[Long-Term Results of Total Knee Replacement Using P.F.C. Sigma System with an All-Polyethylene Tibial Component]

Area of Science:

• Orthopedic Surgery
• Biomaterials Engineering

Background:

• All-polyethylene (all-poly) tibial components offer advantages like durability and lower cost in total knee arthroplasty.
• They eliminate backside wear and are a viable alternative to metal-backed components.

Purpose of the Study:

• To evaluate the long-term clinical results and survivorship of the P.F.C. Sigma all-polyethylene tibial component in primary total knee replacement.
• To assess the outcomes of implants performed between 1999 and 2010.

Main Methods:

• A cohort of 323 total knee replacements (in 289 patients) using the P.F.C. Sigma all-polyethylene tibial component was evaluated.
• Clinical outcomes were assessed using the Knee Society Clinical Rating System (KSS) and roentgenographic evaluation.
• Implant survival was analyzed using Kaplan-Meier survival analysis.

Main Results:

• Average KSS score was 82.6 points, with 213 excellent, 78 good, and 23 satisfactory clinical results.
• The average range of motion was 105.8°.
• Implant survivorship was 98.5% at a mean follow-up of 12.8 years, with low revision rates for aseptic loosening (1 case).

Conclusions:

• Total knee replacement with all-polyethylene tibial components demonstrates favorable long-term clinical outcomes and high survival rates.
• The all-poly design is cost-effective and its indications can extend beyond elderly, low-activity patients.