Prevalence of Total Hip and Knee Replacement in the United States.
BACKGROUND
Descriptive epidemiology of total joint replacement procedures is limited to annual procedure volumes (incidence). The prevalence of the growing number of individuals living with a total hip or total knee replacement is currently unknown. Our objective was to estimate the prevalence of total hip and total knee replacement in the United States.


METHODS
Prevalence was estimated using the counting method by combining historical incidence data from the National Hospital Discharge Survey and the Healthcare Cost and Utilization Project (HCUP) State Inpatient Databases from 1969 to 2010 with general population census and mortality counts. We accounted for relative differences in mortality rates between those who have had total hip or knee replacement and the general population.


RESULTS
The 2010 prevalence of total hip and total knee replacement in the total U.S. population was 0.83% and 1.52%, respectively. Prevalence was higher among women than among men and increased with age, reaching 5.26% for total hip replacement and 10.38% for total knee replacement at eighty years. These estimates corresponded to 2.5 million individuals (1.4 million women and 1.1 million men) with total hip replacement and 4.7 million individuals (3.0 million women and 1.7 million men) with total knee replacement in 2010. Secular trends indicated a substantial rise in prevalence over time and a shift to younger ages.


CONCLUSIONS
Around 7 million Americans are living with a hip or knee replacement, and consequently, in most cases, are mobile, despite advanced arthritis. These numbers underscore the substantial public health impact of total hip and knee arthroplasties.
Department of Health Sciences Research (H.M.K., D.R.L., C.S.C., and W.K.K.), Department of Orthopedic Surgery (H.M.K. and D.J.B.), and Division of Rheumatology (C.S.C.), Mayo Clinic, 200 First Street S.W., Rochester, MN 55905. E-mail address for H. Maradit Kremers: maradit@mayo.edu.
Hilal
H
Maradit Kremers
Department of Health Sciences Research (H.M.K., D.R.L., C.S.C., and W.K.K.), Department of Orthopedic Surgery (H.M.K. and D.J.B.), and Division of Rheumatology (C.S.C.), Mayo Clinic, 200 First Street S.W., Rochester, MN 55905. E-mail address for H. Maradit Kremers: maradit@mayo.edu.
Dirk R
DR
Larson
Department of Health Sciences Research (H.M.K., D.R.L., C.S.C., and W.K.K.), Department of Orthopedic Surgery (H.M.K. and D.J.B.), and Division of Rheumatology (C.S.C.), Mayo Clinic, 200 First Street S.W., Rochester, MN 55905. E-mail address for H. Maradit Kremers: maradit@mayo.edu.
Cynthia S
CS
Crowson
Department of Health Sciences Research (H.M.K., D.R.L., C.S.C., and W.K.K.), Department of Orthopedic Surgery (H.M.K. and D.J.B.), and Division of Rheumatology (C.S.C.), Mayo Clinic, 200 First Street S.W., Rochester, MN 55905. E-mail address for H. Maradit Kremers: maradit@mayo.edu.
Walter K
WK
Kremers
Healthcare Cost and Utilization Project (HCUP), Center for Delivery, Organization and Markets (CDOM), Agency for Healthcare Research and Quality (AHRQ), 540 Gaither Road, Rockville, MD 20850.
Raynard E
RE
Washington
Healthcare Cost and Utilization Project (HCUP), Center for Delivery, Organization and Markets (CDOM), Agency for Healthcare Research and Quality (AHRQ), 540 Gaither Road, Rockville, MD 20850.
Claudia A
CA
Steiner
Department of Orthopedic Surgery, Virginia Commonwealth University (VCU) Medical Center, 9000 Stony Point Parkway, Richmond, VA 23235.
William A
WA
Jiranek
Department of Health Sciences Research (H.M.K., D.R.L., C.S.C., and W.K.K.), Department of Orthopedic Surgery (H.M.K. and D.J.B.), and Division of Rheumatology (C.S.C.), Mayo Clinic, 200 First Street S.W., Rochester, MN 55905. E-mail address for H. Maradit Kremers: maradit@mayo.edu.
Daniel J
DJ
Berry
D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000706:statistics & numerical data*; D019645:Arthroplasty, Replacement, Knee / Q000706:statistics & numerical data*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000453:epidemiology / Q000601:surgery; D020370:Osteoarthritis, Knee / Q000453:epidemiology / Q000601:surgery; D015995:Prevalence; D012111:Residence Characteristics / Q000706:statistics & numerical data; D017678:Sex Distribution; D014481:United States / Q000453:epidemiology