Pain education has many health benefits. Research shows that understanding what pain is and how it works changes the way you think about pain, improves your mobility, and even reduces your pain. These benefits are greater when education is combined with other strategies for managing pain.
There is no cure for chronic pain. The goal of chronic pain treatment is learning how to manage your pain. Surgery and medication may be helpful for some people, but practicing healthy habits such as improving sleep and reducing stress are also very important. Learning how to manage your pain can begin with education but finding the right strategy that works for you is an ongoing journey.
Pain is complex but research shows that anyone can understand the science of pain. To help your learning, we use metaphors to explain pain and describe what is happening in the human body.
- Pain is normal and an important part of the body’s warning system.
- The brain receives many signals before deciding if something is painful.
- Pain is more than the state of the tissues. We feel pain when the brain decides that there is a threat to the body.
- In persistent (or chronic) pain, the nervous system is overexcited (or sensitized). It takes very little stimulation for the brain to create a pain experience. .
- Your thoughts, emotions, and activity can increase the sensitivity of the nervous system. This can mean that you feel pain more often and more intensely.
- Stress makes the pain experience worse.
Pain is normal and an important part of the body’s warning system. Pain is an unpleasant physical and emotional feeling from actual or potential tissue damage. Many of you would agree pain is a nuisance, undesirable, and something to avoid. What you may forget are the benefits of having pain. Pain has a purpose – to warn you of injury. By being unpleasant, pain makes you think differently, behave differently, and move differently. It makes you react in ways that protect you when you are hurt or before you are hurt badly. Pain is unpleasant but it is a normal human experience and your body’s way to warn you of danger.
The human body as a house and pain as a smoke alarm. If the alarm goes off, your natural reaction is to look for fire in the house. If the fire is small or there is little smoke, you may try to fight the fire. If the fire is big or there is lots of smoke, you will likely call for help. Like a smoke alarm, pain warns you of danger and makes you take action.
What is happening in the body?
Scattered all over the body are millions of nociceptors (“danger” sensors) that are constantly surveying its environment. These sensors are everywhere – in the nerves inside your skin, muscles, bones, and even your brain. Sensors can be specialized. Some react to temperature (feeling hot or cold), and others to stress chemicals (feeling anxious), immune chemicals (when you are sick), mechanical forces (pinching or pressure), or the slowing down of blood flow around your tissues. Nociceptors send signals that travel along the nerve fibers, up the spinal cord, and to the brain. The brain processes this information and sends messages back down the spinal cord and along the nerve fibers to tell the body what to do (or not do).
Suppose you step on glass, nociceptors in your foot detect the injury and send “danger” signals to your brain. Your brain turns the pain alarm on and you feel pain. Pain protects you because the brain also sends messages to the body that make you pay attention to the injury, sit down and put less pressure on the foot, and remove the piece of glass that is causing harm.
Understanding nociceptors, nerve fibers, spinal cord, and brain are important but we now know that the pain experience is not this simple. Other activities such as inflammation (the body’s normal response to injuries or infections) and neuropathy (nerve damage) also send alarm signals to the brain.
- Metaphor: pain is a smoke alarm in your body that warns you of danger (fire).
- Nociceptors are “danger sensors” that detect activity in the body. They do not detect pain.
- Nociceptors send alarm or “danger” signals from the body to the brain. This signal is NOT pain yet.
- Pain is an experience made in the brain to protect you from danger.
- The brain has many areas that work together to get you out of danger.
Pain does not happen just because the brain receives “danger” signals. Danger signals are one of many signals from the body to the brain. Before the pain alarm turns on, the brain must put together a reasonable story from all the information it receives.
What is happening in the body?
Alarm signals do not travel from sensors to the brain in a straight line. These signals must first pass through a “nerve gate” in an area called the dorsal horn in the spinal cord. You are more likely to feel pain when the gate opens because alarm signals are free to travel to the brain. You are less likely to feel pain when the gate closes because alarm signals cannot travel to the brain. The brain opens and closes the nerve gate by sending signals down the spinal cord.
Stress, fear and worried thoughts are some signals that keep the gate open and increase your pain. Signs of safety in the body like calm thoughts, deep breathing or gentle movement can lower your pain by closing the gate.
