Featured Research

from universities, journals, and other organizations

2.5 million Americans living with artificial hip, 4.7 million with artificial knee

Date:
March 14, 2014
Source:
American Academy of Orthopaedic Surgeons
Summary:
Two related studies have found a growing incidence of adults younger than age 65 undergoing total knee replacement and total hip replacement surgeries, and a potential under-utilization of these procedures in some segments of the population.

More than 7 million Americans are living with an artificial (prosthetic) knee (4.7 million) or hip (2.5 million), which may have significant future implications in terms of the need for ongoing patient care, according to new research presented at the 2014 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS). Two related studies also found a growing incidence of adults younger than age 65 undergoing total knee replacement (TKR) and total hip replacement (THR) surgeries, and a potential underutilization of these procedures in some segments of the population.

While numerous studies have quantified the incidence rate of TKR and THR and in the U.S., there is very little information about the number of patients actually living with a prosthetic knee or hip. In "Prevalence of Total Hip (THA) and Total Knee (TKA) Arthroplasty in the United States," researchers reviewed THR and TKR incidence rates, mortality rates and relative mortality rates (the difference in survival between THR and TKR patients and the general population), over a 40-year time period, to estimate 2010 prevalence rates according to age, sex and time since surgery.

Among the study findings:

  • Approximately 0.8 percent of Americans are living with a hip replacement, and 1.5 percent with a knee replacement.
  • More women are living with prosthetic hips and knees than men.
  • Prevalence of THR and TKR among adults age 50 and older is as high as 2.3 and 4.6 percent, respectively.
  • The prevalence of THR rises to nearly 6 percent by 80 years of age. The prevalence of TKR rises to nearly 10 percent by 80 years of age.
  • The states with the highest number of THR and TKR patients are California, Florida and Texas; the two states with the lowest numbers are Alaska and Hawaii.

"This study shows that around 7 million Americans have a hip or knee replacement," said Daniel Berry, MD, professor of orthopaedics at Mayo Clinic and the senior author of the study. "This large number highlights how these operations have kept a substantial part of our population mobile despite severe arthritis, something that wouldn't have been possible before these technologies were available. These relatively high prevalence estimates also highlight the significant ongoing need to care for all of the patients with total hip and knee replacement. These prevalence estimates are within the same ballpark as coronary heart disease, and much higher than heart failure or stroke. To put these numbers in perspective, there are roughly one and a half times as many people living with a hip or knee replacement in the U.S. as people living with heart failure."

Individuals with total hip and knee replacement often are complex patients with multiple chronic conditions," added William A. Jiranek, MD, professor of orthopaedics, Virginia Commonwealth University School of Medicine. "They all need continuing medical attention and some need further surgical attention over the years of having a replacement. As "there are no guidelines to define long-term management of these individuals….our prevalence estimates are vital to agencies charged with planning for the provision of health care services."

A recent study published in the Aug. 21, 2013 Journal of Bone and Joint Surgery, and conducted by health economists, has confirmed that TKR is a cost-effective treatment for patients with end-stage osteoarthritis. By modeling indirect savings of the individual returning to the work force after surgery, researchers found that the lifetime societal net benefit for patients undergoing knee replacement averages between $10,000 and $30,000.

In the related studies presented at the annual meeting, "Trends in Total Hip Arthroplasty in the United States: The Shift to a Younger Demographic" and "Trends in Total Knee Arthroplasty in the United States: Understanding the Shift to a Younger Demographic," researchers conducted a retrospective review of 2000-2009 hospital discharge data on TKR and THR patients from the Nationwide Inpatient Sample (NIS) Healthcare Cost and Utilization Project (HCUP). Researchers looked at procedural rates, gender, race, age, payer type, length of stay (LOS), discharge disposition and revision burden for each year, stratified by age. U.S. National Census data was used to calculate rates for each procedure per 100,000 U.S. populations within each age group.

Among the study findings:

  • The incidence of TKR increased by 120 percent from 2000 to 2009: 188 percent for patients ages 45 to 64, and 89 percent for patients ages 65 to 84. The incidence of THR increased 73 percent from 2000 to 2009: 123 percent for patients ages 45 to 64 and 54 percent for ages 65 to 84.
  • The number of revision total knee replacement (RTKR) procedures increased 133 percent, and the number of revision total hip replacement (RTHR) procedures by 27 percent.
  • The increase in TKR and THR patients is primarily due to "the disproportionate growth in the rate of utilization among younger patients, and secondarily by overall population growth."
  • Medicare was the primary payer for 63.3 percent of all TKRs and 58.2 percent of THRs in 2000, and 54.7 percent of TKRs and 52.8 percent of THRs in 2009.
  • The proportion of TKR patients discharged with home health care increased from 19.1 percent in 2000 to 40.5 percent in 2009; and the number of THR patients, from 18.9 percent in 2000 to 40.8 percent in 2009.
  • Race and gender distribution have remained relatively stable for TKR, RTKR, THR and RTHR.

"Our data demonstrate that increases in the number of primary and revision knee and hip arthroplasties have been driven predominately by increased procedural rates, as opposed to population demographics," said lead study author Jacob M. Drew, MD, of the University of Massachusetts Medical School.

In addition, "while shifts in age strata seem to be ongoing, race and gender distribution have remained relatively stable for both TKR and THR," said Dr. Drew. "This suggests that well-documented racial disparity in total joint replacement (TJR) persists, and that there remains a substantial population in whom TJR is underutilized."


Story Source:

The above story is based on materials provided by American Academy of Orthopaedic Surgeons. Note: Materials may be edited for content and length.


Journal Reference:

  1. David Ruiz, Lane Koenig, Timothy M. Dall, Paul Gallo, Alexa Narzikul, Javad Parvizi, John Tongue. The Direct and Indirect Costs to Society of Treatment for End-Stage Knee Osteoarthritis. The Journal of Bone and Joint Surgery (American), 2013; 95 (16): 1473 DOI: 10.2106/JBJS.L.01488

Cite This Page:

American Academy of Orthopaedic Surgeons. "2.5 million Americans living with artificial hip, 4.7 million with artificial knee." ScienceDaily. ScienceDaily, 14 March 2014. <www.sciencedaily.com/releases/2014/03/140314093737.htm>.
American Academy of Orthopaedic Surgeons. (2014, March 14). 2.5 million Americans living with artificial hip, 4.7 million with artificial knee. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2014/03/140314093737.htm
American Academy of Orthopaedic Surgeons. "2.5 million Americans living with artificial hip, 4.7 million with artificial knee." ScienceDaily. www.sciencedaily.com/releases/2014/03/140314093737.htm (accessed October 22, 2014).

Share This



More Health & Medicine News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) Is your child ready? Video provided by Working Mother
Powered by NewsLook.com
U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

Newsy (Oct. 22, 2014) Now that the U.S. is restricting travel from West Africa, some are dropping questions about a travel ban and instead asking about visa bans. Video provided by Newsy
Powered by NewsLook.com
US to Track Everyone Coming from Ebola Nations

US to Track Everyone Coming from Ebola Nations

AP (Oct. 22, 2014) Stepping up their vigilance against Ebola, federal authorities said Wednesday that everyone traveling into the US from Ebola-stricken nations will be monitored for symptoms for 21 days. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Doctors Help Paralysed Man Walk Again, Patient in Disbelief

Doctors Help Paralysed Man Walk Again, Patient in Disbelief

AFP (Oct. 22, 2014) Polish doctors describe how they helped a paralysed man walk again, with the patient in disbelief at the return of sensation to his legs. Duration: 1:04 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins