The association of (polyethylene) insert thickness in primary total knee arthroplasty and the risk of revision. A Dutch arthroplasty register study.
Approval date: September 26th 2025
Starting date: Oktober 20th 2025
Dr. R.C.I. van Geenen, Dr. S.B.T. Bolder, Drs. I. Koenraadt-van Oost, Dr. A. Nijs
Research proposal abstract
Frequently registered reasons for revision in total knee arthroplasty (TKA) are loosening, instability and wear. These reasons can be related to the polyethylene (PE) insert used. The thickness of the PE insert used depends on perioperative findings such as the amount of proximal tibia or distal femur resection, soft tissue laxity and ligament releases. In literature there are contradictory results on survival of a TKA regarding the thickness of the PE insert. A well-balanced TKA is the golden standard, however the optimal PE insert thickness is unknown.
In this study we will evaluate whether PE insert thickness is associated with the survival in TKA. Our hypothesis is that thick PE inserts are associated with higher revision rates due to wear, loosening and instability.
We will use data from the LROI database to compare thin and thick PE inserts in TKA and the overall risk of revision and reasons for revision to determine survival rates. Kaplan Meier survival curves and Cox proportional hazards regression analysis will be used to compare the risk of revision. Sub-analyses will be carried out for reasons for revision caused by loosening, instability and wear. Moreover, we will examine type of used PE insert.