The Progression of Total Knee Arthroplasty From 1993-2013
The Progression of Total Knee Arthroplasty From 1993-2013
Early technologies in TKA were limited by catastrophic aseptic failures and accelerated wear rates. With poor outcomes, surgeons were reticent to expand the scope of arthroplasty, which limited the eligibility of patients to receive device implantation. As surgical techniques and implant designs improved, so too did clinical outcomes, which resulted in a significant increase in the demand for total knee arthroplasty during the 20-year time period from 1993 to 2013.
Bang et al. used data from the Nationwide Inpatient Sample (NIS) to estimate yearly procedural counts for total knee arthroplasty from 1996–2005. They found that the number of primary total knee replacements performed in the United States (US) increased from 253,123 cases in 1996 to 497,419 cases in 2005. Revision total knee surgery, likewise increased accordingly from 21,264 cases in 1996 to 39,985 cases in 2006. Furthermore, total knee replacement volume was found to be significantly higher than total hip replacement in every year sampled.
Over the past 2 decades, the demographics of a total knee recipient have evolved to include more patients from varying demographic groups. Modern demographic data for knee arthroplasty in 2004 showed a mean patient age of 67 yr, with 64% of patients being women. In 60% of TKAs the primary payer was Medicare, and 87% of procedures took place in an urban hospital setting. Additionally, the authors recognized a steady increase in arthroplasty performed on patients between the ages of 40–64 yr over the course of the study.
Kurtz et al. used data from the National Hospital Discharge Survey (NHDS) to quantify the rate of primary and revision knee arthroplasty from 1990–2002 based on patient age and sex. They found that the number of both primary and revision knee arthroplasty procedures increased 200% over the course of their study. The rate of primary procedures increased in all age and gender groups studied. However, the largest rates of increase for both men and women were in patients younger than 65 yr. Revision burden, defined as the ratio of revision procedures to the total number of primary and revision surgeries, was calculated for all patient groups. The mean revision burden for knee arthroplasty was found to be 8.2% over the course of the study. The revision burden for knee arthroplasty showed no significant change over the 13-year study period in all but one patient group.
Additionally, it is important to note the evolution of patient demographics as well as the procedure load over time. Kurtz et al. again used NHDS data in 2007 to predict usage of TKA from 2005–2030. They estimated that the demand for primary knee arthroplasty would increase by 673%, resulting in 3.48 million yearly procedures by 2030. The revision rate was forecasted to have a similar increase of 601% by 2030. These authors cautioned that previous studies have likely underestimated the demand for knee arthroplasty, in addition to trained surgeons capable of fulfilling such demands.
Epidemiology
Early technologies in TKA were limited by catastrophic aseptic failures and accelerated wear rates. With poor outcomes, surgeons were reticent to expand the scope of arthroplasty, which limited the eligibility of patients to receive device implantation. As surgical techniques and implant designs improved, so too did clinical outcomes, which resulted in a significant increase in the demand for total knee arthroplasty during the 20-year time period from 1993 to 2013.
Bang et al. used data from the Nationwide Inpatient Sample (NIS) to estimate yearly procedural counts for total knee arthroplasty from 1996–2005. They found that the number of primary total knee replacements performed in the United States (US) increased from 253,123 cases in 1996 to 497,419 cases in 2005. Revision total knee surgery, likewise increased accordingly from 21,264 cases in 1996 to 39,985 cases in 2006. Furthermore, total knee replacement volume was found to be significantly higher than total hip replacement in every year sampled.
Over the past 2 decades, the demographics of a total knee recipient have evolved to include more patients from varying demographic groups. Modern demographic data for knee arthroplasty in 2004 showed a mean patient age of 67 yr, with 64% of patients being women. In 60% of TKAs the primary payer was Medicare, and 87% of procedures took place in an urban hospital setting. Additionally, the authors recognized a steady increase in arthroplasty performed on patients between the ages of 40–64 yr over the course of the study.
Kurtz et al. used data from the National Hospital Discharge Survey (NHDS) to quantify the rate of primary and revision knee arthroplasty from 1990–2002 based on patient age and sex. They found that the number of both primary and revision knee arthroplasty procedures increased 200% over the course of their study. The rate of primary procedures increased in all age and gender groups studied. However, the largest rates of increase for both men and women were in patients younger than 65 yr. Revision burden, defined as the ratio of revision procedures to the total number of primary and revision surgeries, was calculated for all patient groups. The mean revision burden for knee arthroplasty was found to be 8.2% over the course of the study. The revision burden for knee arthroplasty showed no significant change over the 13-year study period in all but one patient group.
Additionally, it is important to note the evolution of patient demographics as well as the procedure load over time. Kurtz et al. again used NHDS data in 2007 to predict usage of TKA from 2005–2030. They estimated that the demand for primary knee arthroplasty would increase by 673%, resulting in 3.48 million yearly procedures by 2030. The revision rate was forecasted to have a similar increase of 601% by 2030. These authors cautioned that previous studies have likely underestimated the demand for knee arthroplasty, in addition to trained surgeons capable of fulfilling such demands.
