Revision knee replacement is a challenging procedure that will become more commonplace, as the number of failed total knee arthroplasty (TKA) cases predictably accompany the expected growth of primary TKAs. Implant choice is only one of many variables surgeons must decide on when performing revision TKA (1). The trial conducted by Raymond Kim and colleagues on Midterm Clinical and radiographic results of mobile-bearing revision TKA was very well written, with average 5-year and minimum 2-year follow up. A proposed advantage of mobile bearing revision TKA is possible decreased implant fixation stresses, leading to decreased rates of aseptic loosening when compared to fixed bearing devices (2). Secondly, mobile bearing devices may decrease polyethylene wear and the authors propose that this is particularly important in constrained revision implants. Level of constraint in revision TKA is debatable, with good to excellent results in the literature for both fixed bearing and constrained implants (3-7). The results presented in this paper on mobile bearing revision TKA are quite comparable to those of contemporary revision TKA with fixed bearings. These results offer no clear advantage at the present time compared to fixed bearing designs. This paper should be commended as being the first published series on mobile bearing revision TKA. While the proposed advantages of such implants was not demonstrated in this series, perhaps longer follow up and a comparator group including fixed bearing implants may help further elucidate these issues. Presently, the increased cost of these implants cannot be justified.
Conflicts of Interest: The authors have no conflicts of interest to declare.
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Cite this article as: Kissin YD, Kelly MA. Commentary on “Midterm clinical and radiographic results of mobile bearing revision total knee arthroplasty”. Ann Joint 2017;2:22.