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Score — click each question to reveal the answer
Q1
Which of the following correctly lists the three branches of the aortic arch from right to left?
Unit 11 Slides · Gray's 4e Ch3
Unit 11 Slides · Gray's 4e Ch3
A. Brachiocephalic trunk → left common carotid → left subclavian
B. Left subclavian → left common carotid → brachiocephalic trunk
C. Right common carotid → right subclavian → left subclavian
D. Brachiocephalic trunk → left subclavian → left common carotid
✓ Answer: A — Brachiocephalic trunk → left common carotid → left subclavian
The aortic arch gives off three branches (right to left): (1) Brachiocephalic (innominate) trunk — which then divides into the right subclavian and right common carotid; (2) Left common carotid artery; (3) Left subclavian artery. The left side arteries arise directly from the arch; the right-sided arteries arise via the brachiocephalic trunk.
⚠ D reverses the order of the 2nd and 3rd branches. C is wrong because the right common carotid and right subclavian arise from the brachiocephalic trunk, not directly from the arch.
Q2
Which of the following is the ONLY branch(es) given off by the ascending aorta?
Unit 11 Slides · Gray's 4e Ch3
Unit 11 Slides · Gray's 4e Ch3
A. Brachiocephalic trunk and left common carotid
B. Right and left coronary arteries
C. Posterior intercostal arteries and bronchial arteries
D. Phrenic arteries and coeliac trunk
✓ Answer: B — Right and left coronary arteries only
The ascending aorta gives off only the right and left coronary arteries, which arise from the aortic sinuses (of Valsalva) just above the aortic valve. No other branches arise from the ascending portion. The aortic arch gives the three head/neck/arm vessels; the descending thoracic aorta gives intercostal and bronchial arteries; the abdominal aorta gives the visceral and parietal branches.
⚠ A = branches of the aortic arch. C = branches of the descending thoracic aorta. D = branches of the abdominal aorta. Only B correctly identifies the ascending aorta's exclusive branches.
Q3
The left anterior descending (LAD) artery — known as the “widow maker” — primarily supplies:
Unit 11 Slides · Gray's 4e Ch3
Unit 11 Slides · Gray's 4e Ch3
A. Posterior interventricular septum and inferior left ventricle
B. SA node and right atrium
C. Anterior interventricular septum and anterior wall of left ventricle
D. Posterior left ventricle and AV node
✓ Answer: C — Anterior IVS + anterior wall of left ventricle
The LAD artery is a branch of the left coronary artery (LCA). It runs in the anterior interventricular groove and supplies: (1) the anterior 2/3 of the interventricular septum (via septal perforators); (2) the anterior wall of the left ventricle; (3) the apex of the heart. It is called the “widow maker” because occlusion causes a large anterior MI which may be immediately fatal.
⚠ A = territory of the posterior descending artery (from RCA in right-dominant circulation). B = SA node is supplied by the RCA (~60%) or LCA. D = posterior LV + AV node = RCA territory. LAD = anterior; RCA = inferior/posterior.
Q4
The coeliac trunk arises from the abdominal aorta at vertebral level T12 and gives off three branches. Which set is CORRECT?
Unit 11 Slides · Gray's 4e Ch4
Unit 11 Slides · Gray's 4e Ch4
A. Left gastric, right gastric, splenic
B. Common hepatic, gastroduodenal, splenic
C. Superior mesenteric, left gastric, splenic
D. Left gastric, splenic, common hepatic
✓ Answer: D — Left gastric, splenic, common hepatic
The coeliac trunk (T12) is the first unpaired visceral branch of the abdominal aorta. Its three direct branches are: (1) Left gastric artery (smallest; supplies lesser curvature + lower oesophagus); (2) Splenic artery (largest; tortuous; supplies spleen, short gastric arteries, left gastroepiploic, pancreatic branches); (3) Common hepatic artery (gives hepatic artery proper + gastroduodenal). Mnemonic: LSC = Left gastric, Splenic, Common hepatic.
⚠ Right gastric (B) arises from hepatic artery proper, not from the trunk directly. Gastroduodenal (C) is a branch of common hepatic. SMA (D) is a separate branch of the abdominal aorta at L1, not from the coeliac trunk.
Q5
The superior mesenteric artery (SMA) arises at L1 and supplies the midgut. Which segment of bowel marks the DISTAL limit of SMA supply?
Unit 11 Slides · Gray's 4e Ch4
Unit 11 Slides · Gray's 4e Ch4
A. Junction of mid and left-third of the transverse colon (splenic flexure area)
B. Ileocaecal junction
C. Hepatic (right colic) flexure
D. Proximal descending colon
✓ Answer: A — Mid-transverse colon (splenic flexure area)
The SMA (L1) supplies the midgut: from the duodenojejunal (DJ) flexure to the junction of the mid- and left-third of the transverse colon (approximately at the splenic flexure). Branches: inferior pancreaticoduodenal, jejunal, ileal, ileocolic, right colic, middle colic. The SMA/IMA watershed is at the splenic flexure — the most vulnerable site for ischaemic colitis.
⚠ A (ileocaecal junction) is within SMA territory, not the distal limit. B (hepatic flexure) is well within SMA territory. D (descending colon) is IMA territory. The correct answer is C: SMA reaches to the mid-transverse colon.
