by Jinesh Shah, BS & Samuel Lin, MD FACS
Prosthetics have been in use for over 3500 years – Egyptians pioneered the technology and for the next 1000 years, it was mostly used as a means to recover lost aesthetic appearance with little apparent benefit in the realm of gaining functionality. In the dark ages, prosthetics started gaining functionality when soldiers with battle wounds got fitted with pegs and hooks with internal springs and gears. Prosthetics continued to evolve over the next 500 years as methods of amputation and prosthetic design and functionality improved. 
In the last thirty years, principles of bionic prosthetics, or application of biological tools to design engineering systems, have shaped the world of prostheses. Earlier this February, an Austrian team led by Dr. Aszmann published in Lancet about the successful amputation, reconstruction, and rehabilitation of three patients with brachial plexus injuries using selective nerve stimulation, muscle transfers, and prosthetic hands. With proper pre-operative training, the patients experienced improved functionality over their injured biological hand, including regaining some gross motor control., These encouraging results pave the way for innovative use of existing technology and future advancements in the field of functional prostheses.
In addition to research efforts, private companies are also helping advance the quality of prostheses. One such company, Limbitless Solutions, is utilizing 3D printing to create simple, affordable, and custom designed prostheses quickly. There is also work being done on creating brain interfaces that can control prostheses directly, overcoming speech and hearing deficits, and the invention of intraosseous transcutaneous amputation prosthesis might someday allow for direct interaction between native soft tissue and prosthetic hard tissue to result in improved functioning. Many of these developments have been made possible by innovations in materials sciences, robotics, and a better understanding of human anatomy and physiology, and it will be exciting to see how the field continues to evolve.