LONDON Smith & Nephew is withdrawing a component of one of its all-metal artificial hip systems, following a higher than normal level of patient problems with the device.
The voluntary recall will add to concerns about the safety of metal-on-metal hips, although the British company said on Friday the issues with its system were different to those seen with some other all-metal implants.
A small number of patients experienced problems including infections, fractures and dislocations - but there was no evidence of "metallosis", or the build-up of metallic debris in the body, a spokesman said.
Smith & Nephew is withdrawing the optional metal liner, or cup, component of its R3 Acetabular System. Surgeons, however, will still be able to use the system using alternative non-metal liners and the company said it did not anticipate any delays to surgery.
The decision follows an analysis of clinical results showing that 1.6 percent of patients with the system needed revision surgery each year, which is above the 1 percent guideline set by Britain's National Institute for Health and Clinical Excellence.
"We regularly review the effectiveness of our products and are not satisfied with the clinical results of this component," said Andy Weymann, Smith & Nephew's chief medical officer.
Approximately 7,700 of the metal liners have been implanted since the component was introduced in 2007. Procedures using the component accounted for less than 1 percent of Smith & Nephew's global hip implant revenue last year.
Metal-on-metal hips were developed to be more durable than traditional implants, which combine a ceramic or metal ball with a plastic socket.
But recent experience suggests they may actually do worse, prompting the high-profile recall of one device made by Johnson & Johnson.
(Reporting by Ben Hirschler. Editing by Jane Merriman)