Fascinating Fascia
January 25, 2020
For about 10 years, the anatomical structure known as fascia has been talked about everywhere. Fascia rollers, fascia balls, fascia massage, fascial distortion model (FDM), fascia yoga, etc... but what exactly are these fascias?
Fascias are a connective tissue matrix that encompasses all our body structures (muscles, ligaments, bones, joints, nerves, blood vessels, and organs) like packaging. This way, the fascias give us our shape (body) and serve as the first layer of protection against external forces.
Frank Liebig creator QS:P170,Q29586018, Spiderweb in fir top, CC BY-SA 3.0 DE
Structure of the Fascias
The body's fascia can be divided into four different layers. The outermost layer just under the skin forms the pannicular fascia, often referred to as the superficial fascia. The pannicular fascia is mainly made up of loose connective tissue and fat and covers our entire body (torso, arms, and legs) except for body openings like the mouth, eyes, nose, etc.
The second layer is formed by the trunk fascia (deep fascia or muscular fascia). Similar to the pannicular fascia, the trunk fascia develops from embryonic mesenchyme. It forms the primitive matrix in which all skeletal muscles, bones, tendons, ligaments and joints arise during embryonic development. In the arms and legs, the trunk fascia is usually referred to as muscular fascia - but the function remains the same: The dense mesh-like connective tissue serves as a protective and sliding layer of the musculoskeletal system and transfers a part of the force at the joints during muscle contraction.
The third and fourth fascia layers are enclosed by the trunk fascia and are known as meningeal and visceral fascia. The meningeal fascia surrounds and protects our nervous system, while the visceral fascia acts as protection and suspension for our internal organs.
The important point to note here is that these four layers are not to be seen as separate systems but as a unified continuum of tissue structures.
The body fascia, like the joint capsules and the intramuscular and intraneural septa, belong to the unformed (mesh-like), dense connective and supporting tissues of our body. Tendons and ligaments, on the other hand, consist of formed (parallel-fibered) connective tissue. The difference lies in the arrangement of collagen fibers in the tissues – as a reaction to tensions acting in various directions, collagen fibers in the unformed, dense connective tissue create networks that can also shift and unfold in different directions. In formed connective tissue, all fibers are always aligned in the same direction – they run parallel to each other due to the constant strain. Therefore, fascias are much more flexible and mobile compared to ligaments.
In principle, both unformed and formed connective tissues are made up of the same building blocks – cells and extracellular matrix. The cells are divided into fibroblasts/-cytes, chondroblasts/-cytes, and osteoblasts/-cytes. Which type of tissue the connective tissue develops into depends on the mechanical demands placed on the tissue or mesenchymal cells.
If tensile forces predominantly act on the tissue, mostly fibroblasts develop, which in turn produce primarily Type-I collagen fibers and very little elastic ground substance, i.e., tendons and ligaments develop. However, when pressure predominantly affects the tissue, mostly chondroblasts develop, which exclusively produce ground substance and only very thin Type-II collagen fibrils. This is typically found in hyaline joint cartilage.
In fascia tissue, primarily fibroblasts develop. Although they contribute only a small portion to the volume of fascia, they have an important role in its structure and stiffness. The tasks of fibroblasts include the production of most components that form the extracellular matrix – except for the large amount of water in the fascia – and the repair of tissue injuries during wound healing.
Alongside fibroblasts, adipocytes (fat cells) are also found in fascia tissue. Adipocytes play not only a crucial role in estrogen production but also act as important producers of various peptides and cytokines, which are responsible for appetite, insulin, and blood sugar regulation, as well as angiogenesis (growth of blood vessels), vasoconstriction (narrowing of blood vessels), and blood clotting – vital substances during wound healing. In the fascia, adipocytes are densely located in numbers in areas with high shear forces and gliding movements, providing padding there.
Studies have shown that many different types of receptors are found within the fascia. These include myelinated proprioceptive as well as various unmyelinated "free" nerve endings. These nerve endings deliver important signals for controlling movement and posture (proprioception) to our brain, where the conscious and unconscious perception of body posture and movement is formed in conjunction with information from other sources of our body. When considering the number of receptors in fascia tissue, it is likely as large, if not larger than the number of receptors in the retina (the eye's retina). Thus, it's well imagined that fascia is one of our most important sensory organs!
An effective overview of the structure and function of the fascia was provided by French hand surgeon Dr. Jean-Claude Guimberteau. Intraoperatively, he examined via endoscope how the fibers of the fascia move and behave. In his film "Strolling under the skin" one gets a wonderful insight beneath the skin.
