Muscle Fiber Dysfunction and Trigger Points

This course discusses myofascial trigger points (muscle trigger points) and their relationship to muscle fiber dysfunction. A comprehensive systematic research review is included in this course discussing the prevalence, etiology, observable phenomenon, and pathobiology associated with trigger point development. This course also intends to clarify topics that have been obscured by myth and misinformation, including the definition of trigger points and referral pain patterns, the relationship between trigger points and continuous low-load stress (including posture), and the observable phenomenon that demonstrate the existence and accessibility of trigger points. Further, this course begins to detail the relationship between trigger points and myofascial pain syndrome, chronic whiplash syndrome, and fibromyalgia.

Movement professionals (personal trainers, fitness instructors, physical therapists, athletic trainers, massage therapists, chiropractors, occupational therapists, etc.) should consider this course as introductory, or foundational material for self-administered and manual release techniques. This course is part of our continued effort to build an evidence-based, integrated, systematic, patient-centered, and outcome-driven approach.

Additional Courses:

• Trigger Point Assessment and Palpation

Snippets from the Course:

Definitions

• Trigger Point - "A hyper-irritable spot in skeletal muscle that is associated with a hypersensitive palpable nodule in a taut band. The spot is painful on compression and can give rise to characteristic referred pain, referred tenderness, motor dysfunction, and autonomic phenomena (1)."

There has been some debate regarding the "existence" of trigger points and whether they represent a phenomenon that should be addressed. The debate stems from treating the term "trigger point" as a structural entity, rather than a characteristic set of symptoms as described by the creators of the term. That is, the term "trigger point" is similar to the label "low back pain", and not the label "herniated nucleus pulposus (HNP)". The gross majority of opposing views on trigger points are based on this common fallacy:

• Attack a term, based on the opposition's perceived definition of that term, rather than the expert's definition, published work, and/or intent for using the label.

Observable Phenomena Associated with Muscle Fiber Dysfunction:

• Increased tone (over-activity)
  • General increase in tissue density
  • Resistance to stretch
  • Changes in EMG activity
  • Changes in muscle spindle activity (H-reflex)
  • Twitch response
• Taut bands
• Palpable nodules
• Myalgia
  • Pain upon deep palpation
  • Latent trigger points (tender points)
  • Active trigger points
  • Referral pain
  • Diffuse myofascial pain and allodynia
• Centralization
  • Whiplash syndrome
  • Chronic low back pain
  • Fibromyalgia syndrome

Based on clinical observations, many of these phenomena may occur simultaneously. For example, pain on palpation is often associated with a general increase in tissue density and/or taut bands, with or without the presence of trigger points. Trigger points as defined above, likely represent a significant amount of muscle fiber dysfunction that includes maladaptation of the peripheral and central nervous system.