Q6
The inferior mesenteric artery (IMA) arises at L3. Which of the following correctly describes its territory?
Unit 11 Slides · Gray's 4e Ch4
Unit 11 Slides · Gray's 4e Ch4
A. Entire transverse colon through to the anal canal
B. Descending colon, sigmoid colon, and upper rectum (hindgut)
C. Right colon and terminal ileum only
D. Sigmoid colon, rectum, and anal canal (entire)
✓ Answer: B — Descending colon, sigmoid, upper rectum (hindgut)
The IMA (L3) supplies the hindgut: from the mid-transverse colon (splenic flexure) to the upper two-thirds of the rectum. Branches: left colic artery (descending colon), sigmoid arteries (2–4), superior rectal artery (terminal branch; supplies upper rectum). The middle and lower rectum are supplied by the middle and inferior rectal arteries from the internal iliac — not the IMA.
⚠ B is too wide (transverse colon is partly SMA). C is SMA territory. D extends too far — the IMA terminates as the superior rectal artery; middle and inferior rectal arteries come from the internal iliac system.
Q7
Which two vessels form the communicating links that complete the Circle of Willis?
Unit 11 Slides · Gray's 4e Ch8
Unit 11 Slides · Gray's 4e Ch8
A. Anterior cerebral and posterior cerebral arteries
B. Middle cerebral and basilar arteries
C. Anterior communicating and posterior communicating arteries
D. Anterior communicating and middle cerebral arteries
✓ Answer: C — Anterior communicating + posterior communicating arteries
The Circle of Willis is formed by the junction of the internal carotid system (anterior) and the vertebrobasilar system (posterior). The two communicating arteries complete the circle: (1) Anterior communicating artery — joins the two anterior cerebral arteries (ACA) across the midline; (2) Posterior communicating arteries (paired) — each joins an internal carotid artery to the corresponding posterior cerebral artery. These allow collateral flow if one vessel is occluded.
⚠ The anterior and posterior cerebral arteries (A) are the main named vessels that form the ring, not the communicating vessels. The communicating arteries are the short bridges that complete the circle. C = neither is a communicating artery.
Q8
The middle meningeal artery enters the skull through which foramen, and rupture of this artery causes what complication?
Unit 11 Slides · 2022 Review · Gray's 4e Ch8
Unit 11 Slides · 2022 Review · Gray's 4e Ch8
A. Foramen ovale; subdural haematoma
B. Foramen lacerum; subarachnoid haemorrhage
C. Foramen rotundum; extradural haematoma
D. Foramen spinosum; extradural (epidural) haematoma
✓ Answer: D — Foramen spinosum; extradural haematoma
The middle meningeal artery is a branch of the maxillary artery (from the external carotid system). It enters the middle cranial fossa through the foramen spinosum and runs in a groove on the inner surface of the temporal bone (pterion region). A blow to the temple that fractures the thin pterion can rupture this artery → extradural (epidural) haematoma — blood accumulates between the skull and the dura, with a classic lucid interval followed by rapid neurological deterioration (uncal herniation).
⚠ Subdural haematoma is from bridging veins (not an artery). Foramen ovale = mandibular nerve (V3) + accessory meningeal artery. Foramen lacerum = ICA. Foramen rotundum = maxillary nerve (V2). Only foramen spinosum carries the middle meningeal artery.
Q9
At which anatomical landmark does the subclavian artery become the axillary artery?
Unit 11 Slides · Gray's 4e Ch6
Unit 11 Slides · Gray's 4e Ch6
A. Lateral border of the first rib
B. Lateral border of the clavicle
C. Inferior border of teres major
D. Medial border of the first rib
✓ Answer: A — Lateral border of the first rib
The arterial chain of the upper limb: subclavian → axillary → brachial → radial + ulnar. The subclavian artery becomes the axillary artery at the lateral border of the first rib. The axillary artery then becomes the brachial artery at the lower border of teres major. The brachial artery divides into radial and ulnar at the cubital fossa (opposite the neck of the radius).
⚠ C (lateral border of teres major) is where the axillary becomes brachial — not where subclavian becomes axillary. D (medial border of the 1st rib) is where the subclavian originates as it leaves the thorax, not where it becomes axillary. The transition point is the lateral border of the 1st rib.
Q10
At which level does the brachial artery bifurcate into the radial and ulnar arteries?
Unit 11 Slides · Gray's 4e Ch6
Unit 11 Slides · Gray's 4e Ch6
A. Opposite the medial epicondyle of the humerus
B. Opposite the neck of the radius in the cubital fossa
C. At the lower border of teres major
D. At the midpoint of the antecubital fossa, opposite the lateral epicondyle
✓ Answer: B — Opposite the neck of the radius in the cubital fossa
The brachial artery terminates in the antecubital fossa (cubital fossa) by dividing into the radial artery (lateral) and ulnar artery (medial) opposite the neck of the radius. The radial artery descends laterally in the forearm to the wrist; the ulnar artery descends medially. Both contribute to the palmar arches in the hand. Clinically: the brachial artery is the site for blood pressure measurement and brachial artery catheterisation.
