When I was in my late teens I snapped my ankle. I never had a broken ankle so I just thought it was really badly sprained and drove my motorcycle home, upon which my parents immediately diagnosed we had to go to the hospital.
I believe I was told I had all three ligaments snapped, and I chipped off some ankle bone that was screwed on and got surgery.
I was running in a walking cast in 4 weeks. Then I had several weeks (maybe 8 or something) of rehab which involved a lot of stretching and range of motion stuff.
It happened in spring. I was certainly doing full athletic activity pain free by the next fall no problem. I was playing both rugby and fencing. And that was in the mid 90s. I'd like to think things are a little better now in some ways.
Luckily I don't think I messed up my tendons much and didn't fracture anything real badly, but it was a pretty bad ankle injury.
So when I hear ankle injury I try to be optimistic. To be fair I didn't have to play at an NBA level and Gordon's situation seems worse than mine.
I think we need to wait for the MRI