What Causes Myofascial Pain Syndrome (MPS)?

Have you ever felt inexplicable nagging or lasting muscle pain in a specific body part, potentially accompanied by a small bump or knot under your skin, continued tenderness, and sleep deprivation? If so, you may be experiencing myofascial pain syndrome. Myofascial pain plays a vital role in avoiding injuries by alerting us to minor tissue damage.

When we are sore, it is usually because our muscles were subjected to a level of exertion past what they are used to, and the body is buying time to heal and adapt. The next time we attempt a similar activity, our body will be better prepared. If we ignore these warnings, we increase the risk of an overuse injury, from tendon inflammation to muscle tears.

But in some cases, muscle pain can continue long after the point of recovery, becoming chronic. This type of localized chronic muscle pain may be a sign of myofascial pain syndrome.

Defining Myofascial Pain Syndrome (MPS)

MPS as a condition is one that has not yet been thoroughly explored. Its etiology is evolving as research continues, and potential causes and treatments are still being identified. MPS main characteristics include lasting and unusual muscle pain, associated with so-called “trigger points” or “muscle knots,” as well as localized tenderness. The problem can be deep or stabbing and does not seem to improve on its own. Some of the signs of a trigger point include:

• • A bump under the skin.
  • Dull aching pain in the muscle (not necessarily near the joint or tendons).
  • Affected body parts feel heavier and weaker.
  • There is an apparent epicenter to your pain.
  • You cannot pinpoint the exact injury that caused your pain/it is chronic and has been recurring for months.
  • Flare-ups last days or weeks, at least.
  • Massages and warm baths seem to provide temporary relief.
  • You feel better after warming up or during/immediately after exercise.
  • The pain does not get better or worse, depending on the movements you perform.

In comparison to other common soft tissue pain syndromes, myofascial pain syndrome is asymmetrical and focal – which means it tends to exist in a specific area, such as the left shoulder, the right thigh, or the left portion of the lower back, and so on. It can exist in multiple areas at once, for different reasons.

Another common characteristic of MPS is “referred pain.” When a person’s trigger points or muscle knots are identified (they usually present as small bumps or pea-sized knots under the skin), pressing them may or may not eventually lead to relief and trigger referred pain in surrounding areas of the body.

For example, pressing on a lower back trigger might create a painful sensation further down in the buttocks or leg. Myofascial pain syndrome is not confused with delayed onset muscle soreness, which can occur over 24 hours after vigorous exercise and last several days. While MPS can be acute, the pain must persist for about three months to count as chronic.

Causes for MPS

Some studies find that myofascial pain syndrome correlates heavily with myofascial trigger points, which are individual clumps of muscle fiber that remain contracted. In contrast, the rest of the muscle is relaxed, like a mini cramp. Because these points remain contracted, they are often painful to the touch.

Explanations of MPS often point back towards these trigger points, explaining that they cut off or inhibit the blood supply to the surrounding nerves or tissues or accumulate waste metabolites from the cramping causes pain entire area. While individual trigger points are thought to be relatively common, MPS can present throughout specific areas of pain.

Trigger points are notoriously difficult to identify. Not every bump or abnormality is a trigger point. Lumps under the skin may be emerging pimples or cysts or features of normal anatomy that even experts can at times mislabel. Trigger points are a verifiable symptom of myofascial pain syndrome, but it is not clear how or why they occur or just how much they have to do with the other chronic pain symptoms in the area. Another explanation is that myofascial pain syndrome is a form of peripheral neuropathy.

The problem isn’t damaged or malfunctioning muscle, but the peripheral nervous system, leading to mini cramps and referred pain. If you believe your chronic muscle pain may be caused by or related to surrounding trigger points, it is worth bringing the idea up with a professional to explore trigger point treatments. These treatments might not necessarily get to the root of the syndrome but can lead to significant albeit temporary relief, often through massage therapy, heat therapy, and physical therapy.

How Is Myofascial Pain Syndrome Treated?

Physical therapy and massages can help manage pain related to trigger points, helping you through, especially severe flare-ups. Your pain might respond to certain medications better than others, and regular exercise seems to do wonders as well, ironically. Some medications that help deal with myofascial pain syndrome include:

• • Non-steroidal anti-inflammatory drugs
  • Nerve blocks
  • Muscle relaxants
  • Anticonvulsants
  • Botox injections

Aside from heat and massage therapy, other non-pharmacological treatments that have led to some success include:

• • Ultrasound therapy
  • Dry needling
  • Saline injections
  • Stretching
  • Posture improvements

However, there is no specific or universal treatment plan for myofascial pain syndrome. While trigger points and localized pain are primary features, patients with MPS may present with several other symptoms and potential conditions that require treatment, ranging from:

• • Generalized pain
  • Fibromyalgia
  • Osteoarthritis
  • Autoimmune conditions
  • Rheumatoid arthritis (RA)
  • And other causes of chronic pain

Co-occurring psychiatric conditions cannot be ignored and can massively impact the pain’s severity, especially anxiety disorders and mood disorders like depression. If you present with significant localized muscle pain that comes and goes for months, myofascial pain syndrome may be one of many potential explanations.