MIAMI, Florida—The US healthcare system should brace itself for an exponential increase in the number of primary and revision joint arthroplasties and their associated costs, warns Sunny Kim, PhD, a researcher with the Robert Stempel School of Public Health at Florida International University, in the April 15th issue of Arthritis Care & Research.¹

"The results of the present study demonstrate that the burden resulting from hip and knee joint replacement is not only substantial, but also increasing at an alarmingly steep rate," Dr. Kim writes. "Public health education is critically important to reduce the proportion of people who are overweight/obese as well as manage arthritis at earlier stages. …[T]he health care community should be prepared for this upcoming demand of primary/revision surgical loads and its economic burden on government and private insurance companies."

Dr. Kim identified joint replacement cases throughout the US from the Nationwide Inpatient Sample (NIS) and analyzed increases in surgeries and costs between 1997 and 2004. In 2004, there were ~431,485 primary knee replacements performed, up 53% from 2000. There were 225,900 primary hip replacements performed in the US in 2004, up 37% for the same period.

If current trends continue, ~600,000 hip replacements and 1.4 million knee replacements will be performed in the year 2015, Dr. Kim predicts.

Increase pronounced among baby boomers

In 1997, ~60% of primary hip replacements and 69% of primary knee replacements were performed on individuals between the ages of 65 and 84. Although elderly patients were the main recipients, the number of joint replacement surgeries among patients ages 45 to 64 increased excessively in 2004: hip replacements increased 71% and knee replacements increased 83%.

"This trend may be explained by both increases in the overweight population at earlier stages and the change in their expectation of quality of active life," Dr. Kim suggests. As patients in this age group are not yet eligible for Medicare, the increasing number of replacements they undergo will increase the burden on private insurance. That trend will also increase the need for future revision surgeries.

Between 1997 and 2004, hospital charges for primary and revision joint replacements and surgeries increased faster than the rate of inflation, the study showed. While Medicare continued to provide the principal source of payment, compared with other sources of payment, the relative burden decreased. The burden on private insurance more than tripled in the same period from $1.1 billion to $3 billion for hip replacements and from $1.46 billion to $4.64 billion for knee replacements.

"Wake-up call" report paves road for solutions

"Studies like this are a wake-up call that [total joint replacements are] tremendously valuable procedures and in order to provide benefit, we need to make strategic investments in a national joint registry and basic science," said Joshua Jacobs, MD, professor and chair of orthopaedic surgery at Rush University Medical Center in Chicago.

"The solution is not to restrict [these surgeries] as there are probably populations that are already underserved," he told MSK report.com. "It is one thing to focus on costs and another thing to think about the cost of not doing the procedure. These are some of the most cost-effective procedures in all of medicine in terms of how we can return people to gainful employment and functioning."

Enter a national joint replacement registry. "The real costs start to skyrocket when we talk about revision surgery because the implants fail and have to be re-done or become infected," he said. In these cases, savings can be had by creating a national implant registry.

"A national joint replacement registry can identify factors associated with success and/or systems that are not performing as well so we can modify them. We should also make an investment in research to improve the longevity of the replacements, [understand] the biology of loosening [prostheses], and learn how to make materials more and more durable."

Reference

1. Kim S. Changes in surgical loads and economic burden of hip and knee replacements in the US: 1997-2004. Arthritis Care Res. 2008;59:481-488.