⚠ C = lower border of teres major is where axillary becomes brachial. A = the medial epicondyle is where the brachial artery passes (in the medial bicipital groove) but it does not bifurcate there. The bifurcation is in the cubital fossa opposite the radial neck.
Q11
Where is the radial pulse palpated at the wrist, and what tendon is its lateral landmark?
Unit 11 Slides · Gray's 4e Ch6
Unit 11 Slides · Gray's 4e Ch6
A. Lateral to palmaris longus, just proximal to the carpal tunnel
B. Medial to flexor carpi ulnaris at the ulnar side of the wrist
C. Lateral to flexor carpi radialis (FCR), on the anterior surface of the distal radius
D. In the anatomical snuffbox, lateral to extensor pollicis longus
✓ Answer: C — Lateral to flexor carpi radialis at the wrist
The radial pulse is palpated at the wrist on the anterior (flexor) surface of the distal radius, lateral to the tendon of flexor carpi radialis (FCR). This is the standard clinical site for pulse assessment. The radial artery can also be felt in the anatomical snuffbox (between abductor pollicis longus/extensor pollicis brevis laterally and extensor pollicis longus medially) — important in scaphoid fracture assessment and Allen's test before radial artery cannulation.
⚠ C describes the ulnar pulse (lateral to flexor carpi ulnaris). D is also a correct secondary site but the primary clinical site is the wrist lateral to FCR (B). A (lateral to palmaris longus) is imprecise — FCR is the specific named landmark.
Q12
Regarding the femoral artery in the femoral triangle, which arrangement (lateral to medial) correctly describes the neurovascular contents at the inguinal ligament?
Unit 11 Slides · 2022 Review · Gray's 4e Ch5
Unit 11 Slides · 2022 Review · Gray's 4e Ch5
A. Nerve → Artery → Vein → empty space (lymphatics) — NAVY
B. Vein → Artery → Nerve → lymphatics
C. Artery → Vein → Nerve → lymphatics
D. Nerve → Vein → Artery → lymphatics
✓ Answer: A — NAVY: Nerve, Artery, Vein, Y (empty/lymphatics)
Under the inguinal ligament, from lateral to medial: Nerve (femoral nerve, lateral) → Artery (femoral artery) → Vein (femoral vein) → Y (femoral canal / lymphatics, medial). Mnemonic: NAVY. The femoral canal contains lymphatics and fat; it is the site of a femoral hernia (medial to the femoral vein). The femoral artery is the landmark: the femoral pulse is palpated at the midpoint of the inguinal ligament (midinguinal point).
⚠ B, C, D all misplace the nerve and vessels. The key fact: nerve is most lateral; vein is medial to artery; femoral canal (Y) is most medial. Femoral hernia neck: medial to the femoral vein, which explains why femoral hernias are more common in women (wider pelvis → wider femoral canal).
Q13
The popliteal artery divides into which two terminal branches, and at what level?
Unit 11 Slides · Gray's 4e Ch5
Unit 11 Slides · Gray's 4e Ch5
A. Anterior tibial + posterior tibial arteries, at the lower border of popliteus
B. Anterior tibial + fibular (peroneal) artery, at the lower border of popliteus
C. Posterior tibial + fibular artery, in the posterior compartment of the leg
D. Dorsalis pedis + posterior tibial arteries, at the ankle
✓ Answer: A — Anterior tibial + posterior tibial, at the lower border of popliteus
The popliteal artery (continuation of femoral in the popliteal fossa) divides into the anterior tibial artery and the posterior tibial artery at the lower border of the popliteus muscle. The anterior tibial artery then passes forward through an opening in the interosseous membrane into the anterior compartment of the leg, eventually becoming the dorsalis pedis at the ankle. The posterior tibial descends in the posterior compartment and gives off the fibular (peroneal) artery shortly after its origin.
⚠ A and C are wrong: the fibular (peroneal) artery is not a direct branch of the popliteal; it arises from the posterior tibial. D is wrong: dorsalis pedis is the continuation of anterior tibial at the ankle, not a direct branch of popliteal.
Q14
The dorsalis pedis artery is the continuation of which vessel, and where is its pulse palpated?
Unit 11 Slides · Gray's 4e Ch5
Unit 11 Slides · Gray's 4e Ch5
A. Posterior tibial artery; behind the medial malleolus
B. Anterior tibial artery; on the dorsum of the foot lateral to extensor hallucis longus
C. Fibular (peroneal) artery; lateral to extensor hallucis longus
D. Popliteal artery; over the navicular bone
✓ Answer: B — Continuation of anterior tibial; dorsum of foot lateral to EHL
The dorsalis pedis artery is the direct continuation of the anterior tibial artery as it crosses the ankle onto the dorsum of the foot. The pulse is palpated on the dorsum of the foot, lateral to the tendon of extensor hallucis longus (EHL), over the navicular/cuneiform bones. It is one of the key peripheral pulses assessed in peripheral arterial disease (PAD) and in patients with diabetes (high risk of foot ischaemia).
⚠ A = posterior tibial pulse is behind the medial malleolus. B = fibular (peroneal) artery runs deep in the lateral compartment and does not have a named surface pulse. D = popliteal is in the popliteal fossa. Dorsalis pedis = anterior tibial continuation, dorsum of foot.
