This post is by Dr. Dustin Lee
Raise your hand if you have ever experienced pain before. If you are like most people, then you can probably recall at least a handful of painful experiences that you have been through. You can probably remember where you were at, what you were doing, what it felt like and who you were with when the pain occurred. Some of your experiences may have involved an unknown situation, such as bending forward and suddenly feeling back pain, while some other experiences may have been accidental, like accidentally smacking your thumb with a hammer. However, in most situations, pain was experienced for a reason, and that reason was likely to protect you from causing further harm. This is the reason you decided to stop bending forward and lifting objects, and the reason that you withdrew your thumb from holding the nail and decided to stop swinging the hammer aimlessly toward the nail.
Pain is a rather interesting topic to discuss because not many people see eye to eye on what the pain experience is. For instance, depending on your sex, culture, family environment, beliefs, experiences, etc., your perception of pain might be vastly different than someone else’s. There are Indian tribes that can pierce their bodies multiple times with hooks and hang from their piercings without displaying any signs of discomfort. If you are like me, you grimaced just from imagining or reading this; our perception of that situation is that it should be painful, but their perception must be vastly different.
I believe that we can share common ground when discussing pain. This common ground should be easily relatable to the average Jane or Joe, but also discussed at the biophysiological level when determining how we can best intervene against painful experiences with medical and healthcare providers. We will start with the definition of pain. Pain is defined by the International Association for the Study of Pain (IASP) as, “an unpleasant sensory or emotional experience in the presence of actual or potential tissue damage, or described in terms of such damage.” 1 This definition holds tremendous value because it describes pain as being a sensory experience, with the potential for having an emotional context, with or without having any type of injury (termed as trauma) associated with the body. This also implies that pain is not necessarily a simple formula where “a” equals “b,” but that the pain experience is made up of many complex interactions within our bodies that occur to produce the sensation of pain. This also implies that pain can be normal and protective when our body experiences injury or tissue trauma, but that pain can be abnormal in that it does not necessarily require injury or tissue trauma for pain to be experienced.
Seems complex? It is.
Can we do something about the pain experience? Yes.
How? By treating pain by understanding how pain is produced and where the appropriate treatment needs to be directed.
Fun to learn about? Only if you are a nerd like me.
1. Our bodies do nothave pain receptors. 4
Our bodies can take in information from our environment through touch, taste, smell, vision and hearing. These are normal senses, and we rely on them to bring context to our world. Our body has special sensors, better known as receptors, that can sense touches (including temperatures, pressures and movements), tastes, smells, sights and sounds. Under normal circumstances, this information is sent to the brain, where we store this information into useful experiences. For instance, think about your favorite food. You can imagine it perfectly, the feel of it, the taste of it, how it smells, what it looks like and potentially how it sounds. This information was retrieved from your brain because you previously experienced sensing that food, and it was important enough to call your favorite. You may have noticed at this point that I did not mention pain receptors. That is because our body has none; however, our body does have other receptors that are called nociceptors (phonetically “no-sih-cep-tors”). Nociceptors are responsible for sending warning information to the brain when there has been greater than normal sensation to the body. For instance, touching your skin is not typically painful, but pinching it firmly is: too much pressure. Holding a warm cup of coffee is not typically painful, but accidentally touching a hot stove is. Nociceptors are sensitive to high amounts of touch (including temperature, pressure, etc.), extreme temperatures of hot and cold, as well as chemical changes within the body, such as inflammation.
2. Pain is normal. 2,3
We have touched on this already; however, it should be stated clearly again that pain is typically normal and serves as a protective response. If you have just sprained your ankle, the most likely result is that you will walk with some degree of a limp. Pain is being produced as a sensation to tell you to stop putting excessive weight on the injured area to prevent further injury. There are instances where pain can be abnormal; however, and this can occur when we have pain that lasts for long periods of time with or without tissue trauma or injury. This will not be discussed in this blog.
