Three main nerves give sensation to the skin of the arm and hand as well as control muscle contraction in the forearm, wrist, hands and fingers. If these nerves get irritated or entrapped anywhere between the spine and your fingers you may have numbness (hand falling asleep), weakness, tingling, burning, pain or tightness in the arm, hand, or fingers.

The Median Nerve has seven entrapment sites starting at the base of the
neck and then travels down and gives sensation to the thumb, pointer finger and your middle finger.

The Ulnar Nerve has eight entrapment sites starting at the neck and then
moving down the arm. Irritation of this nerve will give problems in the pinky finger and ring finger.

The Radial Nerve has six entrapment sites starting at the neck and moving down the arm. If the nerve is entrapped at one of these sites you will feel it in the back of the hand, thumb, and pointer finger.