Abdomen & pelvis part I

All about anatomy of abdomen and pelvis

1. ABDOMEN & PELVIS PRESENTED BY :-Saru Gosain B.Sc.MIT 2017 MODERATOR:- Mr. Ranjit Kumar Jha ASSISTANT PROFESSOR

2. abdomen A bdomen (also called belly, tummy) is the part of the trunk below the diaphragm and above the pelvis at the pelvic inlet. 2 parts:- anterior abdominal wall and posterior abdominal wall .

3. Anterior abdominal wall Extends from the xiphoid process to the pubic symphysis anteriorly and thoracic cage to the gluteal region posteriorly. Consists of various muscles, peritoneal cavity and abdominal viscera

4. D ivided into 4 quadrants and 9 regions to describe the location of abdominal viscera or structure.

5. CONTENTS OF ABDOMEN PERITONEUM Large serous membrane lining the abdominal cavity. It is divided into Parietal peritoneum Visceral peritoneum Folds of peritoneum

6. CONTENTS OF ABDOMEN Parietal peritoneum lines the inner surface of the abdominal and pelvic walls and the lower surface of the diaphragm. Visceral peritoneum lines the outer surface of the viscera

7. Peritoneal folds connect viscera to the abdominal wall or to each other in or outside the peritoneal cavity. Eg :- mesentery at small intestine, mesocolon at colon, omenta at stomach and ligaments which are the double- layered folds of peritoneum. Viscera suspended in the cavity are intra-peritoneal whereas suspended outside with only one surface covered by the peritoneum are the retroperitoneal organs Retroperitoneal organs:- SAD PUCKER S= Suprarenal gland A= Aorta/IVC D= Duodenum (2 nd & 3 rd ) P= Pancreas except tail U= Ureters C= Colon (ascending and descending colon) K= Kidney E= Esophagus R= Rectum

8. CONTENTS OF ABDOMEN DIGESTIVE SYSTEM Oesophagus Stomach Small intestine Large intestine

9. Digestive system OESOPHAGUS The abdominal part of the esophagus is only about 1.25cm long which enters the abdomen through the esophageal opening of the diaphragm situated at the level of T10.

10. Stomach Also called gaster , ( greek belly) or venter Muscular bag farming the widest and most distensible part of the digestive tube. Intervenes between oesophagus above and duodenum below.

11. Situation Occupies epigastric , left hypochondriac and umbilical regions. Capacity In new born = 30-50ml In adult =1000-1500ml Shape In cadaver =sickle shaped In living =J-shaped

12. Presenting parts Two Orifices The cardiac orifice is joined by lower end of the oesophagus. The pyloric orifice open into the duodenum. Two Curvature The Lesser curvature and the greater curvature . Two surfaces The anterior/ anterosuperior surface faces forward and upwards. The posterior/ posteroinferior surface faces backward and downwards. Two parts 1. Cardiac part ; Fundus and body 2. Pyloric part Pyloric antrum (7.5cm) and pyloric canal(2.5cm)

13. Posterior-inferior surface is related to structures forming the stomach bed . Structures upon which the stomach rests; -Left crus of diaphragm -Left supra-renal gland -Anterior surface of left kidney -Tortuous splenic artery. -Anterior surface of pancreas. -Transverse mega colon. -Gastric impression of spleen(when distended stomach) Stomach bed

14. Arterial supply Left gastric artery(principal artery) Right gastric Short gastric Left gastro- epiploic Right gastroepiploic Posterior gastric artery.

15. venous drainage Right and left gastric veins-into the trunk of portal vein Short gastric and left gastro- epiploic veins-into splenic vein Right gastro- epiploic vein-into the trunk of superior mesenteric vein.

