Dale Earnhardt Jr. learns of injuries he never knew he sustained

Dale Earnhardt Jr.'s battle with concussions throughout his Monster Energy NASCAR Cup Series driving career are well-documented, at least some of them. He sat out two races in 2012 because of concussions, and then, he missed the second half of the 2016 season as he endured a lengthy recovery from additional concussions. Recently, he discovered he sustained additional injuries he didn't find out about until a recent visit to a doctor.

At the urging of his wife, Amy, Earnhardt visited his doctor because of chest pains. To his surprise, sometime during his driving career, he sustained a broken sternum and a broken rib. He detailed the discovery through a series of tweets Thursday.

"Oversharing a bit here. But I learned something crazy the other day,” Earnhardt [@DaleJr] tweeted. "Was having chest pains. Sharp. Really bad. Wife encouraged me to get it checked out. My doctor suspected Costochondritis. That is inflammation of the sternum and ribs….

"Eventually this sent me to a specialist. They put me through several test to rule out any concerns with my heart. And the eventual diagnosis was [as my family doctor suspected] Costochondritis…

"But at the end of our conversation this doctor asks me, ‘When did you break your sternum?' Had no idea is was ever broke. He shows me an X-ray and says that it was broke at some point as well as a rib. Now I can’t stop wondering what wreck might have done it.”

Earnhardt retired from competition as a full-time Cup Series driver after the 2017 season with one of the reasons he cited for the retirement being his concussions. He remains co-owner of the JR Motorsports team in the NASCAR Xfinity Series and contest one Xfinity Series race as a driver last season and plans to run the Xfinity race at Darlington Raceway in late August. Since his retirement as a Cup Series driver, he has moved into the TV broadcast booth for NASCAR race coverage on NBC Sports.