HSS2011 Human Anatomy 2024 Module 2-1 Abdomen & Pelvis PDF

HSS2011 Human Anatomy - Module II series: 1. Regional anatomy of the Abdomen & Pelvis 2. Organs of the Digestive system 3. Organs of the Urogenital system Dr. Fiona Chen, HTI 2024...

HSS2011 Human Anatomy - Module II series: 1. Regional anatomy of the Abdomen & Pelvis 2. Organs of the Digestive system 3. Organs of the Urogenital system Dr. Fiona Chen, HTI 2024 1  Regions of the human body Head & Neck Upper limb Upper limb Thorax A Abdomen & Pelvis Umbilicus Lower limb Lower limb Perineum 2  Learning outcome At the end of the lecture, students should be able to: 1) Delineate the abdomen & pelvis into quadrants and sub-regions. 2) Define the boundaries of the abdominal cavity and pelvic cavity. 3) Describe the major structures piercing the diaphragm. 4) Describe the basic gross anatomy of the Stomach, Small intestine, Large intestine, Liver, Gallbladder, Pancreas, Spleen, Kidneys and Ureters. A 5) Develop a sense of understanding of the peritoneum and its function. 6) Establish an understanding of the arterial blood supply, venous drainage, lymphatic drainage and nerve intervation of the abdomen. 3  Surface anatomy of the abdomen Left midclavicular bone Clavicular (collarbone) Thorax Diaphragm #Y Xiphoid sternum Grib) Costal margin Inferior margin of the tenth costal cartilage Abdomen Iliac crest Umbilicus Anterior superior iliac spine white line Inguinal ligament Linea alba Pubic symphysis Lower limb 4  Clinical subdivisions Skin is the largest organ of the human body. Mid-line Right Upper Left Upper Quadrant Quadrant (RUQ) RUQ LUQ (LUQ) Right Lower RLQ LLQ Left Lower Quadrant Quadrant (RLQ) (LLQ). The four quadrants are delineated by two perpendicular lines that intersect at the umbilicus. 5  Anatomical subdivisions clavicle Mid-clavicular lines Right ALE Leftcartilage I Epigastric below , costal region Hypochondriac region region hypochondriac Transpyloric plane (L1) Umbilical Right lumbar region region Left lumbar region Transtubercular plane (L5) Right inguinal region 7 Pubic Left inguinal region / (Hypogastric) region lumber retebrae The umbilicus is located at the vertebral level of L3/L4. 6  Mapping to internal organs Diaphragm: separates the Thorax & the Abdomen Anatomical subdivisions Clinical subdivisions 7  Mapping to internal organs Sp Anterior view Posterior view Posterior view 8 Regional anatomy of the abdomen & pelvis Topic of Interest 1.1 The Abdominal and Pelvic Cavity 1.2 The Anterolateral Abdominal Wall 1.3 The Posterior Abdominal Wall 1.4 The Great Vessels at the Posterior Abdominal Wall 1.5 The Peritoneum and Peritoneal Cavity 1.6 Anatomy of the Gastrointestinal Tract 1.7 Anatomy of the Accessory Organs 1.8 Anatomy of the Kidneys & Ureters 9  HSS2011 Human Anatomy Regional Anatomy of the Abdomen & Pelvis 1.1 The Abdominal and Pelvic Cavity 10  The Abdominal cavity & pelvic cavity Dorsal cavity: Ventral Cavity Brain layer spinal cord Oserous Abdominal cavity III Avisceralese AAA A Coronal section Sagittal section 11  Thoracic outlet (inferior view)  R L xiphoid process inlet costal margins 12th thoracic vertebra bounded by the diaphragm outlet T12 Not a flat plane! costal 12th rib margin 12  The diaphragm (inferior view) Inferior Right Left abdominal aorta. ↳ start from ascending aorla. 13  The diaphragm as the abdominal inlet Anterior view Left Lateral view inferior vena cava (IVC) D Esophages inferior vena cava (IVC) oesophagus 7connective aorta tissue tendoneous Abdominal aorta Important structures passing through the openings: related to diaphagm. caval hiatus T8 (central tendon) Inferior vena Cava (IVC); right phrenic nerve = Opening BES. oesophageal hiatus T10 Oesophagus, vagus nerves, oesophageal branches of the gastric vessels and lymphatics pair aortic hiatus T12 (between crura) Abdominal aorta, azygos vein, thoracic duct not in in vs nemiazygos vein. 14  HSS2011 Human Anatomy Regional Anatomy of the Abdomen & Pelvis 1.2 The Anterolateral Abdominal Wall 15  Muscles of the antero-lateral abdominal wall 4. Rectus abdominus & tendinous intersection linea alba linea alba 1. External oblique muscle 2. Internal oblique