My aunt had an amputation for vascular disease. She was in so much pain, she couldn’t walk, but the actual reason was that after three tries, her doctor decided the vascular problem couldn’t be corrected surgically, and was probably going to eventually lead to tissue necrotizing. At the point she was at, they could salvage a lot on her lower leg, and basically, she’s be able to walk again, after being in a wheelchair for six months.
Which was, in fact, the case, albeit, she needed physical therapy.
One thing they did was check her into the hospital 48 hours before the surgery, and do some nerve blocks, while cutting back on the general pain medication she was taking, but using some other things-- I don’t remember all the details.
The purpose was to have her completely out of pain for a significant amount of time, like, an entire day-- a whole 24-hr stretch. IIRC, this was to prevent phantom pain. If she was in a great deal of pain at the time of the surgery, her brain might continue to experience the pain, but if the pain went away, then there wouldn’t be any pain in the missing part of her leg.
It apparently worked, because she was in less pain than she thought she’d be after surgery-- albeit, she felt exhausted for the first two days. But after she had healed well, she was never in pain, and has never experienced phantom pain-- she does experience “phantom limb,” though, when she wears her prosthesis. She says when she puts weight on it, her brain registers the pressure on the bottom of her “foot.” I guess it has something to do with the neurons that were once dedicated to her foot still being in place in her brain, and still receiving signals.
She’s done really well. She never did get to the point where she could walk without a cane or a Lofstrand crutch, except around her house, but considering that she wasn’t walking at all before, that’s pretty good-- and she was IIRC, in her early 50s when this happened, so there were other things involved, like the beginning of arthritis in her knees, and her ankle in her other leg. Probably her hips too.
It’s been at least 20 years, and she’s still walking, She’s had a knee replacements, and one hip replacement, and still walks with a cane, but just a cane, not a walker, or two crutches.
She has said many times that she has no regrets.