Q15
The fibular (peroneal) artery is a branch of which vessel, and in which compartment of the leg does it run?
Unit 11 Slides · Gray's 4e Ch5
Unit 11 Slides · Gray's 4e Ch5
A. Anterior tibial; anterior compartment
B. Popliteal; lateral compartment
C. Posterior tibial; posterior compartment (deep)
D. Femoral; posterior compartment
✓ Answer: C — Branch of posterior tibial; posterior compartment
The fibular (peroneal) artery is a major branch of the posterior tibial artery, given off shortly after the posterior tibial arises from the popliteal. It runs in the posterior (deep) compartment of the leg, along the medial aspect of the fibula. It supplies the lateral compartment muscles (peronei/fibulares) via perforating branches, and the posterior compartment directly. It terminates by giving calcaneal branches to the lateral side of the heel.
⚠ A is wrong: anterior tibial is in the anterior compartment and gives no fibular branch. C is wrong: peroneal artery is NOT a direct popliteal branch. D is wrong: femoral artery ends at the adductor hiatus. The posterior tibial is the parent of the fibular artery.
Q16
The external carotid artery (ECA) gives off eight named branches. Using the mnemonic SALFOPMS, which of the following is NOT a direct branch of the ECA?
Unit 11 Slides · Gray's 4e Ch8
Unit 11 Slides · Gray's 4e Ch8
A. Superior thyroid artery
B. Maxillary artery
C. Occipital artery
D. Ophthalmic artery
✓ Answer: D — Ophthalmic artery (branch of ICA, NOT ECA)
The ECA branches (mnemonic SALFOPMS): Superior thyroid, Ascending pharyngeal, Lingual, Facial, Occipital, Posterior auricular, Maxillary, Superficial temporal. The ophthalmic artery is a branch of the internal carotid artery (ICA), given off after the ICA enters the cranial cavity. It supplies the eye (central artery of the retina, an end artery) and orbit. ECA = external face/scalp/neck; ICA = brain + eye.
⚠ A (superior thyroid), C (maxillary), and D (occipital) are all direct ECA branches listed in SALFOPMS. The ophthalmic artery (B) is the first intracranial branch of the ICA — its occlusion causes sudden monocular blindness.
Q17
The vertebral artery is a branch of the subclavian artery. It enters the transverse foramina at which cervical vertebra, and what does it join to form after entering the skull?
Unit 11 Slides · Gray's 4e Ch8
Unit 11 Slides · Gray's 4e Ch8
A. Enters at C6; joins with the contralateral vertebral to form the basilar artery
B. Enters at C4; joins the circle of Willis directly
C. Enters at C7; joins with the contralateral vertebral to form the basilar artery
D. Enters at C6; joins the internal carotid to form the basilar artery
✓ Answer: A — Enters at C6; bilateral vertebrals unite to form basilar artery
The vertebral artery (first branch of the subclavian) ascends through the transverse foramina of C6 to C1 (skipping C7), then loops behind the atlas (C1) and enters the skull through the foramen magnum. Inside the skull, the two vertebral arteries (left + right) unite at the pontomedullary junction to form the basilar artery. The basilar artery then gives off the posterior cerebral arteries which connect to the ICA via posterior communicating arteries (completing the Circle of Willis).
⚠ C7's transverse foramen is typically small and does NOT carry the vertebral artery (B is wrong for this reason). D is wrong: the internal carotid does not form the basilar — only the two vertebral arteries merge to form the basilar. The vertebral arteries join each other, not the ICA.
Q18
Regarding the renal arteries, which statement is CORRECT?
Unit 11 Slides · Gray's 4e Ch4
Unit 11 Slides · Gray's 4e Ch4
A. Both renal arteries arise at L1; the left is longer and crosses behind the inferior vena cava
B. Both arise at L1; the right is longer because it crosses behind the inferior vena cava
C. The renal arteries arise at L3 from the aorta, level with the renal hilum
D. The right renal artery is shorter than the left because the right kidney sits higher
✓ Answer: B — Both at L1; right is longer, crossing behind the IVC
The renal arteries arise from the lateral walls of the abdominal aorta at the level of L1–L2 (just below the SMA). The right renal artery is longer because it must cross behind the inferior vena cava (IVC) to reach the right kidney. The left renal artery is shorter as the left kidney is closer to the aorta. The right kidney sits slightly lower than the left (displaced by the liver), but the greater distance the right artery must travel (around the IVC) makes it longer.
⚠ A has the laterality reversed. C has the wrong vertebral level (L3 is IMA). D is wrong: the right renal artery is longer, not shorter. The key fact: right artery = longer because it crosses behind the IVC.
Q19
The superior phrenic arteries are described as the first paired branches of the abdominal aorta. From which part of the aorta do they arise, and what do they supply?
