I broke my thumb while dismounting my SV650 about 25 years ago, boot caught on seat, ended up kicking the bike away from my and of course put my hands down just in time before falling on my face.
left hand, fingers free, though the cast disabled my wrist as well as the thumb, but I could still operate the clutch, and barely slide my casted hand thru the sleeve of my Aerostich, so I was still able to ride