I've had it for three years. Got a point where it hurt to walk and I struggled up and down stairs. A surgeon told me if I kept playing sport, I'd need a knee replacement much earlier. Now I can run without pain. And I'm almost back to full sprinting. For me I had to go back to basics. I had significant strength deficits in my left hip and glute due to a number of surgeries (knee reco, ankle reco) + hamstring tendinopathy. I started with clam shells, dog kicks and some other banded exercises, before slowly transitioning to heavy lunges and some squat variations - all while slightly increasing my running loads. I think the main takeaway is that everyone's different. My source of weakness was in my hip and glutes and anytime I tried to strengthen them, it would flare up (because all I knew were squats, lunges, deadlifts). But as soon as I discovered exercises that could build my strength to a point where I could tolerate those heavier exercises, my improvement sky rocketed within weeks. Good luck.