None of the older, more experienced guys at my gym do heavy squats or deadlifts and some have actually said to me it's not good for me in the long run. I think the emphasis is on the heavy part though... I'm not a big squatter or deadlifter and don't go for the big numbers. Soon as it gets too stessful I quit and lower weight/raise reps or change program.
Never gone for anything heavier than a 5 rep PB on squats (150kg) and I've only attempted a 1 rep PB on deadlifts a couple of times ever. A good example is today I'll be using 130kg for deadlifts - a weight pretty much everyone one here uses as a warmup!
As I'm no spring chicken myself I've been lifting almost 20 years and from drawing on my own conclusions I'd say too much volume is our biggest enemy. Joints and tendons take longer to heal.... especially of you're stubborn and persist with training through the pain and things get chronic.
I think painkillers are a bad idea, I never touch them.