Five studies to read for the latest research in metal-on-metal hips
Published on: 15 April, 2014
There is no doubt that there has been an increased level of awareness regarding the the clinical performance of metal-on-metal bearing surfaces in recent years, much higher than anyone involved in orthopaedics likes to see. There is also significant awareness in the patient population, thanks to many articles published and presented in mainstream media.
A recent article by Orthopedics Today summarized five articles that were recently published with a focus on metal-on-metal total hip arthroplasty. If you’re a subscriber to Orthopaedics Today, you can read this summary here (http://www.healio.com/orthopedics/hip/news/online/%7Be8c1fa50-e17c-41db-a21d-4d0c78c530ce%7D/five-stories-to-read-for-the-latest-in-metal-on-metal-research), otherwise we’ve provided the full references for you below.
Study: Smaller MoM bearings performed better for patients with degenerative joint disease
Engh CA. J Bone Joint Surg Am. 2014;doi:10.2106/JBJS.M.00164.
Blood cobalt levels, device type may predict metal-on-metal hip failure
Langton D. BMJ Open. 2014;doi:10.1136/bmjopen-2012-001541.
Study: Good results found for second-generation metal-on-metal total hip bearings
Lass R. J Bone Joint Surg. 2014. doi:10.2106/JBJS.M.00748.
Metal-on-metal total hip arthroplasty implants did not increase overall cancer risk
Mäkelä K. Acta Orthop. 2014; doi: 10.3109/17453674.2013.878830
Second generation MoM hip implants associated with adverse reactions
OrthopaedicstodayEUROPE. NOVEMBER/DECEMBER 2013
The 2013 NJRR “Metal on Metal Total Conventional Hip Arthroplasty” report into these bearing surfaces reported a higher rate of revisions for the metal on metal bearing surface compared to metal on polyethylene since 2008. The main reasons for these revisions have been metal related pathology (30.5%), loosening/lysis (28.3%) and infection (11.7%). Use in Australia has certainly declined with only 110 procedure being performed with this bearing surface in 2012. There is also a difference in the rate of revision and age - patients aged less than 75 years of have have a higher revision rate. Similarly, the rate of revision is higher where head size is greater than 32mm, regardless of age.
There is no doubt that this is an area that warrants ongoing data collection and monitoring. It will be interesting to see how the data presented clinical studies compares to the outcomes that registries such as the NJRR report.