Extraarticular abrasive wear in cemented and cementless total knee arthroplasty.

In this study, we examine the contributions of periprosthetic impingement to a seldom recognized source of PE damage resulting in gouging, abrasion, and severe localized damage in cemented and cementless total knee replacement. One hundred sixty two tibial components of 34 different designs in a retrieval collection were examined. The presence and location of abrasive wear to the nonarticulating edges of the insert were measured, with representative specimens examined using SEM. Significant abrasive wear was observed in 35% of the retrievals with cemented femoral components and 25% from noncemented components. Within the group of worn inserts, abrasive scars were seen with a frequency of 75% on the extreme medial edge, 20% on the extreme lateral edge, 26% on the posteromedial edge, and 16% on the posterolateral edge. The role of extraarticular impingement in this damage mode was confirmed by examination of retrieved femoral components with overhanging cement or embedded osteophytes. In the majority of cases, this complication may be avoided by careful removal of excess cement and extracortical osteophytes.