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Asian-specific total knee system: 5-14 year follow-up study
Kunihiro Hosaka1, Shu Saito, Takao Ishii
1Department of Orthopedic Surgery, Nihon University School of Medicine, 30-1 Oyaguchi, Kamimachi, Itabashi-ku, Tokyo 173-8610, Japan. kunihiro619@hotmail.com
BMC Musculoskeletal Disorders
|November 4, 2011
Summary
The Flexible Nichidai Knee (FNK) prosthesis shows excellent mid- to long-term outcomes in Asian patients undergoing total knee arthroplasty (TKA). This specialized implant significantly improves knee function and survivorship, addressing anatomical differences in Asian populations.
Area of Science:
- Orthopedic Surgery
- Biomedical Engineering
- Arthroplasty Research
Background:
- Anatomical differences exist between Asian and Caucasian knee sizes, impacting total knee arthroplasty (TKA) outcomes.
- Standard TKA prostheses are often designed for Western Caucasian anatomy, potentially leading to suboptimal fit for Asian patients.
- The Flexible Nichidai Knee (FNK) system was developed as a TKA solution tailored for Asian patients.
Purpose of the Study:
- To retrospectively investigate the clinical outcomes and survivorship of the Flexible Nichidai Knee (FNK) system in Asian patients.
- To evaluate the efficacy of the FNK prosthesis in addressing the specific anatomical needs of the Asian population.
- To assess the mid- to long-term performance of the FNK system for total knee arthroplasty.
Main Methods:
- A retrospective study of 1055 primary TKAs using the FNK system in 595 patients with osteoarthritis (OA) in Japan.
- Clinical evaluation included knee and function scores, range of motion (ROM), and radiographic assessments over a minimum 5-year follow-up.
- Survivorship analysis was performed using revision for any reason and aseptic failure as endpoints.
Main Results:
- 890 knees in 502 patients (96.0% follow-up rate) were analyzed with a mean follow-up of 8.3 years.
- Significant improvements were observed in knee scores (41.3 to 90.3) and function scores (39.1 to 76.2) (p < 0.001).
- Mean ROM significantly improved for both FNK posterior cruciate retaining (CR) and posterior-stabilized (PS) types; survivorship rates were 99.4% at 5 years and 96.2% at 12.5 years.
Conclusions:
- The Flexible Nichidai Knee (FNK) prosthesis demonstrates excellent mid- to long-term survivorship in Asian patients.
- The FNK system provides significant improvements in clinical outcomes, including knee function and range of motion.
- This TKA prosthesis is a suitable option for Asian patients, addressing their specific anatomical considerations.
