Some operators have been content to insert a needle over the
approximate site of the internal ring and then to force it downward
until it lies as close to the internal ring as they can approximate
and then to throw in a mass of paraffin sufficient to occlude the
canal at this point.
If the needle is inserted about half an inch above the middle of
Poupart's ligament it will be over the site of the normal internal
ring. After the needle passes through the subcutaneous fat it will be
felt to strike the firm fibrinous layers of the external wall of the
inguinal canal. After the needle has passed through this firm layer it
will enter the loose cellular tissue in the neighborhood of the
internal ring. If the injection is diffused over an area of an inch or
an inch and a half in circumference the internal ring is likely to be
plugged for the time by the injection.
The larger Hernia.
Should the hernia be large the injection should be made closer to the
pubes, but injection at the internal ring is not sufficient, the canal
should also be injected with a certain amount of the paraffin and
vaseline.
The canal may be injected by passing the needle directly through the
outer wall of the inguinal canal, remembering its course about
one-half inch above the line of Poupart's ligament.
The most satisfactory plan of injecting where the operator can
successfully follow the technic is to find the external ring and then
insert the needle directly into the external ring close to its upper
margin and to carry the needle along for at least two inches. The
suction technic should be followed and the needle should be moved in
all directions as it is withdrawn and the deposit diffused as much as
possible.
About the external ring itself and directly between the pillars of the
external ring a certain amount of the injection should be placed.