Mortality, Cost and Health Outcomes of Total Knee Arthroplasty in Medicare Patients

MENLO PARK, Calif., March 27, 2013

In the study of Medicare records, Exponent scientists examined the effects of joint replacement among nearly 135,000 patients with new diagnoses of osteoarthritis of the knee from 1997 to 2009. About 54,000 opted for knee replacement; 81,000 did not.  Three years after diagnosis, the knee replacement patients had an 11 percent lower risk of heart failure.  And after seven years, their risk of dying for any reason was 50 percent lower.

The theory behind knee replacement, said the study's lead author, Dr. Scott Lovald, Senior Associate at Exponent, is that treating this degenerative condition will allow a return to normal activity and ultimately improve overall quality of life.  "At the end of the day, we're trying to figure out if quantity of life increases as well," he added, noting that the team was conducting a similar review of Medicare data on the long-term benefits of hip replacement surgery.

"These patients had improved survivorship and reduced risk for cardiovascular conditions." "For an incremental cost of less than $3,000 per year, total knee replacement may reduce the risk of mortality by half."

A subsequent review of Medicare data on long term benefits of hip replacement surgery is showing that Total Hip Replacement  (THR), or hip replacement, is associated with reduced mortality, heart failure, depression and diabetes rates in Medicare patients with osteoarthritis. The results of the study were presented at the 2013 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS) held in Chicago March 19-22nd. 

View the full abstract here:
http://www.arthroplastyjournal.org/article/S0883-5403(12)00528-1/abstract

Exponent, Inc. is a multidisciplinary organization of scientists, physicians, engineers, and business consultants performing in-depth investigations in more than 90 technical disciplines.  The company investigates and analyzes failures and accidents to determine their causes and prevention and evaluates and solves complex human health and environmental issues.  Exponent is certified to ISO 9001.