Dear Dr. Lowell,
For over two years, my three fingers on my left hand have been numb. They are not completely numb, but the numbness never leaves. I went to a neurologist & he performed tests & ruled out carpal tunnel syndrome. He said he would like to do an MRI, but could not unless I had shooting pains, which I do not. Nevertheless, I did not go back. Is this a major problem? Are there ways to cure it without surgery? I did not want to go through a lot of unnecessary things to find out there was no way to cure it, but do not want to have more problems in the future if left as it is.
Numbness in the hand can be caused by pinched nerves in the neck, since the nerves that supply sensation to the hands come out of the neck, and they can get pinched as they exit. However, hand numbness caused by the neck is usually associated with some kind of pain in the neck, or pain travelling down the arm into the hand. This is not always the case, however. There are some rather uncommon situations in which there can be a painless numbness in the hand which is caused by compression of the main spinal cord in the neck. This is painless because the spinal cord itself, just like the brain, has no pain sensors of its own. A dysfunction of the spinal cord produces only numbness or weakness in an extremity.
If the numbness that you are experiencing is only in your thumb, forefinger, and middle finger, and you have no weakness, then the most likely diagnosis is carpal tunnel syndrome. If the test for carpal tunnel is negative, then I think that an MRI of your neck would be in order to rule out the possibility of spinal cord compression. However, I once again would remind you that this condition is rare.
Progressive or serious weakness in the arms caused by spinal cord compression is a problem that won’t go away by itself. It should be treated surgically to remove the pressure on the spinal cord. Unless you are experiencing severe numbness or weakness in your arm, the condition is not serious, and you should be able to leave it alone if it is not bothering you a whole lot. Surgery can also be considered on an elective basis if your pain/numbness is persistent and you are just tired of living with it. The surgery would be done wherever the nerve compression is coming from. If it’s from the neck, we remove whatever is pinching the nerve, usually a ruptured disk or a bone spur. In carpal tunnel syndrome, we make a small incision in the palm to relieve pressure on the nerve there.