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.