Anatomy Viva Important shit Flashcards
Heart
INTRO - Orientation
-2/3 on left, 1/3 on right. Roughly the size of a fist, sits between in mediastinum between lungs. Anteriorly is sternum, costal cartilages and medial rib ends of ribs 3-5. Pumps oxygenated blood around body and deoxygenated blood to the lungs. Made of cardiac muscle cells. 3 layers; epicardium, myocardium, endocardium.
Surfaces:
- Sternocostal (mostly RV)
- Right pulmonary (mostly RA)
- Left pulmonary (mostly LV, forms cardiac impression)
- Diaphragmatic (mostly LV and partly right)
Borders:
- Left (oblique, LV and slightly LA)
- Right (formed by RA, between IVC and SVC)
- Superior (RA, LV, auricles and emerging AA and PT)
- Inferior (formed mainly by LV)
Direction of blood flow, including chambers and valves
Innervated by:
cardiopulmonary splanchnic nerves T1-T6 (SNS)
Vagus (PSNS)
Coronary Arteries
INTRO - Orientation
-2/3 on left, 1/3 on right. Pumps oxygenated blood around body and deoxygenated blood to the lungs. Made of cardiac muscle cells. 3 layers; epicardium, myocardium, endocardium.
Blood supply to the muscle tissue of the heart.
Origin of coronary arteries: right and left sinuses of the right and left cusps of the aortic semilunar valves.
Right:
- Right sinus
- Runs in the coronary groove on the right side of the heart, giving off the SA nodal branch.
- Runs along the coronary groove giving off a right marginal branch - runs towards apex but doesnt reach it.
- Right coronary artery takes left hand turn around the posterior aspect of the heart.
- At the crux of the heart it gives off the AV nodal branch.
- After this point it gives off the terminal branch - posterior interventricular artery in the interventicular groove.
Left:
- Left sinus
- Emerges between left auricle and pulmonary trunk in the coronary groove.
- At the end of the groove it divides into 2 branches
- anterior interventricular branch (passes along interventricular groove to the apex of the heart, at inferior border it anastomoses with Posterior interventricular branch of the left coronary artery, can give off lateral/diagonal branch)
- circumflex branch
- Circumflex branch continues around to the posterior surface of the heart along the coronary groove where it gives off a left marginal branch (follows left margin of the heart and supplies the left ventricle.
- Circumflex then anatomises with Posterior interventricular artery (sometimes)
Right coronary artery:
Right atrium, right ventricle, SA node, AV node, part interventricular septum, part of left ventricle.
Left coronary artery: Left atrium Most of the left ventricle Can supply SA and AV Part of the interventricular septum
Coronary Veins:
Coronary sinus: main vein of the heart, right left to right along the posterior coronary groove.
Has no valve and runs straight into the Right atrium
Great cardiac vein: Runs with the anterior interventricular artery = drains into coronary sinus
Middle cardiac vein: Runs with the posterior interventricular artery, drains areas supplied by the right coronary artery.
Kidneys:
INTRO:
Size 10x5x2.5, approx 130 grams. Processes 1200ml of blood per minute. Retroperitoneal (posterior to parietal peritoneum) in the paravertebral gutters. Extend from level of T12 to L3, Left sits higher than the right because of the liver. The hilum sits at the level of the transpyloric plane which is at the level of L1.
Orientation: renal vein is always anterior, and the hilum is medial. Direction of the ureters is inferior.
The outer layer of the kidneys is the renal capsule which is smooth. Perinephric fat lies outside the renal capsule and aids in positioning of the kidney. Renal fascia surrounds the perinephric fat and extends as a dome over the superior pole and suprarenal gland. This fascia fuses at the lateral border but not the medial border.
Related structures: Superior: diaphragm Posterior: Lower ribs QL TA Psoas Iliohypogastric and ilioinguinal nerves Diaphragm Costodiaphragmatic recess of the pleura Anteriorly: LEFT: Stomach, spleen, pancreas, jejunum, descending colon RIGHT: Liver, duodenum, ascending colon
Renal a come out at the level of L1
Innervated by:
SNS - T10-T11
PSNS - Vagus nerve
Ureters
Intro: Two long narrow tubules with a thick muscular wall that convert urine from the kidneys to the bladder. 25 cm long, made up of outer longitudinal middle circular and inner longitudinal smooth muscle. They are lined with transitional epithelium.
