The number of total knee replacement (TKR) surgeries has more than doubled over the past decade, bringing the total of Americans who have undergone the procedure at least once to more than 4.5 million, according to new research presented at the 2012 Annual Meeting of the American Academy of Orthopaedic Surgeons in San Francisco. Osteoarthritis (OA) continues to be the primary reason for having the surgery, and the greatest increase has been among younger patients.
To determine the number of Americans living with TKR, investigators used a computer model; US Census data; information from the National Health Interview Survey, the Multicenter Osteoarthritis Study, and the Osteoarthritis Initiative; and other national data and literature. Other key study findings include the following:
• Americans currently living with at least 1 TKR represent 4.7% of the population aged 50 years and older.
• The national rate of TKR surgeries is higher than those of congestive heart failure and rheumatoid arthritis.
• The prevalence of TKR is higher in women than in men (5.3% vs 4.1%), as is the prevalence of OA.
• Among persons aged 60 to 69 years, 4.1% of men and 4.8% of women have had a TKR surgery performed; among those aged 70 to 79 years, 7.1% of men and 8.2% of women have had at least 1 knee replaced.
• Ten percent of Americans aged 80 years and older are living with a TKR.
The large number of patients living with TKR may lead to substantial increases in revisions and complications, especially in younger patients, and the findings may help anticipate the future challenges related to TKR, including capacity for follow-up care, health care costs, and treatment access, it was noted. The study was funded by the NIH’s National Institute of Arthritis and Musculoskeletal and Skin Diseases.
In another study, researchers in Finland found that the annual cumulative incidences of partial and total knee arthroplasty increased rapidly over a 27-year period among 30- to 59-year-olds in that country. The greatest increase occurred in patients aged 50 to 59 years, and incidences were higher in women throughout the study period. The study was published in Arthritis & Rheumatism, a journal of the American College of Rheumatology.