Introduction to Myofascial Pain

Introduction

Fascia: Consists of solid and liquid components.

• Solid components : muscle, bone , cartilage and adipose tissue.
• Liquid components include: blood and lymph.

Myofascia: includes contractile muscle and connective tissues. End thickenings make origins and insertions of the muscles on the bones. Thus able to guide the skeletal system with muscular contractions.(1)

The nerve, vascular and lymphatic system are enclosed in multiple layers of fascia. Thus different tissues are linked together by the fascia.

• The fascia creates different interdependent layers with several depths, from the skin to the bone
• The fascia creates different interdependent layers with several depths, from the skin to the periosteum, forming a three-dimensional mechano-metabolic structure .
• The liquid fascia (blood and lymph) can be a source of pain, because changes in flow velocity, direction, and type of flow, can affect surrounding tissues, thereby leading to myofascial pain.
• Myofascial pain,can due to any of the structure tangled in the myofacia : nerves, muscles, connective tissue and so on.an be a source of pain, because changes in flow velocity, direction, and type of flow, can affect surrounding tissues, thereby leading to myofascial pain.

Myofascial pain,can due to any of the structure tangled in the myofacia : nerves, muscles, connective tissue and so on.

Causes of Myofascial Pain

1. Trigger points : active or latent. (Fricton J. Myofascial Pain: Mechanisms to Management. Oral Maxillofac Surg Clin North Am. 2016 Aug;28(3):289-311)
2. Active : pain without movement
3. Latent: painful with palpation, Vague, non localised

Hypotheses for Myofascial pain

1. Constant microtrauma to the muscle→ depletes ATP → alters mechano-metabolic environment → increases nociceptive impulses to the brain→ peripheral sensitization in acute phase and central sensitization chronically (2).  (potassium, prostaglandins, histamine, kinins, ) Increase in Ach at synaptic end plate→ continuous contraction→ depletes ATP → inflammation . ( Friction, 2016)
2. Change in connective tissue due to inflammation →  fibroblasts transform to myofibroblasts → shortening of tissue and increase in tone→ nociceptive stimulus → alters polarization of muscle fibers → muscle contraction. (Bordoni B, Marelli F, Morabito B, Castagna R. Chest pain in patients with COPD: the fascia's subtle silence. Int J Chron Obstruct Pulmon Dis. 2018;13:1157-1165)
3. Altered mechanometabolic environment → thickening of extracellular matrix → fascia difficulty sliding→ harder for muscle to contract ( stecco, stern et al 2013)→ The nerve endings of the fascia in the most viscous area stretches, becoming constantly activated, creating a trigger point. ( Stecco, Stern et al 2011).
4. Alteration of blood flow ( increase in systolic velocity, decrease in diastolic velocity) → alters morphology and function of capillaries→ ischemia → activate type IV nerve endings → myofascial pain. (Bron C, Dommerholt JD. Etiology of myofascial trigger points. Curr Pain Headache Rep. 2012 Oct;16(5):439-44.)

Differential Diagnosis for Myofascial pain

• Fibromyalgia: some studies highlight an alteration of the connective tissue with the stem cells that produce adipose tissue. The myofascial pain could cause an inflammatory environment and local pain. Fibromyalgia is not localized;(3)  

• •The chronic pelvic pain: condition that must be present from 6 months onwards, and not necessarily influenced by movements or the presence of menstruation (in women). Ultrasound examinations to determine muscular processes v/s organic dysfunctions. Montenegro,Gomide, et al

• •The temporomandibular joint could be involved in myofascial pain but could also be involved in a referred pain pattern. If there are trigger points that do not improve after a manual or pharmacological approach, it could be a symptom of cardiac ischemia. (4)
• Throat or neck pain, if unilateral, could be caused by Eagle's Syndrome. Pain should improve with tissue treatment; if this does not happen, the causes must be investigated.(5)
• Inflammations of tendons or inflammations of purely connective formations (fasciitis, tendinopathies, and more) have a very specific anatomical area.

Table of history...

Mechanical	Psychological	Systemic/ metabolic	Other
Scoliosis	Stress	Hypothyroidism	Infectious ds
Limb length discrpency	Anxiety	Fe Def	Parasitic ds
Muscle hypertrophy		Vit D def	Rheumatic ds
Repetitive microtrauma		Vit c def	Hyperalgesia
		Vit B12 def	Statins