Orientation: Renal vein, artery, ureter.
Pathway: Receives urine from the renal pelvis of the kidney
There are two parts to each ureter- abdominal and pelvic these parts are separated as it passes the SIJ.
- Passes down the anterior surface of psoas
- Crosses over the genitofemoral nerve
- crossed by gonadal vessels
- leaves psoas at the level of the bifurcation of the common iliac artery
- passes over the sacroiliac joint to enter the pelvis
- in males crossed by the vas deferens just before piercing the lateral horns of the bladder.
Innervation: SNS T10-L1
PNS: pelvic splanchnic S2-S4
Bladder
Intro: A hollow organ with strong muscular walls, made up of detruser muscle- outer longitudinal ,middle circular and inner longitudinal smooth muscle. They are lined with transitional epithelium.
When empty only located in the pelvic cavity and is tetrahedral in shape, when full can distend as high as umbilicus.
Orientation:
Surfaces and 4 angles:
1- Superior surface (Covered by peritoneum)
2- Inferior / lateral surfaces
1- Inferior/ posterior surface (1 cm is covered by peritoneum)
Angles:
-Apex: Superior surface and the inferior/lateral surface meet anteriorly. (points at pubic symph)
-Body: Between apex and fundus
-Base/fundus: Formed by the posterior wall and is convex
-Neck: Formed by the fundus/base and the inferior/lateral surfaces meet.
Pierced by the urethra and the internal urethral orifice.
Lateral horns: Where the superior, inferior/lateral surface, and posterior surface meet. Pierced by the ureters.
Trigone: is a triangular region at the base of the bladder lying between the two ureteral orifices and the internal urethral orifice. Smooth and relatively fixed.
Uvula: Projection of the trigone
Arterial supply: Superior vesicle
Innervation: PNS: s2,3,4
SNS: T11-L2
Male Urethra
Intro: Male urethra extends from the bladder neck to the tip of the penis, at the external urethral orifice for micturition. Most of the urethera is lined by transitional epithelium, in membranous in spongy it may change to pseudo stratified columnar. 20 cm in length and is a muscular wall tube made of smooth muscle.
It can be divided into 4 parts:
- Preprostatic urethra: Between the bladder and prostate, is surrounded by the internal uretheral sphincter.
- Prostatic urethra: Runs through the prostate received opening of ejaculatory duct. 2-4 cm
- Intermediate urthera (membranous): shortest section (1-2cm) begins at the apex of the prostate ends at the pulb of the penis. Surrounded by the external uretheral sphincter
Posterior laterally are the bulbourtheral gland. - Spongy Urethra- Below perineal membrane the urethra dilates to form bulbous urethra. It is the longest region (15cm) passes through the bulb and the corpus spongiosum of the penis. Starts at the intermediate part of the urthera and ends at the external urethral orifice. At the external urethral orifice it dilates and forms the navicular fossa - which is lined stratified squamous epithelium
Trachea and Bronchi
Intro: Trachea extends from the inferior end of larynx (C6) into the thorax where it divides into left and right bronchi at the sternal angle, T4/5 IVD. Is 10cm in length and 2.5 cm wide.
Is a hyaline cartilaginous tube, supported by incomplete cartilaginous rings that are open posteriorly. Posteriorly between the rings we find the smooth muscle, trachealis.
At the Transverse Thoracic plane the trachea divides into left and right primary/ main bronchi (right = shorter and wider, vertical directly into lung. Left= inferolateral, inferior to aortic arch and anterior to oesophagus and thoracic aorta,
(point to carina)
Which further divide into secondary/ lobar two on the left and three on the right.
-further divide into segmental/ tertiary approx 10 per side
Relations to trachea
Laterally:
Common carotid arteries, lobes of the thyroid gland.
Right: Brachiocephalic trunk
Anteriorly: Isthmus of the thyroid gland, Inferior thyroid veins
Posteriorly: Oesophagus
Arterial supply:
Two on the left:
- Left aspect of the descending thoracic aorta. Superior and inferior bronchial artery
-Right bronchial artery only 1, and has 3 options for exit.
