Yes, this has happened to me also, but not for a very long time. Your post reminded me of it. In the early days of my MS, my arm would lock up at the elbow when I shoveled snow. I would get nerve pain on the top of my forearms also. I still get the nerve pain once in awhile, but not as bad. No joint locking for years.
That was one I had forgotten until I read your post.
I wonder if anyone has ever had something my neuro called "vibrosity". I had that in the middle of a big exacerbation. I would bump the front of my thigh and I would get a sensation like the vibration of a tuning fork. It was actually kind of neat, which translates into; it didn't hurt. Maybe at the time I just needed something to laugh at. It was about ten years ago when I was just becoming aquainted with MS and had a lot of fears that it was going to end my career in law-enforcement in it's infancy. It did, but I moved on and got over that a long time ago. Lucky for you guys I did, I was really whining about that back then.