High-Flex Knee Replacement Devices May Carry Risks (NewsInferno)
A study conducted between 2003 and 2004 involving one popular high-flex knee (not the Sigma CR150 High-flex Knee or Sigma RP-F Knee systems) that included 47 patients found that at the 32-month mark, 38% experienced aseptic loosening around the femoral components and 21% required a revision surgery due to progressing loosening and pain. The study also found that the higher the flexion achieved (125° compared to 136 °), the more likely patients were to experience loosening of the implant.