A study by researchers from Northwestern University (Evanston, Illinois, United States), Rush University Medical Center, (Chicago, Illinois, United States) and the University of Duisburg-Essen (Germany) found that a layer of graphitic carbon forms on metal-on-metal hip implants. The discovery could eventually improve the performance of these types of implants, since the layer reduces friction, wear and corrosion.
Previous research by Alfons Fischer at the University of Duisburg-Essen and Markus Wimmer at Rush University Medical Center found that a lubricating layer forms on metallic joints as a result of friction. The researchers did not know what the layer was, but assumed it was made of proteins that adhered to the implant’s surfaces. Building on the research, an interdisciplinary team studied several implants that had been retrieved from patients for various reasons. They determined that the layer consists primarily of graphitic carbon.
The failure rates of current prosthetic materials, including metal, typically increase after 10 years, since the materials are susceptible to the joint’s wear and tear. The findings could be used to improve the performance of metal-on-metal implants by manipulating the system to produce graphitic carbon, according to Alfons Fischer.Camilla Andersson