muscle 3. Transversus abdominis (Skin removed) (External oblique removed) (Internal oblique removed) inner > outer dense connective tissue. Each of the muscles (1-3) has a fibrous part known as aponeurosis - (green color), which adheres to one other when approaching the mid-line of the abdominal wall. 16  An overview of the anterolateral abdominal wall Linea alba is a tendinous, fibrous raphe that runs vertically down the midline of the abdomen formed by the interlacing aponeuroses of three abdominal muscles. Linea alba Central Live 1.External oblique 2.Internal oblique 3.Transversus abdominis Inguinal ligament Superficial inguinal ring of Rectus abdominis the inguinal canal Rectus sheath 17 like a coverage of venival muscle.  HSS2011 Human Anatomy Regional Anatomy of the Abdomen & Pelvis 1.3 The Posterior Abdominal Wall 18  The abdominal walls Anterior view Anterolateral abdominal wall: Skeletal muscles L1 /camber L2 Costal margin L3 vertebrae· L4 L5 Posterior abdominal wall Lumbar spine, skeletal muscles 19  Lumbar vertebrae Intervertebral disc & supporting ligaments size : Lumber vertebrae is large. 6 9 8 12 5 3 4 10 11 2 7 3 1 6 L4 1 Similar to thoracic vertebral 1. Vertebral body 7. Intervertebral disc 2. Pedicle 8. Anterior longitudinal ligament 3. Lamina 9. Posterior longitudinal ligament 4. Superior & inferior articular process 10. Ligamentum flavum 5. Transverse process 11. Interspinous ligament 6. Spinous process 12. Supraspinous ligament 20  The posterior abdominal wall Anterior view Posterior view Hiatus for abdominal aorta Crura of diaphragm: (Right crus & Left crus) deep muscle Quadratus lumborum L3 Psoas major muscle bone pelvic Sciatic nerve Iliacus muscle Inguinal ligament Iliopsoas muscle Showing Quadratus lumborum y inserts to the lesser trochanter of femur (See Lower Limb Anatomy) end pe is lower limb. Note the posterior abdominal wall is not the Back of the body. 21 (inside the abdominal cavity  The Deep (Intrinsic) muscles of the Back -divide 11 Spinotransversales Posterior view 3 layer Splenius capitis/ cervicis Innervation: Posterior rami of segmental spinal nerves Others: Transversospinalis Intertransversarii Short Muscle Transversospinales Spinalis ↑ Semispinalis Longissimus (thoracis) En Iliocostalis (lumborum) Quadratus lumborum Erector spinae (see Posterior abdominal wall) emp Multifidus Muscular action: extensors of spine 22  The skeletal muscles forming the boundaries of the abdominal cavity Right side Left side Abdominal cavity abdominal cavity Psoas major posterior abdominal Transverse section viewed from inferior wall posterior Erector spinae (a deep muscle of the back) 23  HSS2011 Human Anatomy Regional Anatomy of the Abdomen & Pelvis 1.4 The Great Vessels at the Posterior Abdominal Wall 24  Major structures related to the posterior abdominal wall Diaphragm Esophagus (cut) Left adrenal gland Inferior vena cava 11 H Left kidney Right adrenal gland Left renal vein Right kidney Superior mesenteric artery Quadratus lumborum Left ureter Iliacus muscle Abdominal aorta Psoas major muscle Left common iliac artery Parietal Peritoneum (cut) Gonadal artery & vein Rectum (cut) Male = testicular Urinary bladder Female = ovarian 25  Anatomy of the abdominal aorta 1. Ascending aorta in middle mediastinum (not shown) Clavicle 2. Arch of aorta (Aortic arch) in superior mediastinum 3. Descending (part of) aorta in posterior mediastinum Inferior phrenic artery Diaphragm Th 4. Abdominal aorta Branch 1) Celiac trunk 14 Common iliac artery 2) Superior mesenteric artery (SMA) ↓ - external 3) Inferior mesenteric artery (IMA) internal Femoral artery Describe the location of the heart At the middle part of inferior mediastinum The abdominal aorta extends from T12 to L4. 26  Interior vena cara is longer. Venous drainage of the Abdomen & Pelvis compare abdomial cora. (4) Inferior vena cava (9) 78 Hepatic veins Azygos venous system Right renal vein start from lumber region atrium right L5 Common iliac vein External iliac vein Pelvic organs  Internal iliac vein Internal iliac vein Lower limb  External iliac veins Inferior vena cava (IVC) extends from L5 to T8. 