aorta and psoas major; ant: SMA and SMV, mesentery; sup: head of pancreas

Part Four:2.5cm; ascends to L2To L of aorta; Post to transverse colon, medial to L kidney and ureters, below body of pancreas duodenojejunal junction at level of L2, 2-3cm to L of midlineSupported by suspensory muscle of duodenum – from connective tissure around celiac artery to sup duodenoljejunal flexure

Blood supply: Before bile duct: celiac trunk Gastroduodenal artery sup pancreaticoduodenal artery; R gastricAfter bile duct : SMA inf pancreaticoduodenal artery

Venous drainage: Into portal vein via SMV and splenic vein

Nerve supply: celiac and sup mesenteric plexuses periartertial plexuses vagus, greater and lesser splanchnic

Lymph: pass to 4 groups of nodes: juxta-intestinal (near intestinal wall), mesenteric (along arterial arcades), and superior central (along prox SMA), ileocolic

Nerve: perivascular nerve plexus surrounds SMA and branchesSym: T8-10; sympathetic trunk and thoracic abdominopelvic splanchnic nerves sup mesenteric plexus synapse on celiac and sup mesenteric gangliaParaS: post vagal trunks synapse on myenteric and submucosal plexuses

Cecum and Appendix

Colon1.5m long; Can distinguish LI from SI by: omental appendices (not found in appendix, cecum or rectum), teniae coli (3 thickened bands of smooth muscle (mesocolic, omental and free; not found in appendix or rectum; converge at vermiform appendix), haustra, greater caliber, sacculated.

Descending colon – retroperitoneal; 30cmPost is L subcostal gonadal and ex iliac vessels; iliohypogastric, Ilioinguinal, lat femoral cutaneous and genitofemoral nerve

Ascending colon Narrower than cecum; retroperitoneal; 15cmBlood supply: SMA ileocolic, R colic and middle colic arteriesVenous drainage: ileocolic and R colic SMVLymph: epicolic and Paracolic nodes ileocolic and R colic nodes sup mesenteric nodesNerve: sup mesenteric plexus

Transverse colon Splenic flexure attaches to diaphragm via phrenicolic ligament; mesentery is transverse mesocolon; 45cmBlood supply: SMA middle colic, R colic artery; IMA L colic arteryVenous drainage: SMVLymph: middle colic nodes sup mesenteric nodesNerve: sup mesenteric plexus

Cecum: blind intestinal pouch below ileocaecal valve; ileocaecal valve is double fold of mucosa and circular muscle which acts as anti-reflux mechanism; situated above lat ½ inguinal ligament; rests on iliacus and psoas major; freely moves

Appendix: blind intestinal diverticulum, contains masses of lymphoid tissue, arises inf to ileocolic junction; has own mesentery (Mesoappendix) which carries appendicular artery; McBurney’s point is 1/3 distance from ASIS to umbilicus; most common position is retrocecal

Blood Supply: SMA ileocolic artery Appendicular arteryVenous drainage: ileocolic vein SMVLymph: ileocolic nodes sup mesenteric nodesNerve: from sup mesenteric plexus

Sigmoid colonHas long mesentery and therefore mobile; 15-45cm; crosses common iliac artery bifurcation, ureters and SI jt

Blood supply: IMA L colic and sigmoid arteryVenous drainage: IMVLymph: epicolic and Paracolic nodes intermediate colic nodes on L colic artery inf mesenteric nodesNerve: from ab aortic plexus via periarterial plexuses

Sym: from lumbar part of sympathetic trunk lumbar splanchnic nerves, sup mesenteric plexus and periarterial plexusesParaS: pelvic splanchnic nerves inf hypogastric nerve

Rectum

Retro and subperitoneal; commences at S3

SpleenOvoid, size of a fist; weight 150g; Fibrous capsule which form trabeculae internally splitting spleen into areolae which contain splenic pulp; Superior extremity at T11, lower extremity lies on splenic flexure; has notch on ant borderLigaments: Gastrosplenic – contains short gastric and L gastroepiploic Vessels

