Tissue Regeneration

Tissue regeneration takes a LOT of time, energy and resources and I don't know if it's possible to regrow an arm.

You would FIRST need to redress any and all nutrient deficiencies and unidentified infections, find a physician interested and talk to them about existing research into stuff like regrowing frog limbs.

I used to have a hole in my lung. I don't anymore.

And I've had decades-old scars improve. 

But that's minor compared to regrowing a lost hand.

Your DNA is like the code for the software telling the hardware what to design. It's still in there.

Concerns: 

1. You may theoretically need to reopen the wound to foster growth. Not my department. Talk to a REAL scientist who tortures frogs for a living.

2. It will require a LOT of resources for energy and for building blocks for new tissue. You will need the right nutrients.

3. Stem cells are probably a limiter here. Not my department. I'm a HOMELESS former homemaker.

4. MAYBE: hormonal stuff might help with the stem cell crap. Talk to someone smart with a PhD.

FYI: Chronic pain in old scar tissue is probably infection.

Strep and trypanosoma get into cartilage. Cartilage has NO blood supply and gets all resources in and waste removal out via osmosis.

Cartilage is the LAST tissues to heal AFTER ALL tissue around it improves.

You will want old cartilage healing before you go trying your Frankensteinian experiments on growing new limbs.