Chances are the type of hip replacement you received is very different from what your grandmother might have been given. That’s because we are now on the third-generation of hip replacement implants.
Third-generation means the implants have changed in major ways three times since they were first introduced more than 40 years ago. Changes in implant materials, surface, and component parts (e.g., liners, sockets, femoral head and stem) have all been improved many times over in those four decades.
In the 1950s, Teflon and stainless steel parts were used. This was replaced in the 1960s and 70s with ultrahigh molecular weight polyethylene sockets on a metal head. Ceramic implants were developed during that time as well and have continued until today.
Thinner shells combined with an ability to polish itself have made it possible to reduce wear and prolong the life of the implant. The self-polishing feature makes it possible for scratches that develop to smooth away with movement. Manufacturers have been able to create an implant with a larger femoral head to increase joint stability while preserving mobility (motion). The risk of hip dislocation is lower with a larger femoral head size.
In the future, we can expect to see new surface coatings developed that will reduce debris while extending the life of the implant. Long-term studies 20 to 30 years after implantation will give us more feedback on what works best for which patients.