|Posted on March 5, 2020 at 9:00 AM|
Central Sensitization: A Generator of Pain Hypersensitivity by Central Neural Plasticity
Alban Latremoliere and Clifford J. Woolf
Neural Plasticity Research Group, Department of Anesthesia and Critical Care, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts
Central sensitization represents an enhancement in the function of neurons and circuits in nociceptive pathways caused by increases in membrane excitability and synaptic efficacy as well as to reduced inhibition and is a manifestation of the remarkable plasticity of the somatosensory nervous system in response to activity, inflammation, and neural injury. The net effect of central sensitization is to recruit previously subthreshold synaptic inputs to nociceptive neurons, generating an increased or augmented action potential output: a state of facilitation, potentiation, augmentation, or amplification. Central sensitization is responsible for many of the temporal, spatial, and threshold changes in pain sensibility in acute and chronic clinical pain settings and exemplifies the fundamental contribution of the central nervous system to the generation of pain hypersensitivity. Because central sensitization results from changes in the properties of neurons in the central nervous system, the pain is no longer coupled, as acute nociceptive pain is, to the presence, intensity, or duration of noxious peripheral stimuli. Instead, central sensitization produces pain hypersensitivity by changing the sensory response elicited by normal inputs, including those that usually evoke innocuous sensations.
Perspective—In this article, we review the major triggers that initiate and maintain central sensitization in healthy individuals in response to nociceptor input and in patients with inflammatory and neuropathic pain, emphasizing the fundamental contribution and multiple mechanisms of synaptic plasticity caused by changes in the density, nature, and properties of ionotropic and metabotropic glutamate receptors.
|Posted on January 23, 2020 at 1:05 PM|
Somewhere at around the mile 8 marker of my 20 mile run a few weeks ago, I felt a familiar (and terrifying) sensation: My leg was beginning to cramp up and I wasn’t even halfway through my run. Having experienced this just one time before—and it ruined a marathon for me—I decided to use it as an opportunity to work on my problem-solving skills. I calmed down, increased my salt intake and used mental mantras to get myself through the run. And as soon as the run was over, I called my doctor of physical therapy (DPT) and scheduled an appointment for the next week.
I found my DPT late last fall after a painful marathon (involving that first cramping experience) that I followed up with another marathon in hopes to erase the pain of the previous one. I then ‘ran’ a race on an icy path and after that, I knew I needed to see a professional about my out-of-whack body. It was probably one of the best decisions I made. I learned that like many runners, my hips and glutes were weak, causing all sorts of problems.
Over the next few months, we worked through my problems and I got stronger and faster. My visits moved from twice a week to once a week, then to once a month and finally to maintenance visits every six weeks or so. When I was ‘cleared’ by my DPT, I decided to keep a standing appointment every two months just to keep myself honest regarding my drills and form. Having a professional to call when things don’t go as planned has been invaluable.
After my painful 20-miler, I went into my DPT’s office and told her what happened. She began massaging my tight calf and said, “Yep—glad you came in because this could’ve absolutely blown up into something awful.” As we moved from the massage to dry needling (not the most comfortable thing in the world, but tolerable), I just thought about how glad I was that I had someone I could call when things like a terrible calf cramp happened. A year ago, I would’ve just tried to continue to run through it and probably would’ve ended up doing something to make it worse.
Physical therapy is not free, so I know it’s a luxury for me to be able to go every two months or so, but it’s worth the cost to be able to stay running healthily. Even if you just go once to get evaluated, I would recommend not ignoring those little (or not so little) pains that just won’t go away. Let a professional help you fix it and become a stronger runner. I know I’m so grateful that I did.
Do you have a DPT you can call if you feel injured?
|Posted on November 13, 2019 at 10:50 AM|
Please Watch this wonderful video explaining why we cant trust dermatomes as the only way for pain mapping.
|Posted on November 7, 2019 at 11:20 AM|
What Is The Cause of Chronic Pain?
To answer this question, we need to understand some facts about the nervous system.
Whatever its initial cause, pain is a function of the nervous system. Say you injure your low back. Nerves around the site of the injury detect it and sends signals that travel on a highway of nerves from the injury to the spinal cord and up to the brain. Once they get to the brain, the brain processes the signals and they register as pain in the low back. The whole highway, from the nerves in the low back to the brain, is the nervous system.