Splenorenal – contains splenic vessels Phrenicocolic – supports lower end

Surface: diaphragmatic visceral – gastric - stomach and pancreas contact

renal - narrower than gastric, renal and suprarenal contact

Relations: Posterior: 9-11th ribs Anterior: fundus of stomach – attached to greater curvature by Gastrosplenic ligament Inferior: splenic flexure – as it enlarges, glides infront of splenic flexure Medial: L kidney – attached by Splenorenal ligament

Blood supply: splenic artery divides into 5 branches that enter hilumVenous drainage: splenic vein joined by IMV unites with SMV behind pylorus to form portal vein

Nerve: from celiac plexus

Lymph: drain to pancreaticosplenal glands beside splenic artery post to pancreas celiac group

Factoids: in contact with lesser sac; projects into greater sac

Pancreas

Retroperitoneal in transpyloric plane; posterior to stomach, SMA and SMV, lesser sac, transverse mesocolon (attached to ant margin); inf to splenic artery; ant to L crus of diaphragm, psoas, R renal vein, L kidney, IMV, splenic and portal vein, aortaAmpulla of Vater: Wirsung duct opens into D2 at major duodenal papilla. Accessory pancreatic duct (Santorini) opens into duodenum at minor duodenal papillaBlood supply: celiac artery hepatic Gastroduodenal sup pancreaticoduodenal arteries head

SMA inf pancreaticoduodenal headSplenic artery provides branches body and tail

Venous drainage: pancreaticoduodenal splenic vein portal veinLymph: pancreaticosplenic and pyloric nodes hepatic nodes sup mesenteric or celiac nodesNerve: vagus and abdominopelvic splanchnic, passing from celiac and sup mesenteric plexuses

Liver

Head: enveloped by duodenum; on R of sup mesenteric vessels; ant to IVC, R renal artery and vein, L renal vein; bile duct lies in groove on post aspectUncinate process: posterior to SMANeck: lies ant to sup mesenteric vessels; ant surface is adjacent to pylorus; SMV and splenic vein join post to neckBody: to L of sup mesenteric vessels, over aorta, SMA, L suprarenal gland, L kidney, renal vessels and L2; post to omental bursaTail: ant to L kidney

Subphrenic recess = superior extension of peritoneal cavity; split into R + L recesses by falciform ligamentSubhepatic space – hepatorenal recess is postsup extension of subhepatic space. This communicates with R subphrenic recessLies from 7-11th ribs along midaxillary line

Surfaces:Superior: attached to diaphragm and ant ab wall by falciform ligament (ligamentum teres (round ligament) in free margin, obliterated umbilical vein; divides liver into L+R lobes); middle lies behind xiphoid processInferior: L lobe has gastric impression; quadrate lobe in relation to pylorus, sup duodenum and transverse colon; R lobe has colic, renal and duodenal impressionsPosterior: has deep mould for vertebral column; has suprarenal impressionPosterior and Inferior (visceral): split into lobes by

R sagittal fissure: formed from GB to groove for IVCSEPARATED BY CAUDATE AND QUADRATE LOBESJOINED BY PORTA HEPATIS` L sagittal fissure: separates R +L lobes; formed from fissure for

ligamentum teres (round ligament) and fissure for ligamentum venosum

Bare area demarcated by upper (continuous with falciform ligament) and lower layers (continuous with lesser omentum) of coronary ligament which meets to form R triangular ligament. L part of coronary ligament forms L triangular ligament. IVC fills groove in bare area on post aspect of liver.

