Clinical and Radiographic Evaluation of the OMICRON 2® Total Knee Prosthesis: A Multicenter Study With Long-Term Follow-up

Keywords: Knee arthroplasty, osteoarthritis, OMICRON 2®, survival

Abstract

Introduction: Total knee arthroplasty is the ideal treatment for severe osteoarthritis. The OMICRON 2® system, introduced in Argentina in 2009, incorporated improvements in implant design and instrumentation to optimize and prolong implant survival. Materials and Methods: A retrospective, longitudinal, observational study included 1,346 total knee arthroplasties performed between 2009 and 2024 at three hospitals in the province of Buenos Aires. Complete clinical and radiographic follow-up data are presented for 616 patients. The Knee Society Score (KSS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were used to assess function over time, together with standardized radiographs. Implant survival was defined as retention of the implant without revision and was assessed using Kaplan-Meier curves. Results: The mean age was 71.6 years. The most common diagnosis was primary knee osteoarthritis (86%). Implant survival at 15 years was 92.4%. The KSS improved from 37.5 preoperatively to 85.1 at 15 years, and the WOMAC score improved from 89.2 to 15.5 over the same period. At the end of follow-up, 89.8% of patients had no signs of loosening, and only 2% showed minimal femoral changes. Complications included infections (2.7%), septic loosening, periprosthetic fractures, and instability. Conclusion: The OMICRON 2® system demonstrated good clinical and radiographic performance, with high long-term implant survival, and is a reliable option for total knee arthroplasty.

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Author Biographies

Carlos Vega, Knee Unit, Hospital Municipal Central de San Isidro “Dr. Melchor Á. Posse“, Buenos Aires, Argentina; Hip and Knee Unit, Hospital Zonal de Agudos “Dr. Carlos A. Bocalandro“, Buenos Aires, Argentina
Knee Unit, Hospital Municipal Central de San Isidro “Dr. Melchor Á. Posse“, Buenos Aires, Argentina Hip and Knee Unit, Hospital Zonal de Agudos “Dr. Carlos A. Bocalandro“, Buenos Aires, Argentina
Favio Moruno, Knee Unit, Hospital Municipal Central de San Isidro “Dr. Melchor Á. Posse“, Buenos Aires, Argentina; Hip and Knee Unit, Hospital Zonal de Agudos “Dr. Carlos A. Bocalandro“, Buenos Aires, Argentina
Knee Unit, Hospital Municipal Central de San Isidro “Dr. Melchor Á. Posse“, Buenos Aires, Argentina  Hip and Knee Unit, Hospital Zonal de Agudos “Dr. Carlos A. Bocalandro“, Buenos Aires, Argentina
Javier Megey, Knee Unit, Hospital Municipal Central de San Isidro “Dr. Melchor Á. Posse“, Buenos Aires, Argentina
Knee Unit, Hospital Municipal Central de San Isidro “Dr. Melchor Á. Posse“, Buenos Aires, Argentina
Wilmer Jimenez, Knee Unit, Hospital Municipal Central de San Isidro “Dr. Melchor Á. Posse“, Buenos Aires, Argentina
Knee Unit, Hospital Municipal Central de San Isidro “Dr. Melchor Á. Posse“, Buenos Aires, Argentina
Carlos F. Satragno, Hip and Knee Unit, Hospital Municipal “Bernardo Houssay”, Buenos Aires, Argentina
Hip and Knee Unit, Hospital Municipal “Bernardo Houssay”, Buenos Aires, Argentina

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Published
2026-10-27
How to Cite
Vega, C. A., Moruno, F., Megey , P. J., Jimenez Ríos, W., & Satragno , C. F. (2026). Clinical and Radiographic Evaluation of the OMICRON 2® Total Knee Prosthesis: A Multicenter Study With Long-Term Follow-up. Revista De La Asociación Argentina De Ortopedia Y Traumatología, 91(5), 427-437. https://doi.org/10.15417/issn.1852-7434.2026.91.5.2225
Section
Clinical Research