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Researchers at the University of Nebraska Medical center recently published their results of a study in which they developed an optical imaging agent to detect inflammation due to wear debris generated from implants. In this study, a N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-based optical imaging contrast agent (P-IRDye) was developed and used for the detection of wear particle-induced inflammation employing a murine calvaria osteolysis model. The particle-induced osteolysis of calvaria was evaluated by H&E, tartrate-resistant acid phosphatase (TRAP) staining and μ-CT after necropsy. One-day post particle implantation, P-IRDye was administrated to the mice via tail vein injection. Live imaging of the animals 6 days after implantation revealed the preferential distribution and sustained retention of the macromolecular contrast agent at the site of particle implantation. Immunohistochemical staining and FACS analyses of the calvaria-associated soft tissue revealed extensive uptake of the HPMA copolymer by F4/80, Ly-6G (Gr1) and CD11c positive cells, which accounts for the retention of the macromolecular probes at the inflammatory sites.

The FDA has issued a mandate to manufacturers of re-usable medical devices to design with re-cleaning of the these devices in mind. This mandate is in response to an on-going effort to reduce the risk of infection, contamination, or disease transmission due to improperly cleaned devices. Device design should include smooth interior surface, avoidance of sharp corners and blind spots, as well as easy disassembly for cleaning. Material choice should be selected with reprocessing in mind.

More information can be found on the FDA's web site.

The on-going discussion of patient response to metal-on-metal hip implants has recently increased. For the past few years, papers presented at ORS and AAOS have discussed concerns about tissue response to metal ions and debris liberated from wear in metal-on-metal hip implants. These articles allege that the metal ions can result in pseudo-tumors in some patients. The FDA has recently requested that all orthopedic manufacturers who produce a metal-on-metal (MOM) implant conduct clinical studies on patients who have received a MOM implant. A NY Times article discusses the nature of this request. A recent NPR story also talks about issues with MOM, and Depuy's recent recall of their ASR system.

The FDA will be hosting a public workshop on the Reprocessing of Reusable Medical Devices on June 8th and 9th, 2011 in Silver Springs, MD. The purpose of the workshop is to discuss factors affecting reprocessing quality, device design as it relates to reprocessing reusable medical devices, reprocessing methodologies, validation methodologies, healthcare facility best practices, and FDA’s plans to address the identified issues. CPG researcher Stephen Spiegelberg is an invited speaker at the workshop. Further information and registration details can be found here.

The next ASTM meeting for medical device development (Committee F04) will be meeting from May 15-17th, 2011, in Anaheim, California. This meeting will focus on ASTM standards development for the characterization of UHMWPE, PEEK, and other biomedical plastics, as well as testing protocols for medical devices and cleanliness of medical devices. Contact Cambridge Polymer Group for more details, or visit the ASTM web site.

The  Medical Grade Polymers 2011 conference will take place September 13 - 14, 2011 at the Hilton City Avenue in Philadelphia, Pennsylvania, United States. The program will have papers from top medical device manufacturers and polymer suppliers, including details of high performance implantable materials, coatings, cardiovascular devices, antimicrobials and hygiene, and many other topics.

Cambridge Polymer Group researcher Stephen Spiegelberg will be presenting a paper on the use of antioxidants in medical grade thermoplastics.

More information on the conference call be found at the Medical Plastics Website.