First experiences with knee prostheses with a tibial component made of trabecular tantalum

Abstract

Background: Although excellent log-term results have been reported with cemented tibial fi xation, means to improve the longevity of total knee replacements continue to be of interest to clinicians. Based on good results obtained for hip prostheses, one of the possible choices is the use of cementless fi xation with improved eff ectiveness of osseointegration. Tibial components made of trabecular metal introduced recently have off ered greatly increased bone ingrowth and good functional characteristics due to their porous structure and physical-chemical properties similar to those of bone. Monoblock design prevents the back-side wear. Methods: We have implanted 434 total knee replacements with tibial components made of trabecular tantal (Trabecular Metal Monobloc, Nexgen Legacy). Patient demographic data were analysed and revision cases were described. Results: Aft er a mean follow-up of 28 months fi ve components were revised: three for infection, one for instability and one for rigidity. Conclusions: Cementless knee prosthesis made of trabecular tantalum has the advantage of shorter operation time and avoidance of possible adverse eff ects of cement as well as its deterioration and delamination. With increasing follow-up period we expect longterm advantages in terms of improved direct osseointegration. Disadvantages are the relatively high price of the prosthesis and the possibility of a potentially higher incidence of infection due to the lack of antibiotics from the cement.