Porous trabecular metal cone augments in revision total knee arthroplasty

The management of bone loss in revision total knee arthroplasty (TKA) can be challenging. Defects range in size and significance from shallow, contained cavitary defects that can be satisfactorily managed with a variety of techniques to large bicondylar defects that historically required either large structural bone grafts or prosthetic substitution. The development of large porous-metal cone augments that allow for either bony ingrowth or cement fixation has added a new tool to the armamentarium of the revision TKA surgeon. These cone augments represent an appealing alternative to structural bone grafts in many patients because they allow for early weight bearing and are not at risk for resorption. Early clinical results of revision TKA performed with large porous-metal cone augments have been encouraging. Although long-term follow-up is required, the diversity of large porous-metal augments will likely continue to grow to facilitate intraoperative management of bone defects in revision TKA. In this article, the selection of bone defects that are suitable for use with these augments and the results and complications will be reviewed. Furthermore, a step-by-step approach to the use of these large augments for managing tibial and femoral defects will be described.