Carpal Tunnel surgery - complication?

I had my left hand operated on 5 weeks ago, a carpal tunnel release. I had the right hand done in May and haven't had any problems.
In my left hand, I have no numbness or tingling, and I have full feeling, but my thumb will not extend fully. I can't stretch it out, I guess towards my chest if I were holding my hand in front of me. I have almost full strength to grip, but I can't extend it. I can extend it manually with my other hand, but it moves back towards my hand when I let it go.

Is this a "normal" side effect, or did the surgeon do something wrong? Of course I showed it to him, he kept feeling the muscle area at the base of my thumb and asked if I wanted physical therapy. I asked if it would get better and he said it "likely" would. I don't know if I believe him.

I also posted this in orthopedics before I saw this group! Please help!

[Arti Sharma, M.D.]

Hello,
Without a clinical valuation I may not be able to determine the cause of your symptoms. From your symptoms it seems that you are having some muscular problem and it looks unlikely to be due to neural origin. You should consult your operating surgeon and discuss if physiotherapy would be helpful or not. Depending on the clinical examination results and response to physiotherapy you may need further evaluation .Do keep me posted on how you are doing. Best luck and wishes!