16. Small intestine Pylorus to ileocaecal junction Length : 6 m Duodenum = 25 cm Jejunum = upper 2/5 th Ileum = lower 3/5 th

17. Duodenum: fixed Retroperitoneal organ ( 2 nd & 3 rd part ) elongated ‘C' that lies between the level of the L1 to L3 in the supine position 20 DUODENUM

18. Divided into 4 parts First or Upper part:- 5 cm Second or vertical part:- 7.5-8 cm Third or horizontal part:- 10cm Fourth or Ascending part:- 2.5 cm

19. Extends from pylorus to superior duodenal flexure Length 5 cm In the radiograph taken after giving a barium meal, this part is seen as a triangular shadow and is referred to as duodenal cap Relations In front covered by peritoneum Related to quadrate lobe of liver Neck of gall bladder

20. 2 nd part of the duodenum Begins from the superior duodenal flexure opposite L1 vertebra Passes vertically downward to reach the inferior duodenal flexure opposite lower boarder of L3

21. 3 rd part of duodenum Begins from inferior duodenal flexure on the right side of lower border of 3 rd lumbar vertebra. 10 cm long Extends across the lower part of L3 Passes almost horizontal and slightly upwards in front of the IVC and ends in continuity with the fourth part in front of the abdominal aorta

22. 4 th part of duodenum About 2.5 cm long Extends to the duodeno - jejunal flexure in front of aorta Relation Peritoneal relation: Most of the part is retroperitoneal and fixed Terminal part is suspended by the uppermost part of the mesentery

23. Arterial supply Up to the level of opening of bile duct into 2 nd part of the duodenum, it is supplied by superior pancreaticoduodenal artery and below it is supplied by inferior pancreaticoduodenal artery. First part of duodenum receives additional supply from Right gastric artery Supraduodenal artery of Wilkie , which is branch of common hepatic artery Retroduodenal branch of gastroduodenal artery Some branches of right gastroepiploic artery

24. VENOUS DRAINAGE: splenic veins Superior mesenteric veins portal veins LYMPHATIC DRAINAGE: Pancreatoduodenal nodes NERVE SUPPLY : Sympathetic nerve: T9 & T10 parasympathetic nerve: Vagus nerve

25. Jejunum & Ileum Concerned with digestion & absorption . Hence, together known as small intestine proper . Extends from duodenojejunal flexure to ileocaecal junction Upper 2/5 th : jejunum Lower 3/5 th : ileum Are suspended from posterior abdominal wall by mesentery, hence mobile.

26. ARTERIAL SUPPLY: Jejunal and ileal branches of the superior mesenteric artery. Vasa recta supplies to the glands and villi. LYMPHATIC DRAINAGE: Mesenteric lymph nodes NERVE SUPPLY : Sympathetic T9 to T11

27. Feature Jejunum Ileum Wall Thicker and more vascular Thinner and less vascular Lumen Wider and often empty Narrower and often loaded Mode of blood supply Jujunal arteries form one or two arterial arcades; the vasa recta arising from it is longer and fewer Form three or more arcades; vasa recta are shorter and more numerous Mesentry Fat is less abundant therefore translucent windows are found between the vasa recta and the window are rectangular More abundant therefore translucent windows are usually not observed. If present they are rectangular Plicae circularis Larger and more closely set Smaller and widely separated (fold are absent in terminal 6 inch ) Solitary lymphatic follcles absent present Peyer’s patches Absent present

28. Fig: plicae circulares of the jejunum(A) and ileum(B).

29. Large intestine Length: 1.5 m Extends from caecum in right iliac fossa to anus in perineum. Apart from transverse colon & sigmoid colon , it is more fixed in position than small intestine . 32

30. Four Parts Cecum & Appendix Colon Ascending colon- 12.5 cm Transverse colon- 50cm Descending colon- 25cm Sigmoid colon- 37.5cm Rectum Anal Canal 33

31. Features of large gut 1 . TAENIAE COLI- three thick bands produced by the aggregations of the longitudinal muscles of the large gut. Taenia libera – on anterior surface Taenia mesocolica - on posterio -medial surface Taenia omentalis - posterio lateral surface

32. 2. SACCULATIONS 3 . APPENDICES EPIPLOICAE – are peritoneal pouches containing fat present in the entire large gut expect caecum, appendix and rectum

