NexGen Complete Knee Solution MIS stemmed tibial component (various sizes)
Hazard alert - faulty threads potentially preventing installation of drop-down stem extension or stem plug
Consumers and health professionals are advised that Zimmer, in consultation with the TGA, has issued a hazard alert regarding its NexGen Complete Knee Solution MIS total knee procedure stemmed tibial component (various sizes).
The affected medical device is used in knee replacements and comprises a tibial baseplate with a threaded hole into which a drop-down stem extension or stem plug can be screwed.
A manufacturing defect left faulty threads in some devices manufactured before 3 April 2014, potentially preventing proper installation of the drop-down stem extension or stem plug.
In some cases this could potentially lead to loosening or failure of parts of the implant.
The defect was discovered after several overseas reports of surgeons having difficulty installing drop-down stem extensions or stem plugs. There have been no Australian reports of this issue.
Zimmer has advised that no unimplanted affected devices remain available in Australia
Information for consumers
This issue potentially affects 44 devices that have been implanted in patients in Australia between May 2010 and April 2011.
Zimmer has written to surgeons who have implanted these devices, providing further information about the issue and advice regarding follow-up monitoring.
In most cases any problems caused by this issue would be evident during implantation surgery and the surgeon would already be aware of necessary follow-up actions.
If you have any questions or concerns, please contact your surgeon or the hospital where the surgery was undertaken.
Information for health professionals
If you are treating patients who have had a knee replacement and are concerned about the above issue, reassure them that the likelihood of them experiencing related problems is very low.
If you suspect there may be a problem relating to this issue, or if patients continue to have questions or concerns, refer them to their surgeon or the hospital where the surgery was undertaken.
Information for orthopaedic surgeons
Zimmer has written to surgeons who may have received or implanted NexGen Complete Knee Solution MIS total knee procedure stemmed tibial components, providing further information about the above issue.
Zimmer has already quarantined unused stock.
Surgeons would be aware of most potential issues caused by this problem at the time of implantation, however:
- additional bone loss may occur if the MIS tibial component is cemented in place when the issue is identified and the device is required to be removed and replaced
- if the tibial component is implanted without a drop-down extension, early revision may be needed due to loosening and/or infection
- if the stem extension does not fully seat due to thread misalignment, the articular surface may not fully lock and disassociation may occur.
If you are treating a patient who received a potentially affected device, it is recommended that you continue your normal post-operative follow-up routine. Remain particularly alert to the potential issues outlined above.
If you have any questions or concerns about this issue, contact Zimmer.
Consumers and health professionals are encouraged to report problems with medical devices. Your report will contribute to the TGA's monitoring of these products. For more information see the TGA Incident Reporting and Investigation Scheme (IRIS).
The TGA cannot give advice about an individual's medical condition. You are strongly encouraged to talk with a health professional if you are concerned about a possible adverse event associated with a medical device.