Unit 11 Slides · Gray's 4e Ch4
Unit 11 Slides · Gray's 4e Ch4
A. Thoracic aorta at T8; supply the diaphragm inferiorly
B. Abdominal aorta at L1; supply the diaphragm and suprarenal glands
C. Abdominal aorta just below the aortic hiatus at T12; supply the superior surface of the diaphragm
D. Descending thoracic aorta at T6; supply the diaphragm superiorly
✓ Answer: C — Abdominal aorta just below aortic hiatus at T12; supply superior diaphragm
The superior (inferior) phrenic arteries are the first paired parietal branches of the abdominal aorta, arising just below the aortic hiatus at T12. They supply the inferior surface of the diaphragm (sometimes called inferior phrenic arteries in some texts, but the TMU slides describe them as the first paired branches at T12). The diaphragm also receives blood from the musculophrenic and pericardiophrenic arteries superiorly, and the intercostal arteries.
⚠ A is wrong: the thoracic aorta at T8 is where the IVC passes through the diaphragm, not where phrenic arteries arise. C is wrong: L1 is the SMA level. D is wrong: T6 is too high. The first abdominal aortic branches at T12 = phrenic arteries.
Q20
The ligamentum arteriosum connects which two vessels, and what is its embryological origin?
Unit 11 Slides · Gray's 4e Ch3
Unit 11 Slides · Gray's 4e Ch3
A. Connects the pulmonary trunk to the ascending aorta; remnant of the ductus venosus
B. Connects the right pulmonary artery to the ascending aorta; remnant of the foramen ovale
C. Connects the left pulmonary artery to the descending aorta; remnant of the ductus arteriosus
D. Connects the left pulmonary artery to the aortic arch; remnant of the ductus arteriosus
✓ Answer: D — Left pulmonary artery to aortic arch; remnant of ductus arteriosus
The ligamentum arteriosum is a fibrous cord connecting the left pulmonary artery to the underside of the aortic arch (near the origin of the left subclavian). It is the obliterated remnant of the ductus arteriosus, which in fetal life allowed blood to bypass the lungs (high pulmonary resistance) by shunting from the pulmonary trunk to the aorta. It closes within 2–3 days of birth (functional closure) and fibroses by 2–3 weeks. Patent ductus arteriosus (PDA) = failure of closure → left-to-right shunt.
⚠ A = wrong vessel (pulmonary trunk, not left pulmonary artery) and wrong remnant (ductus venosus obliterates to form ligamentum venosum in the liver). C = wrong side (right pulmonary artery). D = wrong attachment point (descending aorta, not aortic arch). The ligamentum arteriosum attaches to the aortic arch.
D1
Circle of Willis
+
An arterial anastomotic ring at the base of the brain, formed by the junction of the internal carotid system and the vertebrobasilar system. Components (clockwise): anterior communicating artery (connects left and right anterior cerebral arteries) → bilateral anterior cerebral arteries → bilateral internal carotid arteries → bilateral posterior communicating arteries → bilateral posterior cerebral arteries (arising from the basilar). The circle provides collateral circulation: if one vessel is occluded, blood can be rerouted. In practice, the circle is often incomplete (variant anatomy). Clinical: Berry (saccular) aneurysms most commonly occur at the junctions of communicating arteries; rupture → subarachnoid haemorrhage.
Gray's Anatomy 4e Ch8 · Unit 11 Slides
D2
Coeliac Trunk
+
The first unpaired visceral branch of the abdominal aorta, arising at the level of T12 just below the aortic hiatus of the diaphragm. It is a short (about 1–2 cm) wide trunk that immediately trifurcates into three branches: (1) Left gastric artery — smallest; supplies lesser curvature of stomach and lower oesophagus; (2) Splenic artery — largest and most tortuous; supplies spleen, pancreas, short gastric arteries, and left gastroepiploic; (3) Common hepatic artery — gives rise to gastroduodenal artery and continues as hepatic artery proper to the liver. The coeliac trunk supplies the foregut (lower oesophagus to proximal duodenum) and its solid organs (liver, spleen, pancreas). Mnemonic: LSC.
Gray's Anatomy 4e Ch4 · Unit 11 Slides
D3
Watershed Area (SMA / IMA)
+
The zone of bowel at the boundary between the superior mesenteric artery (SMA) and the inferior mesenteric artery (IMA) territories, located at the splenic (left colic) flexure of the large intestine. This area receives relatively poor blood supply because the distal branches of both vessels are smallest here. The marginal artery of Drummond normally connects the two systems, but this may be absent or inadequate at the splenic flexure. Clinical significance: the splenic flexure is the most vulnerable site for ischaemic colitis, particularly after surgery involving the abdominal aorta (e.g. aortic aneurysm repair with IMA ligation) or states of low flow (shock, athero-embolism). Presents with left-sided abdominal pain and bloody diarrhoea.
Gray's Anatomy 4e Ch4 · Unit 11 Slides
D4
Femoral Triangle (NAVY)
+
A triangular space in the upper anterior thigh. Boundaries: superiorly = inguinal ligament; medially = medial border of adductor longus; laterally = medial border of sartorius; floor = iliopsoas (lateral) + pectineus (medial); roof = fascia lata (with saphenous opening for great saphenous vein). Contents (lateral to medial, mnemonic NAVY): Nerve (femoral nerve, outside the femoral sheath), Artery (femoral artery), Vein (femoral vein), Y (femoral canal — containing deep inguinal lymph nodes and fat; site of femoral hernia). The femoral sheath encloses only the artery, vein, and canal (not the nerve). Clinical: femoral pulse at midinguinal point; femoral artery catheterisation (coronary angiography); femoral hernia medial to the femoral vein in the femoral canal.