At the same time as the signals travel from the injury to the brain, the whole nervous system becomes reactive. Like a fire detector in a building sounding the alarm in response to fire, the nervous system sets off the alarm bells when in pain. Our muscles become tense forming trigger points. We guard and grimace. We cry and are emotionally alarmed. The nervous system controls all these reactions. We can think of it as the whole nervous system going into ‘red alert.’
This reactivity of the nervous system is all well and good when it comes to acute pain. It helps us to know that something is wrong. Becoming alarmed, we protect against further injury and seek help. Once the original injury or illness heals, everything about the nervous system comes back to normal.
In some people, the nervous system can stay in a persistent state of reactivity even upon healing of the original acute injury or illness. The whole nervous system becomes more and more reactive in a process called wind-up. This reactivity of the nervous system comes to maintain pain in a vicious cycle, over and above the pain of the original condition that started it all. The end state of this process is a highly reactive nervous system called central sensitization.
What is that???
The hallmarks of central sensitization are increasingly widespread pain and increasingly intense pain. Suppose you have an injury to your neck and come to have chronic neck pain. Once central sensitization sets in, you also develop pain in your shoulders and upper back as well as tension headaches. Additionally, the pain becomes so intense that even touch can hurt.
Other problems occur as well with central sensitization. Since the nervous system also controls our emotional lives, a highly reactive nervous system leads to anxiety and irritability, poor sleep, fatigue, and eventually depression. These psychological problems are secondarily stressful. The stress adds to the reactivity of the nervous system, making the pain worse. Another vicious cycle results.
The upshot of it all is that chronic pain is pain causing pain by way of central sensitization.
Central sensitization is a condition of the nervous system that is associated with the development and maintenance of chronic pain. When central sensitization occurs, the nervous system goes through a process called wind-up and gets regulated in a persistent state of high reactivity. This persistent, or regulated, state of reactivity lowers the threshold for what causes pain and subsequently comes to maintain pain even after the initial injury might have healed.
Central sensitization has two main characteristics. Both involve a heightened sensitivity to pain and the sensation of touch. They are called allodynia and hyperalgesia.
Allodynia occurs when a person experiences pain with things that are normally not painful. For example, chronic pain patients often experience pain even with things as simple as touch or massage. In such cases, nerves in the area that was touched sends signals through the nervous system to the brain. Because the nervous system is in a persistent state of heightened reactivity, the brain doesn't produce a mild sensation of touch as it should, given that the stimulus that initiated it was a simple touch or massage. Rather, the brain produces a sensation of pain and discomfort.
Hyperalgesia occurs when a stimulus that is typically painful is perceived as more painful than it should. An example might be when a simple bump, which ordinarily might be mildly painful, sends the chronic pain patient through the roof with pain. Again, when the nervous system is in a persistent state of high reactivity, it produces pain that is amplified.
Chronic pain patients can sometimes think they must be going crazy because they know intellectually that touch or simple bumps shouldn’t be as uncomfortable or painful as they experience them. Other times, it’s not the patients themselves who think they are crazy, but their friends and loved ones. Friends and loved ones can witness the chronic pain patient grimacing at the slightest touch or crying out at the simplest bump and they think that the chronic pain patient must really be a hypochondriac or something. After all, the contrast between them and the chronic pain patient is stark: the friends and loved ones can be touched or get a bump and it doesn’t send them through the roof. The difference, though, is that the friends and loved ones don’t have a nervous system that is stuck in a persistent state of heightened reactivity, called central sensitization.
|Posted on June 29, 2019 at 9:30 PM|
Upper trapezius and its referral sources
The trapezius commonly contains trigger points, and referred pain from these trigger points bring patients to the office more often than for any other problem. As you can see from the picture, the trapezius is a large kite-shaped muscle, covering much of the back and posterior neck.
