A 13- to 16-year clinical and radiological outcome study of the genesis II cruciate retaining total knee arthroplasty with an oxidised zirconium femoral component.

Purpose: The Genesis II Total Knee Arthroplasty with an oxidized zirconium (OxiniumTM) femoral component (Smith & Nephew, Memphis, TN, USA) was introduced in an attempt to reduce polyethylene wear and osteolysis.

Methods: We retrospectively evaluated prospectively collected data from 245 consecutive patients (40 men and 205 women; mean age at surgery 70.1 years, range 44 to 85 years) who underwent 261 TKAs with a mean follow-up of 15.1 years (range 13 to 16 years). Implant failure rate, complication rate, clinical (both subjective and objective) and radiological outcomes were assessed.

Results: At final follow-up, 24 (9.8 %) patients (24 TKAs) were lost to follow-up and 35 (14.3%) patients (35 TKAs) had died for reasons unrelated to surgery. Four TKAs, in four patients, were revised because of aseptic loosening. In five TKAs (five patients) secondary patella resurfacing was performed because of patellofemoral pain. Survivorship analysis showed a cumulative success rate of 98.4% (95% CI, 94.3% - 100%) at 15 years with revision for aseptic loosening as an end point, and 95.6% (95% CI, 92.7% - 98.7%) at 15 years with revision for any reason as an end point. All patients showed a statistically significant improvement (p = 0.01) in the Knee Society clinical rating system, WOMAC Score, KOOS Score, Oxford Knee Score and EuroQol 5D Score. Surgery fulfilled patient expectations for 90.1% of patients; in 5.4% it did not, and 4.5% declined to answer.

Conclusion: This study demonstrates satisfactory long-term clinical results for this knee design.