G'day Eric I did a bad dislocation of the small bones in my wrist 6 mths ago skiing, the physio told me to do what I could, and I certainly couldn't do all of the exercises she wanted me to due to the pain. I used a good wrist brace for the start of the season and had to develop a way to roll onto the boat after capsise. I see your biggest problems are going to be snapping the sheet out of the cleat, pulling the sheet, some holding of the tiller. Then righting the boat can you climb back on using your elbows. If you can do that the pain will be what really tells you to stop so dont take pain killers before you go out and then sailing will be just more physio.
just my thoughts regards