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Regulation of UHMWPE biomaterials in total hip arthroplasty.

This manuscript provides a brief history of the development of ultrahigh molecular weight polyethylene (UHWMPE) biomaterials and how the U.S. Food and Drug Administration (FDA) regulates medical devices. The flowchart used to decide whether a device is medium or high risk, known as the 510(k) flowchart, is illustrated by taking several examples through the flowchart. In order to demonstrate how changes to UHWMPE material used in the acetabular liners of total hips have been regulated, two major modifications to UHMWPE, highly crosslinked polyethylene and Vitamin E polyethylene, are taken through the flowchart. This manuscript describes the testing that has been provided to demonstrate safety and effectiveness of these modifications, as well as an explanation why the testing was supplied to the FDA.