I got beat up by a tree a few years and turned one wrist into what the doc described as Rice Krispies. I had a fixator on for six weeks followed by a cast for four more.

Once the cast was off I started doing PT once a week for ten weeks. The PT was to both strengthen my hand and break the tendon that had bonded to the break loose. It was about six weeks in when the tendon finally broke loose. There was a loud snap when it happened.

A thumb may not be as bad. Once the pins are out do the PT. Things will probably come back faster if you do more then just the PT sessions. It will hurt like a sonofabitch. Pain is good!!

Good luck!