Porta hepatis enclosed within lesser omentum: contains portal vein (lies central and posterior); L+R hepatic artery (lies L and anterior); L+R hepatic ducts (lies R and anterior); lymphatics and lymph nodes; autonomic nerves

Blood supply: Portal vein - supplies blood to parenchymaCeliac trunk common hepatic artery which gives off Gastroduodenal artery then becomes named hepatic artery proper bifurcates to supply R + L livers – supplies blood to non-parenchymal structures

Venous drainage: central veins collecting veins R, middle and L hepatic veins IVC

Lymphatics: Superficial in fibrous capsule, deep in connective tissueDeep formed in perisinusoidal spaces lymphatics in portal triads converge with superficial draining at porta hepatis hepatic nodes in lesser omentum celiac nodes chyle cisternSuperficial phrenic nodes at bare area posterior mediastinal nodesSome go to L gastric and parasternal nodes

Nerve: from hepatic plexus; sym from celiac plexuses, paraS from L vagus; enter at porta hepatis

Ligaments:Falciform: attached to diaphragm and R RA notch on ant margin to post surface; free edge contains round ligament and paraumbilical veinsCoronary – upper layer from upper bare area to diaphragm; lower layer from lower bare area to R kidney (hepatorenal ligament)Triangular (L+R): R formed by 2 layers of coronary ligament, passes from R bare area to diaphragm; L continuous with falciform ligament, from postsup L lobe to diaphragmHepatogastric – attaches from lesser curvature to L sagittal fissureHepatoduodenal – formed by lesser omentum

Lobes: R lobe split from L lobe by falciform ligament, L sagittal fossa and umbilical notchQuadrate lobe: bounded by ant margin, porta, fossa for GB, fossa of umbilical veinCaudate lobe: bounded by porta, fossa for IVC, fossa for ductus venosus

Gallbladder

Bile duct: runs between folds of lesser omentumBlood supply: cystic artery (prox), R hepatic artery (middle), post sup pancreaticoduodenal artery and Gastroduodenal artery (distal)Venous drainage: post sup pancreaticoduodenal vein portal veinLymph: cystic nodes near neck of GB, node of omental foramen and heptiac nodes celiac

Gallbladder: Lies on visceral surface of liver @ junction of R + L parts; ant to duodenumFundus – lies at levels of 9th costal cartilage in MCLBlood supply: Celiac hepatic R hepatic cystic artery (arises in angle where cystic and hepatic ducts meet, note that arteries lie post to ducts)Venous drainage: cystic vein portal vein or drain directly into liverLymph: hepatic nodes and cystic celiacNerve: ParaS: vagus

Sym: celiacVisceral afferent: celiacSomatic afferent: R phrenic

Kidneys

Suprarenal: R gland pyramidal in shape, more apical, makes contact with IVC and liver; L gland crescenteric, lies medially over kidney; veins and lymph leaves at hilum

Lymph: Renal and suprarenal vessels R+L lumbar

Retroperitoneal; surrounded by perinephric fat, which in turn is enclosed by renal fascia which is then surrounded by paranephric fat; lies at level of T12-L3; R kidney lies inf to L

R kidney: post to liver, D2, SI and R colic flexure; separated from liver by hepatorenal recess; on 12th ribL kidney: post to stomach, spleen, pancreas, jejunum and L colic flexure; on 11/12th ribsPosterior to kidneys is diaphragm, lumbocostal arches, psoas major, quadratus lumborum, tendon of TA, subcostal and upper lumbar arteries, thoracic, IH and II nerves.At hilum, renal vein is anterior to artery, which is anterior to renal pelvis.

Renal pelvis: @ L1; renal pyramids in renal medulla minor calyces (separated by renal columns in cortex) major calyces renal pelvis ureters (retroperitoneal) pass on psoas muscles over pelvic brim at bifurcation of common iliac arteries in lateral wall of pelvis

Ureters: pass ant to psoas major passing over pelvic brim at bifurcation of common iliac arteries run along lat wall of pelvis to enter bladder; 25-30cm long; contain no valves; pass post to gonadal and renal vesselsR ureters: post to descending duodenum, R colic and ileocolic vessels, mesentery, terminal ileum, to R of IVCL ureters: post to L colic vessels, sigmoid colon and mesenteryAre constricted in 3 places: junction of pelvices and ureters; where cross brim of pelvic inlet; during passage through wall of bladderOn X-ray they lie medial to tips of transverse processes, cross pelvic brim at SI jtBlood supply; usually renal arteries; sometimes testicular, ovarian, common iliac and ab aorta. Venous drainage: renal and gonadal