Gray's Anatomy 4e Ch5 · Unit 11 Slides · 2022 Review
D5
Arterial Anastomosis
+
A communication between two or more arteries (or their branches) that provides an alternative pathway for blood flow if one vessel is occluded — the basis of collateral circulation. Types: (1) End-to-end — direct joining of two arteries; (2) Side-to-side; (3) Via arteriolar networks in a capillary bed. An artery without anastomosis is an end artery (e.g. central artery of the retina, splenic arterioles, renal interlobular arteries) — occlusion of an end artery causes infarction of the territory it supplies, with no collateral compensation. Examples of clinically important anastomoses: Circle of Willis (brain); palmar arches (hand); marginal artery of Drummond (colon); geniculate anastomosis (knee). Arteriovenous anastomoses: direct shunts bypassing capillaries; found in skin (temperature regulation), erectile tissue, and tumour vasculature.
Gray's Anatomy 4e Ch1 · Unit 11 Slides
D6
Ligamentum Arteriosum
+
A short fibrous cord connecting the left pulmonary artery to the inferior surface of the aortic arch (near the origin of the left subclavian artery). It is the obliterated remnant of the ductus arteriosus, a fetal shunt that directed oxygenated blood from the pulmonary trunk directly into the aorta (bypassing the high-resistance fetal pulmonary circulation). At birth, rising PO⊂2; and falling prostaglandins cause functional closure within 24–48 hours; anatomical obliteration into the fibrous ligamentum by 2–3 weeks. Patent ductus arteriosus (PDA): failure of closure → left-to-right shunt → continuous “machinery” murmur; treated with indomethacin (prostaglandin inhibitor) in premature neonates, or surgical ligation. The left recurrent laryngeal nerve hooks around the ligamentum arteriosum, making it vulnerable in surgery of the aortic arch.
Gray's Anatomy 4e Ch3 · Unit 11 Slides
Essay 1
Describe the course of the aorta from the aortic valve to its bifurcation, naming its four divisions and the principal branches given off at each level.
10 marks
Division 1 — Ascending aorta
Begins at the aortic valve (T4/T5 level) and ascends to the sternal angle. Only branches: right and left coronary arteries from the aortic sinuses of Valsalva. Enclosed with the pulmonary trunk in the pericardium.
Division 2 — Aortic arch
Arches over the left bronchus from sternal angle to T4 vertebra on the left. Three branches (right to left):
- Brachiocephalic (innominate) trunk → divides behind the right sternoclavicular joint into right subclavian + right common carotid
- Left common carotid artery
- Left subclavian artery
The ligamentum arteriosum (remnant ductus arteriosus) connects the arch to the left pulmonary artery.
Division 3 — Descending thoracic aorta
T4 to T12 (aortic hiatus of diaphragm). Principal branches:
- Posterior intercostal arteries (3rd–11th, paired) — 9 pairs
- Subcostal arteries (12th pair)
- Bronchial arteries (2 left, 1 right) — nutritive supply to bronchi
- Oesophageal arteries — direct aortic branches to mid-oesophagus
- Superior phrenic arteries (variable)
Division 4 — Abdominal aorta
T12 to L4 (bifurcation into left and right common iliac arteries). Branches:
- Paired parietal: inferior phrenic (T12), lumbar arteries (×4 pairs)
- Unpaired visceral: coeliac trunk (T12) → foregut; superior mesenteric artery (L1) → midgut; inferior mesenteric artery (L3) → hindgut
- Paired visceral: middle suprarenal, renal arteries (L1–L2), gonadal arteries (L2)
- Terminal: left and right common iliac arteries at L4; median sacral artery (unpaired posterior branch)
Marking (10 marks): Ascending aorta + coronary arteries (1) · Aortic arch + 3 correct branches in order (2) · Descending thoracic aorta intercostal + bronchial (1.5) · Abdominal aorta unpaired visceral 3 vessels + levels (2) · Paired visceral: suprarenal, renal, gonadal (1) · Parietal branches: phrenic + lumbar (1) · Bifurcation at L4 into common iliac (0.5) · Ligamentum arteriosum / ductus arteriosus (1)
Essay 2
Describe the coronary arteries: origin, named branches, territories supplied, the concept of dominant circulation, and the correlation of each major coronary territory with the type of myocardial infarction produced by its occlusion.
10 marks
Origin
Both coronary arteries arise from the aortic sinuses (sinuses of Valsalva) at the root of the ascending aorta, just above the aortic valve cusps. The right coronary artery (RCA) from the right aortic sinus; the left coronary artery (LCA) from the left aortic sinus.
Right Coronary Artery (RCA)
- Runs in the right atrioventricular (coronary) groove.
- Major branches: SA nodal artery (~60% from RCA); right marginal artery (right ventricular free wall); posterior descending (interventricular) artery (in right-dominant circulation — ~85% of people) — supplies posterior 1/3 of interventricular septum and inferior LV wall.
- AV nodal artery from RCA (in right-dominant circulation).
- MI correlation: RCA occlusion → inferior MI (ST elevation in leads II, III, aVF); also causes AV block (AV node ischaemia) and SA node dysfunction.
