Polyethylene is used as the liner in both knee and hip replacements. The plastic is extremely strong and wear resistant, but often, if a joint replacement becomes loose, it's because of wear of the polyethylene. One of the techniques we use to strengthen the plastic is to radiate it causing the molecules of the plastic to crosslink together. This makes the plastic stronger, but also more brittle. To offset this problem, the plastic we use is treated with Vitamin E during manufacture. Vitamin E is a natural antioxidant and prevents the increased brittleness of the plastic. I think this will result in less wear of the plastic and longer lasting knee and hip replacements. Plus it looks much prettier in yellow.
Surgeons have used staples for wound closure for many years. They are quick and reliable and usually lead to an OK looking wound.
So why not use them?
I close all wounds with sutures under the skin and glue over the wound. It's harder to do and takes more time but I think this kind of closure has a number of advantages. Patients can shower much sooner and generally have much better looking wounds with the glue closure. There is also mounting evidence, that stapled wounds can lead to a higher rate of wound infection than wounds that are glued.
Overall, patients are much happier with no staples to remove and no "railroad" type marks on their skin.
Dr. Barry Waldman