Injuries occur in all kinds of people: young, old, healthy or debilitated. The good news is almost everyone recovers from injuries. Occasionally, when a significant injury occurs in someone with extensive underlying degenerative disease, acute pain can gradually evolve into chronic pain. Acute and chronic pains are two very different animals, and the evaluation, treatment and therapeutic goals are different.
Acute pain is what we’re all too familiar with. It is usually the result of tissue damage, such as a cut finger, burn or a turned ankle. The pain usually lasts until the tissue has healed to some degree. Even this, the simplest kind of pain, is a bit mysterious. A broken bone takes several months to heal but only hurts for a couple of weeks. Acute pain is usually pretty bad – it gets your attention and makes you stop doing whatever it is that makes you hurt. That, in fact, is the point. The body is trying to limit self-destruction. The body is hard wired to take care of itself – an interesting notion.
The medical evaluation of acute pain is usually pretty straightforward. Since tissue damage causes the pain, we just need to find the damaged tissue, figure out how badly the tissue is damaged, and finally, fix the damage. I may have slightly over-simplified, but you get the idea. We treat the body part that hurts.
Chronic pain is a considerably more challenging beast. There is no new tissue damage, or no tissue damage that wasn’t there two months ago, when you weren’t in much pain. So, from a doctor’s perspective, we don’t have anything to fix. Talk about having one proverbial arm tied behind our back. The next problem is that time is not our ally. Most acute pain lessens with time; strangely enough, chronic pain doesn’t. Next month or next year is likely to hurt just as much. The persistence of pain complicates its management because all narcotic pain meds become less effective with time and continued use. That means you get less relief from more medication. Medication doses can get scarily high chasing chronic pain – not a safe or productive pathway.
So, we look at the bigger picture. For your foot to hurt requires nerves in the legs, the spinal cord and a brain to get the message. If you’ve done a lot of treatment to the painful foot without benefit, it’s time to consider the nerves or the brain. When we try to block pain at the nerve, we might try a TENS unit to block transmission of the pain signal. This is an electrical device that uses pads on the skin to block pain with a low voltage electrical field. This actually works, and unlike pain pills, if it works it will keep on working. You don’t need a bigger machine or more electricity in the future. Doing a nerve block with an anesthetic or steroid is also an example of blocking the transmission of pain at the nerve.
Finally, we look at the brain. We have all said at some point, “I’m feeling no pain.” What we meant was our brain wasn’t working well enough to feel pain (usually the result of youthful overestimation of alcohol tolerance). Feeling no pain because you are unconscious also works in anesthesia. This is an imperfect solution as it is obviously hard to work while unconscious. That has prompted the search for medications that will selectively alter pain reception without sedation.
A surprising number of different classes of medications seem to do this for many patients. One of the first medications used “off label” for pain was amitriptaline, which is a 35-year-old tricyclic antidepressant. Many of the newer antidepressants called SSRIs (Prozac, Cymbalta and Celexa) have also been used with some success for pain management. The anti-seizure medications used for epilepsy treatment are also remarkably helpful for many patients in pain. Specific examples of these medications are Neurontin and Tegretal.
Chronic pain is a different beast than acute (new) pain. Some of the best approaches involve treating the transmission of pain at the nerve or the perception of pain at the brain. If you have a chronic pain condition, there are new approaches that may change your life.