1. Right aspect of TX aorta
2. Comes of a common branch with the superior left bronchial artery
3. 3rd Superior posterior intercostal artery
Nerve supply:
SNS: T1-T6
PNS Vagus
Lungs
Intro: Orientate them
Vital organ for respiration. The main site for gas exchange within the body and its primary function is to oxygenate blood. There are two lungs found in the thoracic cavity and are separated from each other by the heart and great vessels and other viscera in the mediastinum.
Surfaces 3:
- Costal surface
- Mediastinal surface
- Diaphragmatic
Borders 3:
- Anterior border: Costal + mediastinal ant
- Posterior border: Costal + mediastinal posteriorly
- Inferior: All three meet, circumscribes diaphragmatic
Apex: superior end convex in shape
Differences: Right lung: Heavier, shorter (due to diaphragm sitting higher-liver), wider (since the heart goes into left). Fissures: Separated into 3 lobes - Superior lobe Horizontal fissure -Middle Oblique fissure -Inferior
Mediastinal surface:
- Hilum (all together make up the root)
- Ant pulmonary veins
- pulmonary artery
- Bronchi Right
- Oesophagus groove
- Smaller cardiac impression
Left lung:
Lighter, shorter, thiner (due to cardiac notch)
Fissures- separated into two lobes
Superior and inferior divided by oblique
Mediastinal surface:
- Hilum (all together root)
- Superior-Inferior
- Pulmonary Artery
- Bronchi
- Pulmonary vein
- Groove for aortic arch
- Groove for the descending thoracic aorta
Peritoneum
Intro: Continuous transparent serous membrane that lines the abdominal and pelvic cavities and clothes/ invests viscera. It is the largest of serous membranes within the body.
Made up of two continuous layers:
- parietal layer: Lines the internal surface of the abdominal wall- gets its innervation from the part of the wall it lies on.
- visceral layer: Invests the viscera - gets its innervation from the organ it lies on.
Mesentry/ Peritoneal ligaments- When visceral peritoneum encloses or suspends organs within the peritoneal cavity.
-Permits blood vessels, lymph vessels, and nerves to reach the viscera.
Omentum: A fold of peritoneum that passes from the stomach and proximal part of the duodenum to the adjacent organs or abdominal wall.
Lesser Omentum:
-Connects the lesser curvature of the stomach and the proximal part of the duodenum to the liver.
Contains 2 ligaments:
1. Hepatoduodenal ligament - contains portal triad (hepatic artery, hepatic vein, and bile duct.
2. Gastrohepatic ligament
Greater Omentum: -4 layer fold of peritoneum that connects the greater curvature of the stomach to the transverse colon and its mesocolon "apron". Contains 3 ligaments: 1.Gastrophrenic ligament 2.Gastrosplenic ligament 3.Gastrocolonic ligament
Falciform ligament: attaches the liver to the anterior abdominal wall.
Omental foramen: The foramen from which the two sacs ( lesser peritoneal sac and the greater peritoneal sac) communicate with one another through an oval window.
Borders: Anterior: hepatoduodenal ligament and portal triad
Posterior: Inferior venacava
superior: cordate lobe of the liver
Inferior: proximal duodenum.
Arterial Supply to the abdomen
INTRO: There are three unpaired arteries of the abdominal aorta. There is also three paired branches. Three unpaired arteries which include: Celiac trunk (T12), Superior mesenteric artery (L1), and the inferior mesenteric artery (L3). The three paired arteries include: Suprarenal arteries (L1), renal arteries (L1), and the gonadal arteries at (L2).
Celiac trunk: Comes off the anterior aspect of the abdominal aorta. Has 3 branches:
- Splenic artery:
- Short gastric artery (fundus of the stomach)
- Pancreas arteries (pancreas 8-10)
- Left gastroomental artery (Left greater curvature of the stomach)
- Splenic artery (spleen) - Left gastric artery (left lesser curvature of the stomach)