There are three main parts to the muscle: the Upper, middle, and lower trapezius, and each part has its own actions and common symptoms.
headaches on the temples / "tension" headaches
facial, temple, or jaw pain
pain behind the eye
dizziness or vertigo (in conjunction with the sternocleidomastoid muscle)
severe neck pain
a stiff neck
intolerance to weight on your shoulders
headaches at the base of your skull
TrP5 refers superficial burning pain close to the spine
TrP6 refers aching pain to the top of the shoulder near the joint
mid-back, neck, and/or upper shoulder region pain
possibly referral on the back of the shoulder blade, down the inside of the arm, and into the ring and little fingers (TrP7), very similar to a serratus posterior superior referral pattern
headaches at the base of the skull
Sime points can refer a deep ache and diffuse tenderness over the top of the shoulder
Causes and Perpetuation of Trigger Points
one leg shorter than the other
a hemipelvis that is smaller on one side (the part of the pelvis you sit on)
short upper arms (which causes you to lean to one side to use the armrests)
tensing your shoulders
cradling a phone between your ear and shoulder
a chair without armrests, or the armrests are too high
typing with a keyboard too high
sewing on your lap with your arms unsupported
sleeping on your front or back with your head rotated to the side for a long period
playing a violin
sports activities with sudden one-sided movements
sitting without a firm back support (sitting slumped)
any profession or activity that requires you to bend over for extended periods (i.e.. dentists/hygienists, architects/draftsmen, and secretaries/computer users)
bra straps that are too tight (either the shoulder straps or the torso strap)
a purse or daypack that is too heavy
a mis-fitting, heavy coat
carrying a day pack or purse over one shoulder -- even if you think you are not hiking up one shoulder, you are, no matter how light the item
whiplash (a car accident, falling on your head, or any sudden jerk of the head) 10
walking with a cane that is too long
turning your head to one side for long periods to have a conversation
tight pectoralis major muscles
The Trapezius is a very important shoulder girdle muscle that is often overlooked as the cause of long term chronic pain.
|Posted on May 20, 2019 at 4:25 PM|
One of the components of the cranial concept for practitioners who practice cranial manipulative therapy is that the bones of the head move along the sutures. The movement can be described as an expansion and compression that take place much how the rib cage moves during respiration. This idea has been highly controversial since it was first presented to the world over 60 years ago. To this day, there’s plenty of criticism that this concept is based on ‘pseudoscience.’ Many state that there is ‘no research’ supporting this idea. This statement is incorrect. There may not be sufficient evidence at this time supporting this idea. However, there is much more research showing that there the bones of the head can move, than there is research showing that the bones of the head do not move.
I'd like to to discuss 5 reasons I have found that support the bones of the head do move.
Reason 1: Embryological
Why are there sutures in the head? If you look at a skull, there are sutures throughout the head making each bone identifiable. This may seem insignificant as evidence but during development, there are many bones that form in separate parts and do actually fuse to form one bone. For example, each pelvic bone develops as three separate parts (ischium, ilium, and pubis) that fuse into one bone with no sutures between them. There are many examples of this during development. This even takes place in the head. The occiput forms by the fusion of 4 separate components. This fusion is complete and does not have any sutures between them. There are sutures between the occiput and the bones it articulates with. Clearly the human body would be capable of completely fusing the bones of the head if it intended it to do so. This fusion, however, does not take place or one would be unable to distinguish each separate bone of the skull once fusion had taken place. In addition, skulls can be disarticulated using the expansive properties of rice to separate the bones at the sutures. So if the body is capable of completely fusing the bones of the head, then why does it not do this?
Reason 2: Adaptation
Although there are not large amounts of movement in the head, there is some. Proper motion allows the head to be pliable to better absorb the shock of a trauma or changes in intracranial pressure. Part of the purpose of the skull is to encase and protect the brain. If one receives a blunt trauma to the head, the pliability allowed by movement of the bones of the head allows the bones to absorb much of the impact. This would allow the brain to be less affected by the trauma. If the skull fused, then the skull would be very hard like the outer casing of a helmet. A blunt trauma would break the skull easier like an egg shell and the force would be transferred to the brain more strongly. By not fusing, the head can then change and adapt better to changes in intracranial pressure. If a scenario occurs where the pressure in the head changes (such as flying or having a cold), then it would be helpful for the bones to be pliable and expand. That way, when the pressure in the head changes, the effect on the brain is minimized. Therefore, in terms of being able to handle traumas and changes in pressure, it would make sense of the head to be able to expand.
Reason 3: Braces
We have evidence that the bones of the head can move all around us. If the bones of the head fuse and could not move, there would be no reason for braces. Braces are based on the idea that the head is pliable and can be reshaped to align teeth.
