A 25-year-old man is examined for an absent cremasteric reflex on the left side. Which nerve carries the afferent (sensory) limb of the cremasteric reflex?
- A Pudendal nerve
- B Ilioinguinal nerve
- C Genitofemoral nerve (genital branch) ✓
- D Obturator nerve
Correct answer: C. Genitofemoral nerve (genital branch)
Explanation
The cremasteric reflex is mediated entirely by the genital branch of the genitofemoral nerve (L1, L2) for both the afferent (sensory) and efferent (motor) limbs. Stroking the inner thigh stimulates sensory fibers that travel via the genital branch to the sacral cord, and the motor response (cremasteric muscle contraction) is also carried by the genital branch. The ilioinguinal nerve supplies adjacent skin but is not part of this reflex arc. This is standard clinical neuroanatomy.
Reference: Gray's Anatomy, 42nd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.