QL+ Engineering Students from Colorado School of Mines were challenged to design and create “soft socket shorties” to improve the quality of life of a QL+ Challenger and Army Veteran named Jeremy. Jeremy has been on nine deployments overseas. After safely returning from deployment, Jeremy was hit by a drunk driver in his driveway while loading his truck for a fishing trip. Jeremy is now a bilateral above-the-knee double amputee.
The Challenge is to create comfortable soft socket shorties for him to use in the home and outdoors. Soft socket shorties are like slippers for bilateral above-the-knee amputees, that give them a lower center of gravity. A successful design of more comfortable shorties will allow Jeremy to achieve maximum comfort in his home and outdoors. Shorties are usually more comfortable than full prosthetic legs but can still be hot and uncomfortable if worn for long periods of time.
The primary objective of this Challenge is to provide a comfortable/flexible socket that will be breathable, waterproof, and usable for extended durations indoors and outdoors. The shorties will also allow Jeremy to transition from swimming to biking without the assistance of another person. In addition to being able to go from water to bike, the design will allow him to transition from indoors to harsh, outdoor terrain including sand, grass, pavement, and gravel.
The final design consisted of subischial sockets with soft inner shells made from silicon, a copolymer outer shell in the shape of a c-clamp with a cap, and tread attached directly to the cap. The c-clamp can be adjusted using the ratchet straps. The c-clamp shape allows for the containment of the tissue while minimizing the amount of copolymer used making the socket more comfortable than previous designs. A cap on the distal end of the socket takes advantage of the geometry of Jeremy’s residual limb by hooking on the epicondyles, providing additional securement of the socket. The inner silicone layer offers comfort and suction to keep the socket on his leg while in the water. Furthermore, a subischial socket design makes this socket cooler and more breathable than previous models, as it does not cover as much of the residual limb as other socket designs. Also, the subischial design adds comfort as it does not contact the ischial tuberosities of the client, which can cause irritation and discomfort over long periods of time. Finally, the tread attached to the distal end of the socket in a half sphere shape allows the client to grip when turning or on uneven surfaces.
The final design was hugely successful. It answered all of Jeremy’s wants and needs, and he was satisfied. The sockets remained secure in the water and they were buoyant, which will help if they ever fall off while he is swimming.
This team won first place at the Colorado School of Mines College of Engineering and Computational Sciences Capstone Design Showcase in the Best of Societal Impact/Human Systems Category! We are very proud of their work!