Undesired muscle twitches in the arm, leg, shoulder ... Although it doesn't directly cause pain, pain is a relatively common complication for people whose ALS has progressed.

Brooke Eby was diagnosed with ALS, or Lou Gehrig's disease ... leg too — an official sign of progression. They checked my arm and saw it was twitching a little bit. That was enough for them ...

It further states, "ALS often begins with muscle twitching and weakness in an arm or leg, trouble swallowing ... "There's generally no pain in the early stages of ALS. Pain also is not common ...