Now suppose you step on glass, but this time, you are on a stage to receive a very important award. The piece of glass may cause little or no pain. This is not because danger signals are not travelling from your foot to your brain. It is because feeling very excited can stimulate nerve fibers and feel good chemicals that close the nerve gate. Closing the nerve gate slows down danger signals to the brain. Fewer alarm signals means the brain is less aware of dangers and less likely to protect you with pain. After your feeling of excitement comes down, you may start noticing a pain in your foot.
- Metaphor: brain is your body’s CEO who looks at a whole situation before protecting by pain and sending signals to close or open the gates.
In the body:
- Alarm or “danger” signals go through a nerve gate before going to the brain.
- When the gate opens, alarm signals travel freely from the body to the brain and you are more likely to feel pain.
- When the gate closes, alarm signals stop or slow down from the body to the brain and you are less likely to feel pain.
- Pain reducing signals (e.g. signs of safety in the body like calm thoughts, deep breathing, soothing heat or ice, medication) send messages down the spinal cord that close the gate.
- Pain intensifying signals (e.g. stress, discouraging thoughts, fear of injury, signs of potential danger) send messages down the spinal cord that keep the gate open.
Purpose of Pain
Pain is more than the state of the tissues. You feel pain when the brain decides that there is a threat to the body.
There is a tendency to think more pain means more damage and less pain means less damage. Animal and human studies show that tissue damage does not predict pain. Major injuries send louder danger signals but danger signals are not pain. Pain happens when the brain interprets these signals and decides that there is a threat to the body.
That the CEO (your brain) receives a report about an issue from one department. The CEO looks at all the information and asks, “Is there a threat to the company?” If the answer is yes, the CEO sends an urgent message (protection through pain) to fix the issue. If the answer is no, the CEO reassures its employees instead (does not need to protect with pain). Deciding if an issue is a threat or not depends on how the CEO interprets the situation. Like a CEO, the brain sends a pain message when it thinks the body is in danger.
What is happening in the body?
It is possible to feel pain when there is no tissue damage. Or to feel no pain when there is tissue damage. Pain is more about what the brain thinks is dangerous than it is about tissue damage. Knowing the context or meaning of your pain is important to understand why you have pain.
Suppose you step on glass, but this time, you are in the middle of a road and a bus is heading toward you. At this time, you may not feel pain in your foot. Why? Because your brain puts together all the information it has (what you see, what you hear, what you know about buses) and decides that the risk of being run over is more dangerous than damage from glass in your foot. The pain alarm does not turn on at this time. When you are safe from the bus, you may start to feel pain in your foot. This is because the brain looks at the information it has now and decides that the piece of glass in your foot is a danger that needs attention.
- Metaphor: brain (your body’s CEO) turns on the pain alarm only when it thinks your body (company) is in danger.
In the body:
- Context is important to understand why we have pain.
- Pain is a message the brain sends to the body when it decides you are in danger and need to take action.
- The brain quickly and unconsciously decides how dangerous a situation is.
- The danger can be real or believed, but it is always being compared to other situations the person is facing.
Acute Pain Versus Chronic Pain
The pain experience described so far is what happens in acute pain. Acute pain is short lasting (up to 3 months) and is your body’s normal response to tissue damage (sprains, surgery). When pain lasts longer than 3 months, it becomes persistent (or chronic).
Unlike acute pain, chronic pain is long lasting (more than 3 months). Chronic pain may begin after an injury but tissue injury is not the cause of ongoing pain. This is because tissue healing from injury is usually complete by 3 months. Chronic pain is less about tissue damage and more about having an highly sensitive pain alarm system.
The human body as a house and chronic pain as a smoke alarm that keeps going off. When the alarm turns on, your natural reaction is to look for a fire. If you search the house and do not find a fire time after time, you need to check the alarm itself. Maybe the settings are too sensitive and it picks up other activities in the house (e.g. footsteps). Like a smoke alarm that goes off with no fire, chronic pain is more about having a highly sensitive nervous system sending pain signals to the body than tissue damage.
What is happening in the body?
Neuroplasticity is the ability of the brain to change over time. The pattern of connections between brain areas can become like a well worn path. Brain connections are like paths through fresh snow. When you use the same parts of your brain together, and they send messages back and forth the same way over and over, it is like creating a faster path. When you are starting a new strategy or doing something new to manage your pain, it will be like making a new path through the snow.
Neuroplasticity happens throughout your whole life, not just as children/teens. Anytime you learn or experience, or remember anything, you are changing the connections in your brain. Sometimes this is referred to as “what fires together, wires together” – the parts of the brain working together communicate more quickly over time.
