Some Zimmer NexGen knee replacement systems have been linked to a high number of problems, including reports of pain, loosening of the implant and failure of the replacement knee leading to revision surgery. OVERVIEW: Several different components used as part of Zimmer NexGen knee replacement systems have been associated with a potential increased risk of problems, which may result in pain, limited range of motion, loosening of components or the need for additional revision surgery. In March 2010, data was presented by a group of knee surgeons that indicates nearly 9% of patients who received the Zimmer NexGen CR-Flex Porous Femoral component required revision knee surgery within two years and 36% showed signs of the replacement knee loosening. In September 2010, recalls were issued for several components due to apparent manufacturing defects or design defects. A Zimmer NexGen MIS recall was issued for more than 68,000 knee components following at least 114 reports of problems that caused some individuals to experiencing loosening of the parts or the need for additional knee surgery. In addition, a Zimmer NexGen LPS recall was issued due to non-confirming and inconsistent geometry. REPORTS OF LOOSENING AND REVISION: At a conference of the American Academy of Orthopaedic Surgeons in March 2010, several prominent knee surgeons presented data on the outcomes of 108 knee replacement patients who received the Zimmer NexGen CR-Flex Porous Femoral component at Rush University Medical Center in Chicago. After only two years, the researchers reported: * 9 patients required knee revision surgery due to loosening and pain * 39 patients showed evidence of radiographic loosening It is suspected that the higher-than-expected failure rate is linked to design problems with Zimmer NexGen replacement knees, as the orthopedic surgeons concluded that they were not caused by surgical errors, problems with the techinque or the type of patient who received the knee implant. More than 150,000 Zimmer NexGen CR and Zimmer NexGen CR-Flex Porous Femoral implants have been sold since 2003, and some doctors have reported experiencing a substantially higher-than-expected failure of the replacement knee within a few years of surgery. The Zimmer replacement knee is a ?high-flex? component, which attaches to the bottom of the thigh bone. In most knee replacement systems, a type of surgical cement is used to hold the implant in place. However, the Zimmer NextGen knee does not use a cement and this may be a design defect which increases the risk of a knee replacement loosening and needing additional surgery to revise the implant.
Answered on Dec 11th, 2012 at 4:02 AM