Pain is defined by the International Association for the Study of Pain as an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage. I have experienced persistent pain for many years and know how frustrating and disruptive pain can be to your life. I also treat patients everyday with pain problems ranging from acute pain episodes to long standing complicated pain conditions. Below are 7 facts about pain that might surprise you, but also give you a deeper understanding about pain and how you can take the necessary steps to reduce it!
#1 Pain is a Top Down not Bottom Up Phenomenon
What does this mean?!? I think the easiest way to describe this is with an example: If you step on a nail you want to know about it so can take the nail out of your foot and perhaps get to a hospital or physician to get a tetanus shot or antibiotics. What happens when you step on that nail is a danger signal (what we in the medical world call a nociceptive signal) is sent through nerve fibers to your spinal cord then up to your brain. The danger signal then says to your brain "there is something going on in your foot what should we do?". The brain then analyzes the situation, taking into account tissue damage or potential tissue damage, the context, chemical reactions in the body, your thoughts and beliefs and many other factors, and then the brain decides "HOW DANGEROUS IS THIS REALLY?". If the brain determines the situation is dangerous enough you will have pain. The pain experience is your body's HARM ALARM.
Because the brain makes the determination of pain (not the part of the body where the pain is located) we say that pain is a top down phenomenon. There is no such thing as a pain signal or a pain pathway! There are danger signal or danger pathways but the brain ultimately makes the pain decision. Check out this great Tedx talk by professor and researcher Dr. Lorimer Moseley for a more in depth explanation.
#2 Tissue Damage and Pain are not always related
Another way to look at it is: If there is pain it does not mean there is tissue damage and if there is tissue damage it does not mean there is pain. Some examples of this are:
- Did you ever notice a bruise on your body and have no idea when you got that bruise? That is clear tissue damage (veins and capillaries have broken) yet you had no pain.
- We can randomly select 20 asymptomatic people off the street and place them in an MRI machine for their back. Odds are more than half of them would have some abnormality on the MRI. Anything from herniated discs to arthritis to bulging discs yet that have absolutely ZERO pain.
Both of these are examples of clear tissue damage yet the brain did not think it was dangerous enough to protect you so there is no pain. On the flip side there can be pain when there is no tissue damage or when injured tissues have completely healed. Think about the story Dr. Moseley told in the TEDx talk above. He was in excruciating pain after being scratched by a stick.
#3 Context matters!
I am sure you are thinking...what does this mean? The pain experience can be dependent on the context or situation you are in. Let's take another example: You sprained your ankle. We all know than when you twist or sprain your ankle it usually hurts! Let's look at that ankle sprain in 2 different scenarios: 1) You are walking in your home and you sprain your ankle and fall to the ground. Your brain will analyze this situation and most likely will want to protect you so will have some degree of pain. 2) You sprain your ankle in the middle of crossing the street and then look up and see a bus headed straight for you. Your brain will again analyze the situation and (hopefully) will conclude a bus hitting you is far more dangerous than an ankle sprain. As a result, the brain doesn't really care if you sprained your ankle and wants you to run as fast as you can out of the way of the oncoming bus...so no ankle pain. That does not mean you might not have some ankle pain after but at the moment of the fall you will have no ankle pain.
This is an example of the same injury but due to the context of that injury the pain outcome is completely different.
#4 Acute pain vs Chronic Pain
As I said above pain is there to protect you and is your harm alarm. This is exactly what is happening when you have an acute injury. It is completely NORMAL to have pain with an acute injury. Remember, we want to know if something on our body is truly injured so we can tend to it. More often than not acute injuries heal. The damaged tissues repair over time and and as a result you have less and less pain. The harm alarm slowly decreases in intensity, your pain decreases and eventually goes away. Again this is a very NORMAL progression for an acute injury.
The more complex type of pain is a chronic pain situation. Chronic pain as defined by the International Association for the Study of Pain is pain that persists well beyond the normal amount of healing time. The line between acute and chronic pain is about the three month mark. Usually, by three months the acute injury should have healed and the pain eliminated. In some people the pain persists well beyond this three month time frame and that is when things get tricky. If the tissues are healed why are you still having pain? Like I said above pain is a top down phenomenon and tissue damage is not necessary for pain. Your nervous system (brain, spinal cord, nerves) is running the show when it comes to pain...especially with chronic pain conditions. Your nervous system loves you so much that it is being overprotective....just like the over protective parent!
