Thursday, June 2, 2011

Progress in understanding the implications of systemic effects of MOM and poly implants?

I was writing to a friend of mine who is a pathologist in a university hospital setting last nite and was recounting the key milestones of “progress” in understanding the systemic effects of  MOM and poly implants on certain organs.  Remember, the systemic effects of implants address the effects wear particles  which may accumulate in your organs, especially in the lymph nodes, liver and spleen.  I happen to also be interested in the Kidney. This is what I found.

 Year:  1996 (I just arbitrarily started in that year to see how far we have come .) 

Article:  Granular histiocytosis of pelvic lymph nodes following total hip arthroplasty. The presence of wear debris, cytokine production, and immunologically activated macrophages

Conclusion: While local biological factors leading to failure of prostheses are currently under intense investigation, the mechanisms and importance of regional and systemic immune responses to wear debris require further study

Year:  2000

Article: Dissemination of wear particles to the liver, spleen, and abdominal lymph nodes of patients with hip or knee replacement.

Conclusion: “The long-term effects of accumulated wear particles in the liver and spleen are unknown.” _____________________________________________________________________________________________

Year:  2004

Article: Accumulation in liver and spleen of metal particles generated at nonbearing surfaces in hip arthroplasty

Conclusion:Currently available methods lack the sensitivity and specificity necessary to detect very low concentrations of submicrometer polyethylene particles and probably underestimated the prevalence of polyethylene wear debris in the liver and spleen.”


Year: 2009

Article: Metal-on-metal bearing surfaces

Conclusion: “Advances in the understanding of the operant wear mechanisms in these bearings provide strategies for reducing the burden of metal released into the periprosthetic milieu, which in turn will mitigate the concerns about the biologic response to the metal debris. Continued surveillance of patients with these bearings is warranted”


Year: 2010

Article: Cobalt ions induce chemokine secretion in a variety of systemic cell lines

Conclusions: Metal ion toxicity both locally and systemically following MoM hip replacements remains a concern. Cobalt ions have been shown to induce secretion of proinflammatory chemokines locally; however, little is known about their effect systemically.


So, after 14 years of studies, I can’t find any real experts who can do the following:

·         Provide a test to measure the systemic levels in any organ.  I would like to hear from anyone who has identified a source who can provide these tests.

·         Articulate the effects of these materials other than of course in rats

You know what I think?  Any settlement that Depuy makes should include funding the appropriate studies to figure out what the effects of these materials might are.  In fact, a board should be set up comprised of medical people and others to review proposals for research in this area.  Depuy can fund the studies.  In fact, the lawyers should make this a condition of any settlement.  Someone needs to be responsible for seeing that this research is funded actively.


No comments:

Post a Comment