My father is in the middle stages of Alzheimer's and is having a very difficult time with mobility. He needs to have hip surgery (possibly replacement) however his doctors have recommended against it as they state that he wouldn't be able to handle the re-hab due to his memory loss. He's on a strong codeine-based medication and it doesn't seem to be touching his pain...this is his third "stronger" med for this. An assisted living/memory care move for him and Mom are in the planning stages...her mobility is just as bad, but hers is due to diabetes related neuropathy.
If he was my dad, I wouldn't do it. Assisted Living may take him as long as he is cooperative. If he is agitated or aggressive, AL will refer you to memory care. Sadly, couples are often forced to be in separate facilities when this happens.