Mechanical design and numerical analysis of a femorotibial implant in patients with medial knee osteoarthritis

Medial knee osteoarthritis (OA) is a progressive and degenerative disease characterized by a gradual and progressive destruction of the cartilage that covers the articular surface. OA has increased dramatically in recent years, mainly among young people basically due to sports injuries and overweight. It is one of the leading causes of the musculoskeletal pain and disability in adulthood. For those cases in which the damage at the medial knee zone with a slight to moderate articular wear, it has been proposed a femorotibial implant design which should stop the progression of the degenerative process and alleviate the pain without altering the anatomy and biomechanics of the knee joint. This study is made through computational programs, using the Finite Element Method (FEM), for modeling a three-dimensional assembly which is applied to analyze an implant with a mechanical function and the behavior of the device is studied. Once the femorotibial implant is designed and modeled, a structural numerical lineal-elastic analysis through FEM was made, with the objective to determine the total displacements, as well as, the stress field on the materials. A suitable device was obtained which produced very good results for the safety factor obtained from the stress analysis of the pieces. Finally, it is expected the patient is to be able to carry on his daily activities without pain and improving the quality of life.