Biomedical Engineering Reference
In-Depth Information
performed annually, and the future incidence is expected to increase as the
population ages and maintains its activity and function level (Crowninshield et
al., 2006).
The standard bearing coupling in THA and TKA today consists of a cobalt±
chromium (CoCr) alloy articulating against UHMWPE (Fig. 7.1). After 10±15
years in vivo, UHMWPE wear particles lead to localized inflammation in the hip
joint, periprosthetic bone resorption and, ultimately, aseptic loosening of the
7.1 (a) Prosthetic hip implants with CoCr±UHMWPE bearing couple (top),
and Al
2
O
3
±Al
2
O
3
bearing couple (bottom). (b) Prosthetic knee implants with
stabilized ZrO
2
±UHMWPE bearing couple (left) and CoCr±UHMWPE bearing
couple (right).
