Abstract
The initial application of bone ingrowth technology to the fixation of total knee arthroplasty (TKA) components without bone cement was based on the premise that bone cement was “not biologic”, and so over time would undergo fatigue failure with subsequent loosening. It was hoped that this problem could be obviated by cementless fixation by bone ingrowth, which would remodel over time and not fatigue. In addition, it was anticipated that the failed cementless TKA might be easier to revise and leave the surgeon with more bone to work with. Whether or not cementless fixation of TKA components was justified on any of these counts was uncertain through the first 2 decades of their use. Much of the data accumulated during that period poorly supported these contentions, while cemented TKA was increasingly reported as a reliable, consistent and less complicated form of TKA fixation. However, over the past decade, new evidence has accumulated demonstrating greater success with this technology in several well designed studies as well as from registry studies. Most of this evidence involves the use of Porous Tantalum. However, increasing evidence that loosening of well done, well designed cemented TKA is rare along with some evidence that a certain percentage of cementless TKA patients fail to achieve stability remains concerning. In addition, no studies have justified improved longevity to the extent that the increased cost of cementless devices can be justified.
