We all know Rafa is the most dominant force ever to set foot on a tennis court. He would've won so much more slams if he was healthy, it's sad really. Probably one or two CYGS.
And it's not his style of play, being a defensive, high intensity player doesn't automatically mean you get knee problems. That's just bad luck. Rafa is just about the only one I can think of with severe knee issues on tour, is he the only one to do a lot of running?
No. It is his style of play. I'm no doctor, but if it's not the knee, it's gonna be something else. The way Nadal plays, hurt his body. The harder he plays, the worse the injury he'll get. Seeing how successful he is, it's a trade off that worth it, IMO.