One of World's Biggest Rock Icons 'Literally on Last Legs' After He Underwent Agonizing Surgery in Desperate Bid to Stop Him Being Left Totally Paralyzed

Robert Plant is feared to be nearing his final days after undergoing a brutal knee replacement operation.

The 77-year-old rocker admitted years of performing on stage has taken a savage toll on his body, leaving him with no choice but to go under the knife to get one of his joints replaced because he can no longer play sport.

Explaining why he has been using a walking stick, he said ahead of the procedure: "Ooh! I'm having a knee replacement next week."

"It's all the years of standing on stages. Well, either that or the tennis, which I can't play anymore," he continued.

A source said: "Robert is now recovering after surgery, but his inner circle is now genuinely scared he is literally on his last legs. Any surgery that major takes months to recover from for the healthiest person, but for someone nearing 80, it can take years off patients' lives."

Plant is putting a brave face on things, but he knows he is nearing the end.

"While talking about his pending surgery, the Led Zeppelin frontman paid tribute to the late Ozzy Osbourne following his death in July at the age of 76 following a years-long Parkinson's battle.

He praised the Black Sabbath wildman for the "world of craziness" he created.

Plant said: "I loved him. I thought it was great the way he took the seriousness out of everything, conjuring up a world of craziness for us all."

The rock veteran admitted their paths had rarely crossed over the years, but he still remembers their last encounter, despite it being decades ago.

He recalled: "The last time I saw him was probably about 1970 or '71. I had a Ford drop-sided pickup truck that I rescued from some brambles for nine quid. I took the whole thing to pieces and was working away underneath on one of those wooden boards, messing about. I looked out and could see a pair of cowboy boots with leather fringes. So I scuttled out and there was Ozzy. He said, 'What you doing under there? She'll be much better off if somebody else does it!'"

Plant recently explained why he turned down Tony Iommi's invitation to be part of Black Sabbath's farewell concert in Birmingham, which was held weeks before Osbourne died.

Plant admitted he isn't as keen to play huge stadiums anymore and prefers the "rich" intimate spaces where he's recently been performing.

He said: "I said, Tony, I'd love to come, but I can't come. I just can't. I'm not saying that I'd rather hang out with Peter Gabriel or Youssou N'Dour, but I don't know anything about what's going on in that world now, at all. I don't decry it, I've got nothing against it. It's just I found these other places that are so rich. For me, because I've been from a very questionable Live Aid to the O2, to Obama and the White House and all those things, I was beatified. I felt the tug of doing this – Saving Grace needed just to move on up in glory, as Mavis (Staples) would say. We've got to be very careful now that we make sure it stays closer to Bert Jansch than Axl Rose. The gigs are small enough so that if nobody wants to go, it's not the end of the world. And so, by having that laissez-faire, easy-going, whatever it's called – suicidal! – attitude, instead of doing the football stadium with some old mates, there it was: we were free. We could mess about."