Biomechanical evaluation of load-bearing performance and primary stability in a novel transhumeral osseointegrated prosthesis: a finite element analysis

After humeral amputation, patients often struggle to handle medium to heavy loads. Conventional hollow socket prostheses remain insufficient for such demands. This study proposes an innovative transhumeral osseointegrated prosthesis design, evaluated using a three-dimensional finite element model under five static loads (25-300 N) with Bio-steel and Ti-6Al-4V implants. Stresses in cancellous bone remained well below compressive strength limits (≤1.11 MPa), even at maximum loading. Implant displacements were minimal (<0.63 mm), indicating high primary stability. These results confirm the model's mechanical validity and support this prosthesis as a safe and effective load-bearing alternative for upper-limb amputees.