Do not amputate that tail. That animal has some signs of MBD, the most tell tale one being his jaw structure. We have a similar animal (Twinkie) which has the same issue. Just let him be, MBD is irreverseable but you can slow down its progression. How old was this animal when you got him?
You can give him one or two completely caked insects a week with Repashy's Calcium Plus. You can also provide him UVB but go with a very low wattage bulb to avoid the temps getting too high. I'd recommend the exo terra 2.0 or 5.0 uvb tropical bulbs.
I also would not breed him if you had plans to. The problem with MBD is that you do not know if it is a primary disease of a healthy animal who did not always have the right husbandry or if he had a genetic problem which lead to less than sufficient absorption of vitamins which then led to MBD.