Racecar driver Stefan Wilson just revealed he needed some serious hardware put into his back -- including rods and screws -- to fix gnarly injuries he suffered during an Indy 500 practice crash last month.
The 33-year-old announced the update on his social media page late Wednesday night ... explaining docs had to affix two titanium rods and slew of other metal onto his spine in order to stabilize it after he had injured it on the Indianapolis Motor Speedway track on May 22.
Wilson said he couldn't even get out of bed -- let alone take steps -- following the surgery .