3. Pain is 100% produced in the brain. 2,3,4
It is important to remember that too much touch, temperature, pressure, etc. is perceived by receptors called nociceptors. They are responsible for sending a warning message, through a series of connections to your brain, that says something along the lines of “something more than normal is occurring in this certain region of your body.” Remember, there is no pain still at this point. The brain then must call upon itself to give meaning to this message. Have I felt this before? When? Who was I with? Am I in a dangerous situation right now? Is there blood? This is only some of the information that the brain tries to find out as it searches your memory bank of experiences and memories. Remember, there is no pain still at the point. The brain then must determine the severity of the situation and the appropriate response. If the brain determines based on the information it was provided with and previous memories and experiences that you are in danger, then the sensation of pain is produced, and the next action is performed to get away from the dangerous situation. I suggest you take the time to watch the video herefor a funny, yet relatable, story regarding pain.
Key information: Pain is normally a sensation produced by the brain in response to warning messages from our nociceptors that are receiving information from the environment. The pain is real, even though it is being produced by the brain as a response.
What I am not saying is, “You are crazy; the pain is in your head.”
What I am saying is, “You are normal, and the pain is being produced by your brain after determining that pain needs to be present to protect yourself from further actual or potential harm.”
4. What you are told about your pain can drastically influence your pain experience. 2,3
Our brains are absolutely remarkable. We can gather information, process it and determine our next action seamlessly and quickly. We can learn new skills with countless repetitions. We can enjoy emotions and freedom of belief, make informed decision and express ourselves with language. The list continues, but it should be mentioned that every experience or new memory is associated with what you believed, thought, experienced from your senses or experienced emotionally, to name a few. These variables can drastically change how we experience a painful situation, or even how we perceive a non-painful situation to be painful. Let me provide you with tangible examples that demonstrate how this can apply.
A. You are moving heavy boxes when you suddenly feel a severe pain in your lower back. You have a hard time moving afterward, and the pain is intense. Your friends that were helping you move boxes gather around and say, “Don’t move, don’t move, don’t move; we will call the ambulance!” You have never experienced this type of pain before and are worried because you remember hearing about herniated disks, and you remember seeing this image of someone with back pain. You remember someone describing the disk to you as a jelly donut and now the “jelly” must be out of the disk, and you think this must be terrible for the back.
You get to the ER, and the doctor performs an MRI and finds that one of your disks is sticking out farther than the others. The doctor then sends you home with pain medications and tells you to follow up with physical therapy, but you are unable to get in for an appointment until a week later. You start searching online for ways to feel better, only to read countless stories of people with severe disk herniations who can no longer move their legs and have unrelenting pain. You decide that movement is too painful and that being in bed is the best case scenario.
This is a very extreme example, but it is not far off from what I may encounter at the clinic. The beliefs, thoughts, emotions, pain and behaviors that this person experienced made simple lifting pain become bed rest with fear of never walking again.
B. You are moving heavy boxes when you suddenly feel a severe pain in your lower back. You have a hard time moving afterward, and the pain is intense. Your friends that were helping you happen to be healthcare and medical providers and say, “I know you are in pain, but I want you to make sure you keep walking and moving as much as you can, as this can help to reduce some of the inflammation that may be associated with irritating a disk. You should also avoid moderate-heavy lifting and try to not sit with poor posture because this may contribute to some aggravation.” You remember the jelly donut example of the disk and become fearful that something is seriously wrong, but your friends reassure you and tell you, “The fibers that surround the middle of the disk are very strong, and there are many supporting structures the help to protect the disk material from leaving the disk. There may be very minor changes to these structures, but these will start to heal with appropriate care.” You decide that you want an MRI just to be sure. Your MRI shows you have a few disks that are sticking out more than the others, but you are then told, “Many people have these findings without any pain at all. Sometimes, you can find these changes in people that have never had back pain in the past.” You continue to move without doing the activities that aggravate your pain while waiting on your appointment with physical therapy, but once you arrive, your physical therapists reassures you that back pain resolves over time and provides you with the next step forward toward successful rehabilitation.