Graphite May Prevent Complications Caused by Metal-on-Metal Hip Implant
As Published on the DePuy Hip Replacement Website
There are around 93,000 recipients of DePuy’s ASRXL Acetabular System and the ASR Hip ResurfacingSystem worldwide when they were pulled backfrom the market in August 2010 following therelease of data showing defectiveness in one outof eight patients to whom they were implanted.Yet there is good news for the future of metal-on-metal implants.
Researchers from US and Germany have discovered astratum of “graphitic carbon” on the head part of all-metal hip implants, new research presents. Thegraphite compound may enhance the safetyandeffectiveness of future hip implant products. TheBritish Hip Society proposes for an informal all-metalhip replacement ban.
“Graphite has been used as a lubricant for over acentury. It is a classic lubricant, and it appears toform naturally,” according to Laurence Marks, oneof the researchers and also a professor atNorthwestern University, teaching materials scienceand engineering.
Marks further speculates that subsequentmanufacturers of metal-on-metal hip implantscould improve their devices to encouragegraphite formation to prevent metal poisoningand corrosion. The benefits of graphitecompound was discovered in a recent studyfunded by the National Institutes of Health thatwas published in the medical journal, Science.
“Now that we have a handle on how they areworking and why they were working well, we canstart to design them to make them better,” saysMarks.
Problems with the design of DePuy metal-on-metal hip devices may had led to the rubbing ofmetal components against each other andcasting microscopic metal bits into the body:
• Additional hip replacement or revision surgery• Loosening of hip device• Detachment of the hip device from the bone• Unexplained hip pain• Hip dislocation• Swelling• Complete hip failure• Metallosis (metal toxicity or blood poisoning)
• Pseudotumors• Tissue damages• Genotoxicity (genetic damage)• Bone fractures• Bone loss• Inflammatory reactions• Presence of chromium and cobalt in the bloodthat may lead to cancer
“Most major medical centers have seen issues withthis device,” Dr. Joshua J. Jacobs, the chairman oforthopedic surgery at Rush University Medical Centerin Chicago, says in a newspaper interview. “This doesnot come as a surprise.”
Based on data collected as of October 2010, therewere already about 3,500 DePuy hip replacementlawsuits that Johnson & Johnson faces. They wereamong those affected by the failures and defects (e.g.fractures, displacements, loosening) of DePuydevices.