Total knee arthroplasty (TKA) is an effective treatment for advanced osteoarthritis of the knee. No large and long-term follow-up study has been done about Cedior® prosthesis. The study hypothesis was that 15-year survival for the Cedior™ prosthesis is at least as good as rates reported for other models. A continuous retrospective single-center study included patients managed by Cedior™ TKA with at least 15-year follow-up. The main endpoint was prosthesis survival; secondary objectives were to identify factors for implant revision and to assess functional scores at 15 years. In the present series, 15-year all-cause survival for the Cedior® knee prosthesis was 93.03%; comparable to rates in the literature, posterior-stabilized implants showed higher revision rates. No other factors for revision emerged. These findings are comparable with those of the literature.