Design and testing of low-cost knee prosthesis

One of the Ecuadorian Government policies leads to the improvement of the quality of life of its population. In that way, most of the universities have been given the task of carrying out investigations needed to comply with these policies. In the Imbabura State, one of each 2,200 inhabitants have a transfemoral amputation. The Technical University of the North is the only institution located in the region with a capacity of technology development. Due to the described above, Mechatronics Engineering and Physiotherapy Schools are a fundamental pillar for development prosthetic devices at low cost, intended for people with low resources to improve their quality of life. A solution modeled and simulated using a CAD/CAE software based on MEF, is proposed. Gait analysis, patient and prosthesis weights and materials sold in the country, are the criteria considered. The prototype is printed in ceramic powder to evaluate the functionality. Using a 3-axes CNC milling (ROMI D 800) and a wire cutter (EDM CHMER) the model is manufactured. A testing of engineering based on prosthesis efficiency, degree of adaptability and resistance of materials, are made. Finally, the device was tested using a patient previously chosen. The results are that a knee prosthesis for transfemoral amputation is obtained for a 900 N weight patient using an appropriate material. The articulation emulates the functional movements of 80 degrees flexion-extension and the patient chosen indicates its satisfaction using the device.