I had the surgery 4 weeks ago so I am still in the cast for 2 weeks, followed by 6 weeks in a splint that is removed only for PT. I also had carpal tunnel release on that hand as long as they were in there. It doesn't appear to me that the thumb is going to be much of a problem - I have virtually no pain in it now, even when the cast has been removed for refitting. The area where half of the tendon was removed was achy for the first couple of weeks but is perfectly fine now. However the truly irritating part has been irritation of the carpal tunnel incision by the cast. I seemed to have a reaction to the padding used for the waterproof cast and have felt like pins were sticking into my wrist every time I moved the hand at all. After several cast changes, today I went back to conventional padding and that fabulous invention - "Press And Seal". I am much more comfortable now, even though I will need to keep this cast dry for another two weeks.
When I had the surgery the hand surgeon warned me that it would be a nasty recovery. I thought "Nasty, my eye! I've had two total knee replacements this year and sailed through. This thumb couldn't possibly be too bad." Well, he now has my eye! It was a beast for the first many days - a combination of needing pain killers every 4 hours (more than for the knees) and the incredible irritation of losing the thumb function. Let me tell you, I got tired of wearing night clothes or sweat pants in the below zero Minnesota weather. And a certain undergarment is out of the question. But all this is temporary - unlike the irritation and personal limitations from the pain if you don't do the surgery. One suggestion - DO NOT GET OUT OF BED FOR AT LEAST A WEEK (again, more than for the knee replacements). And, KEEP THE ARM UP ON HIGH PILLOWS every moment you can. It seems impossible to do, but recovery is massively easier if you find a way to shut down all activity in the beginning.
I pulled as many months as I could out of having a cortisone shot in the thumb. Sometimes it really resolves the whole problem for a long period of time so I wanted to give it a try. But ultimately, it was just easier to go through a couple of "lost months" than continuing dealing with pain and weakness. Just think, I may be able to open a jar of pickles again!
I worked with horses professionally for decades. The motivation for both the knees and the thumb has been to get back on a horse - and being able to trust my bod to work. I really think this goal that absolutely requires good joints has put the temporary issues of surgeries in perspective. Good Luck to all of you considering the "anchovy" surgery