You may use a certificate of citizenship or a naturalization certificate, to prove that you are a US citizen. But both the documents are not the same. A US citizenship certificate is granted to a person who acquires or derives citizenship from his US citizen parents.
Causes Of Twitching Of Fingers And Thumb. 1  Carpel tunnel syndrome causes twitching of muscles as the median nerve through the carpel tunnel becomes compressed. 2  A less disconcerting cause is muscle cramps that happen when small muscles in the hand contract.
1 Medical conditions that cause metabolic disorders, including low potassium, and kidney disease/uremia.  Twitches not caused by disease or disorders (benign twitches), often affecting the eyelids, calf, or thumb. These twitches are normal and quite common, and are often triggered by stress or anxiety. These twitches can come and go, and usually do not last for more than a few days.