If they have any symptoms, Dunedin Hospital metal-on-metal hip implant recipients are being checked for ill effects even if their implant has not been recalled, a surgeon's report to Otago GPs says.
Concerns about metal-on-metal implants include a higher-than-acceptable failure rate, and toxins leaching into the blood.
In a monthly newsletter to GPs, orthopaedic surgeon Associate Prof David Gwynne-Jones said that of about 5000 Otago hip replacements in the past 13 years, fewer than 20 were metal-on-metal.
"If any patient known to have a metal-on-metal bearing presents with hip symptoms, they should have an up-to-date X-ray and be referred to the orthopaedic department for further investigation and management," Prof Gwynne-Jones said in the newsletter.
"This will include serumchromium and cobalt levels and, if elevated, further imaging such as an MRI scan."
The direction includes Birmingham and Pinnacle implants, for which there have been no recalls or official warnings.
DePuy's ASR joint wasrecalled in 2010, and the Stryker Mitch THR last month.
Five Dunedin patients received the ASR implant, one of whom had died from unrelated causes, Prof Gwynne-Jones said.
No-one in Dunedin received the THR.
The Birmingham implant, nine of which had been used in Dunedin, appeared to be performing satisfactorily according to the New Zealand joint registry, he said.
Last month, the Otago Daily Times reported Ken Burt, of Dunedin, was waiting for the second of two operations to deal with a reaction to a Pinnacle metal-on-metal hip implant.
He demanded to know why the Pinnacle had not been recalled by the authorities.
On Thursday, Mr Burt said he was still waiting for the operation.