Knee surgery for PWD?

My husband should have had knee replacement surgery well before he was diagnosed with Alzheimer's but he kept saying they were fine (they weren't). So he didn't. After the diagnosis, and as his walking deteriorated , we tried the cortisone shots but his arthritis was so far gone they did no good. I knew how hard the recovery from the surgery was, having watched my cousin the weeks after the surgery and felt that getting him to do the p.t. would be impossible, plus the effect of the anesthesia on the dementia would be bad (I read all the literature on this; it clearly is bad). So now he can barely walk a few blocks, slow and shuffling, though I make him walk every day to keep what mobility he has. It makes life even harder, the dementia and the physical impairment. Looking back, maybe I should have pushed for the surgery when he was in the MCI stage, but that's water under the bridge. He's now more or less stage 6, needs help with all ADLs, teeters on the three steps in our house, and walks about snail speed. But it's also hard to separate the effects of Alzheimer's on his gait (not knowing where his body is in space—not perceiving that the carpet and the floor really are just one continuous suface, not being able to take bigger steps) from the really bad knees. There is a procedure we looked at which supposedly gives pain relief for a year or two—genicular artery embolization—but I decided that the actual procedure too stressful so we didn't do it. But look into it if you are in an urban area. Good luck!