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.
In most cases, trigger finger is caused by repetitive gripping of the hand, or flexing of the thumb or forefinger. Those who are farmers, typists, industrial workers or musicians are particularly susceptible because they constantly repeat certain finger and thumb movements.