Torsion
of the testis
Predisposing causes
Torsion of the testis (syn. torsion of the
spermatic cord) is uncommon because the normal fully descended testis is well
anchored and cannot rotate. For torsion to occur one of several abnormalities
must be present.
•
Inversion of the testis is the most common predisposing cause. The testis
is rotated so that it
lies transversely
or upside
down.
•
High investment of the tunica vaginalis causes the testis to hang within
the tunica like a clapper in a bell (Fig. 68.4). Very occasionally, torsion
occurs outside the tunica vaginalis.
•
Separation of the epididymis from the body of the testis permits torsion
of the testis without involving the cord. The twisting is confined to the
pedicle which connects the testis with the epididymis (Fig.
68.5).
Normally,
when there is a violent contraction of the abdominal muscles, the cremaster
contracts as well. The spiral attachment of the cremaster favours rotation
around the vertical axis when this is made possible by one of the abnormalities
described above. Straining at stool, lifting a heavy weight and coitus are all
possible precipitating factors. Alternatively, torsion may develop spontaneously
during sleep.
Clinical
features
Testicular torsion is most common between 10
and 25 years of age and a few cases occur in infancy. Symptoms vary with the
degree of torsion. Most commonly there is sudden agonising pain in the groin
and the lower abdomen. The patient vomits.
Torsion
of a fully descended testis is usually easy to recognise by the high lie of
the testis and thickening of the tender twisted cord which can be palpated above
it. In
mumps orchitis the cord is not particularly thickened. The onset of redness of
the skin after 6 hours or so and the onset of a mild pyrexia may cause confusion
with epididymo-orchitis in the older patient but there will usually be an
associated urethritis. Elevation of the testis reduces the pain of
epididymo-orchitis and makes it
worse in torsion.
Very occasionally, the condition can be convincingly mimicked by a small tense
strangulated inguinal hernia compressing the cord and causing compression of
the pampiniform plexus. If there is any doubt about the diagnosis, the
scrotum should be explored without delay.
It
is almost impossible to distinguish torsion
of an imperfectly descended testis until the parts are exposed at operation. An empty
oedematous hemiscrotum on the side suggests that a tender lump at the external
inguinal ring is a torted testis.
Treatment
In the first hour or so it
may be possible
to untwist the testis by gentle manipulation. If manipulation is successful pain
subsides and the testis is out of danger. However, arrangements should be made
for early operative fixation to avoid recurrent torsion.
Exploration
for testicular torsion can be performed through a scrotal incision. If the
testis is clearly viable when the cord is untwisted, it should be prevented from twisting again by fixation by nonabsorbable
sutures between the tunica vaginalis and the tunica albuginea. The opposite
testis should also be fixed because the anatomical variation responsible for
the torsion is likely to be bilateral. A totally infarcted testis should be
removed — the
patient can be counselled later about a prosthetic replacement if this is
appropriate. If it
is clear that
there has been an established torsion for several days it will not be possible to recover the testis and little is gained by
exploration. The affected testis will become woody-hard and atrophy to a fibrous
nodule. The other testis should be fixed at an early date.
Torsion of a testicular appendage is sometimes
mistaken for acute epididymo-orchitis and cannot be distinguished with certainty
from testicular torsion. The most common structure to twist is the appendix of
the testis (the pedunculated hydatid of Morgagni) but other vestigial structures
related to the testis and epididymis may also rotate. Immediate operation with
ligation and amputation of the twisted appendage cures the condition.
Idiopathic scrotal oedema is a curious condition which occurs between the age of
4 and 12 years and has to be differentiated from torsion. The scrotum is very
swollen but there is very little pain or tenderness. The swelling may extend
into the perineum, groin and penis. It is thought to be an allergic phenomenon —
occasionally
there is eosinophilia. The swelling subsides after a day or so but may recur (Fig.
68.6).