Failures in Metal-on-Metal Modular Hip Implant Components

Failures in Metal-on-Metal Modular Hip Implant Components

by Emily Mitchell, M.S., Bastiaan Cornelissen, Ph.D., P.E.

Multiple failures investigated in a recalled metal-on-metal (MOM) modular hip implant system were caused by fatigue fracture initiated by mechanically assisted corrosion (MAC) and/or periprosthetic osteolysis. While MOM modular hip implant systems are no longer recommended for primary total hip arthroplasties, the lessons learned from their use have influenced the ongoing design and development of modern implants. The interplay of implant design, material choice, and patient factors related to these failures will be discussed in addition to investigation techniques used to determine the failure mode.