Metal-on-metal hip implants, the subject of a handful of high-profile recalls and numerous patient lawsuits, were not linked with an early increase in cancer risk, according to a 7-year study of the U.K.'s National Joint Registry.

hip implant x-ray illustration

Orthopedic device makers Johnson & Johnson (NYSE:JNJ), Stryker (NYSE:SYK) and others got a bit of good news last week after a 7-year study of the U.K.'s National Joint Registry found no increase in cancer rates among metal-on-metal hip implant patients.

Researchers warned that the results were limited and that further observation and study were needed to look for cancers that take longer to develop, but the early findings may deflect some of the concerns surrounding the devices and their makers.

Metal-on-metal hip implants came under scrutiny after Johnson & Johnson subsidiary DePuy Orthopaedics recalled its ASR devices in August 2010, after research showed abnormally high rates of revision surgeries.