Common trunk branching from the renal artery to the diaphragm, adrenal gland, and testis: a case report with embryological hypotheses by observation.

The vascular systems of the kidneys and gonads are highly susceptible to variations because of the degeneration of the mesonephros and mesonephric artery and the progressive ascending development of the metanephros. In this report, we present a rare case of a common arterial trunk originating from the left renal artery and supplying the left diaphragm, adrenal gland, and testis. Anatomical dissection of a 95-year-old male was conducted during the 2023 academic year at Tokai University Medical School. The left renal artery had a common trunk that bifurcated to superior and inferior branches, forming a T-shape. The superior branch was distributed in the left adrenal gland and diaphragm, whereas the inferior branch was distributed in the left testis. This anatomical variation likely results from the remnant of the mesonephric artery network structure, particularly the rete arteriosum urogenitale. Understanding such variations is crucial for radiologists and surgeons to avoid potential complications during diagnostic procedures and surgical interventions.