Page 124 - Clinical Anatomy

ECA2 7/18/06 6:42 PM Page 109

The urinary tract 109

If more room is required, the lateral edge of quadratus lumborum may be
divided and also the 12th rib excised, care being taken to push up, but not to
open, the pleura, which crosses the medial half of the rib.

The ureter
The ureter is 10in (25cm) long and comprises the pelvis of the ureter (see
above) and its abdominal, pelvic and intravesical portions.
The abdominal ureter lies on the medial edge of psoas major (which sepa-
rates it from the tips of the transverse processes of L2–L5) and then crosses
into the pelvis at the bifurcation of the common iliac artery in front of the
sacroiliac joint. Anteriorly, the right ureter is covered at its origin by the
second part of the duodenum and then lies lateral to the inferior vena cava
and behind the posterior peritoneum. It is crossed by the testicular (or
ovarian), right colic, and ileocolic vessels. The left ureter is crossed by the
testicular (or ovarian) and left colic vessels and then passes above the pelvic
brim, behind the mesosigmoid and sigmoid colon to cross the common iliac
artery immediately above its bifurcation.
The pelvic ureter runs on the lateral wall of the pelvis in front of the
internal iliac artery to just in front of the ischial spine; it then turns for-
wards and medially to enter the bladder. In the male it lies above the
seminal vesicle near its termination and is crossed superficially by the vas
deferens (see Fig. 87). In the female, the ureter passes above the lateral
fornix of the vagina 0.5in (12mm) lateral to the supravaginal portion of
the cervix and lies below the broad ligament and uterine vessels (see
Fig. 104).
The intravesical ureter passes obliquely through the wall of the bladder
for 0.75in (2cm); the vesical muscle and obliquity of this course produce
respectively a sphincteric and valve-like arrangement at the termination of
this duct.

Blood supply
The ureter receives a rich segmental blood supply from all available arteries
along its course: the aorta, and the renal, testicular (or ovarian), internal
iliac and inferior vesical arteries.

Clinical features

1◊◊The ureter is readily identified in life by its thick muscular wall which is
seen to undergo worm-like (vermicular) writhing movements, particularly
if gently stroked or squeezed.
2◊◊Throughout its abdominal and the upper part of its pelvic course, it
adheres to the overlying peritoneum (through which it can be seen in the
thin subject), and this fact is used in exposing the ureter — as the parietal
peritoneum is dissected upwards, the ureter comes into view sticking to its
posterior aspect.