A 65-year-old man undergoes left radical nephrectomy. Postoperatively he reports ejaculatory dysfunction (dry ejaculation). Which autonomic structure was most likely inadvertently damaged?
- A Pelvic splanchnic nerves (S2-S4)
- B Hypogastric nerve (sympathetic) ✓
- C Pudendal nerve
- D Inferior hypogastric plexus (parasympathetic component)
Explanation
Emission (movement of seminal fluid into the posterior urethra) is a sympathetic function mediated by the hypogastric nerves (L1-L2 preganglionic fibres travelling in the superior hypogastric plexus and hypogastric nerves to the inferior hypogastric plexus). Damage during retroperitoneal dissection for nephrectomy disrupts sympathetic emission, causing dry orgasm (anejaculation/retrograde ejaculation). Pelvic splanchnic nerves (S2-S4) mediate erection via parasympathetic vasodilation. The pudendal nerve mediates somatic motor control of the bulbospongiosus (ejaculatory propulsion) and sensation — its damage causes different deficits.
Reference: BD Chaurasia's Human Anatomy, 8th ed.
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Written and medically reviewed by the StethoPrep medical team.