I was upset there wasn’t a question on fascia in my exam today, since it’s such an interesting topic and I’ve been revising so much about it. So I’ve decided to impart some of my knowledge on the subject via this post:
Fascia is an amazing and vital structure of mammalian bodies. It is a critical part of the horse and an important structure to recognise and understand as a physiotherapist. Despite its importance, little is known about fascia and limited research has been conducted on the matter.
Fascia is a connective tissue which surrounds and separates pretty much everything in the body. Fascia is found around bones (periosteum), surrounding the CNS (dural fascia, eg. arachnoid mater), blood vessels, hypodermis (superficial fascia), surrounding muscles (epimysium), surrounding every cell etc. and is continuous throughout the entire body.
Fascia itself is an 3D elasto-collagenous web, suspended in an extracellular matrix (ECM) containing proteoglycans, lubricin and hyaluronan amongst other metabolites. Interestingly, fascia is piezolelectric in that it is able to conduct ion changes similarly and comparatively to the nervous system (Langevin et al., 2006). It is also rich in nerve endings, allowing it to serve as a sensory organ.
The fascial web, suspended in ECM, is constructed of collagen and elastin fibres which form dynamic links with eachother. Collagen is critical in the tensile strength of the fascia, and has microtubules filled with crystalline saline solution to allow its capacity to withstand multidirectional forces and maintain structure. Elastin is important in the tensegrity model of maintaining structures in place, allowing structures to be deformed with load and elastically recoil to original position. Proteoglycans are made up of a core protein with numerous sulphated glycosaminoglycans (GAGs) attached. GAGs are highly negatively charged, thereby being highly hydrophilic and attracting water molecules. This means that fascia serves as an important water reservoir in the body, providing hydration for surrounding tissues. It also means that fascia has great compressional strength, enabling it to withstand and dissipate concussion forces.
Injury to fascia is often associated with acute inflammatory phase of injury in nearby tissues. Tissue injury is often dealt with by the body by recruiting proteoglycans from fascia to allow nearby tissue repair. This results in reduced proteoglycan content of fascia and subsequent dehydration and loss of compressional strength. Dehydration extends through the elasto-collagenous web, causing it to become dense and fibrotic as the crystalline saline solution of collagen solidifies. There is also increased cross-linking between elastin and collagen fibres, causing adhesions, increasing friction between structures.
This ‘clamp down’ in fascia creates focal and eventually global restrictions, pulling on bony attachments and eventually causing postural misalignement and eventual atrophy. The clamp down also causes nerve ending irritation, which causes hypersensitivity and pain.
Treatment of fascial injury is varied, and includes:
- Myofascial release
- Anti-inflammatory treatment
- Crystalline saline injection