One of the common depictions of battle surgery from these times is of 4 men holding the patient down, while he drinks whiskey and the surgeon saws through his bone to amputate. ie Difficult
A guillotine could be made from 2 bits of wood, a rope and a blade. It would have been rapid, "clean" and portable. It's always struck me as odd that it wasn't used for this purpose. Given the amount of swords around I'm sure a grinding stone would have been available for sharpening.
Was this just simply overlooked? Did anyone ever use a guillotine for this type of surgery? Is there something I'm missing?
Amputation wasn't just a matter of cutting a limb off. There was a surgical procedure to be followed.
If you used a guillotine to remove a limb you've simply sliced open a whole new bunch of blood vessels with a very clean cut. The patient would either die of blood loss, or take months and months to grow skin over the stump.
The procedure for amputations that I've seen from surgical diagrams was as follows:
the muscle and tissue at the amputation point was cut down to the bone, leaving a larger area of flesh on one side of the cut. Throughout this blood vessels would be tied off or cauterised to reduce blood loss.
The now detached muscle tissue was slid up the bone and the bone sawed through at a higher point than you'd expect. Otherwise the end would keep ripping through the healing skin or be much more open to the environment and infection.
the tissue was allowed to slide back down the bone, the extra flap of flesh folded over the stump and sewn up.
Also there's the fact that a guillotine would be a lot harder to transport with an army than a bag of knives and saws, and not as easy to make as you described. You'd need a LARGE specially made blade to fall from a great height on well made tracks. A sword would not have the mass to fall through an arm or leg.
EDIT: Added a source: Amputation procedures from civil war
Note the flaps of muscle and skin to be folded over the stumps.
First, anesthesia using ether and chloroform was introduced in the 1840s, and U.S. Army doctors began using anesthesia for field amputations during the Mexican-American War. There are no hard records on what percentage of amputations during the Civil War involved anesthetics (mostly chloroform). U.S. Army records indicate that about 175,000 soldiers received treatment for an arm or leg wound (30,000 of those limbs were amputated). Later records indicate, judging from the amount used up, that about half of those 175,000 received anesthesia during treatment. It's likely that amputations were first in line for chloroform.
As for a guillotine, we're talking about an eight-pound blade that has to be balanced in a carefully constructed 15-foot frame. You don't want a guillotine blade landing a few inches off when you're slicing through someone's thigh. It's just not precise enough, and it's certainly not something a doctor wants to lug around a battlefield triage area - especially when, again and despite modern myths, the majority of their patients would be unconscious.