An asymptomatic 30-year-old man undergoes ultrasonography that shows a horseshoe kidney. During normal development, the ascent of this kidney was arrested because it became hooked under which structure?

• A Inferior mesenteric artery ✓
• B Superior mesenteric artery
• C Left renal vein
• D Root of the transverse mesocolon

Explanation

The metanephric kidneys ascend from the pelvis to the lumbar region. In horseshoe kidney the lower poles fuse across the midline, and during ascent the fused isthmus is caught under the inferior mesenteric artery, leaving the kidney at the level of L3. The superior mesenteric artery crosses the duodenum and pancreas, not the ascending kidney, so it does not arrest renal ascent.

Reference: Langman's Medical Embryology, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.