Middle ureters common iliacLower ureters common, ex and in iliac nodes

Nerve: Renal, ab aortic and sup hypogastric nerve plexusesFactoids: Has a short dilated region just prox to ex urethral meatus

Is horizontal in cross-section when emptyBulbous part is part of spongy urethra

Arteries

Ab Aorta: 13cm long Course: begins at aortic hiatus in diaphragm at T12 divides into L+R common iliacs at L4 2-3cm inf to umbilicus common iliacs follow medial borders of psoas to pelvic brim divides into in and ex iliacs. Internal enters pelvis, external follows iliopsoas and gives off inferior epigastric and deep circumflex iliac.Lies behind IVC superiorly, infront of IVC inferiorly

Relations:Anterior: celiac plexus, lesser omentum and stomach, body of pancreas and splenic vein, L renal vein, duodenum, mesentery, coils of SI Posterior: L lumbar veins, ant longitudinal ligamentRight: azygos vein, chyle cistern, thoracic duct, R crus of diaphragm, R celiac ganglion, IVCLeft: L crus of diaphragm, L celiac ganglion, duodenum

Coeliac Trunk:

Branches:Anterior midline / unpaired visceral alimentary tract

1) Celiac T12 22) SMA L1 33) IMA L3

Lateral / paired visceral urogenital and endocrine1) Suprarenal L1 42) Renal L1 43) Gonadal L2 5

Posterolateral / paired parietal diaphragm + body wall1) Subcostal L22) Inf phrenic T12 13) Lumbar L1-44) Median sacral (unpaired)

Superior Mesenteric Artery:

Covered by lesser omentum; on R is R celiac ganglion and caudate process of liver; on L is L celiac ganglion and cardia of stomach, below is pancreas

1- Splenic – runs above sup pancreas, above splenic vein, post to omental bursa, ant to upper pole of L kidney transverse Splenorenal ligament to hilum of spleen; supplies pancreas via pancreatic branches, spleen and greater curvature of stomach; is tortuous

a) L gastroepiploic – passes along greater curvature in greater omentum; supplies greater curvature

b) Short gastric – passes to fundus between layers of Gastrosplenic ligament; supplies fundus; anastomose with L gastric and L gastroepiploicc) Posterior gastric – along post wall of lesser omental sac to

Gastrophrenic ligament; supplies post wall and fundus2- L gastric – ascends to oesophageal hiatus post to omental bursa along lesser curvature to anastomose with R gastric; supplies distal oesophagus and lesser curvature of stomach

a) Oesophageal and cardia branch 3- Hepatic – passes to upper sup duodenum crosses portal vein anteriorly and ascends between layers of lesser omentum bifurcates into R + L hepatic arteries at porta hepatis; supplies liver, gallbladder, biliary ducts (lie on R), stomach, duodenum, pancreas, liver

a) R gastric – arises above pylorus runs along lesser curvature; supplies lesser curvature

b) Gastroduoedenal – descends between sup duodenum and neck of pancreas supplies pylorus divides at lower border of duodenum; supplies stomach, pancreas, D1, bile ducti. R gastroepiploic – passes along greater curvature of

stomach between layers of greater omentumii. Sup pancreaticoduodenal – divides into ant and post

branches on either side of pancreatic head; supplies prox duodenum and head of pancreas; anastomosis with inf branch from SMA

R hepatic gives off cystic artery

Supplies: from 2nd part duodenum splenic flexure; Relations: arises at L1; 1cm below celiac trunk; passes under neck of pancreas and splenic vein; anterior to L renal vein, 3rd part of duodenum and uncinate process of pancreas; to L of SMV; descends between layers of mesentery to RIF; passes infront of IVC, R ureter and psoas majorBranches: Inferior pancreaticoduodenal – opposite inf duodenum, courses between head of pancreas and duodenum; to head of pancreas and distal duodenum

