Please tell me what causes your shoulder bone to "thicken" over time?

Oldy but bony!: As we age (sob!), joints can get thicker and bonier from chronic changes over time, as with changes from degenerative arthritis, which is really common (double sob!). There are also diseases where too much calcium is deposited in the bone. See your doc and find out why your shoulder bone is changing size. As Bette Davis wisely said, "Growing old ain't for sissies!" Exercise preserves function.