Survival analysis of primary cemented total knee arthroplasty: which designs last?

Both posterior stabilization and metal backing of the tibial component are design changes that could alter the longevity of total knee arthroplasties (TKAs). Survival analysis data from 16 articles (5,950 knees) were combined to compare design features. No difference was found in survival between posterior stabilized implants and implants that were not stabilized or between metal-backed and all-polyethylene tibial components. Those all-polyethylene tibial components that were not stabilized showed significantly better survival than metal-backed, nonstabilized tibial components and posterior stabilized, metal-backed components (P<.05) but not posterior stabilized, all-polyethylene components. According to the currently available literature, posterior stabilization or metal backing of the tibial component does not improve the longevity of primary cemented fixed bearing condylar-type TKAs.