Intestinal (12-15) – to ileum and jejunum; form archesIleocolic – to cecum and appendix; divides into inf and post branch; inf anastomosis with

SMA and gives off cecal, appendicular and ileal branches; sup anastomoses with R colic

R colic – to ascending colon; R internal spermatic vessel, R ureters and psoas major; divides into descending branch (anastomose with ileocolic) and ascending branch (anastomose with middle colic)

Middle colic – to transverse colon; arises just below pancreasBranches anastomose to form marginal artery along inner border of colon

Renal Arteries:

Suprarenal arteries also split into sup and middle suprarenals; arise opposite SMA

Arise between L1-2; below SMA; R is longer and lower than L; R passes posterior to IVC, R renal vein, head of pancreas and descending duodenum; L passes posterior to L renal vein, body of pancreas, splenic vein and IVC; each divide at hilum into 5 segmental arteries between renal vein and ureter: superior, anterosup, anteroinf, inferior, posterior segmental arteries as per segments; also give off inf suprarenals

Veins lies ANTERIOR to arteries. L vein longer, receives L suprarenal, gonadal and ascending lumbar veins. Passes ANTERIOR to aorta. Drain into IVC.

Internal Spermatic ArteryArise below renals, pass behind peritoneum, on psoas; R is infront of IVC and behind middle colic and ileocolic and terminal ileum; L is behind L colid and sigmoid arteries; each is INFRONT of ureters and ex iliac artery pass through deep ring

Inferior Mesenteric Artery:

Comes from ab aorta ½ way between origin of renal arteries and bifurcation, 3-4cm above bifurcation, at L3, behind inf border of D3, @ level of umbilicus; passes ant then to L of aorta, crosses ant to L common iliacSupplies: splenic flexure upper rectumBranches: L colic – supplies descending colon; runs to L behind peritoneum infront of psoas major, divides

into ascending (crosses infront of L kidney to anastomose with middle colic) and descending (anastomose with sigmoid)

Sigmoid (2-3) – run to L behind peritoneum, infront of psoas, ureter and in spermatic vessels Sup rectal – terminal branch; name changes as passes over pelvic brim; main source of blood

supply to rectum

Veins

Portal vein: formed by union of splenic vein and SMV ant to IVC and post to head of pancreas (@ level of L1) divides into L + R branches before enters liver at porta hepatis runs within hepatoduodenal ligament become hepatic sinusoids enter hepatic veins which drain into IVC.

Receives L gastric: runs in lesser curvature; drains stomachReceives oesophageal: drains oesophagus

R gastric: runs in lesser curvature; drains stomachCystic: drains GB

Portal-systemic anastomosis occur at inferior oesophagus, anal canal, paraumbilical area, in bare area of liver.

Splenic joins SMV portal: drains stomach, pancreas, LI, duodenum and spleen; is beneath splenic artery, is straight

Receives short gastric: fundus and L greater curvature; run in Gastrosplenic ligamentL gastroepiploic: drains stomachInferior and superior pancreaticoduodenal: drains pancreas and stomach

SMV joins splenic portal: drains stomach, pancreas, appendix, duodenum, jejunum, ileum and transverse colon

Receives R gastroepiploic: runs between 2 layers of greater omentum; drains stomachIinferior pancreaticoduodenal

Ileocolic: drains cecum, appendix and ascending colonIlealMiddle colic: drains transverse colonR colic: drains ascending colon

IMV drains into splenic vein: drains large intestine, sigmoid colon, rectumReceives L colic vein: drains descending colon

