Do some total hip replacements last longer because of the way they are sterilized before packaging? This is the question studied by researchers at the Anderson Orthopaedic Research Institute in Virginia.
The authors looked at the rate of wear for two different hip implants. They followed patients for up to 16 years. Sterilization is used to kill any bacteria or viruses in the materials. One group of implants was sterilized using gamma rays (irradiation). The second group was sterilized using ethylene oxide, a chemical that treats the surface of the implant.
Before starting the study, the scientists thought there could be three possible results:
to patient.
They found that the first theory was correct. There were no real differences in wear rates regardless of the type of sterilization process used. The wear rates were about the same, even years later.
The researchers plan to keep watching both groups as long as possible. In the meantime, they say the results of their study should help calm patients’ fears. A big increase in wear many years after receiving the implant isn’t likely.