@johnbishop @iceblue The ulnar nerve is also affected by Thoracic Outlet Syndrome, and it's possible to have entrapment in multiple places. I sleep on my side too and would make my symptoms worse by bending my elbow. When I first noticed what turned out to be TOS, my entire arm was going numb when I slept or tingling and it was not the arm that I was laying on. The position of my neck also affected the numbness and tingling in my hand.