Sorry to hear of the Neuropathy there with you Dad.
My wife is currently dealing with Charcot's Foot Neuropathy. Not sure if this is the same thing you are having to work with or not.
From what I understand about it, which is somewhat limited, there may be some swelling of the foot or feet and/or legs depending on the situation. There is usually no pain noticed, which is part of the Catch 22 with this condition, but the results can be complicated and dangerous if not taken care of.
In my wife's case, her left foot swelled up to 4 times it's normal size and had a redish/pupleish coloration. Of course we freaked as we didn't know what this was at the time, but later found out that if you pack the foot and /or leg off with ice and keep it elevated, per the doctors instructions, the swelling will usually subside.
The main problem with this condition is that you can actually break bones without even knowing it due to the lack of pain. The results can be deformation of the bones as they try to heal and other, more serious concerns, can enter into the situation. Please check with your doctor on this and read up on it as much as you can. That is very important to do.
I don't want to alarm you about this, but it can be very serious if steps are no taken soon!
In most cases of treatment, there is usually a cast involved for quite a few months, if the situation calls for it and do not put any pressure on the foot and/or leg, such as ANY KIND of standing or walking. This is a "pain" ( pardon the pun) to have to do, but is paramount to help remedy the situation. Healing will not happen correctly if the person walks or stands on it too much!!
Check a search engine, such as Google, and you'll find all kinds of info on the subject.
I was very unaware of the complications that can arise if this is not taken care of properly and I won't go into that here, but reading as much as possible on the subject will help in your quest for answers.
I hope all turns out well for you and yours there with this and bare in mind that others, like my wife, are dealing with this too.
Take care.....TMCD Tennessee......