Page 139 - Clinical Anatomy
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124 The abdomen and pelvis
to the ischial tuberosity then turns medially to the base of the bladder. Here
it joins the more laterally placed seminal vesicle to form the ejaculatory duct
which traverses the prostate to open into the prostatic urethra at the veru-
montanum on either side of the utricle.
Clinical features
Infection may track from bladder and urethra along the vas to the epi-
didymis (acute epididymitis).
The operation of bilateral vasectomy is a common procedure for male
sterilization. The vas is identified by its very firm consistency which, in
coaching days, was likened to whipcord but which today might, more
aptly, be compared with fine plastic tubing.
The seminal vesicles
These are coiled sacculated tubes 2in (5cm) long which can be unravelled
to three times that length. They lie, one on each side, extraperitoneally at
the bladder base, lateral to the termination of the vasa. Each has common
drainage with its neighbouring vas via the ejaculatory duct (Fig. 87). In
spite of their name, they do not act as receptacles for semen, although their
secretion does contribute considerably to the seminal fluid.
Clinical features
The vesicles can be felt on rectal examination if enlarged; this occurs typi-
cally in tuberculous infection.
The bony and ligamentous pelvis
The pelvis is made up of the innominate bones, the sacrum and the coccyx,
bound to each other by dense ligaments.
The os innominatum (Fig. 92)
Examine the bone and revise the following structures.
The ilium with its iliac crest running between the anterior and posterior
superior iliac spines; below each of these are the corresponding inferior spines.
Well-defined ridges on its lateral surface are the strong muscle markings of
the glutei. Its inner aspect bears the large auricular surface which articulates
with the sacrum. The iliopectineal line runs forward from the apex of the
auricular surface and demarcates the true from the false pelvis.
The pubis comprises the body and the superior and inferior pubic rami.
