A bionic knee restores natural movement

In a small clinical study, people with above-the-knee amputations said it helped them navigate more easily and felt more like part of their body. A subject with the osseointegrated mechanoneural prosthesis overcomes an obstacle placed in their walking path by volitionally flexing and extending their phantom knee joint. Control signals from their residual knee muscles are used to produce movement of the powered prosthetic knee that mirrors the phantom knee. MIT researchers have developed a new bionic knee that is integrated directly with the user's muscle and bone tissue. It can help people with above-the-knee amputations walk faster, climb stairs, and avoid obstacles more easily than they could with a traditional prosthesis, which is attached to the residual limb by means of a socket and can be uncomfortable. For several years, Hugh Herr, SM '93, co-director of the K. Lisa Yang Center for Bionics, has been working with his colleagues on techniques that can extract neural information from muscles left behind after an amputation and use that information to help guide a prosthetic limb.