Knee Surgery Good for the Greater Good

Knee replacement surgery overall benefits higher than costs to society

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Patients usually see a big difference in quality of life after knee surgery, but the procedure does not come cheaply. An average knee replacement surgery costs around $20,000.

But the overall benefit from surgery may be higher than the cost, according to a new study that put a number on both direct and indirect benefits from the surgery.

The study estimated an average benefit to the society of more than $38,000, resulting in an average savings of more than $18,000 per patient who undergoes surgery.

"Ask your doctor about osteoarthritis treatments."

The study was conducted by Lane Koenig, PhD, healthcare economist at KNG Health Consulting, along with colleagues.

The aim of this study was to examine the impact of knee replacement surgery on both patients' lives and on society in terms of costs and savings.

Sometimes, a knee joint that has been damaged due to conditions such as osteoarthritis or rheumatoid arthritis can cause a lot of pain and loss of movement. Knee replacement surgery replaces the damaged tissue with a new artificial joint.

As the US population ages and obesity rates rise, the number of knee replacement surgeries is increasing. The researchers estimate that more than 3 million knee surgeries will be required in the year 2030, up from 600,000 in 2009.

The researchers looked at data from insurance claims and also collected data about surgery outcomes from patients. Patients were asked about their ability to move around and perform certain tasks.

Data was collected from a population of 185,813 adults to calculate the indirect benefits from being more mobile and pain-free. They also looked a patient population of 74 patients who had undergone knee replacement surgery to calculate the indirect costs of surgery and the benefits obtained if the surgery is successful.

They then conducted an analysis of the data from patients (close to 60,000 patients) who underwent knee replacement in 2009 to find out the total costs versus savings to the patient and to the society as a whole following the surgery.

After looking at the data, the researchers found that the average direct cost of knee replacement surgery to the patient was around $20,635.

On average, for a patient, the costs of undergoing surgery are offset by an average savings of $39,565 per patient for the society.

Most of the savings (85 percent) to the society came from increased employment and earnings that occurred when the surgery had a good outcome. The rest of the savings came from fewer missed workdays and lower disability payments made to the patients.

Thus, the average lifetime societal benefit (savings minus costs) was $18,930 per patient.

Overall, the researchers concluded that total knee replacement surgery was a cost-effective method for treating patients with late-stage osteoarthritis. For the 600,000 knee replacement surgeries conducted in 2009, the savings to the society over the patients’ lifetimes would be around $12 billion, since the society would gain an average of $18,930 per patient operated on.

"We know that when a knee replacement is done on patients at the appropriate time, it adds tremendous value to their lives. It gets them back to work and back to their families. It improves their quality of life and allows them to be productive and active again," said John R. Tongue, MD, past president of the American Academy of Orthopaedic Surgeons (AAOS), in a press statement.

"This study allows patients to see the big picture of the effect on their daily lives and in the long term," said Dr. Tongue.

"The benefit of successful treatment of bone and joint conditions in the long term is known by the patients who've been through it, but these data offer evidence on the societal effects that will add to the conversation people are having about improved, cost-conscious health care," said Dr. Koenig in the same press statement.

According to President of Payer+Provider Syndicate, Adam Powell, PhD, “When considering the financial impact of medical interventions, it is crucial for us to take a societal perspective as well as a healthcare system perspective. A treatment that increases healthcare costs may still be cost-saving to the society if it reduces costs outside of the healthcare system."

The researchers pointed out several limitations to their study. First, patients who reached a full-benefit state were considered to have the same quality of life improvement as those who did not reach a full-benefit state. Also, questions about improvement in mobility and pain were asked two years following surgery and this may have affected the patients' memory of specific benefits or issues.

It must be noted that the savings of $18,930 are average savings to the society. It does not mean that every patient who undergoes knee replacement surgery will have the same benefits. The benefits and results of knee replacement surgery vary from patient to patient.

“This study shows that while providing knee surgeries may increase healthcare costs, doing so ultimately is financially beneficial to society, as it enables people to continue working for more years and to not require as much assistance. When we put a monetary value on the improvement in the quality of life of the people receiving the knee replacements, their total societal value will appear even greater,” said Dr. Powell, who was not involved in this study.

The results of the study were published August 21 in the Journal of Bone and Joint Surgery.

The study was funded by the American Academy of Orthopaedic Surgeons who commissioned KNG Health, a consulting company and its partner, IHS Global Inc. to prepare the study.

Review Date: 
August 21, 2013
Last Updated:
August 28, 2013