Notes Made from The Following Studies;
Regularly asked questions in practise are "what are (muscle) knots?"
and " what causes them
Revising and digesting the two studies above on their pathology and physiology will hopefully answer those questions and give a good scientific knowledge as to why they occur.
Muscle "knots" are clinically known as myofascial trigger points (MTrP)
and there is great confusion over what they are. Terminology, theories, concepts, and diagnostic criteria are
inconsistent, incomplete, or controversial. What is Myofascial Pain Syndrome (MPS)?
- Shah et al.,
(2015) talks about myofascial pain syndrome (MPS) which is a fancy term used to describe painful muscle or surrounding connective tissue which can be acute (lasting less than 6 weeks) or chronic (lasting more than 3 to 6 months).
- MPS is an extremely common, but often overlooked
source of muscle pain, discomfort, and dysfunction (Hoyle, 2006).
- Myofascial pain is characterized by
contraction "knots" or "nodes" in the muscle that are hypersensitive on palpation, may
stimulate local and/or referred pain, may elicit a local twitch response and may be
eliminated by a local anesthetic or manual therapy.
- It is a complex disorder related to
the development of myofascial trigger points in muscle. These
myofascial TrPs have been further defined by their clinical characteristics as being either
"active" or "latent".
- An "active"
trigger point is associated with a clinical pain complaint.
- A "latent"
trigger point is tender on palpation and may be associated with restricted range
of motion and stiffness but is not associated with spontaneous complaints of pain (Hoyle, 2006).
"Fascia is classified by layer, as superficial fascia
, deep fascia
, and visceral
fascia, or by its function and anatomical location."
What is Myofascia?
The term “myofascial” describes how both muscle and fascia contribute to the symptoms. What Is A Myofascial Trigger Point (MTrP)?
- MTrPs are fined as "hard, discrete, hyperirritable, palpable nodules in a taut band of skeletal muscle that may be spontaneously painful (i.e. active) or painful only on compression" (Shah et al.,
- An active MTrP is clinically associated with spontaneous pain in the immediate surrounding tissue and/or to distant sites in specific referred pain patterns.
- Strong digital pressure on the active MTrP exacerbates the patient's spontaneous pain complaint and mimics the patient's familiar pain experience.
- MTrPs can also be classified as latent, i.e. lay "dormant" or "hidden" and asymptomatic as the MTrP is physically present but has not created a spontaneous pain complaint.
- However, pressure on the latent MTrP elicits local pain at the site of the nodule.
- Latent and active MTrPs can be associated with muscle dysfunction, weakness, and limited joint range of movement.
Critique to the Energy Deficit Theory
- There is no explanation or description for the initiating event that causes the excessive release of ACh to occur in the first place.
- This theory also assumes that the motor endplates are the focus of attention for trigger point development.
- There is no evidence suggesting that the endplates are responsible for trigger point development.
- This theory fails to explain why MTrPs are more prevalent at certain 15 muscle locations than others.
Muscle Overuse and What Happens When Hyaluronic Acid (HA) Levels Rise
- HA functions as a lubricant that helps muscle fibers glide between each other without friction.
- With muscle overuse or traumatic injury, the sliding layers start to produce immense amounts of HA which then aggregate into supermolecular structures
changing both its configuration, viscoelasticity and viscosity.
- Due to its increased viscosity, HA can no longer function as an effective lubricant which increases resistance in the sliding layers and leads to densification of fascia
or abnormal sliding in muscle fibers.
- Interference with sliding can impact range of motion and cause difficulty with movement, including quality of movement and stiffness. In addition, under abnormal conditions, the friction results in increased neural hyperstimulation (irritation), which then hypersensitizes mechanoreceptors and nociceptors embedded within the fascia.
- This hypersensitization correlates with a patient's experience of pain, allodynia, paresthesia, abnormal proprioception, and altered movement.
Marieb, Elaine Nicpon; Hoehn, Katja (2007). Human anatomy & physiology
. Pearson Education. p. 133. ISBN
Shah, J.P., Thaker, N., Heimur, J., et al. (2015) Myofascial Trigger Points Then & Now: A Historical and Scientific Perpective. Physical Medicine and Rehabilitation, 7:746-61.
J, Hoyle. (2006)EFFECTS OF POSTURAL AND VISUAL STRESSORS ON
TRIGGER POINT DEVELOPMENT, MUSCLE ACTIVITY, BLINK
RATE, AND DISCOMFORT DURING COMPUTER WORK, Ohio University, MSC.