Knee replacements are already being done outpatient with some patients. You will still stay overnight but it is still considered outpatient if you stay less than 24 hours. Surgery and recovery has to go well, you need a driver and you need someone at home to help you for a few days.

Living by yourself, it is highly unlikely you would be allowed to go home the next day. More likely you would go to a rehab center for a few days for proper care, initial PT and to learn how to deal with your limited mobility on your own when you do go home.

I had major hip surgery to repair a fracture. Could not put weight on that leg for 3 months so it could heal properly. I live alone and after 5 days in the hospital, I spent another 7 days in rehab center before I went home. I needed that to regain strength and learn how get around without damaging the hip until it healed. Simple things like getting in and out of the shower or tub, getting in or out of a car, getting in and out of bed or standing up from a seated position. I sure did not want to screw my hip up and have to go through surgery again.

Knee replacement is not that restrictive but you dang sure do not want to get in a situation where you damage the repaired knee.

Lol they want you out of there before the spine blocker wears off. I would have went home the same day but I was the last surgery and had to stay till next morning. I was under home health care so physical therapy started there for two weeks with a therapist coming every other day and me doing it 5 to 6 times a day. Mine would swell up tight before noon and wouldn't bend much after that. After 8 weeks probably working a clutch on a tractor did more good on breaking it free than therapy. Check on the Dr.'s pain medicine scheduling. Mine changed his a month before I had mine done and it was weak. I've had rod and screws in the back and it was a cake walk compared to knee replacement. But if you need it do it. I'll have to do the other one soon. Hope to put it off till next Jan. Don't have time for it now. Turkeys to kill,mushrooms to pick and crappies to catch.

i had both of mine replaced October 2019 and can honestly say i don't remember the pain. I was in the hospital 5 days on morphine but not much. I cant take strong pain killers so mostly Tylenol every 8 hrs
rehab was painful at first but the sooner you get them bent and straight the sooner the pain leaves. My outcome was great, no more sleepless nights, back doesn't hurt, feet don't hurt. going down steps is the only thing uncomfortable at times.

I would do it again if need be.

I get very sick anesthia an after 2 surgery's I told I look white like go pass away ,

I had a knee replacement in 2012. Had the operation on a Monday afternoon and came home the following Thursday afternoon. The most pain I had was when I forgot and started up a step with the replaced knee. Quick learner, never did that again. Had to remember to step up with the knee that was not replaced and to step down with the one that was. Had some good pain medicine. Pain does not help the healing process, so don't be afraid to use it as directed. Therapy will be what you make it. I had the therapy exercises that I could do at home. Even If I had therapy that day, every evening I did the exercises and it paid off. Talk to the doctor and get some exercises that will build up the muscles, so following the operation, you will be ahead by having your muscle tone. I was off work for 7 weeks. My job required me to be in and out of a pickup truck several times a day. When I went back to work, I got back into my normal daily activities and it all went well.

Had my right knee done in January 2020. There have been some complications even after tons of physical therapy.
Living alone in the country after my wife passed away a year before I had a feeling I could go through a lot of friendships
before the six weeks of not driving had passed. As a hint, if you are on Medicare and stay in the hospital for three
consecutive midnights Medicare will pay for Nursing Home and Physical Therapy. I spent nearly seven weeks in the home
and never received a bill. (staff was calling me Uncle Roy by the time I was released)
When I transferred to the home the drug store let my pain pill prescription fall through the cracks. I spent four days doing therapy
with extensive pain but grit and bear it.
Every case is different!
Roy