Despite total knee arthroplasty becoming more prevalent in patients younger than 65 years of age, the main demographic of growth is still among patients older than 65, according to recent study data.
Researchers compared 1999 to 2008 U.S. census data for individuals 18 to 44 years old, 45 to 64 years old, and 65 years and older and the number of total knee arthroplasties (TKAs) performed annually in each age group. Per-capita incidence rates were calculated, and the growth rate in all demographics was determined.
Approximately 305,000 TKAs were performed beyond the number predicted by population growth alone in 2008. Patients older than 65 years of age represented the largest growing cohort, as 151,000 recorded TKA procedures and a per-capita growth rate from 5.2 to 9.1 procedures per 1,000 individuals was observed. Per-capita growth rate also increased from 1.4 to 3.3 procedures per 1,000 individuals among patients 45 to 64 years old.
TKAs were found to have increased 234% during the span of this study, from 264,000 in 1999 and approximately 616,000 in 2008, with fewer than 48,000 of the additional procedures able to be explained by population increase, according to the researchers.