Get them things replaced. If your cars suspension was metal on metal you'd replace the bushings!
I am now just 62 I had both knees replaced last August. Best thing I ever did! I was on 24/7 OTC pain meds and could sometimes not walk 100 yards. Now no pain meds and walking is not a problem. It's A LOT of hard work and you HAVE to do the exercises and stretching. the full recovery time is a year so if you are a candidate for doing both at the same time do it, otherwise you will have a 2 year recovery