- Common hepatic artery
1. Right Gastric artery ( Right lesser curvature of the stomach.
2. Gastroduodenal (stomach and duodenum) 3 branches:
1. Anterior posterior Superior
pancreaticoduodenal arteries (pancreas and duodenum)
2. supraduodenal artery (superior duodenal
3. Right gastroomental artery (Right greater curvature of the stomach. - Hepatic proper:
2: 1. Left hepatic (liver)
2. Right hepatic (liver)
-cystic (bile duct)
Superior Mesenteric Artery:
5 branches:
1.Anterior and posterior inferior pancreaticodunodenal artery- inferior aspect of the pancreas and duodenum
2. Intestinal arteries (intestines -18)
3. Ileocolic- Ileum, ascending colon
-appendicular branch to appendix
4. Right Colic (ascending colon)
5. Middle colic (transverse colon)
Inferior mesenteric artery 3 branches
- Left colic artery (descending colon)
- sigmoid artery (sigmoid colon)
- Superior rectal ( proximal part of rectum)
Spleen
Intro: A large, soft, highly vascular lymphoid organ made up of red and white pulp. It is largest of the lymphoid organs and roughly the size of fist. Main function : defence, production of WBC, platelet storage and red blood cell storage.
It is found deep to ribs 9-11 on the left in the mid axillary line. It is separated from the ribs by the diaphragm. Completely covered in visceral peritoneum except hilum.
Surfaces: Visceral : Has impressions from 4 organs Anterior aspect: Stomach Inferior aspect: left colic flexure Medial aspect: Left kidney Hilum: Tail of the pancreas
Diaphragmatic : the convexity of the spleen lies against the diaphragm
Ligaments of the spleen 2:
- Gastrosplenic (stomach to spleen)
- Splenorenal (spleen to kidney)
Arterial supply:
Splenic artery-branch of the celiac trunk
Nerve supply: Sympathetic T6-10
Parasympathetic: vagus
Cranial Nerves 12 pairs
There are 12 pairs of cranial nerves. They have 5 different types of fibres: 1 Somatic afferent 2 Somatic efferent 3 Visceral afferent 4 Visceral efferent 5 Special sensory
Visceral efferent means parasympathetic: there are 4 cranial nerves 3, 7, 9, and 10
- Olfactory - Smell
- Optic- Sight (largest CN)
- Oculomotor- Eye movement (Parasympathetic)
- Trochlear- Superior oblique ( Longest intracranial pathway but also the smallest )
- Trigeminal- 3 branches Opthlamic, maxillary and mandibular innervates skin on the face and muscles of mastication (second largest)
- Abducens- Lateral rectus
- Facial - Muscles of facial expression (longest interosseous pathway)
- Vestobilocochlear - hearing and balance ( nerves that doesnt leave the skull)
- Glossopharyngeal - Taste, swallowing and cutaneous sensation to outside of ear + PNS
- Vagus- Longest nerve distribution pathway Innervates numerous things.
- Accessory- Innervates traps (it runs with a spinal nerve)
- Hypoglossal- Tongue
Male pelvic Organ and perineum
Intro: This is a cross section of the male perineum. The male perineum includes: anal canal, intermediate and spongy parts of the urethra, the root of the penis and the scrotum.
Penis: Male sexual organ and common outlet for urine and semen. The penis has three parts Root, body and glans. The root is fixed and the body hangs freely.
- Root has 4 parts
- Crura, the bulb, ischiocavernosus, and bulbospongiosus muscle
- Crura and bulb = erectile tissue
- Crura = legs of corpora cavernosa
- Bulb= Corpus spongiosum
- Body: Purely erectile tissue. It contains skin, connective tissue, lymph and blood vessels. Corpora cavernosa and corpus spongiosum which has the urethra running through it. Enclosed in a fibrous capsule- Tunica Albuginea + fascia.
- Glans- The distal region of the corpus spongiosum which expands to form the glans penis. The head of the penis. The margins of the penis where it projects beyond the end of corpora cavernosa = corona. Near the tip we have the navicular fossa which is a dilation of the spongy urethera and the external orifice (meatus)
Arterial supply: Internal pudendal
Nerve: Pudendal S2-4
Scrotum
Scrotum: A cutaneous fibromuscular sac made up of skeletal and smooth muscle that aid in temperature maintenance by contracting the testes. It is an outpouching of the lower part of the anterior abdominal wall. The left testis sits lower than the right to assist with movement. Main function: Spermatogenesis therefore sits 1.2 degrees lower than core temperature.
Contains:
- Testes - Epididymus - Distal ends of the spermatic cord
Arterial supply: External and internal pudendal
Nerve supply: Ilioinguinal, genitofemoral + posterior scrotal nerves.
