70. Anatomy | Autonomics of the Abdomen and Pelvis

A 55-year-old male presents with loss of emission during ejaculation but preserved penile erection. Injury to which nerve pathway most likely explains his symptoms?

A. Pelvic splanchnic nerves (S3–S4)
B. Hypogastric nerves (lumbar sympathetics)
C. Pudendal nerves (S2–S4)
D. Greater splanchnic nerve (T5–T9)
E. Cavernous nerves

B

Ejaculation = sympathetic (shoot). The hypogastric nerves (lumbar splanchnics → inferior hypogastric plexus) stimulate internal sphincter closure, ductus deferens contraction, and seminal emission.

• A: Pelvic splanchnics → erection (parasympathetic, “point”).

• C: Pudendal → somatic control of perineal muscles, aids expulsion but not emission.

• D: Greater splanchnic (T5–T9) → foregut.

• E: Cavernous nerves → erection, not emission.

A patient with metastatic ovarian cancer undergoes resection near the ovarian vessels. Postoperatively, she develops disruption of sympathetic innervation to the ovary. Where are the postganglionic cell bodies for this pathway located?

A. Inferior mesenteric ganglion
B. Superior hypogastric plexus
C. Ganglion near the ovarian artery
D. Celiac ganglion
E. Inferior hypogastric plexus

C

Ovarian sympathetics: preganglionic cell bodies T12–L1 → thoracic/lumbar splanchnics → ganglion near ovarian artery (postganglionic) → axons travel with ovarian artery.

• A: Inferior mesenteric → hindgut.

• B: Superior hypogastric → conduit, not ovarian ganglia.

• D: Celiac → foregut.

• E: Inferior hypogastric → pelvic viscera, not ovary.

A 19-year-old male presents with severe epigastric pain radiating to the posterior thorax after binge drinking. Laboratory studies confirm acute pancreatitis. Which sympathetic spinal cord levels provide innervation to the pancreas?

A. T5–T7
B. T7–T9
C. T10–T11
D. T12–L1
E. L1–L2

B

The pancreas is a foregut organ. Its sympathetics come from T7–T9 via the greater splanchnic nerves → celiac ganglion.

• A: T5–T7 → esophagus/stomach (upper foregut).

• C: T10–T11 → midgut.

• D/E: T12–L2 → hindgut/pelvic.

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