Gupta Sanjay K, Ranawat Amar S, Shah Vineet, Zikria Bashir A, Zikria Joseph F, Ranawat Chitranjan S
Department of Orthopedic Surgery, Lenox Hill Hospital, New York, NY 10021, USA.
Orthopedics. 2006 Sep;29(9 Suppl):S49-52.
The press fit condylar P.F.C. Sigma RP-F (rotating-platform, high flexion) knee is designed to provide a range of motion (ROM) of 155 degrees without compromising wear, polyethylene contact stresses, patellofemoral tracking, or stability. The first 50 TKA surgeries using the Sigma RP-F knee performed at the author's institution were matched to 50 rotating-platform knees for age, sex, body mass index, preoperative diagnosis, duration of follow-up, and preoperative ROM to determine the effect of design on postoperative ROM. The mean increase in active ROM in the Sigma RP-F group was 17 degrees, compared with 6 degrees in the rotating-platform group (P =.0011). The mean increase in active ROM in patients who had less than 120 degrees of preoperative motion was 27 degrees in the Sigma RP-F group, compared with 16 degrees in the rotating-platform group (P = .006). With the new P.F.C. Sigma RP-F design, greater ROM can be achieved independent of preoperative ROM.
压配型髁P.F.C. Sigma RP-F（旋转平台，高屈曲）膝关节的设计旨在提供155度的活动范围（ROM），同时不影响磨损、聚乙烯接触应力、髌股关节轨迹或稳定性。在作者所在机构进行的首批50例使用Sigma RP-F膝关节的全膝关节置换术（TKA）与50例旋转平台膝关节在年龄、性别、体重指数、术前诊断、随访时间和术前ROM方面进行匹配，以确定设计对术后ROM的影响。Sigma RP-F组主动ROM的平均增加为17度，而旋转平台组为6度（P = 0.0011）。术前活动度小于120度的患者中，Sigma RP-F组主动ROM的平均增加为27度，旋转平台组为16度（P = 0.006）。采用新的P.F.C. Sigma RP-F设计，可实现更大的ROM，且与术前ROM无关。
