The use of metal-on-metal total hip arthroplasty implants was not linked to a higher risk of cancer in patients compared to the use of non-metal-on-metal devices.
“The overall risk of cancer or risk of death because of cancer is not increased after metal-on-metal hip replacement,” the authors wrote in their study abstract. “The well-patient effect and selection bias contribute to the findings concerning mortality. Arthrocobaltism does not increase mortality in patients with metal-on-metal hip implants in the short-term.”
The researchers added, “Metal-on-metal hip implants should not be considered safe until data with longer follow-up time are available.”
Using information from the Finnish Arthroplasty Register, the researchers compared 10,728 patients with metal-on-metal (MoM) hip implants to 18,235 patients who received non-MoM hip implants during procedures performed between 2001 and 2010. The researchers followed patients from the date of hip replacement until December 31, 2011 or until the date of patients’ deaths. The average follow-up in the MoM group was 4.6 years and 6 years for the comparison group. The investigators obtained data on patients’ cancer rates and cancer-related causes of death from the Finnish Cancer Registry and Statistics Finland.
The researchers found the cancer risk was not higher in the MoM patients compared to non-MoM patients; however, the risk of soft-tissue sarcoma and basalioma was higher in the metal-on-metal cohort. Overall, the risk of death was lower in MoM group compared to the non-MoM group. — by Renee Blisard Buddle
Disclosure: Mäkelä has no relevant financial disclosures. The study was funded by a Turku University Hospital Grant and an Orion-Farmos Research Foundation Grant.