Past Trends and Future Expectations for Joint Replacements

With the aging of America the number of adults having joint replacements in the United States is expected to go up. But how much has it increased in the last 10 years? And how much will it go up from there?

Finding out current rates and predicting future rates was the goal of this study. Another goal was to see how often joint replacements have to be revised or replaced. Groups of patients were analyzed based on age. Age groups included less than 45, 45 to 64, 65 to 74, 75 to 84, and 85 and older.

Total number of adults in each group living in the United States was calculated from the 2000 census. Data from the National Hospital Discharge Survey (NHDS) was used to count the number of total hip and knee replacements in the United States. Using these two figures researchers could find percentages of adults having joint replacements and revisions.

The results showed the number of total hip replacements has doubled in the last decade. Total knee replacements have tripled over the same time period. More women and more people over the age of 74 are having joint replacements than ever before. The number of revisions has increased with the overall increase in joint replacements. The relative amount has remained the same.

As expected, the results of this study confirm the fast growth in the number of joint replacements for adults of all ages. Increases are likely explained by the increase in obesity and osteoarthritis. Past guesses about future trends were based on the same number of implants being done each year. This study shows that future numbers are expected to rise at a rapid rate.



References: Steven Kurtz, PhD, et al. Prevalence of Primary and Revision Total Hip and Knee Arthroplasty in the United States From 1990 Through 2002. In The Journal of Bone and Joint Surgery. July 2005. Vol. 87-A. No. 7. Pp. 1487-1497.