Dear Dr. Roach: For the past four weeks now, I wake up during the night because both of my hands have gone numb. I work my hands to get the feeling back and walk around my house for about 20 minutes as I do hand exercises. This happens two or three times during the night. During the day I have no issues. Im 69 years old, female, in good health and take no medicine. Is this cause for concern? Do you have any recommendations for me? Id appreciate your advice. J.C.
Answer: By far, the most common cause of intermittent hand numbness is compression of the nerves of the hand, which happens in one of three common places: the carpal tunnel of the wrist; the cubital tunnel of the elbow; or the cervical spine, as a result of a herniated disc or spinal stenosis. The exact location of the symptoms gives a clue to which of these three it is.
Symptoms that are worse on the thumb side of the hand, with a sparing of the little finger, are coming from compression of the median nerve in the carpal tunnel. These symptoms may also feel like they travel up the arm, as high as the elbow, and only occasionally higher.
Symptoms that go on the outside of the arm to the little finger are from compression of the ulnar nerve, and most people are familiar with this sensation from hitting that nerve, sometimes called the funny bone. Compression of the neck can cause symptoms that travel down the arm and shoulder, but may still involve the hand.
Not everyone with a nerve compression has symptoms that exactly match the textbooks, and I often hear that the entire hand is involved. Making a precise, anatomical diagnosis sometimes can be done by a careful exam, but a definitive diagnosis is made most commonly, not by an MRI, but by an EMG test of the nerves, also called a nerve conduction test.
Symptoms of carpal tunnel syndrome, which I think is the most likely diagnosis in your case from what information I have, often are worse at night. When we sleep, the wrists may flex (palms toward forearm) or extend (like you are stopping traffic), and this puts pressure on the median nerve. Keeping the wrist in a neutral position with a splint sometimes can stop the symptoms of carpal tunnel syndrome. People who dont respond to splinting may be treated with anti-inflammatories, but people with ongoing symptoms benefit most from a simple surgical repair. Surgery should be performed only on EMG-confirmed cases, in my opinion.
