Electronic Thesis and Dissertation Repository


Master of Engineering Science


Biomedical Engineering


Dr. James Johnson

2nd Supervisor

Dr. George Athwal

Joint Supervisor


In patients with debilitating pain due to osteoarthritis, total shoulder arthroplasty can restore function and provide effective pain relief. Newer implant designs vary in length and material stiffness. Unfortunately, literature on these newer implants is limited. This thesis investigates the effect of stem length and implant material stiffness on proximal humeral bone stresses. 3D bone models with implants of various stem lengths (stemless, short, and standard) and different material stiffness’s (CoCr, Ti and PEEK) were generated using MIMICS, Solidworks and ABAQUS for varying abduction angles (15°, 45° and 75°). Cortical and trabecular stresses were contrasted with the intact bone state. As expected, the reduction in stem length and material stiffness yielded humeral stresses that better matched the intact stress distribution in cortical bone, but opposing trends presented in trabecular bone. Future work should continue to build on these models and investigate implant fixation through the analysis of micromotion.