Impact of Metaphyseal Sleeves and Porous Cones on Risk Reduction for Revision Total Knee Arthroplasty: Aseptic Re-Revision in a United States Integrated Health Care System.

Abstract

Bone loss in revision total knee arthroplasty (rTKA) makes achieving a well-fixed construct challenging. Metaphyseal sleeves and porous cones were designed to enhance fixation during rTKA and are typically used in combination with modular stems. However, there are limited outcome data comparing rTKA constructs with stems and sleeves or cones to those with stems alone. Therefore, we sought to compare re-revision rates in patients undergoing rTKA with cones/sleeves + stems to those with just stems. We conducted a cohort study from a United States health care system's arthroplasty registry. The study sample included 2,882 aseptic rTKAs that included a stemmed component only (N = 2,264) or a stem and a cone/sleeve (N = 618) (2008 to 2022). Propensity score-weighted Cox proportional hazard regression was used to evaluate the risk of aseptic re-revision and re-revision due to loosening specifically. At 8-year follow-up, after propensity score weighting, no difference was observed between stem + cone/sleeve compared with stem alone for aseptic re-revision (hazard ratio = 0.76, 95% confidence interval = 0.42 to 1.37) or aseptic loosening specifically (hazard ratio = 0.62, 95% confidence interval = 0.27 to 1.43). In a cohort of over 2,500 rTKAs, we found the addition of metaphyseal sleeves or porous cones did not change the risk of aseptic re-revision overall or re-revision due to loosening specifically. Further large-scale studies with long-term follow-up are warranted to confirm these results.