Gavriil Ilizarov, an orthopedic surgeon from Russia, is credited with inventing the external fixator—a limb-lengthening device that manually pulls apart bone to increase a patient's height.

For those suffering from polio, congenital limb defects or dwarfism, the new technology meant freedom from scoliosis and wheelchairs. The external fixator procedure was designed to decrease the severity of limb-length discrepancies and increase range of motion.

Still, adding centimeters isn't easy. Ilizarov's 1954 mechanism, which is still used, often causes a significant amount of pain. With the patient under a general anesthetic, doctors drill screws into the top and bottom of the abnormally short bone. The screws are fastened into a metal frame that will stabilize the leg during and after the procedure. After cutting a small incision in the leg, the leg is smacked with a hammer and broken in two. The body's natural healing process fills in the gap with bone tissue, thus lengthening the limb.

Scientific American spoke with Svetlana Ilizarov, the inventor's daughter, to learn more about the history of the limb-lengthening device.

For more on limb-lengthening devices:
New Limb-Lengthening Tech May Reduce Complications for Sufferers of Crippling Deformities