Investigation of pain

Pain is a personal and subjective experience that cannot be detected with an X-ray, magnetic resonance imaging (MRI) scan, or physical examination. During our childhood, we learn what pain is through our own experiences of painful situations.

When investigating pain, the patient's story is therefore the most important diagnostic tool. At the same time, the pain does not always have to be experienced in the same place where it actually occurs. A classic example is patients with angina or heart attack, who often feel pain radiating to the left arm. This type of referred pain is also common in back problems, which means that you can experience pain in one place even though the cause is somewhere else.

To determine where the pain is really coming from, diagnostic nerve blocks are used. By numbing one area at a time and then having the patient describe the change in pain, the exact source can be identified. The anesthesia is done with regular local anesthesia, similar to that used in dentistry, and the effect usually lasts for 4–6 hours. When the anesthesia wears off, the pain returns.

To be able to determine the origin of the pain, at least two blockades with the same clear results are required.