Standards Development

ASTM International has recently published a new update to ASTM F2759 - 11, Standard Guide for Assessment of the Ultra High Molecular Weight Polyethylene (UHMWPE) Used in Orthopedic and Spinal Devices. The scope of this revised standard includes exanded description of the biocompatibility of UHMWPE materials blended with Vitamin E. This revised standard provides additional guidance for manufacturers of hip, knee, upper extremity, and spinal implants seeking to evaluate the biocompatibility of UHMWPE blended with Vitamin E.

At the November 2008 ASTM meeting for F04, the task force convened to continue to develop an "umbrella" type document listing all of the recommended preclinical testing that should be performed for UHMWPE implants components by manufacturers. The working group reviewed the results of the first subcommittee ballot. The revised draft standard will be reballoted in December. The scope of this draft standard includes conventional and highly crosslinked UHMWPE, with and without Vitamin E. This standard is expected to provide guidance for UHMWPE testing to manufacturers of hip, knee, upper extremity, and spinal implants. The intent of this draft standard is to provide the basis for a future FDA guidance document for UHMWPE.

At the May 2008 ASTM meeting for F04, a new task force convened to develop an "umbrella" type document listing all of the recommended preclinical testing that should be performed for UHMWPE implants components by manufacturers. The scope includes conventional and highly crosslinked UHMWPE, with and without Vitamin E. This standard is expected to provide guidance for UHMWPE testing to manufacturers of hip, knee, upper extremity, and spinal implants. The intent of this proposed standard is to provide the basis for a future FDA guidance document for UHMWPE. Participation in this task force continues to be open to all. To join the task force and participate in the standard development process, please contact the Task Force Chair, Prof. Warren Haggard, U. of Memphis or the Vice Chair, David Schroeder, from Biomet. The next face-to-face meeting of the task force, to discuss the initial ballot results, is expected to take place at next ASTM meeting in November 2008.

At the November 2007 ASTM meeting for F04, a new task force was created to develop an "umbrella" type document listing all of the recommended preclinical testing that should be performed for UHMWPE implants components by manufacturers. The scope will include conventional and highly crosslinked UHMWPE, with and without Vitamin E. This standard is expected to provide guidance for UHMWPE testing to manufacturers of hip, knee, upper extremity, and spinal implants. The intent of this proposed standard is to provide the basis for a future FDA guidance document for UHMWPE. Development of the standard will begin immediately via email, with the goal of providing a standard for ballot as soon as possible. Participation in this task force is open to all. To join the task force and participate in the early standard development process, please contact the Task Force Chair, Prof. Warren Haggard, U. of Memphis (whaggrd1@memphis.edu) or the Vice Chair, David Schroeder, from Biomet (Dave.Schroeder@biomet.com). The first face-to-face meeting of the task force, ideally to discuss the initial ballot results, is expected to take place at next ASTM meeting in May 2008.

At the November 2007 ASTM meeting for F04, it was announced that the new draft standard, "Standard Specification for Ultra-High Molecular Weight Polyethylene Powder Blended With Alpha-Tocopherol (Vitamin E) and Fabricated Forms for Surgical Implant Applications," had successfully traversed sub-committee and main committee ballots and has been approved for publication. This specification covers Vitamin E-blended UHMWPE resin and fabricated forms of blended UHMWPE resin. The reference number (i.e., designation) for this standard is not yet available, but please check the ASTM site regularly for updates. Because no further revisions to this specification are planned in the near future, the task force voted unanimously to disband until further notice. No additional standards work on Vitamin E-blended UHMWPE is expected to take place at ASTM in 2008.

The formation of two new task forces related to Vitamin E in Medical Grade UHMWPE were announced at the November 2006 F04 ASTM Meeting in Atlanta. One task force will be dedicated to creating a material specification for medical grade UHMWPE materials blended with commercially available Vit E-containing resin. A second task force will be convened to standardize test methods for characterizing Vitamin E levels in blended and doped UHMWPE materials. Both task forces will be convene for the first time at the ASTM meeting on Thursday, May 24, 2007 at the Waterside Convention Center; Norfolk, VA US. See the ASTM website for more details about the upcoming F04 meeting. Contact Steve Kurtz, Chair, for more details about the Vitamin E Material Specification Task Force; and Ray Gsell, Chair, for more information about standards for characterizing Vitamin E materials.

At the November 2006 ASTM meeting for F04, it was announced that the new standard, "ASTM F2565-06 Standard Guide for Extensively Irradiation Crosslinked Ultra-High Molecular Weight Polyethylene Fabricated Forms for Surgical Implant Applications," has now been published by ASTM. This guide covers the test methods recommended for characterization of highly crosslinked UHMWPEs. This standard is now available for download from the ASTM website. Because no further updates to this specification are planned in the near future, the task force voted unanimously to disband until further notice. The task force dedicated to developing a shelf life standard for UHMWPE also voted to disband due to lack of interest in developing standards related to this topic. Consequently, no further work on crosslinked materials or shelf life testing will take place at ASTM in 2007.

A new standard, "Standard Guide for Extensively Irradiation Crosslinked Ultra-High Molecular Weight Polyethylene Fabricated Forms for Surgical Implant Applications," has successfully traversed Main and Subcommittee Ballot approval by ASTM. This guide covers the test methods recommended for characterization of highly crosslinked UHMWPEs. As this standard has been recently approved (as of May 2006), no designation number is currently available and it is not yet available for download on the ASTM website.

ASTM has now published F2381-06, "Standard Guide for Evaluating the Extent of Oxidation in Ultra-High-Molecular-Weight Polyethylene Fabricated Forms Intended for Surgical Implants." This updated method has incorporated additional details regarding the limits of integration for the carbonyl region of the FTIR spectrum. The standard is currently available to download from the ASTM website. At the May 2006 ASTM meeting, ongoing development of the standard was discussed to include protocols for measuring oxidation in retrieved components.

Orthopedic surgeons and researchers at the University of Turin, Italy, will be convening a new, one-day symposium about UHMWPE on Friday, March 18, 2005. The meeting will be held at the Museo dell'Automobile "Carlo Biscaretti di Medicina del Lavoro Ruffia", Corso Unità d'Italia, 40 - Torino. The meeting, directed primarily towards clinicians and researchers, is being organized (in part) to discuss advances in the stabilization of polyethylene using Vitamin E. Click here to download the meeting agenda. For further details, please visit the conference website or contact Prof. Luigi Costa.