27 The lymphatic drainage of the abdomen & pelvis Have immune. response 25% 75% lymphatic pathway 28 Schematic of the sympathetic nervous system send neuve fibre. 29 Schematic of the parasympathetic nervous system shorter. 30  The comparisons between sympathetic and parasympathetic divisions Feature Sympathetic Parasympathetic Origin in CNS Thoracolumbar Craniosacral (T5- T9 Celiac ganglion (Vagus nerve (X) T9-T10 Celiac and superior mesenteric ganglion S2-S4) Lumbar – Interior mesenteric ganglion) Location of Paravertebral ganglia adjacent to spinal column Terminal ganglia near ganglia and prevertebral ganglia anterior to it or within target organs Fiber lengths Short preganglionic Long preganglionic Long postganglionic Short postganglionic Effects of system Often widespread More local and specific 31  The abdominal aorta & the inferior vena cava 1.The abdominal aorta begins at T12 and ends at L4. 2.Name two terminal branches of the abdominal aorta. external iliac artery and inferior iliac artery 3.Name three branches of the abdominal aorta that supplies the GI tract and associated organs. celiac trunk, superior and inferior mesenteric artery 腎上腺 4.Name the blood supply to the kidneys and adrenal glands on both sides. renal artery and Adrenal Arteries 5.Name the gonadal artery of the male and the female respectively on both sides. testicular arteries and ovarian arteries 6.The IVC begins at L5 and terminates at L8. 7.The right gonadal vein drains directly into IVC; the left gonadal vein drains into the left renal vein. 32  HSS 2011 Human Anatomy Regional Anatomy of the Abdomen & Pelvis 1.5 The Peritoneum and Peritoneal Cavity HA HE HA 33 Peritoneum & its relationships with organs Superior Parietal peritoneum back/posterior Retroperitoneal I space Visceral peritoneum abdominal e.g kidney , aorta. Retroperitoneal Peritoneal cavity structure/ organ Anterior Posterior 2 parietal peritoneum merge. Intraperitoneal organ Peritoneal fold: Transversalis fascia Inferior 34  Intraperitoneal vs. Retroperitoneal structures Intraperitoneal: Retroperitoneal: Stomach Suprarenal Glands ↑ Appendix enter Aorta/IVC Liver connect the. major part Duodenum (2nd-4th) Transverse colon Pancreas Duodenum (1st) (head, neck&body) Small intestines * Ureters following by Kidney. Jejunum&Ileum Colon Pancreas(tail) veryclose to spleen (ascending&descending) Rectum (upper 3rd) Kidneys Spleen Esophagus Sigmoid colon Rectum * Epiploic foramen peritoneum Greater sac Lesser sac Peritoneal cavity Female 35  Peritoneal folds provide limited movement. Median section evitorence form by t The peritoneal folds envelope various parietalFalciform ligament Diaphragm abdominal organs, holding them to the dorsal surface of the body wall. (2 layers Lesser omentum Within these folds are: blood vessels, un Stomach lymphatic vessels, and nerves that Pancreas innervate the organs with which they Transverse Duodenum mesocolon are in contact, supplying their adjacent Transverse organs. Mesentery colon proper sinterior pan of stomach & transverse colon) Greater > - posterior abdominal wall omentum ~ reverse Sigmoid 14 layers mesocolon Parietal peritoneum Rectum the organs are enveloped by the Small Urinary intestine peritoneal folds bladder Uterus 36  Peritoneal folds Falciform ligament Because of fat. I stabalize small intestine. Mesocolon is identified as the “mesentery of the colon” where the transverse colon and sigmoid colon are suspended by their corresponding mesocolon. 37  The greater & lesser omentum Omentum is a fold of peritoneum extending from the stomach to adjacent abdominal organs: “Liver” Greater omentum –suspended from the greater curvature Lesser of the stomach and attached to the anterior surface of the omentum transverse colon, loosely covers the small intestine as an apron (a ventral mesentery). Greater omentum Lesser omentum – joining the lesser curvature of the stomach and the first part of the duodenum to the liver (a dorsal mesentery).. The Greater omentum consists of up to 4 layers of fused visceral peritoneum. 38  Peritoneal folds and abdominal viscera Falciform ligament linked to small intestine Mesenteries: suspends the small Greater & lesser omentum intestine, portions of large intestine. 