Reason 4: Motion Testing
Part of the reason that there is so much controversy about whether or not the bones of the head move or not is because most practitioners put their hands on a persons head and palpate the subtle movement taking place under their hands. Others who come along who cannot palpate this motion, then argue that this cannot be felt. Although I can feel this subtle motion, I feel restrictions in the cranial bones by getting a hold of the accessible bones of the head and move them through their range of motion. I compare how one side moves compared to the other. Usually one side moves better than the other. Under normal circumstances each bone has a small range of motion. There is significantly more motion than taking a plastic skull and trying to move it. By understanding where there are restrictions in the sutures, then I can work on freeing them up until both sides feel more symmetrical in their movement. I prove this idea to myself every day that I am at work.
Reason 5: Layout of Sutures
Finally the last piece of evidence I have found is in the sutures themselves. This goes back to anatomy. If one studies the way the motion described in the skull and the anatomy of the sutures, then one could see this idea as being plausible. There are different types of sutures and they articulate differently depending on the area. For example, the frontal bone overlaps the parietal bone medially, but as one moves out further along the coronal suture, there is a transition spot followed by the parietal bone overlapping the frontal bone. The sagittal suture for example, acts more like a hinge and the suture is put together in a way that allows for this type of a function. These are just a few examples although this takes place with the way all the bones articulate with each other. Simply put, the bones of the head act like a 3D puzzle that allows the head to go through its motion. In addition, dural membranes in the head come out externally through the sutures. Evidence for this is that epidural bleeds in the head do not cross suture lines because the dura travels externally at the sutures. The dural membranes inside the head act as a barrier preventing the bones of the head from fusing completely.
We also know now that there are structures inside the skull that we are affecting with cranial manipulative techniques. The tentorium, cranial arterials, CSF, also transmit pain information to our brain. This can be attenuated with cranial technique.
I will post a video of the skull bones moving in real time!
|Posted on May 18, 2019 at 10:15 PM|
Your daily cup of coffee may be doing more for you than providing that early-morning pick-me-up. The health impact of coffee has long been a controversial topic, with advocates touting its antioxidant activity and brain-boosting ability, and detractors detailing downsides such as insomnia, indigestion and an increased heart rate and blood pressure. But the latest wave of scientific evidence brings a wealth of good news for coffee lovers. Here are 10 reasons drinking coffee may be healthier for you than you thought.
1. Coffee is a potent source of healthful antioxidants.
In fact, coffee shows more antioxidant activity than green tea and cocoa, two antioxidant superstars. Scientists have identified approximately 1,000 antioxidants in unprocessed coffee beans, and hundreds more develop during the roasting process. Numerous studies have cited coffee as a major — and in some cases, the primary — dietary source of antioxidants for its subjects.
How it works: Antioxidants fight inflammation, an underlying cause of many chronic conditions, including arthritis, atherosclerosis and many types of cancer. They also neutralize free radicals, which occur naturally as a part of everyday metabolic functions, but which can cause oxidative stress that leads to chronic disease. In other words, antioxidants help keep us healthy at the micro-level by protecting our cells from damage. Finally, chlorogenic acid, an important antioxidant found almost exclusively in coffee, is also thought to help prevent cardiovascular disease.
2. Caffeine provides a short-term memory boost.
When a group of volunteers received a dose of 100 milligrams (mg) of caffeine, about as much contained in a single cup of coffee, Austrian researchers found a surge in the volunteers’ brain activity, measured by functional magnetic resonance imagery (fMRI), as they performed a memory task. The researchers noted that the memory skills and reaction times of the caffeinated volunteers were also improved when compared to the control group who received a placebo and showed no increase in brain activity.
How it works: Caffeine appears to affect the particular areas of the brain responsible for memory and concentration, providing a boost to short-term memory, although it’s not clear how long the effect lasts or how it may vary from person to person.
3. Coffee may help protect against cognitive decline.
In addition to providing a temporary boost in brain activity and memory, regular coffee consumption may help prevent cognitive decline associated with Alzheimer’s disease and other types of dementia. In one promising Finnish study, researchers found that drinking three to five cups of coffee daily at midlife was associated with a 65 percent decreased risk of Alzheimer’s and dementia in later life. Interestingly, the study authors also measured the effect of tea drinking on cognitive decline, but found no association.
How it works: There are several theories about how coffee may help prevent or protect against cognitive decline. One working theory: caffeine prevents the buildup of beta-amyloid plaque that may contribute to the onset and progression of Alzheimer’s. Researchers also theorize that because coffee drinking may be associated with a decreased risk of type 2 diabetes, a risk factor for dementia, it also lowers the risk for developing dementia.
