My left arm gets the abuse from the dumb stuff my right arm does. It holds the parts I'm drilling, hammering or installing. My osteo dr had little advice why my left wrist arthritis pain was worse than my right, even though I'm right handed. (Collagen does help, btw, NMA). Maybe it's that my left does the white-knuckle driving while my right does the shifting and eating...

Speaking of boosters: to those who haven't got the second Shingles shot yet: don't plan anything for a couple of days. "You may have a mild reaction" includes fever (103), sweating, weakness, nausea...etc etc etc). Then again, maybe someone misplaced a decimal point. My left arm is used to that kind of thing.