33. CAECUM Large blind sac situated in the right iliac fossa, above the lateral half of inguinal ligament. 6 cm long and 7.5 cm broad VERMIFORM APPENDIX Worm like tubular diverticulum arises from postero - medial wall of the caecum, 2cm below ileo-ceacal junction

34. Positions of appendix 11 o clock – paracolic 2 % 12 Clock - retrocolic ,commonest type 2 Clock - splenic type 1-2 % 3 CLOCK - promontoric rare 4 clock – pelvic 30% second commonest 6 clock – mid inguinal

35. ASCENDING COLON extends from the caecum to the right colic flexure. TRANSVERSE COLON extends from the right colic flexure to the left colic flexure. DESCENDING COLON extends from the left colic flexure to the sigmoid colon.

36. ARTERIAL SUPPLY Marginal artery of Drummond which is formed by colic branches of superior and inferior mesenteric arteries. LYMPHATIC DRAINAGE Epicolic lymph nodes Paracolic nodes Intermediate nodes Terminal nodes NERVE SUPPLY Sympathetic supply from coeliac and superior mesenteric ganglia (T11 to L1) Parasympathetic supply from vagus

37. HEPATO-BILIARY APPARATUS Liver Right and left hepatic ducts Common hepatic duct Gallbladder Cystic duct Bile duct

38. Liver Second largest organ of the body and largest gland of body. It consists of: Exocrine part – secretes bile and Endocrine part– liberate glucose from glycogen, most of plasma protein and heparin directly into blood. Weight: 1200 to 1500 gm, or 4-5% of body weight. Location: whole of the right hypochondrium, the greater part of epigastrium, and extends into the left hypochondrium

39. Five surfaces Anterior Posterior Superior Inferior & Right lateral b)1 prominent Border: - inferior c) 2 lobes

40. Lobes of liver Anatomically liver is divided into Rt and Lt lobe. Rt . Lobe is much larger than left lobe and forms 5/6 th of liver and presents the caudate and quadrate lobes. The left lobe is smaller(1/6 th ) and ends in a thin apex.

41. Ligaments of liver 5 peritoneal fold (false ligaments): Falciform lig Coronary lig Rt triangular lig Lt triangular lig Lesser omentum 2 developmental (true ligaments); Ligamentum teres hepatis Ligamentum venosum

42. Porta Hepatis deep transverse fissure (5cm long) gateway of liver present in inferior surface of Rt lobe. The portal vein, hepatic artery and hepatic nerve plexus enters. The right and left hepatic ducts and some lymph vessels leaves .

43. Peritoneal relations Liver is covered by peritoneum Except : -bare area -groove for IVC -fossa for gall bladder -coronary ligaments -lesser omentum

44. Arterial supply Liver receive dual blood supply: 20% blood supply from hepatic artery and 80% through portal vein. Before entering liver both divide into Rt and Lt branches  within liver it divide into segmental vessels  interlobular vessels which run along portal canals  further branch and open into hepatic sinusoid  central vein.

45. Venous drainage Hepatic sinusoid  central vein  interlobular veins  sublobular veins hepatic veins finally drain into IVC.

46. LYMPHATIC DRAINAGE: caval , hepatic, paracardial and coeliac nodes. NERVE SUPPLY : from hepatic plexus which contain both sympathetic and parasympathetic (vagal fiber).

47. right and left hepatic ducts Emerge at porta hepatis from the right and left lobes of the liver.

48. Common hepatic duct Formed by union of Rt and Lt hepatic ducts . About 3 cm long J oined at right side by cystic duct to form bile duct .

49. Gall bladder pear shaped reservoir of bile. Situated in fossa on inferior surface of Rt lobe of liver. Dimensions : 7-10cm long and 3cm wide . Capacity : 30-50ml. Cystic artery, arising from Rt hepatic artery supplies GB, along with cystic duct, hepatic ducts and upper part of bile duct.

