Why does my shoulder ache?

Shoulder pain is a common problem, especially in senior citizens. — TNS

If you find yourself rubbing your shoulder after reaching up to take a coffee mug off the shelf, hammering in a nail just over your head or climbing into a pickup cab, you're among millions of adults – particularly those over 60 – with a shoulder issue.

Shoulder pain could be a sign of arthritis, tendonitis, a rotator cuff tear or shoulder instability.