Osteotome: the first chainsaw
Before general anesthetics were around, amputations were incredibly painful and dangerous. Bones often splintered and the tissue around the bone was damaged by the harsh impact of a hammer and chisel or the jolts of a saw. Surgeons needed to find a way to speed up the procedure and reduce the risk of complications. The solution came in the form of the osteotome, a device invented by German physician Bernhard Heine in 1830. Also referred to as the chain osteotome, the device is similar to a chisel but beveled on both sides and with a chain and sharp cutting teeth around the outside that cranked manually.
Essentially it is a small chainsaw, the first such device ever invented. The Heine osteotome resulted in a rapid separation of bone during an amputation, a huge advantage for surgeons. Due to the intricate mechanism and heavy usage, not may have survived.
The description of the example below (shown from two angles), on Van Leest Antiques, reads:
A French c. 1850, signed by Charriere a Paris. Constructed of steel (variously with brushed, polished, and blued finishes) with brass fittings, the saw measures 37cm in overall length. There are fine handles bound in sculpted black ebony cut with cross-hatching (for good gripping). A superbly cut serrated link chain rides in shaped grooves in the pulley wheel (turned by hand crank with ball-joint mounted handle) and in the forward nose, allowing cuts in the bone less than 2.5mm thick and approximately 2cm across. Tension in the chain is set and clamped with two thumbscrews, and there is a quick-release blade guard. Twin handles, adjustable in a slot, allow precise control of the cutting position. A long articulated spike, adjustable in length, is designed to keep the instrument steady by stabbing the spike into a table or even into a convenient bone!