High Yield Flashcards

Question

COW variants only

Answer 1

COW is an anastomotic arterial polygon residing at the level of the suprasellar cistern around the optic chiasm and infundibular stalk of the pituitary gland which links the anterior and posterior cerebral circulations (ICA, vertebral arteries) formed by the paired terminal internal carotid arteries, A1 segments of ACA, ACOM, PCOMs, P1 of PCAs and basilar tip basilar artery divides at the upper border of pons to the PCA PCOM arises at the anterior perforate substance from each ICA and runs back through the interpeduncular cistern to join the ipsilateral PCA multiple variants arise from this polygon and only 25% of population have the "normal" configuration ``` Variants ACA: - single ACA - hypoplastic unilateral or bilateral ACA - azygos ACA ``` ACOM: - absent ACOM - fenestrated ACOM PCOM: - fetal PCOM - absent unilateral or bilateral PCA: - hypoplastic single or bilateral - absent unilateral or bilateral ``` Persistent carotid-vertebrobasilar anastomoses communication: - persistent trigeminal artery persistent otic artery persistent hypoglossal artery persistent proatlantal artery ```

Answer 2

the spinal cord is supplied by multiple vertical arteries which are reinforced by marginal arteries at varying levels Anterior spinal artery - single artery formed by the union of the vertebral arteries at the level of foramen magnum - runs in the anterior spinal groove - supplied anterior 2/3 of the spinal cord posterior spinal arteries - paired spinal arteries in the right and left posterior spinal grooves - arise either from vertebral arteries or PICAs - supply posterior 1/3 of spinal cord anterior and posterior spinal arteries communicate by the arterial vasocorona which encircles the cord inferiorly the anterior and posterior spinal arteries form the cruciate anastomosis of the conus medullaris entire spinal cord reinforced by numerous radicular arteries radicular arteries: - arises from PICA, vertebral arteries, cervical arteries, posterior intercostal arteries, lumbar arteries, lateral sacral arteries - pass through the intervertebral foramina and divide into anterior and posterior radicular arteries and have variable anastomosis with the spinal arteries Great artery of Adamkiewicz - largest radicular artery - left sided - T9-12 posterior intercostal branch - travels posteriorly and ascends on the mid sagittal anterior surface of the spinal cord.makes a characteristic U turn before merging with the anterior spinal artery Variants - variable origin of the anterior spinal artery, V3 or V4 segment - posterior spinal artery can be absent or hypoplastic unilateral or bilateral - posterior spinal artery can arise from the PICA or vertebral arteries - varying levels of the great artery of Adamkiewicz (lumbar arterial contribution) - right sided artery of Adamkiewicz

Answer 3

Coronary arteries provide oxygenated blood to the myocardium of the heart originate just superior to the aortic semilunar cusps at the right and left coronary sinus 2 main trunks: right coronary artery and left main coronary artery right coronary artery runs through the right atrioventricular groove posteriorly and descends as the posterior descending artery before turning anteriorly at the crux of the heart in a right dominant circulation the left main coronary artery has a short trunk before bifurcating into the left circumflex and left anterior descending artery left circumflex travels within the left atrioventricular groove and may continue as the posterior descending artery in a left dominant circulation left anterior descending travels within the interventricular groove ``` supply: RCA - sinoatrial node - atrio-ventricular node - right atrium, right ventricle - posterior inferior aspect of the heart in right dominant - inferior interventricular - acute marginal ``` LCx - left atrium, left ventricle, posterior inferior aspect of heart in left dominant - obtuse marginal LAD - interventricular septum - left ventricle - diagonal and septal branches venous drainage - variable - great, middle and small cardiac veins - posterior vein of the left ventricle - vein of Marshall - anterior cardiac veins - all drain into the venous coronary sinus at the right atrium - thebesian veins drain directly into the right atrium Variants - absent: LCx, LAD, RCA - hypoplastic: LCx, LAD, RCA - ramus intermedius - anomalous location of coronary ostia (sinotubular junction or ascending aorta) - anomalous left coronary artery off pulmonary artery - single coronary artery - split artery origin

