In vivo kinematics of mobile-bearing total knee arthroplasty during deep knee bending under weight-bearing conditions
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Kazuma Futai • Tetsuya Tomita • Takaharu Yamazaki • Masashi Tamaki • Hideki Yoshikawa • Kazuomi Sugamoto
- چاپ و سال / کشور: 2011
Description
Purpose Little is known about the in vivo kinematics of mobile-bearing total knee arthroplasty, especially at deep knee flexion under weight-bearing conditions. Methods In vivo knee kinematics was analyzed for 12 patients (13 knees) implanted with PFC-Sigma Rotating Platform-Flex (RP-F) prostheses. Under fluoroscopic surveillance, each patient performed weight-bearing deep knee bending. Motion between each component was analyzed using a two- to three-dimensional registration technique, which uses computer-assisted design models to reproduce the spatial positions of the femoral and tibial components and a polyethylene insert (implanted with four tantalum beads) from single-view fluoroscopic images. Results External rotation of the femoral component on the tibial tray was mostly caused by rotation of the polyethylene insert on the tibial tray. The femoral component typically exhibited a central pivot pattern from extension to 80 relative to the tibial component. From 80 to 120, bilateral condyles moved backward. In an upright standing position, the femoral component had already rotated externally relative to the tibial component by 7.8 ± 7.5, and the polyethylene insert had also rotated 8.2 ± 6.2 externally on the tibial tray. Conclusion The present results demonstrated that mobilebearing mechanisms with this prosthesis might reduce articular contact stress in vivo.
Knee Surg Sports Traumatol Arthrosc (2011) 19:914–920 DOI 10.1007/s00167-010-1262-6 Received: 17 September 2009 / Accepted: 30 August 2010 / Published online: 16 September 2010
