Trigger points causing muscle pain?
Updated: Jul 18, 2019
We have all likely heard of trigger points and maybe have a basic understanding of what they are: points in the muscle that trigger pain. We may even be able to find some of these when we “palpate” or feel our own muscles. But what exactly are they and why do they cause the muscle to be tender or painful? The purpose of this article is to dig deeper into myofascial trigger points (TrP) and provide solutions to treating them, both self-treatment and professional treatment.
Myofascial trigger points are taut bands of muscle fibers that form a continually contracted knot within the fiber (see fig. 1 above). The number of fibers involved and the size of the knot depends largely upon the degree of involvement (i.e. cause, severity, time spent in dysfunction, and ability to handle / respond to abnormal tissue function), which will be unique for each person. Once a trigger point develops, we see three things occur at the tissue level:
1. Increase in Acetylcholine at the motor endplate
a. This is the neurotransmitter that signals muscle firing. When acetylcholine is released it causes a muscle contraction. Only once this is removed from muscle cells (along with calcium) are they able to relax. An increase in acetylcholine means more muscle activity (hyperactivity) (1).
2. Increase in fiber tension
a. Hypercontracted fibers. Together multiple muscle fibers make up contractile unit, allowing a muscle to shorten and lengthen or move as a whole. When we have areas of hypercontracted fibers, these “units” no longer work as they should. The contracted unit becomes less functional compared with the other fibers (non-unison).
b. Less elasticity and greater resistance to stretching and moving (1). The TrP prefers to stay contracted and hold itself together in a knot
3. Increase in sensitizing substances within the trigger point and surrounding muscle
a. Increase in substance P, ILK-1, TNF, bradykinin (pain-sensing chemicals) (1).
b. Decrease in pH (more acidic)
c. This means the local environment becomes more conducive to pain. The nerves that sense pain (nociceptors) are fired more easily and more often, meaning more pain with less stimuli.
d. The longer we live in this environment, the more our central nervous system becomes engrained. Similar to a kid sledding down the same run every time, forming a groove or noticeable path in the snow, our nervous system acts in a similar manner. The more we use a pathway, the more recognizable and familiar it becomes, regardless if that pathway is negative (pain pathway). This leads to chronic pain patterns and a longer road to recovery.
Further, trigger points can cause what is known as "referred pain," or pain that is felt elsewhere in the body, usually at a distant spot from the actual source. For example a trigger point in the SCM muscle (neck region) can cause pain behind the ear and even in the front of the head (1).
Now that we have an idea of what a trigger point is and why they can increase pain and dysfunction, let’s look at some of the causes. The all-encompassing cause of trigger point development is defined as “neuromuscular dysfunction of skeletal muscle” (1). This simply means that normal muscle activity is not occurring. The not so simple part is determining where along the path the abnormality lies.
Causes of Trigger Points:
Can be caused by overactive muscles that fatigue, such as when we hunch our shoulders and our upper traps become sore. It can be due to underactive, weak muscles that aren’t stimulated enough leading to less metabolic activity (blood flow and waste clearance), more fluid or swelling, and abnormal load on surrounding tissue (compensation). Then when we go to use the muscle, it responds poorly. Think of a weak shoulder blade area and the pain that can develop around it. Often times muscle function is intertwined with joint function, or structural positioning. If our joints are not "centralized," meaning optimal position for movement according to each person's unique makeup (there's a textbook normal as well as real-life subtleties), then the muscles can become out of balance.
Trigger points can also arise from an acute injury, such as getting hit with a baseball, and the inflammatory cascade that ensues. Unless the area heals properly, it can become a common site for future problems and muscle dysfunction.
Trigger point development is very often caused by micro-trauma or chronic, repetitive inflammation (similar to overactive except spread out over time and undetectable until a certain breaking point). Unlike getting hit with a baseball, which we feel immediately, micro-trauma occurs at the cellular level and is not felt, sometimes for years, until we suddenly start to have symptoms. This happens with certain jobs and positions we find ourselves in over and over again. Take for instance the typical desk worker. They are usually working on a computer or looking down at a desk. This places a lot of stress or load on the neck and upper back muscles (in order to support the head, which weighs about 8 to 10 lbs). Over time, these muscles become overworked and fatigued, and trigger points can develop.