4. Coffee is healthy for your heart.
A landmark Dutch study, which analyzed data from more than 37,000 people over a period of 13 years, found that moderate coffee drinkers (who consumed between two to four cups daily) had a 20 percent lower risk of heart disease as compared to heavy or light coffee drinkers, and nondrinkers.
How it works: There is some evidence that coffee may support heart health by protecting against arterial damage caused by inflammation.
5. Coffee may help curb certain cancers.
Men who drink coffee may be at a lower risk of developing aggressive prostate cancer. In addition, new research from the Harvard School of Public Health suggests that drinking four or more cups of coffee daily decreased the risk of endometrial cancer in women by 25 percent as compared to women who drank less than one cup a day. Researchers have also found ties between regular coffee drinking and lower rates of liver, colon, breast, and rectal cancers.
How it works: Polyphenols, antioxidant phytochemicals found in coffee, have demonstrated anticarcinogenic properties in several studies and are thought to help reduce the inflammation that could be responsible for some tumors.
6. Coffee may lessen your risk of developing type 2 diabetes.
A growing body of research suggests an association between coffee drinking and a reduced risk of diabetes. A 2009 study found that the risk of developing diabetes dropped by 7 percent for each daily cup of coffee. Previous epidemiological studies reported that heavy coffee drinkers (those who regularly drink four or more cups daily) had a 50 percent lower risk of developing diabetes than light drinkers or nondrinkers.
How it works: Scientists believe that coffee may be beneficial in keeping diabetes at bay in several ways: (1) by helping the body use insulin and protecting insulin-producing cells, enabling effective regulation of blood sugar; (2) preventing tissue damage; and (3) and battling inflammation, a known risk factor for type 2 diabetes. One component of coffee known as caffeic acid has been found to be particularly significant in reducing the toxic accumulation of abnormal protein deposits (amyloid fibrils) found in people with type 2 diabetes. Decaffeinated coffee is thought to be as beneficial, or more so, than regular.
Note: There is some evidence that coffee decreases the sensitivity of muscle cells to the effects of insulin, which might impair the metabolism of sugar and raise blood sugar levels. The significance of this finding, however, is still unclear.
7. Your liver loves coffee.
It’s true: In addition to lowering the risk of liver cancer, coffee consumption has been linked to a lower incidence of cirrhosis, especially alcoholic cirrhosis. A study in the Archives of Internal Medicine demonstrated an inverse correlation between increased coffee consumption and a decreased risk of cirrhosis — a 20-percent reduction for each cup consumed (up to four cups).
How it works: Scientists found an inverse relationship between coffee drinking and blood levels of liver enzymes. Elevated levels of liver enzymes typically reflect inflammation and damage to the liver. The more coffee subjects drank, the lower their levels of enzymes.
8. Coffee can enhance exercise performance.
We’ve been conditioned to believe that caffeine is dehydrating, one of the primary reasons why fitness experts recommend nixing coffee pre- and post-workout. However, recent research suggests that moderate caffeine consumption — up to about 500 mg, or about five cups per day — doesn’t dehydrate exercisers enough to interfere with their workout. In addition, coffee helps battle fatigue, enabling you to exercise longer.
How it works: Caffeine is a performance and endurance enhancer; not only does it fight fatigue, but it also strengthens muscle contraction, reduces the exerciser’s perception of pain, and increases fatty acids in the blood, which supports endurance.
9. Coffee curbs depression.
Multiple studies have linked coffee drinking to lower rates of depression in both men and women. In several studies, the data suggested an inverse relationship between coffee consumption and depression: in other words, heavy coffee drinkers seemed to have the lowest risk (up to 20 percent) of depression.
How it works: Researchers aren’t yet sure how coffee seems to stave off depression, but it is known that caffeine activates neurotransmitters that control mood, including dopamine and serotonin.
10. Coffee guards against gout.
Independent studies on the coffee consumption patterns of men and women suggest that drinking coffee regularly reduces the risk of developing gout. Researchers in the Nurses’ Health Study analyzed the health habits of nearly 90,000 female nurses over a period of 26 years and found a positive correlation between long-term coffee consumption and a decreased risk for gout. The benefit was associated with both regular and decaf consumption: women who drank more than four cups of regular coffee daily had a 57 percent decreased risk of gout; gout risk decreased 22 percent in women who drank between one and three cups daily; and one cup of decaf per day was associated with a 23 percent reduced risk of gout when compared to the women who didn’t drink coffee at all. Similar findings have been documented for men: another large-scale study, published in the journal Arthritis & Rheumatism, found that men who drank four to five cups of coffee per day decreased their risk of gout by 40 percent, and that those who consumed six cups or more lowered gout risk by 60 percent.
