Who has said its career threatening? What exactly is the injury, do you know? Almost certainly it is a load of rubbish someone made up because they were bored, turned into a rumour and for some reason people love stories like this because they think it could be big news. Sure we will see him playing soon.
It's some niche injury called something like "athletes toe". It's soft tissue damage to the base of the toe and if you're really unlucky it could be recurrent. It's very painful to run or turn on (given that our toes are the most important part for acceleration). If it's recurrent, it can then threaten your career. I think it's one of those injuries where they still don't know exactly how to cure it every time. This obviously makes it quite difficult to be sure it will get better.
I very much doubt that RvW is perma-crocked, but all I'm saying is that this rumour has probably got about because someone has realised that it's a possibility and the injury is worse than it initially sounded.

and spellchecking? Apologies - I didn't mean it rudely.