Advanced Sacral Splanchnic Nerves Quiz

Q1. Why are sacral splanchnic nerves unusual compared with many thoracic and lumbar splanchnic nerves?

• They are purely somatic motor nerves
• They carry only preganglionic parasympathetic fibers
• They originate from the vagus nerve
• They predominantly carry postganglionic sympathetic fibers

Q2. Preganglionic sympathetic neurons ultimately associated with sacral splanchnic pathways originate from which region of the spinal cord?

• Cervical enlargement only
• Brainstem vagal nuclei only
• Sacral parasympathetic nuclei only
• Thoracolumbar spinal cord

Q3. How can sympathetic fibers reach sacral sympathetic ganglia despite the absence of sympathetic preganglionic neuron cell bodies in the sacral spinal cord?

• They descend through the pudendal nerves
• They travel through the vagus nerves into the sacrum
• They originate from S2 to S4 parasympathetic neurons
• They descend within the sympathetic trunks from thoracolumbar levels

Q4. A nerve is observed leaving the sacral sympathetic trunk and passing medially toward the inferior hypogastric plexus. What is it most likely to be?

• Pudendal nerve
• Sacral splanchnic nerve
• Obturator nerve
• Pelvic splanchnic nerve

Q5. A nerve arises directly from an S3 anterior ramus and enters the inferior hypogastric plexus. Which nerve is it?

• Lumbar splanchnic nerve
• Pelvic splanchnic nerve
• Greater splanchnic nerve
• Sacral splanchnic nerve

Q6. Which combination correctly compares sacral and pelvic splanchnic nerves?

• Both arise from the sympathetic trunk and carry only sympathetic fibers
• Sacral splanchnic: sympathetic trunk and sympathetic fibers; pelvic splanchnic: S2 to S4 anterior rami and parasympathetic fibers
• Both arise from S2 to S4 and carry only parasympathetic fibers
• Sacral splanchnic: S2 to S4 anterior rami and parasympathetic fibers; pelvic splanchnic: sympathetic trunk and sympathetic fibers

Q7. Which pathway explains how sacral splanchnic fibers become distributed to individual pelvic organs?

• Inferior hypogastric plexus and its visceral branches
• Obturator nerve and its muscular branches
• Femoral nerve and saphenous nerve
• Sciatic nerve and its tibial branch

Q8. During pelvic surgery, injury to sympathetic pathways associated with the inferior hypogastric plexus could interfere with which male reproductive process?

• Spermatogenesis
• Sensory innervation of scrotal skin
• Somatic contraction of the external anal sphincter
• Emission

Q9. Which anatomical fact prevents confusion between sacral splanchnic nerves and pelvic splanchnic nerves during dissection?

• Only sacral splanchnic nerves carry autonomic fibers
• Both arise from exactly the same nerve roots
• Their origins are anatomically different
• Only pelvic splanchnic nerves enter the pelvis

Q10. Which statement best integrates the anatomy and function of the sacral splanchnic nerves?

• They carry sympathetic fibers from the sacral sympathetic trunks into pelvic autonomic plexuses
• They are somatic motor branches of the sacral plexus supplying pelvic floor muscles
• They are sensory branches of the pudendal nerve supplying perineal skin
• They carry parasympathetic fibers directly from S2 to S4 anterior rami