Hi...I wish I had known about your surgery.....and pray you have a smooth recovery......but you are doing too much too soon......and you have a syrinx !
Recovery for this can take time......and you can not rush it by doing too much with your activities...listen to your body....
Have you had EDS ruled out?
I get numbness and tingling in that area as well sometimes. I'll notice it after long car rides especially. I think its tethered cord. I've also had muscle spasms too, after a while they went away and haven't come back. I've had surgery, if I do too much my symptoms do come back, some symptoms more so than others.