The 61 year old has been hobbling around with the aid of a walking stick in recent weeks, but he insists he's on the mend and claims the ailment is nothing serious.
He tells RollingStone.com, "I've got a bit of a back issue, which is fixable. Thank the lord it's not happening while we're touring, because we'd be in a terrible state.
"But apart from that, everything is working fine. My voice... is wailing. It's strong, it's powerful... I'm 99.999 per cent working."
Halford is convinced the strain on his back is the result of his years of performing - as he's not the only ageing rocker to struggle with health issues.
Recalling a meeting with his old pals Lemmy and Rob Trujillo at the recent Golden Gods Awards in Los Angeles, he says, "I'm in the dressing room... and Lemmy's sitting across from me. Lemmy, God bless him, is going through heart difficulties.
"I'm comparing my ailments with Lemmy, and Rob, the bass player from Metallica, is doing these stretches... I don't know, these guys, a guitar is 15 pounds, and when you've got that slung around your neck for two-and-a-half hours a day - I think it's just degenerative. It's accumulative injuries.
"There's no difference from some aspects of sports. You think of a golf player just hitting a ball - 'Well, that can't be too strenuous.' But it is. It's incredibly strenuous when you do that for 40 years. You're going to have a few nicks and bruises."