Tibial Plateau Coverage in total knee Replacement arthroplasty

ABSTRACT

Maximizing tibial coverage is an important consideration in total knee replacement arthroplasty to provide stability and even load transfer and to improve long term survival rate of the implants. We evaluated the coverage, underhang and overhang ratio for the proximal tibial resection surface during total knee replacement arthroplasty in Koreans. After cutting the proximal tibia, the outline of tibial resection surface was traced manually. We compared 5 tibial tray designs, AGC(Biomet, Warsaw, U.S.A.), Advantim(Wright medical technology, Arlington, U.S.A.), AMK(DePuy, Warsaw, U.S.A), MG II(Zimmer, Indiana, U.S.A.), Series 7000(Osteonics, New Jersey, U.S.A.), which have been commercially used in Korea for total knee replacement arthroplasty. The average percentage of coverage area were 83.3% in AGC, 81.6% in AMK, 80.3% in MG II, 80.2% in Advantim and 76.9% in Series 7000. The average percentage of underhang were 16.7% in AGC, 18.4% in AMK, 19.6% in MG II, 19.8% in Advantim and 23,1% in Series 7000. The average percentage of overhang were measured 7.97% in AGC, 7.86% in AMK, 8.01% in MG II, 8.77% in Advantim and 10.14% in Series 7000. So average coverage percentage of tibial cutting surface was 80.5% in Koreans. The factors which affect the optimal coverage, were the shape, dimensional interval of tibial trays and the number of practically useful tibial trays for Koreans.