SigmoidSuperior rectal vein

Nerves

Sympathetic innervation

Abdominopelvic splanchnic nerves arise from ant rami and are presynaptic:T5-9 greater splanchnic nerve celiac ganglion liver, gallbladder, pancreasT10-11 lesser splanchnic nerve sup mesenteric ganglia suprarenal, kidney, gonadT12 least splanchnic nerve aorticorenal ganglia suprarenal, kidney, gonadL1-3 lumbar splanchnic nerve intermesenteric, inf mesenteric, sup hypogastic ganglia large and small bowel

Once synapsed in ganglia, pass via periarterial plexuses to organVisceral afferent (pain) accompany sympathetic fibres through post root to spinal sensory ganglia

Segments:T6-8 Spleen T6-L2 SuprarenalsT6-9 Stomach T10 – L1 Kidneys

Pancreas L2 Lower descending colonT8-12 Small intestine S2 Sigmoid colonT8 Cecum and ascending colon S4 RectumT10 Transverse colonT12 Descending colon

IVC: No valves (except gonadal); begins at L5 2.5cm to R of median plane, inf to bifurcation of aorta, post to prox R common iliac artery ascends on R of L3-5 on R psoas on R of aorta passes through caval opening of diaphragm at T8 Receives hepatic: drain liver

Renal: L longer than R because IVC on R body;

L renal vein and R IVC receive L suprarenal, lumbar, gonadalTesticular vein: have valves; emerge from back of testis form pampiniform plexus infront of ductus deferens unite to form 3-4 veins below superficial ring pass along inguinal canal form 2 veins which ascend on psoas lying on either side of in spermatic artery –> single vein drains.

Parasympathetic:Travel with visceral afferent (pain) fibres

1) Ant (L) and post (R) vagal trunks – pass through oesophageal hiatus on ant and post aspects; synapse at plexuses; supply foregut and midgut

2) Pelvic splanchnic nerve - arise from ant rami of S2-4; travel to inferior hypogastric plexus beside rectum; regulate emptying of urinary bladder and rectum, and erection (not ejaculation); supply hindgut and pelvis

Abdominal autonomic plexuses: networks of sym and paraS fibres surrounding aorta and major branches1) Celiac plexus: R+L celiac ganglia unite. ParaS from post vagal trunk; sym from greater and lesser

splanchnic nerves2) Sup mesenteric plexus: contains branch from celiac plexus and from lesser and least splanchnic nerves3) Inf mesenteric plexus: receives root from intermesenteric plexus and lumbar ganglia4) Intermesenteric plexus: between sup and inf; gives risde to renal, gonadal and ureteric plexuses5) Sup hypogastric plexus: receives root from intermesenteric and inf mesenteric plexuses; supplies

ureteric and testicular plexuses6) Inf hypogastric plexus: attached to sup by hypogastric nerves

Lumbar Plexus:

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Factoid: genitofemoral nerve runs on ant border of psoas major

Distinguishing Features

IN DUODENUM:

Interested In Getting Laid On Friday?Formed by ant divisions; in post part of psoas major, infront of transverse processes of lumbar vertebraeL1 divides into sup and post branches; L2-4 divide into ventral and dorsal divisions

Femoral: emerge from lat border of psoas deep to inguinal ligObturator: emerge from med border psoas, into lesser pelvis, through obturator foramen, to med thighLumbosacral trunk: over ala of sacrum descends into sacral plexusIH and II: post to med arcuate lig, ant to quadratus lumborum, pass through ex and in obliquesGenitofemoral: pierces psoas onto ant surface but deep to fascia, divides lat to iliac arteriesLat cut nerve of thigh: inflat on iliacus, deep to inguinal lig med to ASIS

S-cells: secrete secretin in duodenum in crypts of LieberkuhnI-cells: secrete cholecystokinin in duodenum release of enzymes and bile from pancreas and gallbladderBrunner’s glands: tubular submucosal glands in duodenum; produce alkaline secretion to protect duodenum from chime and active intestinal enzymes

IN ILEUM:Paneth cells: defense against microbes in ileum; secrete alpha-defensins known as cryptdin, lysozyme and phospholipase A2Peyer’s patches: secondary lymphoid organs, found in lower ileum