Innovations in medical devices—such as artificial joints, pacemakers, and defibrillators—aren’t always beneficial in the long run. Small refinements in function or durability can come at huge cost to patients, with only minor improvements in long-term failure rates. To assess such trade-offs, a group led by Lisa G. Suter, M.D., assistant professor of medicine, developed a computer model that simulates patient outcomes with new devices, focusing on total knee replacement as a test case.
Someone who has a knee replacement in their fifties has an 18 percent chance the device will wear out within 20 years and have to be replaced again. But because of the higher risk of death among older patients, only 9 percent of those in their 70s who receive a knee replacement will need a second replacement. The Suter team reports in the November 4 issue of the New England Journal of Medicine that, as a group, older patients may not live long enough for longer-lasting devices to be worth their additional cost.
The researchers say their model can be easily applied to other device innovations to evaluate their true benefits.