Partial resection of the PCL insertion site during tibial preparation in cruciate-retaining TKA.

Abstract

Based on the anatomy of the tibial PCL insertion site, we hypothesized that at least part of it is damaged while performing a standard tibial cut in a PCL-retaining total knee replacement. The purpose of this study was to determine and quantify the amount of resection of the tibial PCL attachment with a 9 mm tibial cut with 3 degrees of posterior slope. Twenty cadaver tibias were used. The borders of the PCL footprint were demarcated, and calibrated digital pictures were taken in order to determine the surface area. A standard tibial intramedullary guide was used to prepare and perform a tibial cut at a depth of 9 mm with 3 degrees posterior slope. After the tibial cut was made, a second digital picture was taken using the same methodology to measure the surface area of the remaining PCL insertion. The mean surface area of the intact tibial PCL footprint before the cut was 148.9 ± 25.8 mm(2) and after the tibial cut 47.1 ± 28.0 mm(2). On average, 68.8 ± 15.3 % of the surface area of the PCL insertion was removed. The results of this study, therefore, indicate that the conventional technique for tibial preparation in cruciate-retaining total knee arthroplasty can result in damage or removal of a significant part of the tibial PCL insertion.