College - Author 1
College of Engineering
Department - Author 1
Biomedical Engineering Department
Degree Name - Author 1
BS in Biomedical Engineering
College - Author 2
College of Engineering
Department - Author 2
Biomedical Engineering Department
Degree - Author 2
BS in Biomedical Engineering
College - Author 3
College of Engineering
Department - Author 3
Biomedical Engineering Department
Degree - Author 3
BS in Biomedical Engineering
Date
3-2026
Primary Advisor
Soph Ziemian, College of Engineering, Biomedical Engineering Department
Additional Advisors
Christopher Heylman, College of Engineering, Biomedical Engineering Department
Abstract/Summary
This project presents the design, development, and evaluation of a Total Knee Arthroplasty (TKA) Antibiotic Spacer Augment Tool intended to improve the reproducibility and efficiency of cement augment creation during two-stage revision surgeries for periprosthetic joint infection. Currently, cement augments are often shaped manually during surgery, which requires significant surgeon expertise and can lead to inconsistent geometries. To address this limitation, a modular jig system was designed to mold antibiotic-laden bone cement onto tibial and femoral spacer implants with controlled geometry and thickness increments. The design process included customer requirement analysis, engineering specification development, concept generation, and concept evaluation using Pugh matrices, followed by CAD conceptual modeling and risk analysis through failure mode and effects analysis (FMEA) and a design hazard checklist. The final device integrates reusable aluminum structural components with silicone molds that conform to implant geometry while preventing cement leakage and ensuring accurate augment thickness. Manufacturing involved waterjet machining for metal components and 3D-printed molds for silicone casting. Validation testing included cement characterization, thermal testing of cement polymerization, simulated use and dimensional accuracy testing, and human factors evaluation. Results demonstrated that the device produced cement augments within ±0.5 mm dimensional accuracy, prevented cement leakage, and allowed assembly and disassembly within required time constraints, indicating that the jig is an effective and practical tool for improving the reproducibility and usability of cement augment fabrication during TKA revision procedures.
URL: https://digitalcommons.calpoly.edu/bmedsp/212