Again we're far from the shambling undead here with medical zombies.
But they have apparently been experimented with all around the
world, usually during times of war and with some of the most odd
accounts coming from the Nazi's around WWII. However the stories
about Nazi Zombies are so tied up and confused with occult practices
and lack any real evidence other than conjecture, we put them
as their own catagorie to prevent this one from rambling all over
the place on tangents.
It sounds a bit ludicrous at first bite, but I present for your
consideration below, video of some of the Russian experiments
at reanimation which date from the 1940's in which a team of scientists
not only reanimate dead dogs, but even severed heads.
Experiments in reanimation using corpses of criminals and battery
devices were done publicly as early as 1803, and who really knows
what happened behind closed doors in those early times of strange
medical experimentation with the exciting new medium, Electricity.
In the '70's in the USA, Dr. R White actually performed head swap
operations on rhesus monkeys and in the 1980's announced he would
be capable of doing this procedure on a human being... Though
so far no one has volunteered to try this out.
Considering the evidence of Cold War research by both Russia and
the USA into some pretty wacky sounding areas that actually turned
out to hold some water and be functional (Remote Viewing for example),
medically created human zombies are not completely unbelievable.
We're going to run with this idea and present the following hypothesis....
If you start taking a look at these medical ventures
and imagine the idea of a medical procedure being developed and
used to create medically revived corpses who have had certain
higher brain areas tampered with (basically advanced lobotomies).
These reanimated dead are controllable either by implanted devices
which would give outside control of a human body in a way similar
to your average remote control car. Or alternatively, without
an implanted device simply by verbal direction. Suddenly you have
a scenario on your hands of independently controlled Zombies.
With that, it's not hard to run a little further and imagine a
squad of these remote-control bodies that could be sent into dangerous
areas, perhaps to test for bombs or find mines. If the brain was
"edited" in such a way that the violent tendencies were left uninhibited
by reason and intellect, which also hampers the amount of strength
the average human has at their disposal at certain times - look
up accounts of people whom in times of great stress have had great
increases in strength, even able to lift cars to free trapped
loved ones. It's also not uncommon for those with brain damage
(either from birth or by accident) to be much stronger than usual
-The remaining conciousness could then be "reprogrammed" to make
them attack humans on sight, and you have an uncontrollable terrifying
and easily replenished weapon.
However one would imagine these medical zombies to be fairly limited
in use, or at least requiring a great deal of direction due to
the amount of the brain that would need to be disabled to remove
will and personality. And unless the procedures for "editing"
the brain could be refined to be a quick task, perhaps the time
taken just to create one of these undead tools would be prohibitive
against mass-producing them.