The incidence of modular tibial polyethylene insert exchange in total knee arthroplasty when polyethylene failure occurs.

One of the primary reasons for utilizing modular tibial polyethylene inserts (MTPI) at the time of total knee arthroplasty is to have the ability to simply exchange the polyethylene at the time of revision surgery when polyethylene failure has occurred. During a 2-year period from January 1993 to December 1994, 62 revision total knee arthroplasties were reviewed from five different institutions in North America, which were performed secondary to modular tibial insert failure. In 55 cases (88.7%), significant scoring and/or damage to the femoral and/or tibial components occurred necessitating revision of one or both components. This series does not support the premise that polyethylene exchange is common at the time of revision surgery for MTPI failure. Of the patients 88.7% had MTPI failure resulted in femoral and/or tibial component revision secondary to surface damage to the femoral component and/or tibial component baseplate. In order to avoid femoral and tibial component wear secondary to MTPI failure, early recognition is necessary to allow the much simpler operation consisting of polyethylene liner exchange only.