cut on lower part of left thumb - unable to flex thumb

Recently while cutting some raw chicken, I cut across the lower bone on my left thumb.  It became infected and the pain shot all the upper my forearm.  I went to the emergency room for treatment (a Tetanis shot,antibiotic shot,hand x-ray).  The doctor said she could not see any injury in my thumb. I informed her that I was unable to move my thumb.  She informed me that after taking the antibiotice by mouth for seven days along with 600 moltrin; that my thumb should be o.k.  To date, I can't move my left thumb.  It is bent and I can't flex it at all.  

Can you give me some suggestion on treatment (hand surgeon, etc) thank you!

[Dr Vinod]

Yes the Physician was right that there is no problem with the bone, but you might have had a cut to the tendon or the muscle which is inserted to the base of the thumb phalangeal bone. You have to check this out near an orthopaedician who would check your movements and give you the right advice. Take care!