Metal hip implants: Regulator defends continued use
29 February 2012 Last updated at 00:31 GMT
The head of the government's medical devices regulator has defended the use of all-metal hip implants known to wear badly and cause serious side-effects in patients.
Professor Sir Kent Woods, chief executive of the Medicines and Healthcare products Regulatory Agency (MHRA), told the BBC's Newsnight programme, "the agency has acted with great thoroughness" regarding the issue.
An investigation jointly carried out by Newsnight and the British Medical Journal found that problems with the implants have been known about for decades, but patients have been kept in the dark.
But Sir Kent said clinical trials had not been carried out because it was not possible to "test the wear patterns of human joint replacements", and that people with the implants in question were now being more closely monitored.