Perioperative Outcomes Using a Second Generation Tapered Femoral Stem versus Dual Tapered Femoral Stem

Background: We present perioperative outcomes using using a cementless , second generation tapered, proximally coated femoral stem (Fiber Metal Taper (FMT) Zimmer, Warsaw, IN) vs. using a cementless dual tapered femoral stem , Avenir(zimmer).

Material and Methods: Between 2009 and 2012 a total of 626 primary hip replacement were performed for primary OA patients using second generation tapered femoral stem . Between 2013 to 2014 a total of 205 primary hip replacement were performed for primary OA patients using dual tapered femoral stem. We retrospectively reviewed the patients, early outcome measures: implant subsidence, intra-operative femur fractures. Radiographic analysis was comprised of pre op x-rays, immediate and 6 weeks post op x-rays. We measured subsidence using trauma Cad software.

Results: A cementless , second generation tapered, proximally coated femoral stem (Fiber Metal Taper (FMT) was used in 626 patients for primary OA. Intra-operative femur fractures occurred in 8 cases (1.28 percent). Early subsidence (more than 3 mm) at 6 weeks occurred in 21 cases (3.35 percent). Cementless dual tapered femoral stem was used in 205 patients for primary OA. Intra-operative femur fractures occurred in one case (0.49%). Early subsidence (more than 3 mm) at 6 weeks occurred in 9 cases (4.39%).

Conclusion: Good clinical results in hip arthroplasty can be obtained using both of them. Intraoperative femur fractures was relatively higher in the second generation tapered group and increased with age and diminished bone quality. Subsidence was similar in both designs.Cementless dual tapered femoral stem offers better matching to more femora with less intraoperative fractures.