Answer 4

elbow joint is a complex hinge- pivot joint formed by the articulation of the distal humerus with the proximal radius and ulna - synovial joint with a joint capsule - hyaline lined articular surfaces - 3 articulations: radiohumeral, ulnahumeral, radioulna - radius articulates with the capitelleum of the humerus - ulna articulates with the trochlea of the humerus - in full elbow flexion the coronoid process of the ulna sits within the coronoid fossa of the humerus - in full extension the olecranon process of the ulna sits within the olecranon fossa of the humerus - radial head with radial notch of ulna - strengthened by medial and lateral collateral ligaments Movements - elbow flexion and extension - supination - pronation Fat pads - coronoid fossa, radial fossa, olecranon fossa Bursae - superficial olecranon bursa, subtendinous, intratendinous olecranon bursa, bicipitoradial bursa Relations anterior: biceps brachii, brachialis, median nerve, brachial artery posterior: olecranon bursa, triceps tendon lateral: common extensor tendon, supinator medially: ulna nerve ``` Ligaments - medial collateral ligaments * anterior bundle > medial epicondyle to the sublime tubercle * posterior bundle > medial epicondyle to medial olecranon * oblique bundle > thickening between the anterior and posterior bundles inferiorly ``` - lateral collateral ligaments * lateral ulna collateral ligament >lateral epicondyle to supinator crest * lateral radial collateral ligament > lateral epicondyle to annular ligament and supinator muscle fascia *annular ligament > sigmoid notch to supinator crest around head of radius blood supply: - elbow anastomosis, branches from the brachial artery, radial and ulna artery venous drainage - brachial veins - cephalic and basilic veins innervation: branches of the brachial plexus, median nerve, ulna nerve, radial nerve, musculocutaenous nerves

Answer 5

inguinal ligament is formed by the thickening of the external oblique aponeurosis. important landmark for pelvic structures transiting to the lower limbs - ASIS to pubic tubercle - forms part of the inguinal canal (anterior and superior walls) - some fibres pass posterior and insert on superior pubic ramus to form the lacunar ligament - fibres runs with lacunar continue to pass more lateral and insert into the pecten pubis to form the pectineal ligament - superior fibres past the tubercle and fuse with contralateral external oblique aponeurosis to form the reflected inguinal ligament - upper surface: medial give origin to external spermatic fascia lateral 2/3 to internal oblique muscle lateral 1/3 to transversus abdomnis muscle continuous with fascia lata of thigh Relations anterior: subcutaenous tissues, skin posterior: femoral nerve, femoral artery, vein, external iliac vein, iliopsoas muscle, inguinal lymph nodes medial: pubic symphysis

Answer 6

SMA - arterial supply of the mid gut - one of the major unpaired visceral arteries of the abdominal cavity - arises from the anterior aspect of the abdominal aorta just under the celiac trunk L1 - runs to the left of the superior mesenteric vein behind the neck of the pancreas but anterior to unicate process of the pancreas and D3 - divides into right and left branches - left branch: inferior anterior and posterior pancreaticoduodenal arteries, jejunal and ileal arteries - right branch: ileocolic artery, right colic, middle colic arteries - terminates at the ileocolic artery anastomoses: - arc of buhler - celiac trunk via pancreaticoduodenal arteries, pancretica arteria magna - arc of drummond - arc of riolan Variants - replaced right hepatic artery - accessory right hepatic artery - replaced common hepatic artery - replaced splenic artery - replaced left gastric artery

Answer 7

- one of the three unpaired visceral branches of the abdominal aorta - hindgut supply - emerges below the gonadal and renal arteries - left of midline at L3 - obliquely downwards towards pelvic brim - anterior then to left aorta branches - left colic artery - 2-4 sigmoid arteries - superior rectal artery supply: - splenic flexure to upper two third of the rectum relations: anterior: d3 posterior: abdominal aorta, left psoas, sympathetic trunk left: inferior mesenteric vein Variants - duplicated IMA - absent - absent left colic branch - arc of Riolan * *rectum - superior rectal: IMA - middle rectal: internal iliac artery - inferior rectal: internal pudendal artery

Answer 8

aortic arch formed by the left 4th arch vessel - left side of body - connects the ascending aorta to the descending aorta - ascends in the superior mediastinum to the level of the sternal notch before arch posteriorly and descending in the left hemithorax - normally 3 main branches: left common carotid, left subclavian artery, brachiocephalic trunk - T4/5 plane Variants Structural: - hypoplastic ascending aorta - interrupted aortic arch - cervical aortic arch - circumflex aorta - right sided aortic arch - coarctation of the aortic - duplicated aortic arch - patent ductus arteriosus branches: - thyroidea ima - true bovine arch: single trunk for left and right carotid arteries and subclavian arteries - 2 brachiocephalic trunks - 4 vessels arising independently from the aortic arch - vertebral arteries arising form the arch - aberrant right or left subclavian artery