It takes time to make new paths. Like walking through deep snow, it isn’t easy! Even when you lay down a new path, sometimes it “snows” and you need to go over it again. But, over time, you can make new connections and go down those pathways more easily and quickly. When a path is already there, when a brain area has already been connected to another area in a new way, then it becomes easier to use that pathway.
For example, if every time you have a burning or aching sensation, your thought is “ow! This is awful. I hate being in pain”, then that thought is connected strongly in your brain to the aching sensation. It is easy for your brain to follow that pathway. But if you start thinking a new thought, like, “this aching is uncomfortable but it isn’t dangerous” then over time that may become a more automatic thought pathway.
- Metaphor: chronic pain is a smoke alarm in your body with sensitive settings.
In the body:
- Chronic pain is less about tissue damage and more about having a sensitized nervous system.
- Different activities easily turn on the pain alarm system.
- Chronic pain not a sign that the body is in danger.
Factors That Affect Pain
The nervous system is more sensitive in some people and less sensitive in others. Chronic pain may be more common after a major injury. Genetics may be another reason. Unfortunately, you have little control over these things.
What you do have control over is how your mood, behaviour, and activity affects your pain. Learning how these factors influence pain will help you understand what makes your pain worse and what makes it better.
The human body as a house and chronic pain as a smoke alarm that goes off when there is no fire. You notice that using the oven without turning the kitchen fan on makes the alarm go off. The alarm also goes off when the house is warmer than 23⁰C. Noticing what turns the alarm on can help you avoid unnecessary alarms. You can quiet the alarm by turning on the fan when using the oven and cooling the house below 23⁰C. Like a smoke alarm that easily reacts, knowing how your mood, behaviours, and activity levels affects pain can help you find healthy living strategies to reduce your pain.
What is happening in the body?
Psychological, behavioural, and activity factors such as stress, fatigue, low mood, inactivity or over activity, sleeping difficulties, and smoking make your nervous system more sensitive. They increase the baseline electrical activity in the nerves. This means it takes less stimulation for the nerve to reach the “alarm threshold” and for danger signals to travel to the brain.
- Metaphor: chronic pain is a smoke alarm in your body with sensitive settings. Knowing what turns the alarm on can help you find ways to quiet down the alarm.
In the body:
- Psychological, behaviour, and activity factors increase the electrical activity in your nerves and make your nervous system even more sensitive.
- In chronic pain, the brain receives more danger messages because little stimulation can raise the electrical activity in the nerves to alarm levels.
Stress and Pain
Living with chronic pain is stressful. It actually increases stress hormones in the body. In the short term, stress hormones protect you from immediate danger by changing your body’s priorities. They increase your heart rate so blood and oxygen moves quickly in the body. They slow down your digestion so energy is available for important organs (brain, heart). They keep you awake, alert, and on guard against danger. In the long term, high levels of stress hormones can have a negative effect on your pain experience.
What is happening in the body?
Muscles and nerves become sensitive and sore
Blood flow to muscles and nerves slows down so they become more tender.
Mood swings are common
Stress chemicals affect an area in the brain that regulates emotions.
Stress chemicals affect an area in the brain that regulates appetite.
Fatigue is common
Stress hormones make you burn calories fast so you feel tired easily.
Weight gain is common
Stress hormones make you more hungry.
Stress makes it hard for deep restorative sleep.
Blood flow to big muscles (legs and arms) becomes a priority and smaller muscles that help you with posture are less important. They receive less blood supply and oxygen.
Stomach is more sensitive
Blood flow to your digestive system slows down and this makes it irritable.
Low sexual drive
Sexual activity and intimate thoughts become low priority. Stress affects your sex hormones (testosterone and estrogen) over time.
Trouble with focus and concentration
Stress hormones disrupt the production of chemicals that regulate your cognitive function.
Stress hormones disrupt the production of mood regulating chemicals (serotonin) in the body.
Managing Chronic Pain
How do you manage chronic pain? The first step is to understand what is happening in your body. Knowing what is going on can make you feel less afraid and less pain. This makes sense because your brain protects you from what it thinks is dangerous. Once your brain understands you are not in danger the pain experience decreases.
But what if pain persists? In chronic pain, the nervous system is changed and becomes overexcited by things that usually cause pain and things that do not usually cause pain. There are many ways to make your nervous system less excited. Some require help from medical professionals and some do not.
If you have been living with pain for a long time, it will take time to turn down your alarm’s sensitivity. Be patient. Your pain can improve little by little over time.
