"Hip And Knee Prostheses:
An Overview Of Design And Biomechanical Performance Requirements"
Danieli Rodrigues, Fatigue & Fracture Mechanics Research Department, Zimmer Inc.
Joint replacements are intended to provide long-term restoration of function and pain relief. A variety of new designs are currently offered with materials and geometries that better fit patient anatomy and meet the biomechanical requirements of much younger and active patients. Biomechanical testing of medical devices is performed during their development process to simulate the biological environment and loads the implant or instrument will be typically subjected to during clinical use. Biomechanical testing is strictly regulated in the medical device industry to ensure implant safety and efficacy. This talk will discuss some of the testing tools currently used in the industry for evaluation of total hip and knee implants and surgical instruments performance. Particularly, it will address how important biomechanical information is derived from in vitro cadaver testing and model simulation for test development.
Additionally, current problems associated with modular designs of hip and knee implants and research opportunities in the field will be addressed. Challenges typically associated with implant failure include: fretting crevice corrosion, polyethylene wear, bone cement failure, mechanical loosening, fatigue failure, pain, infection, and osteolysis. Understanding the dynamic loads imposed on the joints during daily activities provides critical information for addressing these clinical problems still prevalent in modern arthroplasty. Novel testing methods that more realistically mimic the in vivo environment can greatly contribute for a better evaluation of implant performance, ultimately enabling the development of devices with lower probability of failure.
Danieli Rodrigues received her BS Degree in Chemical Engineering from Universidade Federal de Santa Maria, Brazil in 2005. She then joined the Department of Biomedical and Chemical Engineering at Syracuse University, Syracuse – NY, receiving her MS in 2007 and PhD in 2010. Her graduate studies focused on Orthopeadic research, primarily working on the characterization of corrosion and failure mechanisms of retrieved modular hip implants, and development of acrylic two-solution bone cements for the treatment of spinal compression fractures. Danieli is currently a Senior Research Engineer in the Fatigue and Fracture Mechanics Research Department at Zimmer Inc, Warsaw – IN. Her current activities with the medical device industry are related to test method development for validation of novel designs of hip and knee implants and surgical instrumentation.