39  The relationship between abdominal organs and the peritoneum Posterior A cross-section of the abdomen R L Anterior ventro 40  The five major peritoneal folds Greater Apron-like structure that lies superficial to the small intestine omentum and transverse colon; a site of fat deposition in people who are overweight. Lesser Suspends the stomach from the inferior border of the liver; omentum provides a pathway for structures connecting to the liver. G Falciform Anchors the liver to the anterior abdominal wall and inferior ligament border of the diaphragm. An Mesentery Vertical band of tissue anterior to the lumbar vertebrae and anchoring all of the small intestine except the initial portion (the duodenum). Ety -A Mesocolon Attaches two portions of the large intestine (the transverse and sigmoid colon) to the posterior abdominal wall. 41  Description for peritoneum The peritoneum is the serous membrane in the abdominal cavity that covers abdominal organs and forms double sheets of mesenteries that suspend many of the digestive organs. Visceral peritoneum covers the external surface of an organ. Parietal peritoneum lines the abdominal wall. Peritoneal cavity is the potential space between the parietal and visceral peritoneum. Serous fluid secreted by the cells of the thin squamous mesothelium lubricates the membrane and reduces abrasion and friction between organs. Inside the peritoneal folds, there are: - Blood vessels (artery, vein) - Nerve fibers - Lymphatic vessels - Visceral adipose tissue (fat) 42  HSS 2011 Human Anatomy Regional Anatomy of the Abdomen & Pelvis 1.6 Anatomy of the Stomach, Small Intestine & Large Intestine 43  Surface anatomy of the stomach , liver & transverse colon pyloriation A located 11 on L1 L5 I Recall the mid-clavicular lines and the reference planes at L1 & L5. 44  Gross anatomy of the stomach The stomach is a hollow organ and composed of 4 parts: Cardia, Fundus, Body & the Pyloric part The pylorus leads to the duodenum. woode tube and - ten Anastomosis between Right & Left gastroepiploic arteries t Ensure spony- harf 45  Anatomy of the small intestine gases esophageal junction. Duodenum ( C- shaped with 4 parts) 1st : Superior part 2nd : Descending part 3rd : Horizontal part 4th : Ascending part 1st - 2nd 4th v 3rd connectoointestine of 7 large Clinical note: appendicitis ~ prevent backflow. cower part. right Anatomically, the small intestine is divided into the duodenum, jejunum & ileum. The jejunum and ileum is suspended by the intestinal mesentry. 46  Anatomy of the large intestine ↑ flexibility. Right colic Left colic (hepatic) flexure intraperitoneal (splenic) flexure Transverse colon Ascending colon Descending colon Cecum D Appendix Sigmoid colon Anal canal The arterial blood supply comes from the abdominal aorta and the venous blood drains via the portal venous system to the liver. 47  3-dimensional view of the large intestine Anterior view Posterior view Right lateral view Left lateral view (small intestine removed) (small intestine removed) Straight. Trace from the caecum stepwise to the anal canal. = rectum. An curve of 48  HSS 2011 Human Anatomy Regional Anatomy of the Abdomen & Pelvis 1.7 Anatomy of the Liver, Gall blabber, Pancreas & Spleen 49  Functional division of the Liver (I) The liver is a solid organ. An anterior view of the liver Line of demarcation Coronary ligament: inferior rena cava anchors the liver to the diaphragm f Anterior Medial Lateral segment V peritoneal fold segment segment two visceral peritoneal Falciform ligament - how falriform ligament formed ! Round ligament Gallbladder The left lobe consists of lateral segment & medial segment. The right lobe consists of anterior segment & posterior segment (see next plate). The caudate lobe is seen on the posterior aspect of the liver (see next plate). 