I don't know why my physio didn't suggest it to me earlier but I have stumbled upon jigsaw puzzles for therapy. The repetitive movements of sorting pieces has done my lymphedema arm the world of good....
I do like the 500 piece ones as they are of a size that can fit on the table and I can still reach my laptop to have a break. I did a 1000 piece one which wasn't too bad but took longer to do and I did a 1500 piece which was rather a nightmare of sorting pieces over and over to find the right ones for the right spot. I have just started a 500 piece round one which is rather interesting but a beggar to fit the pieces as its not a standard cut.