Revised Leg prosthesis - Below the Knee

thingiverse

Based originally on the excellent design by Agung Dwi Junianto, Department of Industrial Design, ITS Surabaya, Indonesia. Advisor: Djoko Kuswanto, ST., M.Biotech. 10/15/18: These are revised files for a leg with all printed parts except support post (1" OD aluminum) and hardware. All parts printed in either PETG (leg socket) or Carbon Fiber PETG or CF Nylon (foot and ankle piece) to provide the necessary strength and resilience. This new version is loosely based on an MIT design that utilized a shorter foot with a small degree of flexibility that provides a much more natural gait when properly fitted. The foot should be given a sole of non-slip rubber so it can be worn either barefoot or inside of a shoe. Further size specific foot pads can be made to fit much larger shoes if needed but the present design can be accommodated by a large number of sizes as is. This is an untested experimental design and should be treated as such. That said, all tests I have accomplished to date indicate the necessary strength and resilience is effectively present in well-printed parts. Real world testing is needed to check viability. 2/15/19 AS PUBLISHED THIS IS AN IMMATURE DESIGN. There is no way to effectively attach the device to a leg. I am working on two variations to accomplish this. One is by using two-part polyurethane (quick set) and actually using the patient's leg, plastic wrapped and covered with mold release, to form an accurate socket for the remaining limb. In addition, the re-designed prosthetic will incorporate an external knee brace from prosthetic to thigh. You will have to measure and adjust the socket end to fit the patient. Include extra room for a prosthetic sock on the limb as well. There are many considerations when fitting a leg and to avoid complications, the health of both patient and his/her remaining limb should be carefully assessed. Diabetics may have circulation problems. Any improperly healed or open lesions need to be fully healed before fitting. The remaining limb should evidence absolutely no swelling or inflammation. Finally, the construction materials of both foot pad and upper socket are critical to assure the needed strength of a 3d printed leg. I use a carbon fiber/nylon composite filament for the foot pad and PETG for the socket. Both have a high density of infill and a number of walls for strength. Any device should be tested thoroughly before fitting to assure the greatest possible structural integrity. There are other possibilities for the device to limb attachment which you, as maker, need to determine will be best in your case. No matter what, your expertise in design, building, and fitting the device will all be tested. Feedback Encouraged!