@SusanEllen66 The "20-25 year life span" is no longer accurate. New materials, and revision techniques, have made this obsolete.
My hip implants were done in my 50's, and are 20 years old. According to my ortho, who x-rayed them in May, they will probably be good for another 15-20 years. (I'm hoping for longer because I don't want to face revision at 90 or 95.) If I had known, I would have had them done 10 years earlier instead of suffering, thinking I was "too young."
My nephew's Dad had his replacements before age 50 - the doc said "Why suffer? If you need revision in 20-25 years, the technology will just be that much better." My friend's son had both hips and both knees done in his 30's - he may need revisions in 10 years, but has been able to function without pain for may years.
Unfortunately, in many places, this enlightened attitude has not arrived.