Stryker EIUS unicompartmental knee prosthesis

The TGA has become aware that the EIUS unicompartmental¹ knee prosthesis supplied by Stryker Australia has a higher than expected revision rate (rate of revision surgery). Supply of the product in Australia has been suspended.

Surgeons should ensure that patients are fully aware of the symptoms that might indicate the need for orthopaedic review and possible revision surgery (corrective surgery), and that patients should seek advice if they experience these symptoms.

In Australia, 141 of the EIUS unicompartmental knee prostheses have been implanted and 26 of these have required revision surgery.

This revision rate of 18.5% for the EIUS unicompartmental knee prosthesis compares to a revision rate of 8.6% for other unicompartmental devices at 5 years post-implantation as reported in the National Joint Replacement Registry of the Australian Orthopaedic Association.

Higher than expected revision rates for the EIUS unicompartmental knee prosthesis have also been reported by the National Joint Registry of England and Wales.

Information for orthopaedic surgeons

Implanting and treating surgeons are in a unique position to exercise medical judgment as it relates to individual patient experience with the EIUS unicompartmental knee prosthesis. The TGA wishes to increase surgeon awareness of the EIUS unicompartmental knee prosthesis revision results reported by the two registries.

Surgeons should ensure that patients are properly informed about symptoms (particularly pain and swelling) that might indicate the need for review and possible revision surgery, and the need for follow-up care should these symptoms arise.

Surgeons should continue to follow patients according to their normal post-operative course of treatment for unicompartmental devices generally.

Information for health professionals

Pain accompanies all the leading causes of revision with unicompartmental devices which are:

• implant loosening
• disease progression (up to 50% of all revisions)
• procedure-related issues

Pain and swelling in the operated knee are sensitive problem indicators and require orthopaedic follow-up.

Rapid development of persistent local pain occurs when there is a failure in the mechanical operation of the device. Patients in pain need to be reviewed by their orthopaedic surgeon to determine whether corrective surgery is needed.

Information for patients

If pain develops in a knee that has undergone replacement surgery after the recovery period, patients should seek advice from their orthopaedic surgeon.

Reference

1. A unicompartmental knee prosthesis is designed to conserve bone in situations where only one portion of the knee joint is worn.