As mentioned above,,the dr;s ussually want to do a series of blocks,,if you son doesnt have an entrapment,there are documented cases where the blocks thru the RSD into remission,,that would be the best case scenerio,,,,and as abasaki mentioned ,the fact that he had a 6 month remission from one block is great,,it is normal protocol to run a series of them first,and i agree with the above advice,,you dont want your son to have a SCS only if absolutly necesary..the rule of thumb is,,if a person is still in smp and not progressed to sip and he or she gets good [the longer the better result will be] from the blocks,that they will then be a prime candadate for a SCS,,,,,,,but your son has everything going for him,,he;s young,,youve caught it early,,and he is responding well to the blocks,,,,,,,thank the lord for this good news and praise his name,,,I hope and pray that another 1 or 2 blocks will do the trick,,,,one of my old pain management dr;s told me that he has had several go into remission by cutting the head of the snake[blocks] off early,,,,,,,,,,,,may the Lord bless you and your son,,,,,,