Beyond the muscles themselves, there may also be dysfunction occurring within the nervous system, most commonly at the motor endplate (where the controlling nerve enters the muscle) but possibly anywhere along the nerve pathway. As we already discussed, increase in acetylcholine at the motor endplate can cause hyper activity and trigger point formation. Furthermore, our diet, which influences the level of inflammation (pro-inflammatory versus anti-inflammatory), can make us more or less susceptible to trigger point development and the capacity to resolve or heal them.
As we can see there are several possible culprits as to what causes skeletal muscle dysfunction, but how do we treat them?
There are several things that we can do for ourselves to help reduce trigger point activity. First, and most importantly, we must adopt better posture and movement patterns. This means trying to prevent them from forming in the first place, and, if they are already present, then reducing the size and activity of them. For instance, if you work at a desk, get up periodically and take a short walk or get a thera-band and look up exercises you can perform in a chair (we will share videos on this in the future). If you find yourself in repetitive patterns, such as always turning your head one way (overuse on one side) then break up the pattern or counter it by turning the other way and seeing how it feels. Try to maintain balance and symmetry (it often helps to use a mirror to compare side to side) – look out for asymmetry in the shoulders, head, hips and feet.
We can also self-treat trigger points by using a lacrosse-type ball (hard rubber ball). Simply apply pressure to these points and try to stimulate them. By stimulating them with pressure, we are trying to improve blood flow as well as release tension in the area. It may help to change the length of the muscle (short/contracted versus long/relaxed) to see how it affects the sensation. It definitely requires a bit of skill to target the specific area and apply the right pressure but it becomes easier with practice. Depending on the location of the trigger point, it may be easier to lay on the floor or else try standing and using the wall. This type of care can be painful during but it is usually accompanied with relief shortly afterwards. **Check out this quick video (https://youtu.be/mWxM0QCBCVM) on how to target the upper trap and levator muscles (common culprits of trigger points) utilizing this technique.
If self-care isn’t doing the trick, then look at getting treated by a professional. Some of the treatments we utilize in our office include:
o Focuses on improving structure and position of joints, as well as nerve function, ensuring better control of muscles.
- Active Release Technique
o A method that applies direct pressure and takes the muscle through a range of motion, from a contracted position to a lengthened one. This helps reduce hypercontracted fibers, normalize movement, and reduce pain.
o Inserting a needle into the trigger point causes a local inflammatory response and helps release the contracted knot or tension. It helps reduce pain by clearing out the sensitizing substances and promotes healing of muscle tissue. Often times there is a local twitch response when the trigger point is released, resulting in pain relief.
- Instrument-Assisted Soft Tissue Technique
o Using a stainless steel tool, we are able to increase depth and pressure to reach trigger points and adhesive muscles. It helps normalize muscle fibers, scar tissue, and other connective tissue. This is especially useful following acute injury (during the remodeling phase of tissue healing) – which leads to the formation of scar tissue and decreased mobility. This technique helps improve mobility and reduce the chance of future injury.
One thing is certain, we have all experienced trigger points and muscular type pain. Depending on how involved, and how well we care for ourselves, will determine the level of severity and what we need to do moving forward. If you live in pain on a regular basis or are limited from doing certain activities, then seek a professionals help and start the path to recovery. Often times all that is required to feel 85 percent better is 4 to 6 sessions. If you have occasional pain without limitations, then consider adding some self care techniques to your daily routine. One thing to point out: pain is usually the last thing to show up and the first thing to go. If you are having pain, the underlying cause has likely been present for much longer. Correcting the cause will lead to long term solutions and prevention.
1. Ma, Yun-tao. (2011). CHAPTER 10. Trigger Points and the Integrative Neuromuscular Acu-Reflex Point System. 10.1016/B978-1-4377-0927-8.00010-5.
Dr. Nick specializes in human movement and performance, helping individuals live more active, pain-free lifestyles!