Left Coronary Artery (LCA)
- Short left main stem (1–2 cm) → divides into two major branches at the left AV groove.
- Left anterior descending (LAD): runs in the anterior interventricular groove; supplies the anterior 2/3 of interventricular septum (via septal perforators) and the anterior wall of the left ventricle and apex. The “widow maker” — occlusion → large anterior MI (ST elevation V1–V4), often with cardiogenic shock or ventricular fibrillation.
- Circumflex artery: runs in the left AV groove; supplies the lateral wall of the left ventricle and the left atrium. In left-dominant circulation (~15%), the circumflex gives the posterior descending artery. Occlusion → lateral MI (ST elevation I, aVL, V5–V6).
Dominant Circulation
Determined by which artery gives the posterior descending (interventricular) artery. Right dominant (~85%): RCA gives posterior descending. Left dominant (~8%): circumflex gives posterior descending. Co-dominant (~7%): both contribute.
Venous Drainage
Most cardiac venous blood drains via the coronary sinus (in the posterior atrioventricular groove) into the right atrium. The great cardiac vein (accompanies LAD), middle cardiac vein (accompanies posterior descending), and small cardiac vein (accompanies RCA) are its major tributaries.
Marking (10 marks): RCA origin + AV groove + SA node branch (1) · RCA marginal + posterior descending (1) · RCA inferior MI (1) · LCA left main stem + bifurcation (1) · LAD territory + septal perforators + anterior MI (2) · Circumflex territory + lateral MI (1) · Dominant circulation definition (1) · AV node supply (1) · Coronary sinus venous drainage (1)
Essay 3
Describe the arteries of the upper limb from the subclavian artery to the palmar arches. Name key branches at each level and state the clinically palpable pulse sites.
8 marks
Subclavian Artery
Arises as the 3rd branch of the aortic arch on the left; from the brachiocephalic trunk on the right. Major branches: vertebral artery (1st branch; ascends through C6–C1 transverse foramina); internal thoracic (internal mammary) artery; thyrocervical trunk; costocervical trunk. Becomes the axillary artery at the lateral border of the 1st rib.
Axillary Artery
Three parts relative to pectoralis minor. Key branches: subscapular artery (largest axillary branch; thoracodorsal + circumflex scapular); anterior and posterior circumflex humeral arteries (encircle the surgical neck of humerus). Becomes the brachial artery at the lower border of teres major.
Brachial Artery
Runs in the medial bicipital groove. Major branch: profunda brachii (deep brachial) → runs posteriorly with the radial nerve in the spiral groove; supplies posterior compartment. The brachial artery divides at the cubital fossa (opposite neck of radius) into: radial (lateral) + ulnar (medial). Clinical pulse: brachial pulse at medial side of cubital fossa (BP measurement; brachial artery catheterisation).
Radial Artery
Descends lateral to flexor carpi radialis. Radial pulse: anterior wrist, lateral to FCR tendon. Continues into the anatomical snuffbox and through the 1st dorsal interosseous space into the palm to form the deep palmar arch (mainly radial).
Ulnar Artery
Descends deep to the superficial forearm flexors, then lateral to flexor carpi ulnaris. Ulnar pulse: wrist medial to FCU. Passes superficial to the flexor retinaculum via Guyon's canal and forms the superficial palmar arch (mainly ulnar). Allen's test assesses the patency of both arches before radial artery cannulation.
Palmar Arches
- Superficial palmar arch: mainly ulnar + superficial branch of radial. Lies superficial to the flexor tendons; gives common palmar digital arteries → proper palmar digital arteries to fingers.
- Deep palmar arch: mainly radial + deep branch of ulnar. Deep to flexor tendons; gives palmar metacarpal arteries.
Marking (8 marks): Subclavian + vertebral artery as branch (1) · Transition points: lateral 1st rib + lower teres major + cubital fossa (1.5) · Profunda brachii from brachial (1) · Radial pulse site (1) · Ulnar pulse site (0.5) · Superficial palmar arch (ulnar dominant) (1) · Deep palmar arch (radial dominant) (1) · Allen's test clinical application (1)
Essay 4
Describe the arteries of the lower limb from the external iliac to the foot, naming the key branches and the clinically palpable pulse sites used in peripheral vascular assessment.
8 marks
External Iliac Artery
Arises from the common iliac at L4 and descends along the pelvic brim. Branch: inferior epigastric artery (forms medial boundary of deep inguinal ring). Becomes the femoral artery at the midpoint of the inguinal ligament (below it).
Femoral Artery
Enters the femoral triangle (order lateral to medial: NAVY). Key branches: profunda femoris (deep femoral) artery — main artery to the thigh (lateral + medial circumflex femoral, perforating arteries). The femoral artery exits through the adductor (Hunter's) canal and becomes the popliteal artery at the adductor hiatus (adductor magnus tendon). Femoral pulse: at the midinguinal point (midpoint of inguinal ligament, halfway between ASIS and pubic symphysis).
Popliteal Artery
In the popliteal fossa (behind the knee). Branches: genicular arteries (5) forming the geniculate anastomosis around the knee. Divides at the lower border of popliteus into anterior tibial and posterior tibial. Popliteal pulse: palpated in the popliteal fossa with the knee slightly flexed (deep and often difficult to feel).
