EAST LANSING — Does your insurance cover amusement parks? Maybe it should.
For years, David Wartinger's patients told him stories of passing kidneys shortly after riding roller coasters .
"Most urologists wouldn’t be surprised by this," said Wartinger, a professor emeritus within Michigan State University's Department of Osteopathic Surgical Specialties. Jarring motions and vibrations often jostle stones stuck on the outer area of kidney, enabling them to be passed.
But one patient's story prompted Wartinger to look at roller coasters more seriously. The patient told Wartinger he rode Big Thunder Mountain Railroad inside Disney World's Magic Kingdom three times in an hour and passed a stone shortly after each ride.
So Wartinger decided to test it himself. Alongside then-urology resident Mark Mitchell, Wartinger visited Disney in 2008.
He and Mitchell rode coasters with a backpack loaded with a 3D model of a kidney between then. Testing nearly 200 stones of different shapes and sizes, the pair found Big Thunder Mountain was particularly effective.
They found nearly 70% of stones were primed for passage when riding in the rear car at Big Thunder Mountain. Other carts on the ride weren't nearly as successful. The pair also tested Space Mountain and Aerosmith's Rock 'n' Roller Coaster, which failed to replicate Big Thunder Mountain's success.
Rough-riding coasters with quick turns are most likely to help stones move along, Wartinger said. Anyone looking to try Wartinger's method should avoid coasters with inverted loops or upside-down movement.
The potential cost savings for patients, employers and insurance companies are substantial, Wartinger said.
"We want to offer people something cheaper than a $5,000 Lithotripsy," he said, a procedure which breaks up large stones using ultrasound shock waves.
Coasters like Big Thunder Mountain won't work for everyone, Wartinger said. Much like a person's fingerprint, the inside of a person's kidney has a unique pattern. But for patients who know they have a small stone, recently had a larger stone broken-up or women looking to pass a stone before becoming pregnant, roller coasters are a logical proactive measure.
"I can tell you, if insurance companies want to save money, they’d cover visits to amusement parks," he said.