Another way of looking at chronic pain is the the nervous system is now more sensitive. Because of this increased sensitivity of the system is takes less to create the danger signal that is sent to the brain. During an activity, even though your tissues are no where near being damaged, the nervous system is so sensitive that it will send the danger signal way too early. Then your brain will analyze the situation and given it is now used to protecting you (even when it is not necessary) you will have pain. This is how you can continue to have pain even when there is no tissue damage or your tissues have healed.
#5 Should I Take an opioid?
Before we talk about the use of opioids I think it makes sense to define what an opioid is first. The definition of an opioid from the Merriam Webster dictionary:
any of a group of endogenous neural polypeptides (as an endorphin or enkephalin) that bind especially to opiate receptors and mimic some of the pharmacological properties of opiates —called also opioid peptide
a synthetic drug possessing narcotic properties similar to opiates but not derived from opium; broadly
Most people are more familiar with the second definition of an opioid as a synthetic drug so we will start there. People are often prescribed an opioid drug after a surgical procedure, following an accident with serious damage to the body or often for common pain problems like low back pain. If you just had surgery or an acute injury then an opioid may work quite well for short term use to help control pain. In my opinion this where opioid use should stay: for short term pain relief after surgery or serious bodily harm. The problem with opioid use is when it is prescribed for long term use or for those with chronic pain conditions. Science has shown that when used for long periods of time, opioid medication actually has the opposite effect on pain! Long term use can increase the efficacy of the danger pathways by sending more danger signals to the brain and increasing the volume of those signals. This causes a your nervous system to become more sensitive and therefore it takes less input to the system to cause pain. In a nutshell: when you take opioids for long term pain relief or for more chronic conditions they will cease to relieve you pain and most likely make it worse!
Let's talk about the first definition above. I am sure you are thinking what is an endogenous neural polypeptides? It is a neurotransmitter that already exists in your own body! Believe it or not your own brain has more pain fighting capabilities than you can ever take from a pill. Is that great news or what! The question is how do we harness those neurotransmitters to work for us? Check out this quick video from Dr. David Butler to find out how. Hint...it has to do with the brain!
** The opioid epidemic in the United States has reached a crisis level. For more information about the opioid epidemic check out the resources from the U.S. Department of Health and Human Services.
#6 fear Avoidance can Make Pain Worse
Have you ever said to yourself "I can't do that movement, it will make my pain worse" or "I would love to go out with my friends but I am afraid it will make my pain worse" or "I can't do that activity, it will make my pain worse"? These are all examples of fear avoidance thoughts that, more often than not, become fear avoidance behaviors. These behaviors can lead to disuse of the musculoskeletal system, social isolation, hypervigilance to your pain condition and continue the thinking of "I have pain therefore I am damaged". Studies have shown that fear avoidance behavior can actually make your pain worse and chronic. So, make sure that you keep yourself moving by going for a walk or performing exercises given to you from your physical therapist. You want to make an effort to be with friends and family and continue to have a social life. Remember that being active physically, mentally and socially will have positive input to your brain and it may be enough to break up that danger signal and turn down your harm alarm.
#7 Your pain is Real!
One last thing to remember...your pain is real pain! Having lived through years of chronic neck pain myself I cannot stress this last point enough. This is especially important for those with chronic pain conditions. On the outside you look just fine. You are not necessarily walking with an assistive device, you don't always have a brace on, you are still going to work, you are taking care of your family and you are trying to spend time out on the town. Because of this people may not understand or they may even question that you are LIVING with chronic pain. There is no doubt this can be upsetting and frustrating at times. Know that if you are feeling pain it is real and you are not making it up and it is not all in your head!
I hope that these 7 surprising facts about pain give you a better understanding of this complex human epidemic. Pain is never simple and in chronic conditions you need a team on your side. That team may include a physician, a pain psychologist, a health or life coach, supportive family and friends and of course your PHYSICAL THERAPIST!
I am here to answer YOUR questions about pain. Like I said, you or your loved one need a team on your side. As someone who has lived with persistent pain, I understand how frustrating it can be to find the help you need. Let's talk.