How it works: According to the Nurses’ Health Study, coffee’s antioxidant properties may decrease the risk of gout by decreasing insulin, which in turn lowers uric acid levels (high concentrations of uric acid can cause gout).
The Cons of Coffee Drinking
The potential health benefits of drinking coffee are exciting news, but that doesn’t mean more is better. For some people, coffee can cause irritability, nervousness or anxiety in high doses, and it can also impact sleep quality and cause insomnia. In people with hypertension, coffee consumption does transiently raise their blood pressure — although for no more than several hours — but no correlation has been found between coffee drinking and long-term increases in blood pressure or the incidence of cardiovascular disease in patients with pre-existing hypertension.
Caffeine affects every person differently, so if you experience any negative side effects, consider cutting your coffee consumption accordingly. It takes about six hours for the effects of caffeine to wear off, so limit coffee drinking to early in the day, or switch to decaf, which only contains about 2 to 12 mg of caffeine per eight ounces. Always taper your coffee consumption gradually. Avoid quitting coffee cold turkey; doing so can lead to caffeine withdrawal symptoms that may include severe headache, muscle aches and fatigue which can last for days.
How to Keep It Healthy
So how much coffee is healthy, and how much is too much? Two to three eight-ounce cups per day is considered moderate; heavy coffee drinkers consume four cups or more daily. Remember, the amount of caffeine per coffee beverage varies depending upon the preparation and style of beverage. Eight ounces of brewed coffee may contain as little as 80 to as much as 200 mg of caffeine per cup (an “average” cup probably contains about 100 mg).
Your best bet: Skip the sugar-laden coffeehouse beverages and order a basic black coffee. Alternatively, switch to plain whole milk or unsweetened soy or nut milk.
|Posted on April 19, 2019 at 9:00 AM|
This morning I woke up and was greeted with many a sneeze. Most of us living in the Ohio Valley are plagued every spring and fall by seasonal allergies. Sometimes these little nuisances come and go, other times they stay and become a problem. Especially if one has chronic sinus infections and/ OR ear infections. Our dynamic skull requires air resistance to continue to function properly in our day to day lives. If something such as a sinus infection, trauma, ear infection, or other malady is present for a long period of time, our skull does not recieve the normal air resistance it needs to maintain compliance and therefore have normal function. Dysfunctions of the cranial bones can present in many ways, too many to list here, but if someone has had chronic sinusitis they may benefit from cranial manual therapy. Cranial manual therapy are gentle techniques that encourage our skull to become compliant with its dynamics again which allow for normal function of the cranial bones. What this means for a person suffering from chornic sinus infections, is less pain, less clogged sinus cavities and less headaches. Cheers to Spring!
|Posted on February 3, 2019 at 2:10 PM|
Yep, you read that right. Can you have a sore throat that is caused by your SHOULDER? Well, we arent talking about a sore throat in the classical sense but a muscle that runs from your neck to your shoulder. Yep, there is one! This muscle can have referral to the anterior throat when the restriction/trigger point is at the insertion of the shoulder. Yep, that muscle is called OMOHYOID. Heres a picture below:
|Posted on January 4, 2019 at 10:00 AM|
Have you ever wanted a quick way to see if you may be at risk or more likley to develop TMJ pain and or facial pain?
There is a simple way to check you own facial lines. All you need is a mirror!
Take a lookat your self in a relaxed position in a mirror. Where do your eyes sit? Do they sit level with one another? Or is one slight lower or higher than the other? Where do the corners of your eyes sit? Upward or downward.
Now, Look at your ears. Sepcially ear lobes. If you have detached lobes this is a bit easier to do but will still work for those who has lobes attaches to their head. Does one of your ears appear slightly lower of higher than the other? Take note of this.
Lasty look at your mouth. Where are the corners lying? is one lower than the other? are the equal? Is one lip curled up or flattened out?
If you noticed that one side you have an eye, ear and corner of the mouth that all are lower or higher OR if your eye and ears are lower but the corner of the mouth on the same side is higher, it would be an indicator that, if you are having pain, it would be from that side, or you may be likely to experience pain on that side in the future. Try it out!