MID-TERM RESULTS OF CEMENTED VERSUS CEMENTLESS TOTAL KNEE ARTHROPLASTY OF THE SAME DESIGN

The attention to biologic fixation has been growing over the past few years in total knee arthroplasty (TKA), due to the evolution of highly porous metals and improved implant designs. The aim of this study was to assess the mid-term survivorship of a modern cementless TKA design, as compared to its cemented counterpart. We reviewed all primary TKAs that were performed at our institution between May 2018 and May 2019. Demographics as age, gender, BMI, ASA were documented. The type of implants used (cruciate-retaining, posterior-stabilized), the fixation technique (cemented, cementless) and the operative time were recoded. We compared the aseptic revision, the all-cause revision and the radiographic outcomes between cemented and cementless TKAs, at a minimum follow-up of 5 years. We identified 300 cemented and 249 cementless TKAs that were performed with the same implant design (Triathlon, Stryker Inc., Mahwah, NJ). The mean operative time was significantly shorter in the cementless group (51.7 min vs 57.9 min, p 0.05). We found non-progressive radiolucent lines (0.05), but there was no radiographic evidence of component subsidence or loosening in either of the groups. The mean follow-up was 5.8 years (range, 5–6.4 years). Cementless fixation in TKA demonstrates excellent mid-term survivorship and radiographic outcomes; equivalent to those of cemented fixation. Longer-term follow-up is warranted, to further assess the durability of cementless implants and explore potential superiority of any of the fixation techniques.