Abstract
The study was conducted to investigate differences between simultaneous and sequential cementing of the tibial and femoral components in total knee joint replacements. Our hypothesis was that cementing the components sequentially increases accuracy of the final position.
This was a prospective and randomized study, performed using a computer navigation system as the evaluation technique to determine the accuracy of implant positioning. All knee replacements (Scorpio, Stryker) were implanted using navigation technique.
The patients were divided in two groups. The first group had implants cemented simultaneously where the tibial and femoral components were implanted with a single mix of cement and then pressurized by extending the leg.
The second group of patients had the tibial component inserted with the first mix of cement and then impacted. The cement was allowed to set before proceeding with insertion of the femoral component using a second mix of cement.
The computer navigation system was utilized for bone cuts. It was then used to measure 3 sets of angles. The first set was varus/valgus cut of the femur, varus/valgus cut of the tibia and posterior slope of the tibia. The second set of measurements were the same angles, this time of the position of the prosthetic components before cementing, and the third set after cementing.
Our interim results show just a small difference between the two techniques.
It does not appear there is substantial difference in positioning of the implants between these two different techniques.
The abstracts were prepared by Editorial Secretary Jean-Claude Theis. Correspondence should be addressed to NZOA at Department of Orthopaedic Surgery, Dunedin Hospital, Private Bag 1921, Dunedin, New Zealand.
