Scott CEH, et al. - The researchers herein explored the differences in implant requirement, outcomes and re-revision when total knee arthroplasty (TKA) was performed after unicompartmental to total knee arthroplasty (UKAs) with metal-backed (MB) vs all-polyethylene (AP) tibial components. Increased chances of a complex revision requiring tibial stems and cruciate substitution were noted with the metal backed UKA implants. But the chances of early revision were reduced by the metal backed UKA implants compared to all-polyethylene UKA, which often failed early with pain.