Like most bones, 6 weeks technically. I was doing gentle riding still with splint after less than that. Was index finger on one hand and little fingers on the other. Just had to brake with different fingers 😀 . I couldn’t not ride without going crazy. As I say, gentle rides, just to get out.
If you’ve got a splint and talk of an op, there’s a chance there’s ligament damage. That’s what I had on the index finger. That was way more of a concern to the doctors than the other hand which was a simple fracture. The ligament had basically torn the bone away a little, and it had to be kept in place with a splint for a long time day & night, and then still longer just at night. Was longer than 6 weeks. Then took a fair bit of physio to get the thing to bend again.