50 patients scheduled for total knee arthroplasty were randomized to receive either an uncemented trabecular metal Monoblock tibial component or an uncemented trabecular metal Modular tibial component. The purpose of this study was to compare component migration via radiostereometric analysis between the two groups over the first postoperative year. Data from 41 patients was available at 12-month follow-up. The difference in maximum total point motion of the tibial component between groups did not reach statistical significance but was notably higher in the Modular group compared to the Monoblock group.