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 Tendon inflammation and swelling prevents the tendon from sliding easily in the tendon sheath, which causes triggering of the finger as it snaps to flex or extend.  Risk factors for trigger finger include diabetes, rheumatoid arthritis, and repetitive movements.