50. Cystic duct BILE DUCT Formed by union of cystic and CHD It is 8cm long and 6mm in diameter. It comes in contact with pancreatic duct to form hepatopancreatic ampulla or ampulla of Vater . Distal constricted end of ampulla open into summit of major duodenal papilla. Sphincter of oddi It is 3- 4cm long. It begins at neck of gall bladder and ends by joining common hepatic duct to form bile duct.

51. Lymphatic system L ymphatic organ connected to the blood vascular system Location Left hypochondrium, and partly in the epigastrium Dimension 2.5cm thick, 7.5cm broad, 12.5cm long7 ounces in weight, and is related to 9 th to 11 th ribs. spleen

52. External features Two ends Anterior or lateral Posterior or medial Three borders Superior Inferior Intermediate Two surfaces Diaphragmatic visceral Two angles Anterobasal Posterobasal Ligaments Gastrosplenic Lienorenal Phrenicocolic Impressions Gastric Renal Colic pancreatic

53. ARTERIAL SUPPLY Splenic artery, branch of coeliac artery VENOUS DRAINAGE Splenic vein LYMPHATIC DRAINAGE Pancreaticosplenic nodes NERVE SUPPLY Sypathetic fibres derived from the celiac plexus

54. PANCREAS Gland that is partly exocrine and partly endocrine. The exocrine part secrets digestive pancreatic juice and the endocrine part secretes hormones e.g. insulin. Location Posterior abdominal wall, at the level of L1 and L2. Endocrine system

55. Size 15-20 cm long, 2.5-3.8 cm broad and 1.2-1.8 cm thick and weighs about 90g. ARTERIAL SUPPLY Pancreatic branches of the splenic artery Superior pancreaticoduodenal artery Inferior pancreaticoduodenal artery

56. VENOUS DRAINAGE Veins drain into splenic, superior mesenteric and portal veins. LYMPHATIC DRAINAGE Pancreaticosplenic , coeliac and superior mesenteric groups of lymph nodes NERVE SUPPLY Vagus or parasympathetic nerve Splanchnic sympathetic nerve

57. ADRENAL Gland Location : in the epigastrium, on posterior abdominal wall behind peritoneum, at the upper pole of kidney in 11 th intercostal space and 12 th rib. Size :5×3×1cm, 1/3 rd size of kidney at birth and 1/30 th in adult. Weight : about 5g, 1/10 th formed by medulla Shape : Rt. triangular or pyramidal and Lt. semilunar in shape

58. arterial supply There are usually three arteries that supply each adrenal gland: The superior suprarenal artery is provided by the inferior phrenic artery The middle suprarenal artery is provided by the abdominal aorta The inferior suprarenal artery is provided by the renal artery.

59. VENOUS DRAINAGE The right suprarenal vein drains into the inferior vena cava The left suprarenal vein drains into the left renal vein LYMPHATIC DRAINAGE Lymphatics from the suprarenal gland drain into the lateral aortic nodes NERVE SUPPLY Suprarenal medulla has a rich nerve supply through preganglionic sympathetic fibers.

60. URINARY SYSTEM Kidney-2 Ureter-2 Urinary bladder Urethra

61. Kidney P air of excretory organ situated on the posterior abdominal wall retroperitonally . O ccupy the epigastric, hypochondriac, lumbar and umbilical region . Extends from T 12 -L 3 Rt kidney is slightly lower than the Lt.

