Hello. When i was 25 i had Necrosis a vascular and the doctors tried to save my bone, cutting a bit of bone and adding it to the femur head. It did not worked and it got infected. So the doctor cut my femur head and i was with no femur head 12 months.
After that , i had a successful life with my left hip replacement, the right one is another story 🙁
Asking about mobility if the doctor wont put a temporal hip and you are with no bone like i was, i can tell you that you will be able to do everything but with crotches. Mobility was very good. I used to swim 2 k per day, drive, had a partner, all pretty good. Just being careful of not tripping over that is all.
I hope this helps