Didn't we all know he'd find some excuse not to sing?
According to the Chicago Sun Times, Perry said, "My other hip is just not feeling right. My fans deserve to hear my best. And if I can't lean on my hip while I sing, I just can't see how I will sound like I did in 81. I plan on getting hip replacement surgery right after the World Series. This way, I'll be ready to sing the next time the White Sox win the big series."