Strategies to manage chronic pain include:
Physical Activity and Exercise
- Moving can hurt but physical activity and exercise gets your heart pumping, sends blood and oxygen to your body, and increases pain killer chemicals. These are important to lower your pain.
- Physical activity is any activity that uses energy and muscles to move your body. Exercise is a type of physical activity that aims to improve your fitness level.
- Exercise can break the pain cycle, train the brain, and decrease pain over time
- Other strategies that can help you get closer to the goal of moving more are:
- Manual Therapy (need health care provider)
- TENS (possible to have your own)
- Acupuncture (need a health care provider)
- Massage (need health care provider)
Try to identify the things that increase stress in your life and decide if they are:
- Under your control- Make an action plan
- Not under your control – Let it go. This is harder than it sounds and you may need help to learn how to do this.
- Need help to manage – access help
- Strategies to reduce stress may include:
- Muscle relaxation exercise
- Deep breathing exercise
- Physical activity
- Mood and pain are closely connected but the relationship is different for each person.
- Think back to a time when you had pain. Do you think your mood affected your pain level?
- If you have not noticed a relationship, quietly observe any relationships between your pain and mood over the next few days.
Small studies show that if you are too wound up before going to sleep it will make your pain worse. TIPS for restful sleep:
- No screen time 1 hour before bed
- Limit caffeine in the afternoon or evening
- Exercise regularly
- Have a bedtime routine to wind down (bath, comfy clothes)
- Limit water or alcohol before bed
- Limit day time napping
- No kids or animals in bed
- Go to bed around the same time each day
- Studies show that pain is higher in smokers than non-smokers. Stopping smoking is also an important way to improving your pain.
When using medicines to manage pain, the 5 “S” Medication Principles should be used.
- Striking a balance between benefits and risks: The benefits (pain relief) should always be weighed against the risks (side effects) of using medicines.
- Significant pain relief: Medicine is helpful if it reduces pain by 30% or more.
- Safe use of opioid medications: Pharmacists can give you tips on safe opioid use.
- Self-Medications and prescription medications: Have a current list of the medicines you are taking and understand who, what, when, how, and why you are taking them.
- Safe storage and disposal of medications. Medicines should be stored in a safe place (locked cabinet) away from kids and pets. They should be kept away from heat, cold, and moisture. Always leave medicines in original labelled containers. Do not mix medicines in same container.
TIPS to minimize harm from medication use:
- Avoid long-term (more than 1 month) use of medicines like:
- benzodiazepines nonsteroidal anti-inflammatory drugs
- Talk to your health care provider about "de-prescribing” (reducing or stopping medicines that are no longer helping).
- Take medicines according to their recommended dose. Increasing doses of some medicines does not always have more benefits for pain.
Surgical Interventions (require medical personnel)
Surgical interventions are invasive procedures that reduce chronic pain in some people with some conditions. Some examples are:
- Epidural steroids: Injecting steroids into the spine to reduce inflammation around the nerves in the spine.
- Nerve Blocks: Injecting medicines to “numb” or freeze the nerves.
- Radio frequency ablations: Using radio waves to stop some nerves from sending danger signals to the brain.
- Neuromodulation stimulation: Inserting tubes into the body to deliver electricity to the nerves along the spine to block pain signals from the brain.
There is no guarantee that these procedures will work. These procedures are “successful” if a 30% or more decrease in pain is achieved.
Conclusion and Resources
Pain Management Essentials
- Education is critical for you to improve function and live better with your pain.
- A key is to understand why your hurts won’t harm you and that your nervous system now uses pain to protect at all costs, not to inform you about damage.
- Be patient and persistent. You can use smart activities to gradually increase your activities and involvement in life.
- Why Things Hurt by Lorimer Moseley
- Changing your pain pathways by Bonnie Cai-Duarte, Cara Kircher, Bronwen Moore, Sarah Sheffe 2018 Toronto
- Explain Pain by David Butler and Lorimer Moseley 2003 Noigroup Publications: Australia
- A Patient Book about the Neuroscience of Pain Adriann Louw 2013 International Spine and Pain Institute (USA)
Explaining Chronic Pain to Persons Living with Chronic Pain
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- Facet Joint Injection https://www.spine-health.com/video/facet-joint-injections-procedure-video
- Anti-Inflammatory Medications for back pain https://www.spine-health.com/video/anti-inflammatory-medications-back-pain-relief-video
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