Chronic pain can wear a person down in ways that are hard to explain. It can show up in the back, neck, shoulders, joints, hips, head, or hands. It can change sleep, mood, movement, work, relationships, and the simple routines that used to feel automatic. What makes chronic pain especially frustrating is that the painful area is not always the full story. A shoulder may ache because of a local injury. Low back pain may begin after lifting something heavy. Knee pain may follow