It seems to be an ankle ligament tear.

I just twisted my ankle briefly at home, and now it's slightly uncomfortable when I walk. However, when I sit and change the position of my ankle, I experience unavoidable pain, so I went to the hospital for imaging and ultrasound. They suddenly told me to be hospitalized... of course, with a half-cast. They said I need an MRI to determine if surgery is necessary, which is quite difficult for me. My ankle has been somewhat problematic before, so I'm worried about my right ankle as well. I'm considering inpatient treatment, but I'm also wondering whether I should receive treatment for both ankles during hospitalization.