Horseshoe Kidney with Surplus Renal Arteries, Veins, and Roots of the Ureters

Abstract

We report the anatomical findings of a kidney discovered in a 92‐year‐old male during a routine dissection of the abdominal viscera performed by medical students at the Oakland University William Beaumont School of Medicine. The lower poles of the kidney are fused together, forming an isthmus anterior to the aorta and inferior vena cava at the L3‐L4 vertebral level. The right and left kidneys ascend past the isthmus, forming a “U” shape, the defining feature of a horseshoe kidney. The left kidney stops prematurely, approximately 3.2 cm below the inferior mesenteric artery at the level of the left inferior renal artery. The right kidney drains into superior, inferior, and middle renal arteries which have three, two, and one branches respectively. Due to the size and position of the hilum, five separate roots extend outside the kidney into the right ureter. The left side is supplied by a superior and inferior renal artery, each dividing into two branches. The left inferior renal artery branches off the ventral face of the descending aorta. The left renal vein notably has three prominent tributaries from the kidney and an additional branch of the left adrenal vein. Six roots extend from the left hilum and drain into the left ureter. In total, the kidney has nine veins, six arteries, and eleven ureteric branches draining into the left and right ureters. These findings will be useful in regard to research and surgery on other horseshoe kidneys.