A Comprehensive Analysis of Balance, Symmetry, and Center of Mass in the Gait Cycle of Transfemoral Amputees

Abstract

The purpose of this thesis is to create a framework that assists in the transfemoral prosthesis fitting process by calculating balance and symmetry to quantify patient comfort with an understanding of bipedal locomotion and human anatomy. Three different software applications were used to compare (1) the body position during gait cycle, (2) the natural and amputee anatomies, (3) the natural and prosthetic legs, and (4) the equilibrium and torque movements of the hip, knee, and ankle joints. Models were created in Maya for analysis in Solidworks and MEL code evaluation with MatLab. The MatLab code tested combinations of joint degrees and identified stability leg rotations. Additionally, the center of mass (COM) analysis demonstrated that the 3rd combination of materials for the prosthetic leg proved to be closest in COM position to the natural leg (COMNL ratio = 0.6241) with a COM ratio = 0.5972. COM determination assists in establishing symmetry in the prosthesis and amputee relationship. The (COM) alteration contributors were established as the stump length, prosthesis weight, and body position and anatomy