The alignment of transfemoral prostheses is a critical process for ensuring patient mobility and comfort, but currently employed devices present significant limitations. The latter offer limited and fixed degrees of freedom, while the fitting process is time-consuming, costly, and error-prone, often requiring later correction. To address these challenges, this thesis presents an innovative system for transfemoral prosthesis realignment, inspired by the adjustable bicycle saddle mechanism. The project followed a structured design process, starting with freehand sketches and morphological analysis, followed by CAD modeling in SOLIDWORKS. The structural integrity of the final design was validated using the Finite Element Method (FEM) in COMSOL Multiphysics.