There’s a phrase that was popular in the 80s stating anyone with a great butt had "Buns Of Steel" (due to the workout video of the same name). According to testimony in the Jackson family’s wrongful death lawsuit against concert promoter AEG, the late Michael Jackson had buns of steel, but in a different way.

Testimony from Jackson’s former doctor, Stuart Finkelstein, revealed his bottom was completely scarred and hardened from years of drug abuse, via injecting potent pharmaceuticals into his buttocks to get high. Finkelstein stated under oath, "I attempted to give [Michael] a shot of Demerol [a painkiller] but his buttocks were so scarred up and abscessed that the needle almost bent."