The ureter is a muscular tube, the upper end of which moves to the pelvis-ureter junction, and the lower end ends at the opening of the bladder.

Clinically, it is divided into three segments. The upper segment starts from the pelvis-ureter junction to The upper edge of the skeletal bone, the middle section is equivalent to the skeletal segment, and the lower segment from the lower edge of the skeletal bone to the bladder.

There are three relatively narrow places in the anatomy. One is the renal pelvis-ureter junction, and the other is the ureter crossing the skeletal bone. The third is the place where blood vessels enter the bladder wall. One place is narrower than the other.