Myofascial Pain Syndrome
What is myofascial pain syndrome?
Myofascial pain syndrome is a pain condition that affects your muscles and fascia. “Myo” means muscle and “fascial” means fascia. Your fascia is the thin, white connective tissue that is wrapped around every muscle.
Here’s an easy visual: If your body was an orange, your skin would be the outside orange peel, your muscles would be the fleshy orange fruit itself and the thin white membrane surrounding each orange segment would be the fascia. Fascia surrounds every level of muscle tissue —muscle fibers, single muscles and muscle groups.
Muscle pain isn't picky — it can strike anyone at any time in their life. Everyone from the mother carrying her child and the roofer laying shingles to the best friend helping lift boxes during a move can experience muscle pain. Unfortunately, for some people, this pain can be unbearable and it sticks around long after it should have faded. If you experience muscle pain that won't go away for a long period of time, it could be myofascial pain.
What does the fascia do?
Simply put, your fascia holds your muscles together, which allows them to contract and stretch. Fascia also provides a slick surface so that individual muscle fibers, single muscles and muscle groups can slide against each other without creating friction, tearing or causing other problems.
Actually, fascia is everywhere inside your body. Besides your muscles, all organs and blood vessels are connected to or surrounded by fascia. Fascia is a complex substance. It contains nerve endings. Scientists are still discovering all of the functions and roles of fascia.
What happens when a person experiences myofascial pain syndrome? How does it start?
Myofascial pain is a common syndrome. If you have myofascial pain syndrome, you may feel pain and tenderness in muscles in a certain area of your body. This pain and tenderness is often related to one or more “trigger points.” To the touch, trigger points feel like small bumps, nodules or knots in your muscle.
If you could look at a trigger point under a microscope, you’d see that it lies within a taut band, which is a tight strand of muscle that feels like a cord or tendon. The trigger point itself — the “knot” — is actually many nearby segments of muscle fibers that are stuck in the contracted state.
When muscle fibers are stuck in contraction, blood flow stops. If blood flow to the area stops, that area of muscle is not getting the oxygen it needs. Waste materials also build up in these fibers. This irritates the trigger point, which reacts by sending out a pain signal. Your brain responds by telling you not to use that muscle. Lack of use actually causes the muscle to tighten, become weak and it causes a loss in your range of motion. Muscles around the affected muscle have to work harder to do the work of the affected muscle. Trigger points can develop in these muscles too and add to the localized pain you feel.
Trigger points can develop in all muscles, and in many muscles at the same time. This is one of the reasons why it may seem like your pain in shifting or moving around. Trigger points can also be tricky in that pain can occur at the site of the trigger point (when lightly pressed) or cause pain in a nearby area. This is called referred pain.
How common is myofascial pain syndrome?
Myofascial pain occurs in about 85% of people sometime during their life. Even this high percentage may not be accurate. Myofascial pain is often underdiagnosed, misdiagnosed or overlooked because it’s hidden in another type of diagnosis such as headache, neck and shoulder pain, pelvic pain, limb pain or nerve pain syndrome.
Men and women are equally affected, though middle-aged inactive women are at the highest risk.
Where does myofascial pain syndrome most commonly occur?
Myofascial pain and trigger points can develop in any muscle in the body. However, the most commonly affected muscles are those in the upper back, shoulder and neck. These muscles include the:
- Sternocleidomastoid: This large muscle helps rotate your head to the opposite side and flexes your neck. It is located on both sides of your neck, running from your skull behind your ear area to your collarbone and breast bone.
- Trapezius: This large, broad, flat triangular back muscle tilts and turns your head and neck, shrugs and steadies your shoulders, and twists your arms. The muscle extends from the base of your skull to the middle of your back.
- Levator scapulae: This pair of strap-like muscles help raise and rotate each of your shoulder blades. They run from the first four cervical vertebra to the top edge of your shoulder.
- Infraspinatus: This triangular muscle, located on the back side of each of your shoulder blades, helps rotate and stabilize your shoulder joints. It’s one of four muscles of the rotator cuff.
- Rhomboids: This pair of upper back muscles pull your shoulder blades together when they contract and attach the upper limbs to your shoulder blade. These muscles run diagonally from the neck and chest vertebrae of the spine down to the back of the shoulder blades.
What are the symptoms of myofascial pain syndrome?
Symptoms are different for each person with myofascial pain syndrome. Sometimes the pain happens suddenly and all at once, and that is called a “flare-up” of symptoms. At other times it’s a constant, dull pain that sort of lingers in the background.
Symptoms of myofascial pain syndrome include:
- Pain that’s described as deep aching, throbbing, tight, stiff or vice-like.
- Trigger points (a small bump, nodule or knot in the muscle that causes pain when touched and sometimes when it’s not touched).
- Muscles that are tender or sore.
- Weakness in the affected muscle(s).
- Reduced range of motion in the affected areas (e.g., you may be unable to completely rotate your shoulder).
People with myofascial pain syndrome often have other health problems that coincide. Commonly reported problems include:
- Poor sleep.
- Stress, anxiety, depression.
- Feeling tired (fatigue).
What causes myofascial pain syndrome?
The jury is still out about all of the causes, contributing factors and exactly how the pain mechanism works.
Causes of myofascial pain syndrome include:
- Muscle injury.
- Muscle strain/repetitive muscle use (e.g. hammering).
- Muscle weakness/lack of muscle activity (e.g. a leg in a cast will not get enough movement).
- Poor posture.
- Working in or living in a cold environment.
- Emotional stress (can cause muscle tension).
- Pinched nerve.
Other factors thought to contribute to the development of myofascial pain syndrome include:
- Metabolic or hormonal problems such as thyroid disease or diabetic neuropathy.
- Vitamin deficiencies, including vitamin D and folate.
- Presence of chronic infections.
Is myofascial pain syndrome an autoimmune disease?
It is not. Inflammation of the muscle or fascia is not caused by your body’s immune system incorrectly attacking healthy cells. Examples of autoimmune diseases are lupus, type 1 diabetes, celiac disease and multiple sclerosis.