Neither deca or NPP will repair any fiber, they only help a bit with water retaining which helps a bit about lubrication your joints.
Whenever we run AAS usually few things can happen faster than the natural ratio, things like; gain of strength, gain of muscle mass, faster recover of the muscle tissue, etc...
Things like that leads you to training more and heavier, also sometimes when you cut you loose more water than normal as well.
Tendons and ligaments don't grow like muscles and can get dry or sore due to over stress
Add to the equation the fact of your body probably will be fighting to all the inflammation process you have on your system due to growing and the poisoning your liver is fighting as well and you can really fuck up your joints if you are not giving enough nutrients/rest to your body or even if you have a crappy form whenever you are working out with heavy weights
The gear is only a small part of the equation if you don't look at everything together
I mean everything like nutrition, work out plan, gear you take and if you are doing the exercises correct, you probably will waste time, money and health using AAS
And trust me I wasted lots of time, money and health already with AAS without almost no results
As far as I know there is no gear to fix joint pain, I suggest you to try a physiotherapist or a trainer who can help you to work around your issues, that may help you more than add compounds to your cycle