Carpal Tunnel Syndrome is the most common cause of tingling of the fingers. This occurs when the median nerve because squashed under a thick compressive ligament in the wrist. It causes tingling in the distribution of the median nerve which is the thumb, the index finger, the middle finger and half of the ring finger.
Normally the little finger is not involved, but it can be difficult for people to know exactly which fingers are affected.
The tingling is often worse at night, and can wake people from sleep. They have to shake their hand to get relief.
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