I’ve recently torn my ACL and gotten knee surgery I

Patient: I’ve recently torn my ACL and gotten knee surgery. I use crutches everyday so far and I’ve started to notice that in the middle of my back, my spine aches if I bend it or even if I’m sitting straight up, it just hurts like a dull throb and it’s so uncomfortable. Is this happening because of the crutch or…? I’m 18 by the way.

Doctor: