Tibial component fixation in porous- and hydroxyapatite-coated total knee arthroplasty - A radiostereometric evaluation of migration and inducible displacement after 5 years

A total of 51 knees (45 patients) with osteoarthrosis were stratified in a randomized study to receive a hydroxyapatite-coated Freeman-Samuelson (FS H A) or a porous-coated Miller-Galante II (MG II) uncemented total knee arthr oplasty. Repeated clinical, radiographic, and radiostereometric analysis (R SA) evaluations of the tibial components were done for 5 years. The clinica l outcome was equal at the 5-year follow-up (mean Hospital for Special Surg ery score, 93). Standard radiographs displayed more zones around the tibial stem in the MG II group. RSA revealed that the FS HA components migrated l ess (smaller maximum total point motion and maximum subsidence) after 5 yea rs and showed less inducible displacements at the 1-year follow-up. The sta bility of the implants obtained is equal to or better than cemented implant s after 5 years.