CSFA Surgical Anatomy and Physiology 3 — Questions and Answers
Question 1: Which nerve is at risk during dissection along the medial aspect of the axilla during axillary lymph node dissection?
- Musculocutaneous nerve
- Thoracodorsal nerve
- Long thoracic nerve (Correct answer)
- Median nerve
Correct answer: Long thoracic nerve
The long thoracic nerve runs along the serratus anterior on the medial axillary wall and, if injured, causes a winged scapula.
Question 2: The pylorus regulates gastric emptying via contraction of which muscle layer?
- Inner longitudinal smooth muscle
- Outer circular smooth muscle forming the pyloric sphincter (Correct answer)
- Muscularis mucosae
- Oblique muscle layer
Correct answer: Outer circular smooth muscle forming the pyloric sphincter
The pyloric sphincter is formed by a thickened ring of circular smooth muscle that controls passage of chyme into the duodenum.
Question 3: During a thyroidectomy, which structure must be identified to prevent hypocalcemia postoperatively?
- Cervical sympathetic chain
- External branch of superior laryngeal nerve
- Parathyroid glands (Correct answer)
- Thoracic duct
Correct answer: Parathyroid glands
Inadvertent removal or devascularization of the parathyroid glands leads to postoperative hypocalcemia due to loss of PTH secretion.
Question 4: The hepatoduodenal ligament (portal triad) contains all of the following EXCEPT:
- Portal vein
- Hepatic artery proper
- Common bile duct
- Hepatic vein (Correct answer)
Correct answer: Hepatic vein
The hepatic veins drain directly into the inferior vena cava and are not part of the portal triad within the hepatoduodenal ligament.
Question 5: Which layer of the peritoneum directly covers the abdominal organs and is reflected to form mesenteries?
- Parietal peritoneum
- Visceral peritoneum (Correct answer)
- Retroperitoneum
- Omentum
Correct answer: Visceral peritoneum
Visceral peritoneum directly invests the organs and is continuous with the mesenteries that suspend them from the posterior abdominal wall.
Question 6: In the context of surgical hemostasis, which coagulation pathway is initiated when tissue factor is exposed at a wound site?
- Intrinsic (contact activation) pathway
- Extrinsic (tissue factor) pathway (Correct answer)
- Fibrinolytic pathway
- Common pathway only
Correct answer: Extrinsic (tissue factor) pathway
Exposed tissue factor binds factor VIIa to initiate the extrinsic pathway, which rapidly activates the coagulation cascade at sites of vascular injury.
Question 7: The saphenous nerve, a branch of the femoral nerve, accompanies which vessel and is at risk during saphenous vein harvest?
- Femoral artery
- Greater saphenous vein (Correct answer)
- Popliteal vein
- Lesser saphenous vein
Correct answer: Greater saphenous vein
The saphenous nerve runs alongside the greater saphenous vein, particularly below the knee, and can be injured during vein harvest causing medial leg paresthesia.
CSFA Surgical Anatomy and Physiology 3
Which nerve is at risk during dissection along the medial aspect of the axilla during axillary lymph node dissection?