Numbness can be caused by various nerves in the upper extremity. The physical exam and certain tests can help figure out if a peripheral nerve is involved causing the symptoms.


The nerves that innervate the hand come from the neck. There can be a problem in the neck that causes symptoms into the hand. There are several nerve roots that make up the nerves in the hand. In the neck, the nerves come out from small opening between the cervical (neck) vertebrae. These nerve roots are numbered by the levels that they originate from.


The main peripheral nerves of the upper extremity come from the neck and run all the way down the upper extremity into the hand.

Raymond Severt 2013