"Doctor, my arm went numb." This sounds like a clear communication, doesn't it? Most physicians would interpret this complaint as meaning that the skin of the arm lacked full sensation. But maybe the patient meant that the arm had extra sensations, like tingling or shocks. Or even that the arm's muscles became weak.

In my community-based practice of neurology, I have discovered that the word "numb" can have any of these three meanings, alone or in combination. And the medical implications of the different meanings can be quite different. For example, if the arm became weak, it might mean the patient suffered a stroke that damaged the brain. If, instead, the arm tingled, it might have been due to a disruption of the circulation or peripheral nerves in the arm itself, as from sleeping on it wrong. So in order to get the diagnosis right, I need to quiz the patient about the exact meaning of "numb."

"Numb" is one of three words at risk for medical misinterpretation. The other two words are "dizzy" and "normal" -- good, everyday English words, to be sure, but words that require further explanation when used in a medical context.

The problem with the word "dizzy" is that two patients might complain of dizziness and mean entirely different things. In fact, there are four different symptoms that I've heard patients use the word dizzy to describe: spinning or other sense of motion, also known as vertigo imbalance/unsteadiness lightheadedness verging on passing out

The distinctions are not trivial. If I assume, when patients report dizziness, that they mean a spinning sensation when they actually mean they're lightheaded, then I'll probably make an incorrect diagnosis. Lightheadedness (and verging on passing out) are more likely due to blood pressure or heart problems, while vertigo is usually about the inner ear and its connections. If my diagnosis

So what could be the difficulty with the word "normal," a word that seems so utterly, well, normal? I'll illustrate the problem with a patient's question: "Isn't it normal, Doctor, for a person to be confused at the age of 80?"

The answer is yes or no, depending on what the word "normal" means. This word's dual meanings often go unrecognized. A usual non-medical meaning has to do with how common or typical something is. But, particularly in a medical context, normal can also refer to whether or not something is healthy. So if the question is if it's common or typical for an older person to be confused, the answer is yes. But is confusion healthy? No. The presence of confusion means something has gone wrong. Examples include a brain infection, Alzheimer's disease or even side-effects from a medication, all of which are unhealthy.

So here's a quiz: Is it normal to be numb or dizzy? Hopefully, you caught the pitfalls in the question. Non-medically the answer is yes -- these symptoms are very common in a person's lifetime. But medically the answer is no -- while not necessarily serious, these symptoms signal an unhealthy condition.

(C) 2006 by Gary Cordingley