I had a terrible bout with my shoulders and arms. Doctors were absolutely no help so I gave up on that. First my shoulders and arms just started to feel tired when I was driving. But then I started having like electrical flashes that started from my shoulders and ran down both of my arms and went clear to my fingers. And all the muscles in my arms just locked up. All I could do was just sit there until my muscles unlocked. And that cramping caused the muscles to hurt worse. And the more they hurt the more I had the electical sensation. It was awful. Lasted for months. Better now but my arms still get really tired easily. And riding in the car can be awful sometimes. This one is so wierd I hate to even ask about it. But it really bothers m e - and really affected my lifestyle for months. Am hoping it never comes back like that again.