I'm 55 and THRILLED I had the surgery. I recommend it to everyone (need it or not).

BTW, they WILL do 2 knees at the same time, but generally not 2 hips - which is why I had to wait for my 2nd hip.

What is said about knee replacement is to get both done at the same time. It's supposedly pretty painful, and once you do one, you won't want to get the other one done. (I'm not sure if this is the lever you want.)

OTOH, I strongly recommend the surgery. I spent a lot of time in hospital and rehab talking to people who had hips and knees done. Quality of life is much improved, and the daily pain is gone.... And lifespan for the replacements is 15-20 years, depending on how you abuse them.

Make sure he goes to a good hospital that does them frequently.