I'm on business http://al4a.fun/ al-4a  Trigger thumb, or trigger finger as it's sometimes known, causes a person's finger or thumb to get caught in a locked position. <a href="http://www.mayoclinic.com/health/trigger-finger/DS00155" target="_hplink">According to the Mayo Clinic,</a> it can then stay stuck or straighten with a painful "snap." The cause? It depends. Trigger Thumb is the result of a narrowing of the sheath around the tendon in the problem figure, but that can be caused by a lot of things, including any activity that requires people to grip things frequently. Trigger Thumb is also more frequent in women.