Influence of joint area design on tibial component migration: comparison among a fixed symmetrical, asymmetrical, and moveable bearing.

摘要: Fifty-four knees (50 patients) were allocated to three different tibial polyethylene inserts (standard/rotating platform/FS1000) in the Freeman-Samuelson (Finsbury Orthopaedics Ltd, Surrey, United Kingdom) total knee arthroplasty. The FS1000 design has a spherical medial and roller-in-trough configuration laterally. Radiostereometric examinations done postoperatively after 3, 12, 24 months. median migration of metal-backing Hospital for Special Surgery scores did not differ between groups. At 2 years, external/ internal displacements rotating platforms 2.8 degrees 0.2 degrees, respectively (rotating versus standard inserts/rotating FS1000: P < .0005). Longitudinal rotations above detection limits radiostereometry observed some fixed implants (standard designs), indicating conditions backside wear.