Sometimes science moves in a mysterious way.
A few years back, urologist David Wartinger, a former Michigan State University professor, saw a student patient who he'd been treating for kidney stones. The patient had just returned from spring break in Florida.
"And he told me, doc, you're not gonna believe this, I went on a roller coaster and I passed a kidney stone. I got right back on the same coaster, I passed another stone. I got back on the coaster a third time and I passed three stones in a row."
Intrigued, Wartinger and a colleague, Mark Mitchell, fabricated a kidney using 3D printing. They filled the hollow part of the model with fluid and replicas of kidney stones and took the device on numerous roller coaster rides. Tests showed in many cases, stones passed out of the kidney, from 16% of the time to nearly 70%, depending on the ride.
Wartinger says sitting in the back of the roller coaster seemed to gets better results, because the kidney is being subjected to more force. And it is not necessary to choose the scariest ride at the amusement park. A "5" on a scale of 10 in scariness appears to work best, he says.
Wartinger think the intervention could help a lot of people, including those with small stones, those who have many fragments in their kidneys after shockwave therapy, and those who know they are prone to developing kidney stones.
"It could even help astronauts," he says. Astronauts are prone to developing kidney stones because bone loss increases calcium excretion, which can lead to kidney stones.