INTERPRETATION There was a clinical ly relevant association between early migration of TKPs and late revision for loosening .
PURPOSE We performed two parallel systematic review s and meta-analyses to determine the association between early migration of tibial components and late aseptic revision .
Mobile Bearings Do Not Improve Fixation in Cemented Total Knee Arthroplasty
Mobile bearings were introduced to improve wear and knee kinematics . By uncoupling the forces generated at the articulation from the implant-bone interface this would , theoretically , also improve the fixation of the implant to bone . We did this study to evaluate whether mobile bearings  improve the fixation of the tibial component to bone .  Fifty-two consecutive knees in 47 patients ( average age , 72 years ; range , 62 - 84 years ) with primary osteoarthrosis were r and omized into two groups to receive a cemented total knee arthroplasty with either a fixed-bearing or mobile-bearing tibial component . The quality of fixation was analyzed with radiostereometric analysis for up to 2 years . Mobile bearings did not improve fixation . Both magnitudes and directions of component rotations were similar , and the number of implants with continuous migration was almost identical . Both implant types had a combination of subsidence and lift-off , but where the mobile bearing implants displayed more of subsidence , the fixed bearing knees showed more lift-off . It might be that the somewhat stiffer cobalt-chromium baseplate or the different joint conformity used in the mobile-bearing knees counteracts any potential effects of the mobile bearing . Level of Evidence : Therapeutic Level I. See the Guidelines for Authors for a complete description of levels of evidence
INTERPRETATION There was a clinical ly relevant association between early migration of TKPs and late revision for loosening .
PURPOSE We performed two parallel systematic review s and meta-analyses to determine the association between early migration of tibial components and late aseptic revision .