Answer 9

superficial and deep upper limb venous drainage of the left upper limb to the heart Superficial - cephalic vein > continuation of the radial aspect of the superficial palmar veins > travels superficial to the deep fascia of the forearm, subcutaneous course >anterolateral course over the biceps brachi muscle in the arm in the deltopectoral groove > dives through the clavicopectoral fascia and insert into the 1st part of the axillary vein - basilic vein > continuation of the ulna side of the dorsal venous network > ascends posteromedially in the forearm > passes anterior to medial epicondyle of humerus > continues up the anteromedial aspect of arm and joins the brachial vein after piercing the brachial fascia at the basilic hiatus (halfway between elbow and axilla) - median cubital vein > connects the cephalic and basilic veins - median antebrachial vein - palmar venous plexus drain into basilic or median cubital veins Deep venous Brachial vein - formed by the radial and ulna veins - paired venous channels acommpanying the radial and ulnar arteries - runs alongside the brachial artery in the arm - joined by the basilic vein - continues as the axillary vein at inferior border of teres major muscle axillary vein becomes the subclavian vein at the lateral border of the 1st rib joins with the internal jugular vein to become the brachiocephalic vein joins with the opposite brachiocephalic vein to form the superior vena cava superior vena cava joins into the right atrium

Answer 10

hollow, thick walled muscular organ of the female reproductive tract within the lesser pelvis - inverted pear shape - body and cevix - halfway between the apex and base is a slight constriction known as the isthmus - above is body, below is cervix - body which lies above the plane passing through bilteral uterine tube orifices is known as the fundus - inverted triangular cavity, base formed by the internal surface of the fundus, apex where the cavity communicates with the cervical canal Musculotendinous - pubocervical ligament - transverse cervical ligament - uterosacral ligament - puborectalis, pubovaginalis relations anterior: bladder, utero-vesical pouch posterior: rectum, pouch of douglas lateral: broad ligament, uterine vessels and tubes inferior: cervix and vagina blood supply: arterial: uterine, ovarian arteries, anastomotic trunk venous: internal iliac vein lymphatics: - fundus to paraaortic lymph nodes - body and cervix to internal and external iliac nodes to superficial inguinal nodes innervaton - hypogastric and ovarian plexi - S3-4 ``` variants bifid uterus absent uterus unicornuate uterus arcuate uterus septate uterus ```

Answer 11

muscular tube that convey food and fluids from the pharynx to the stomach. 3 main anatomical constrictions: - cricoid cartilage - aortic arch - oesophageal hiatus divided into cervical, thoracic and abdominal oesophagus. Cervical: - continuous with the hypopharynx - upper oesophageal sphincter (cricopharyngeus) - upper oesophageal sphincter formed by cricopharyngeus - descends left of the midline in the neck Thoracic: - superior thoracic aperture (T1) to oesophageal hiatus (T10) - midline at T5 before continuing on left side of posterior mediastinum Abdominal: - oesophageal hiatus to the cardia of the stomach - lower oesophageal sphincter A and B rings Relations posterior: vertebral column, thoracic duct, accessory hemiazygos, hemiazygos anterior: trachea, recurrent laryngeal nerves, left main bronchus, left atrium left: left lung and pleura right: lung and pleura arterial upper third: inferior thyroid middle third: thoracic aorta lower third: left gastric venous: upper third: inferior thyroid middle third: azygos lower third: left gastric vein lymphatic drainage upper third: deep cervical middle third: posterior mediastinal lower third: celiac innervation sympathetic vagal variants oesophageal bronchus oesophageal atresia aberrant right subclavian passing anterior or posterior to oesophagus

Answer 12

breasts are paired apocrine glands used in milk production post partum in females lymphatic drainage of the breast is important in understanding and predicting the flow in the setting of breast cancer screening or management 3 main pathways for lymphatic drainage: 1. axillary pathway (75%) - subareolar plexus and satellite lymphatics - inferior edge of pectoralis major to reach the pectoral group of axillary lymph nodes 2. internal mammary pathway - both medial and lateral halves of breast and passes through pect major - connections may lead across the median plane to the contralateral breast 3. retromammary pathway - posterior portion of the breast lymphatics may reach the rectus sheath, subperitoneal and subhepatic plexi