TIBIAL PLATEAU COVERAGE IN TOTAL KNEE ARTHROPLASTY

Optimizing coverage of the resected tibial plateau is an important con sideration in total knee arthroplasty. The tibial coverage of eight di fferent tibial tray designs was examined in 35 resected tibial specime ns. When no component overlap was permitted, the average tibial covera ge of the different designs ranged from 76.4% to 80.8%. When the compo nent was allowed slight overlap, a ''surgical fit,'' the average cover age ranged from 78.5% to 85.5%. As a group, the six symmetric designs provided more coverage than the two asymmetric designs (p < 0.05). Are as of poor coverage were identified, and different tray geometries wer e compared. Asymmetric tibial components are thought to be more anatom ic in nature and therefore cover the tibial plateau surface more compl etely than symmetric components. The results of this study do not supp ort this, and in fact demonstrate that symmetric components can provid e more coverage when compared with two asymmetric component designs.