Anterior Tibial Artery
Passes through the interosseous membrane into the anterior compartment of the leg. Supplies anterior leg muscles (tibialis anterior, extensor muscles). Continues distally as the dorsalis pedis artery at the ankle. Dorsalis pedis pulse: dorsum of foot, lateral to extensor hallucis longus tendon, over the navicular/cuneiform.
Posterior Tibial Artery
Descends in the posterior (deep) compartment, deep to flexor digitorum longus. Major branch: fibular (peroneal) artery (given off proximally; runs along medial aspect of fibula, supplies lateral compartment muscles via perforators, and posterior compartment). The posterior tibial passes behind the medial malleolus (under the flexor retinaculum) and divides into medial and lateral plantar arteries in the foot. Posterior tibial pulse: behind the medial malleolus, between the malleolus and the Achilles tendon.
Plantar Arches
Lateral plantar artery curves across the foot and joins the deep branch of the dorsalis pedis to form the deep plantar arch, which gives plantar metatarsal and digital arteries.
Marking (8 marks): External iliac → femoral transition at inguinal ligament (1) · NAVY mnemonic in femoral triangle (1) · Profunda femoris as main thigh supply (1) · Femoral → popliteal at adductor hiatus (0.5) · Popliteal division at lower border popliteus (0.5) · Anterior tibial → dorsalis pedis + pulse site (1) · Posterior tibial + fibular branch (1) · Posterior tibial pulse site behind medial malleolus (1) · Plantar arch (1)
Essay 5
Describe the blood supply to the head and neck: the common carotid arteries, the branches of the external carotid artery, the territory of the internal carotid artery, the vertebral artery, and the Circle of Willis. Include the clinical relevance of each.
10 marks
Common Carotid Arteries
Right common carotid: from brachiocephalic trunk. Left common carotid: directly from aortic arch. Both ascend in the carotid sheath (with the internal jugular vein and vagus nerve) and bifurcate at the level of the upper border of thyroid cartilage (C4) into internal and external carotid arteries. The carotid sinus (baroreceptor) and carotid body (chemoreceptor) are at the bifurcation. Clinical: carotid bruit → atherosclerotic stenosis; carotid endarterectomy for high-grade stenosis to prevent stroke.
External Carotid Artery (ECA)
Supplies the face, scalp, and neck. Eight branches — mnemonic SALFOPMS:
- Superior thyroid — first branch; supplies upper thyroid and larynx (runs with superior laryngeal nerve)
- Ascending pharyngeal — only branch from medial side
- Lingual — supplies tongue (passes deep to hyoglossus)
- Facial — palpable at mandible lower border; supplies face; anastomoses with ophthalmic (ICA territory)
- Occipital — posterior scalp
- Posterior auricular — behind the ear
- Maxillary — terminal branch; gives middle meningeal artery (through foramen spinosum → extradural haematoma if ruptured)
- Superficial temporal — terminal branch; palpable in front of the tragus
Internal Carotid Artery (ICA)
Supplies the brain and eye. No branches in the neck. Enters cranium through the carotid canal (petrous temporal bone). Gives off: ophthalmic artery (first intracranial branch; central artery of retina is an end artery — occlusion → sudden painless monocular blindness); anterior cerebral artery (ACA; medial hemispheres → leg area of cortex); middle cerebral artery (MCA; largest branch; lateral hemisphere → arm and face cortex; Broca's/Wernicke's areas; occlusion = commonest cause of stroke); posterior communicating artery (joins basilar system). Clinical: ICA stenosis → TIA/stroke; ICA aneurysm at posterior communicating junction → CN III palsy (ptosis, dilated pupil, eye down and out).
Vertebral Artery
First branch of the subclavian. Ascends through transverse foramina C6 to C1 (C7 excluded). Enters cranium through foramen magnum. Left and right vertebral arteries unite at the pontomedullary junction to form the basilar artery. The basilar gives: anterior inferior cerebellar (AICA), superior cerebellar, and the posterior cerebral arteries (PCAs). Clinical: vertebrobasilar insufficiency → dizziness, ataxia, diplopia, drop attacks; caused by cervical osteophytes compressing transverse foramina or atherosclerosis.
Circle of Willis
Anastomotic ring at the base of the brain connecting anterior (ICA) and posterior (vertebrobasilar) systems. Completed by: anterior communicating artery (connects two ACAs) and paired posterior communicating arteries (each connecting ICA to PCA). Provides collateral flow. Clinical: berry aneurysms form at the bifurcation points (most commonly anterior communicating artery and posterior communicating artery junctions) → subarachnoid haemorrhage (sudden “thunderclap headache”, worst of life).
Marking (10 marks): Common carotid bifurcation level + carotid sinus/body (1) · ECA 8 branches in SALFOPMS order (2) · Middle meningeal artery from maxillary + foramen spinosum + extradural haematoma (1) · ICA territory: brain + eye (1) · Ophthalmic artery as end artery + monocular blindness (1) · MCA as commonest stroke vessel (1) · Vertebral artery: subclavian branch, C6–C1, basilar artery formation (1.5) · Circle of Willis: communicating arteries + berry aneurysm (1.5)