Thanks for all the good ideas; much appreciated!
Just to clarify, my dominant hand is okay. I can't run out to buy new bras, so have to make a back clasp one work, and I really cannot go without.
I fell quite hard, breaking both forearm bones; one of them was described by a surgeon as "shattered" and "in pieces." It was also grossly misplaced, making it immediately evident something bad had happened to the arm. (I sat on the sidewalk assessing matters before moving/letting anyone help me.) My face also met the pavement, and though it might make others turn in horror (nothing new there!), the real damage is to my arm. The surgery I had on Friday was the installation of a (permanent) metal plate and eight screws holding the wrist together.

