More specifically, the methylcobalamin form of B12 is recommended, as it has been shown to be the most effective. Taking B12 gives you a huge boost of energy while training, and more importantly, greatly helps your recovery.
Trigger finger (also called stenosing tenosynovitis) occurs when inflammation builds up within a tendon of a finger and causes it to involuntarily flex.  If the condition is severe, the finger gets stuck in a bent position and sometimes makes a snapping sound when forcibly straightened -- sort of like cocking the trigger of a gun, which explains the name. People whose job requires repetitive gripping are at higher risk of developing trigger finger, as are those with arthritis or diabetes. The treatment varies depending on severity and cause, which is why an accurate diagnosis is important.