When I got my total hip replacement five years ago, they told me to expect it to last 10 to 15-years. Since I'm only 69 years old, I'm hoping to outlive my implant by a long shot. Have there been any changes in the predictions in the last five years?
More long-term studies are available now comparing implants used in hip replacements than ever before. Studies comparing results based on age, activity level, and different types of implants are ongoing. Most surgeons still use give patients 10 to 15 years as the expected survival rate of the average implant. Your age at the time of the surgery and your activity level since are both key factors in how well the implants hold up. In younger adults (less than 75 years old), the type of implant does make a difference. Cementless stem implants seem to have better survival rates and lower revision rates when compared with the loaded-taper cemented stems. Patients who are older than 75 show no difference in outcomes based on stem type. These statements are based on the results of a large study done in Finland. In this same study, they compared the survival of various acetabular cups (socket side of the hip). There was no overall difference between cemented and cementless cups after 10 years. Based on age, adults less than 75 years old did better with the cementless cups. There were fewer cases of revision because of loosening of the cup. In the older group, cementless, hydroxyapatite-coated press-fit cups were less likely to loosen or need revision. When problems did occur with the cups, there was one main difference between cemented and cementless cups. Cups with a polyethylene (synthetic or plastic) liner showed excessive wear in the cementless group under age 75. The large number of wear-related revisions of cementless cups points to the need for an improved (wear resistant) design. When reviewing the overall results of the total hip replacement (both stem and cup components), the cementless implants had the better outcomes. The 10-year survival rate was 90 per cent or better for all total hip groups. When broken down by age, there was no major difference in the risk of revision among the groups.