62. SIZE AND WEIGHT 11cm long, 6cm broad and 3cm thick W eighs 150 gram in male and 135 gram in female . Extent:- T12-L3 EXTERNAL FEATURES Two poles - upper pole - lower pole Two surfaces –anterior -posterior Two borders- lateral -medial

63. Relations of kidney Upper pole of each kidney is related to the corresponding supranenal gland Medial border of each kidney is related to:- The suprarenal gland , above the hilus , and To the ureter below the hilus Posterior relations:- related to the following structures:- Diaphragm Medial and lateral arcuate ligaments Psoas major Quardratus lumborum Transversus abdominis Subcoatal vessels Subcostal, iliohypogatric and ilioinguinal nerves

64. Other relations of right kidney 12th rib Right suprarenal gland Liver Second part of duodenum Hepatic flexure of colon Small intestine

65. Other relations of left kidney 11 th and 12 th ribs Left suprarenal gland Spleen Stomach Pancreas Splenic vessels Splenic flexure and descending colon Jejunum

66. Capsules /coverings of kidney The fibrous capsule Perirenal or perinephric fat Renal fascia Pararenal or paranephric fat

67. LYMPHATIC DRAINAGE Lymphatics of kidney drain into lateral aortic node NERVE SUPPLY Kidney is supplied by renal plexus It contains sympathetic T10-L1 fibers which are chiefly vasomotor The afferent nerves of kidney belong to the segments T10-T12

68. ureter These are pair of muscular tubes (25 cm) that are continuous superiorly with the renal pelvis. Consists of three parts:- Abdominal part Pelvic part Intramural part

69. DIMENSION 10 inch long of which upper half 5 inch lies in the abdomen and lower half 5 inch in the pelvis measures about 3mm in diameter but it is slightly constricted at 5 places At the pelviuretric junction At the brim of lesser pelvis Point of crossing of ureter by ductus deference or broad ligament of uterus. Intravesical course and At the trigone of urinary bladder

70. BLOOD SUPPLY Upper part- renal artery Middle part- from aorta Pelvic part- vesical , middle rectal or uterine vessels NERVE SUPPLY Sympathetic- T10-L1 Parasympathetic- S2-S4

71. Posterior abdominal wall Includes following Abdominal aorta Inferior vena cava Abdominal parts of the azygos and hemiazygos veins Lymph nodes of posterior abdominal wall and cisterna chili Muscles of the posterior abdominal wall and thoracolumbar fascia Nerves of the posterior abdominal wall including lumbar plexus and the abdominal part of autonomic nervous system

72. Bones in relation to abdomen Lumbar vertebrae-5 Sacrum-1 (formed by fusion of 5 bones) Coccyx-1 (formed by fusion of 4 bones) Bony pelvis

73. Lumbar vertebrae There are 5 lumbar vertebrae, of which the first four are typical, and the fifth is atypical Lumbar vertebrae is identified by Its large size The absence of costal facets on the body and The absence of foramen in transverse process

74. Typical features of lumbar vertebrae The body is large, kidney-shaped The vertebral foramen is triangular in shape, and is larger than in the thoracic region but is smaller than in cervical region The pedicles are short and strong The alminae are short, thick and broad The spine forms a vertical quadrilateral plate, directed almost backwards and only slightly downwards. The transverse process are thin and tapering The superior articular processes lie farther apart than the inferior The inferior articular process lie nearer to each other than the superior.

75. aTypical features of lumbar vertebrae T he transverse processes are thick, short and pyramidal in shape. The distance between the inferior articular processes is equal to or more than the distance between the superior articular processes. The spine is small, short and rounded at the tip The body is the largest of all the lumbar vertebrae. The pedicles are directed backwards and laterally. The superior articular facets look more backwards than medially, and the inferior articular facets look more forwards t han laterally, as compared to other lumbar vertebrae

76. sacrum Large, flattened, triangular bone formed from the fusion of five sacral vertebrae Male sacrum Female sacrum Longer and narrower, i.e., the average sacral index is 105 Shorter and wider, i.e., the average sacral index is 115 The width of the body of the first sacral vertebrae is greater than that of each ala in the male The two are equal The dorsal concavity of auricular surface is less marked in male More marked The concavity on the ventral aspect of sacrum is more uniform, and is shallower in males The concavity is irregular especially between S1 and S2 and between S3 and S4 The sacrovertebral angle and the size of pelvic cavity is less More

77. coccyx Small triangular bone formed by fusion of four rudimentary coccygeal vertebrae