Nandrolone is known to improve collagen synthesis, thus it's good for joints, connective tissues, and healing in general. I assume you've permanently damaged disc(s), and it's unlikely that nandrolone will help with that issue 25 years after the injury. I've had ruptured discs, fusion surgery, degenerated discs, crushed vertebrae etc, and I've done every therapy you can think of (Chiro, massage etc). IMO, Nandrolone works best for joints in long cycles, 16+ weeks. I like to run 150mg-200mg per week with my TRT, but because I'm on TRT, I don't have to worry about HPT shutdown and recovery. This is a good therapeutic dose, without side effects, and it keeps my joints and nagging injuries feeling good. If you're running a cycle cycle or TRT, throw in some Deca or NPP, but do not run Deca by itself(without Test). My 2 cents, good luck bro