Ah, Josephine! All the very best for your upcoming surgery. I hope it goes well and you make a sterling recovery.
You've been such a help to us all - now it's your turn! Get plenty of rest and feel free to complain to us - we'll always be here to listen! And we all care about you!
About crutches/walkers:
I came home to New Zealand from Canada using two underarm crutches, after my 11-year-old PKR failed suddenly. I was not supposed to bear any weight at all on my damaged knee. At the hospital in Quebec City, they measured me and fitted the crutches very carefully, warning me lots about the dangers of putting pressure on my armpits. (No. Someone my size and age cannot bear their full weight on forearm crutches!) They showed me how to use the crutches and would not let me leave until I had mastered the correct technique.
I had 2.5 months on those crutches before having my Revision to TKR and, so, developed confidence in them. When the staff got me out of bed the morning after surgery, they had me use a walker. I hated it, although it was useful to hang the catheter bag on!
The next day, the physio came along with forearm crutches for me. I have a weak left wrist and I felt that the forearm crutches were putting strain on it; I felt as though that wrist would give way on me and it made me feel unsafe. So, I said "no thanks" to the forearm crutches.
We had a little battle of wills (along with an explanation by the physio as to why underarm crutches could be unwise), but I explained that I already knew the possible dangers and my crutches had been measured and fitted for me when they were issued. (I already had calluses on my hands, but not under my arms!

)
I left the hospital using underarm crutches. After about a week, I graduated to using a pair of forearm crutches (with new rubber tips fitted) that my son had left behind - he has an above-knee amputation. A week after that, I started using 2 sticks. Later, just one stick, and then none.
As far as I can tell, in New Zealand, walkers are seldom used after TKRs, except for the first few days. Most people have the forearm crutches. There is a definite awareness of the potential for damage being caused by putting pressure under the arms if using underarm crutches.
Best wishes,
Celle