50  3D-architecture of hepatic segments Explanation of nomenclature by Couinaud’s classification: Hepatic veins & IVC Counterclockwise individual segments Falciform ligament Portal triads 51  Hepatic segments (I – VIII) & porta hepatis Main lobar fissure (MLF) Medial Porta hepatis & the portal triads R segment L 1) Hepatic artery proper (red) V VI IV Lateral segment 2) Portal vein (blue) Anterior 3) Common hepatic duct (green) segment III Posterior segment I VII VIII II Caudate lobe (segment I): Visceral surface of liver (Inferoposterior view) on the left side of the IVC. Counterclockwise 52  Nomenclature of Hepatic Segments Liver Segment Numerical abbreviations Caudate lobe I Left lobe Lateral segment II, III Quadrate lobe Medial segment IVa, IVb look like square Right lobe Anterior segment V, VIII Posterior segment VI, VII 53  Anatomy of the pancreas tail head posterior to the Introperitoneal head of pancreas Head, neck, body & tail of pancreas SMV SMA - mesteric c/o USG Uncinate process of Head of pancreas artery Pancreas has mixed Endocrine & Exocrine functions. 54  Nomenclature of Hepatic Segments Liver Segment Numerical abbreviations Caudate lobe I Left lobe Lateral segment II, III Quadrate lobe Medial segment IVa, IVb Right lobe Anterior segment V, VIII Posterior segment VI, VII 55 Hepato-portal venous system Liver Portal vein Splenic vein SMV IMV “Everything absorbed from the GI tract” Venous return reaching the Liver for the 1st pass metabolism. 2nd metabolism kidney 56 pass. :  The pathway of bile secretion & transportation bile in liver hepativ cell : sevete the Right hepatic duct Left hepatic duct * bladder 1st = gall Superior 4th Cystic duct I Common hepatic duct Ascending 2nd Descending * Calot’s triangle 3rd Horizontal Common bile duct (CBD) Superior (1st) part Pancreatic duct Descending (2nd) part Horizontal (3rd) part The 2nd part of duodenum Ascending (4th) part 57  Surface anatomy of the Spleen 7th rib 8th rib 9th rib A major secondary lymphoid organ” 10th rib “The filter of the blood” At the left hypochondric region: 5 inches = 12-13 cm (long axis) 7 fluid ounces = 210 cm3 close to ribcage and diagmam 9th rib long axis along 10th rib 11th rib Spleen is intraperitoneal. Clinical method by percussion: Mid-clavicular line; Mid-axillary line Diaphragmatic surface of spleen 59  Anatomy of the spleen Spleen is a secondary lymphoid organ. S U P E R IOR Visceral surface Diaphragmatic surface Gastric = close to storal area Hilum S p le n ic v e in R e n al area S p le n ic a r ter y Splenic close to lym p h atic kidney ve s s e l I N F E R IO R Visceral surface splenic flexung “The filter of the blood”! 60  Anatomical relationship of the spleen A Transverse section of the abdomen viewed from below R L P Parietal peritoneum Visceral peritoneum Liver Stomach Gastrosplenic ligament Pancreas Gastric area Diaphragmatic surface Aorta Spleen Pancreatic area Renal area Kidneys Intraperitoneal organs: the liver, stomach and spleen Retroperitoneal organs: the duodenum, pancreas, abdominal aorta, IVC and the kidneys 61  Relationships between the gall bladder, duodenum & pancreas Anatomy of Pancreas 1. Celiac trunk A. Head B. Pancreatic duct C. Neck D. Body E. Tail 2nd part of duodenum 1 to neck) 2. Superior mesenteric artery 3. Inferior mesenteric artery 62  HSS2011 Human Anatomy Regional Anatomy of the Abdomen & Pelvis 1.8 Anatomy of the Kidneys & Ureters 63  Anatomy of the kidneys Kidney: 1) Retroperitoneal organs Posterior View 2) ~9 – 13 cm in length 3) At the vertebral level: T12 – L3. Spleen Left Kidney 64  Imaging anatomy of the ureters Coronal reconstruction of CT scan The ureters descend on the R with contrast L posterior abdominal wall to reach theurinary bladder. At the ureteropelvic junction relatively narrow Ureter crosses external iliac vessels at the pelvic brim Ureter traverses bladder wall CT = computed/ computerized tomography 65  Reference list Core Textbooks:  Saladin (2024) Human Anatomy, 5th edition. New York, N.Y: McGraw-Hill  Openstax Anatomy and Physiology Reference Textbooks:  Martini, Nath & Bartholomew (2017) Fundamentals of Anatomy & Physiology, 11th edition. Boston: Pearson  Drake, Vogl & Mitchell (2015) Gray’s Anatomy for Students, 3rd edition. Philadelphia: Churchill Livingstone Elsevier  Gosling et al (2017) Human Anatomy: Color Atlas & Textbook, 6th edition. Edinburgh: Elsevier  Moore, Agur & Dalley (2015) Essential Clinical Anatomy, 5th edition. Philadelphia :Wolters Kluwer Health 66