He has injuries
This may not come as a surprise to anyone familiar with Johnny Knoxville’s work on Jackass, but the host and ringleader of the show’s troupe sustained a number of injuries over the years. On the set of the original Jackass television show, an ankle sprain sustained while performing a stunt forced Knoxville to wear a brace for most of the first season. While filming the first Jackass movie, he was knocked out cold twice: once during a department store match against pro boxer Eric Esch (better known by his stage name Butterbean) and again when he flipped a golf cart. Knoxville would later top that in Jackass Number Two, claiming he nearly died when a rocket blew up on him during a stunt. Yet no amount of concussions could compare to Knoxville’s greatest (or is that worst) injury: he broke his own urethra.
While performing a motorcycle stunt for the Jackass-inspired stunt show Nitro Circus, Knoxville was thrown from a motorbike. The 400-pound cycle landed on his groin, tearing his urethra. To this day, Knoxville must perform urinary catheterization on himself twice daily to prevent scar tissue from forming, and to keep the area clean. Needless to say, when Knoxville first began appearing on Jackass, he’d not even turned 30. Now age 45, the numerous injuries have started to add up, keeping him from performing his trademark stunts.