Guess we won't know what exactly happened until and if we get something 'official'. All we can do is wish him a speedy and successful recovery.
It's too bad we may no longer see him personally doing some of his own minor stunts for VII (jumping, running, etc), but he could surprise us.. after all he's probably more machine now than man ;)
Edit: Very cool 5 images. Falcon cockpit is looking really good. It's amazing to see the snow speeder and Tie Interceptor. Interesting new small ship with the curved surface.