In vitro wear simulation on the RandomPOD wear testing system as a screening method for bearing materials intended for total knee arthroplasty

JOURNAL OF BIOMECHANICS

卷:47

Article

Saikko, Vesa

关键词: Non-cyclic;    Wear simulation;    Polyethylene;    Total knee replacement;    Contact mechanics;   

DOI  :  10.1016/j.jbiomech.2014.04.039

来源: Elsevier

【 摘 要 】

The 16-station RandomPOD wear test system, previously validated for prosthetic hip wear, was used in the simulation of knee wear mechanisms with a ball-on-flat test configuration. This consisted of a CoCr pin with a ground and polished spherical bearing surface (radius 28 mm) against a conventional, gamma-sterilized UHMWPE disk in serum lubrication. The biaxial motion, consisting of x and y translations, and the load was non-cyclic. Relative to the disk, the center of contact wandered within a circle of 10 mm diameter, and the average sliding velocity was 15.5 mm/s (ranging from 0 to 31 mm/s). The load varied non-cyclically between 0 and 142 N (average 73 N). In the 60-day test with 16 similar wear couples, moderate adhesive wear, the principal wear mechanism of a well-functioning prosthetic knee, dominated. This showed as a burnished, circular wear mark (diameter 13.2 mm, area 137 mm(2)). The wear factor was 2.04 +/- 0.03 x 10(-6) mm(3)/N m (mean +/- 95 percent confidence limit). For the first time a truly multidirectional, realistic and uniform, large capacity pin-on-disk simulation of knee wear mechanisms was implemented. (C) 2014 Elsevier Ltd. All rights reserved.

【 授权许可】

Free