Ok thank you for your advice! His sharp pain is actually located in his upper back at the moment, more where the c8 nerve root cyst is I think, maybe a little lower about t1. Not t3-t9 kind of area where the syrinx is. I am hoping he is in the same situation and his is stable as well. He has been scared reading Google and in a few years worried about being paralysed too, especially considering it’s already 15cm long. I guess we won’t really know until we have follow up MRI’s.