I fractured the end of my thumb playing football of all things.
My thumb was put in a splint for 6 weeks & when it came off I couldn’t use trigger shifter as the muscle was so weak. After a few weeks exercising my thumb it was good to go.
All in all I was off the bike for 8 weeks. My advice is don’t try to do too much too soon or you will put back your recovery.
On another note second ride back on the bike I crashed into a gorse bush & had to have 3 stitches in my tragus, then 2 rides later some Bint pulled out in front of me & I rode into her passengers door !!!