Device Alert Issued Regarding Unicondylar Sled Knee Prostheses

Concerns Raised In Relation To Early Wear Of Plastic In Device

14.07.2014

The Medicines and Healthcare Products Regulatory Agency (MHRA) has issued a device alert regarding the risk of problems related to certain models of unicondylar sled knee prostheses.

A unicondylar knee prostheses is a partial replacement where one compartment of the knee is replaced after suffering from a degenerative disease, such as osteoarthritis, or trauma causing damage to the knee.

According to the organisation, the notice relates to metal-backed tibial plateau Endo-Model 7mm versions of the device manufacturing by Waldemar Link GmBH & Co with the catalogue numbers 15-2030/01, 15-2030/05 and 15-2030/09.

It has stated that a risk of early wear has been identified in relation to the ultra high molecular weight polyethylene plastic part of the tibial plateau.

The MHRA has called for medical professionals to ensure patients implanted with the devices in the past five year are identified, as well as to consider an annual review of those patients.

In addition, any explanted devices should be retained for investigation, while any adverse events should be reported to both the MHRA and the manufacturer.

Expert Opinion
It is worrying to see these concerns raised regarding the early failure of an orthopaedic device, with major surgery the only real approach to correct the issue.

"Knee replacement surgery is a major operation where mobility issues will increase the with number of operations required. Given that a problem has been identified concerning the performance and durability of knee prostheses, we urge the manufacturer to voluntarily recall the implant until the precise issue has been identified to ensure that more patients need not unnecessarily suffer. To continue to market this prostheses with the knowledge that it may not perform to the standards expected from knee implants generally or other implants on the market it putting patient safety at risk.

"Through our work on behalf of patients affected by problems with metal-on-metal hip implants, we have seen the true, serious impact that faulty medical implants can have on the everyday lives of patients. This has been publicly highlighted through recent scandals concerning metal on metal hip implants.

"Both patients and medical professionals place great faith in the fact that the devices used in treatment meet the required regulatory standards and pose little risk of failure. Sadly, cases of this kind can serve to erode such trust, so it is vital that a full investigation is held to properly understand what can be done to prevent these product failures from happening again. However, the investigation should not be carried out whilst patients continue to be provided with this product which has a known risk of early failure."
Kevin Timms, Solicitor