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The P.F.C. sigma RP-F TKA designed for improved performance: a matched-pair study.
Sanjay K Gupta1, Amar S Ranawat, Vineet Shah
1Department of Orthopedic Surgery, Lenox Hill Hospital, New York, NY 10021, USA.
Orthopedics
|September 28, 2006
Summary
The P.F.C. Sigma RP-F knee replacement offers significantly improved range of motion (ROM) after total knee arthroplasty (TKA). This advanced design enhances postoperative ROM, benefiting patients regardless of their initial flexibility.
Area of Science:
- Orthopedic Surgery
- Biomedical Engineering
- Knee Arthroplasty Design
Background:
- Total knee arthroplasty (TKA) aims to restore function and mobility.
- Existing knee implant designs may limit postoperative range of motion (ROM).
- The P.F.C. Sigma RP-F (rotating-platform, high flexion) knee was developed to enhance ROM.
Purpose of the Study:
- To evaluate the effect of the P.F.C. Sigma RP-F knee design on postoperative ROM.
- To compare the ROM outcomes of the Sigma RP-F knee with a standard rotating-platform knee.
Main Methods:
- A retrospective study matched 50 patients receiving the Sigma RP-F knee with 50 patients receiving a rotating-platform knee.
- Patients were matched for age, sex, BMI, diagnosis, follow-up duration, and preoperative ROM.
- Postoperative active ROM was measured and compared between the two groups.
Main Results:
- The Sigma RP-F group showed a significantly greater mean increase in active ROM (17 degrees) compared to the rotating-platform group (6 degrees) (P =.0011).
- In patients with less than 120 degrees preoperative ROM, the Sigma RP-F group achieved a greater increase (27 degrees) versus the rotating-platform group (16 degrees) (P = .006).
- The P.F.C. Sigma RP-F design improved ROM irrespective of the patient's preoperative motion.
Conclusions:
- The P.F.C. Sigma RP-F knee implant design leads to superior improvements in active ROM after TKA.
- This enhanced ROM is achievable even in patients with limited preoperative motion.
- The study supports the efficacy of the Sigma RP-F design in maximizing knee joint mobility post-surgery.
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