40 patients scheduled for total knee arthroplasty were randomized to surgery completed using either patient specific positioning guides (PSPG) or conventional instrumentation (CONV). Patients were followed for 2 years after surgery for maximum total point motion of the tibial component on radiostereometric analysis. At 2 years, only 20 patients were available for analysis. Results demonstrated, that while the difference between groups in MTPM of the tibial component was not significant, mean MTPM from 1 to 2 years increased in the PSPG group versus no marked increase noted in the CONV group.