Surgical anatomy of kidney relevant to nephron-sparing surgery

The kidneys are paired solid organs that lie within the retroperitoneum on either side of the spine. The normal kidney in the adult male and female weighs approximately 150 g and 135 g, respectively. The dimensions of the kidney are related to the overall body size and the approximate measurements of a normal kidney are 10 to 12 cm in the cranial-caudial dimension, 5 to 7 cm in the medial-lateral dimension, and 3 cm in the anteriorposterior thickness.¹ Kidneys are covered by a thin but tough fibro-elastic capsule, which strips easily from the parenchyma but can hold the sutures better than parenchyma. On the medial surface of either kidney is a depression, the renal hilum, which leads into the space called the ‘renal sinus’. The urine-collecting structures and vessels occupy the renal sinus and exit the kidney through the hilum medially (Figure 2.1).