The influence of tibial tray design on the wear of fixed-bearing total knee replacements.
Debris-induced osteolysis due to surface wear is a potential long-term problem in total knee replacements (TKRs). Wear between the tibial tray and ultra-high molecular weight polyethylene insert is thought to contribute to the wear. This study investigated the influence of tibial tray design on the wear of fixed-bearing TKRs. Specifically, this study investigated the influence of the material's surface finish and design characteristics of the locking mechanism of the tibial tray on the wear in fixed-bearing knees for both cruciate-retaining (CR) and posterior-stabilized designs. A new fixed-bearing tibial tray design using Co-Cr and with an improved locking mechanism significantly reduced polyethylene wear from 22.8 +/- 6.0 mm3 per 10(6) cycles to 15.9 +/- 2.9 mm3 per 10(6) cycles compared with a previous titanium alloy tray with a CR design. The wear rates were similar to those of a fixed-bearing insert clamped into a tibial tray, suggesting that the decrease in wear was due to a reduction in backside wear. There was no significant difference between the wear rates of a cruciate-retaining design and a posterior-stabilized design under the two kinematic conditions tested.
Galvin
A
A
Institute of Medical and Biological Engineering, School of Mechanical Engineering, University of Leeds, Leeds, UK. a.l.galvin@leeds.ac.uk
Jennings
L M
LM
McEwen
H M
HM
Fisher
J
J
D019544:Equipment Failure Analysis; D017276:Friction; D007720:Knee Prosthesis; D011474:Prosthesis Design; D013314:Stress, Mechanical; D014800:Vitallium / Q000737:chemistry*
D014800:Vitallium