The Canadian giants are on the road in the US just now, on a trip they've stopped short of calling their farewell. It's been thought that drummer Neil Peart's desire to be with his family could be the deciding issue - although he's also suffering from tendonitis.

But Lee tells Classic Rock's Paul Elliott: "For Alex the arthritis is not a small thing. If anything is going to mean we can't tour any more like we used to, it's more than likely going to be the arthritis - because that's something that will directly affect his ability to play.

"If I was going out on stage and I couldn't play the way I want to, or the way I've played in the past, there's no way I'd want to do it. I wouldn't want to go out there and be a shadow of my former self."

He adds: "it kind of hurts me to see him when he's having a bad day, physically. He's one of my oldest and dearest friends. And when he's been at rehearsal and he's not playing his best, it's not nice to see your friend suffer like that. This thing is in the back of his mind, and he's afraid of it."