From arsenal.com- bits of the Emery press conference:

"on Welbeck going to hospital…
Yes, now he is at the hospital. The news is that we are going to wait - but we think it’s a serious injury

on if it’s an ankle injury…
It’s an ankle.

on how said it is to see Welbeck injured again…
Every injury is different. This [could] be a break of something in the ankle. It’s a different injury to others.

on if Welbeck’s future is here despite the injury…
He’s a very good person. His commitment with us is very big. He’s helped us with his behaviour, with his quality and his capacity. It’s a very big injury for him, for us, for all people who like and love him as a person."