"PROMENADES SOUS LA PEAU OU A la découverte des architectures de la matière vivante", Dr. Jean-Claude Guimberteau
Role & Function of the Fascias
Besides acting as a sensory organ, fascia must be able to swiftly deform in various directions and planes and quickly return to its original shape – because fascia serves as the first shield against external forces. Our muscles, bones, and joints generally cannot endure much direct contact without breaking. Especially to prevent muscle injuries (like muscle tears), the fascia must act immediately as a shock absorber under large, quick forces since the muscles themselves are too slow to prevent injury.
Unilateral, one-dimensional movements can lead to adhesions in the fascia. These are known as crosslinks. Consequently, the fascia loses some of its displacement capacity. Thus, as mentioned above, it cannot fully absorb force impact, potentially causing a muscle tear.
Apart from its protective role, due to its layered arrangement, fascia serves as a gliding and displacement layer. One can imagine that individual nerves, arteries, veins, muscles, and even muscle groups are surrounded and separated from each other by fascia. The fascia thereby enables movement between the individual structures in our body.
Furthermore, this architecture of fascia supports the muscles in force transmission between muscles, muscle groups, and joints during movement and sports – work is conducted in so-called myofascial chains. These chains are named differently by various authors, yet they all share something in common: every muscle group requires a basis to fulfill its function. This basis comprises other muscle groups, further stabilized by additional muscle groups, etc. Certain therapy forms, like proprioceptive neuromuscular facilitation (PNF) by Dr. Herman Kabat, are based on the theory of myofascial chains. This is a method for treating muscle paralysis in poliomyelitis. Here, the idea is that paralyzed muscles are activated in conjunction with/through other muscle chains.
Therapy
Why is fascia treatment so essential and effective? Imagine the fascia system as four layers of stockings intertwined with nerves, blood, and lymph vessels. These four stockings must be movable against each other in all directions to enable movement. Crosslinks between layers not only limit mobility but also directly affect the nerve, blood, and lymph systems.
If you now bring the stocking calf closer to the hand, as in the case of scar formation after surgery in fascia tissue, you can clearly observe how far the stocking stretches. Hence, it's no surprise that when there's an injury/restriction/scar, it can lead to problems in another section of the body across other joints.
During pain or movement limitations, it's crucial for a physiotherapist or osteopath to identify which structure houses the blockage or reduced mobility, to apply appropriately adjusted techniques to positively influence restrictions and pain, allowing the tissue to return to its normal state.
New research seems to confirm that fascias can contract and play a vital role in force development and transmission [1,2]. Moreover, they serve alongside muscles, tendons, and joints as an absorption mechanism for quick-acting forces. From our understanding, fascias should thus be considered and treated in connection with muscles. Based on complaints, training and therapy focus can be placed on specific structures, though as mentioned, they are closely interconnected such that the entire body gets trained. Manual therapeutic measures for treating fascial and muscular issues include fascial/connective tissue massage, myofascial release, FDM, trigger point and dry needling therapy, PNF, stretches, fascia rollers, etc.
Training Fascias
Fascias can and should be trained alongside the entire musculoskeletal system to ensure displacement and functionality. However, due to the anatomy and function, we find it very difficult to train the fascia alone: the entire neuro-muscular system gets trained. Essential is working in all dimensions and not just performing unilateral movements. Training forms like Pilates and Yoga are very beneficial, but jumps like in skipping rope are also helpful. Moreover, High Intensity Interval Training (HIIT) lends itself to fascial training methods. In HIIT, joints are more stressed than in Yoga and Pilates, therefore we recommend this form of training with support from a physiotherapist or personal trainer, meaning under guidance.
" Fascias - Mysterious world under the skin", all rights at arte.tv
If you need us, we're gladly here for you!
Your BodyLab Team - Your specialists for the musculoskeletal system
Osteopathy and Physiotherapy | Rehabilitation and Training
Zurich Altstetten
Literature References
Zügel M, Maganaris CN, Wilke J, et al.
Br J Sports Med 2018;52:1497.
[2] Are muscles mechanically independent?
Robert D. Herbert, Phu D. Hoang, and Simon C. Gandevia
J Appl Physiol 104: 1549–1550, 2008; doi:10.1152/japplphysiol.90511.2008.
Cover Image Credit
anonymous, Cross spider, web in backlight, marked as public domain, details on Wikimedia Commons
