Had ACDF C6-7 several years ago and have done well for the most part. Lately however, I am having pain when I raise my left arm or do any repetitive motion in my left upper arm toward the front. I have inconsistent neck pain down to same shoulder. My left thumb keeps going numb. Having difficulty sleeping due to pain in arm and neck. Is this related to possible C5-6 herniation now or am I having secondary rotator cuff problems? I have stopped water aerobics due to pain in that arm occurring only after about 10 minutes.