Fascia

Fascia
Fascia
	The rectus sheath (extensive vertical darker gray at left), an example of a fascia
Details
Precursor	Mesenchyme
Identifiers
Latin	fascia
MeSH	D005205
TA98	A04.0.00.031
TA2	2015
FMA	78550
	Anatomical terminology [edit on Wikidata]

A fascia (/ˈfæʃ(i)ə/; pl.: fasciae /ˈfæʃii/ or fascias;^[1] adjective fascial; from Latin: "band") is a generic term for macroscopic membranous bodily structures.^[2]^: 42 Fasciae are classified as superficial, visceral or deep, and further designated according to their anatomical location.^[3]

The knowledge of fascial structures is essential in surgery, as they create borders for infectious processes (for example Psoas abscess) and haematoma. An increase in pressure may result in a compartment syndrome, where a prompt fasciotomy may be necessary. For this reason, profound descriptions of fascial structures are available in anatomical literature from the 19th century.

Function

Fasciae were traditionally thought of as passive structures that transmit mechanical tension generated by muscular activities or external forces throughout the body. An important function of muscle fasciae is to reduce friction of muscular force. In doing so, fasciae provide a supportive and movable wrapping for nerves and blood vessels as they pass through and between muscles.^[4]

Fascial tissues are frequently innervated by sensory nerve endings. These include myelinated as well as unmyelinated nerves. Research indicates that fascia has proprioceptive (the ability to determine the body's orientation with respect to itself) as well as interoceptive (the ability to discern sensations within the body like the heartbeat) capabilities.^[5]

Fascial tissues – particularly those with tendinous or aponeurotic properties – are also able to store and release elastic potential energy.

Anatomical compartments

A fascial compartment is a section within the body that contains muscles and nerves and is surrounded by fascia. In the human body, the limbs can each be divided into two segments: The upper limb can be divided into the arm and the forearm and the sectional compartments of both of these – the fascial compartments of the arm and the fascial compartments of the forearm contain an anterior and a posterior compartment. The lower limbs can be divided into two segments – the leg and the thigh – and these contain the fascial compartments of the leg and the fascial compartments of the thigh.

Clinical significance

Fascia itself becomes clinically important when it loses stiffness, becomes too stiff, or has decreased shearing ability.^[6] When inflammatory fasciitis or trauma causes fibrosis and adhesions, fascial tissue fails to differentiate the adjacent structures effectively. This can happen after surgery, where the fascia has been incised and healing includes a scar that traverses the surrounding structures.

Terminology

There exists some controversy about what structures are considered "fascia" and how they should be classified.^[7]^[8]

The current version of the International Federation of Associations of Anatomists divides into:^[7]

Fascia craniocervicalis
Fascia trunci
- Fascia parietalis
- Fascia extraserosalis
- Fascia visceralis
Fasciae membrorum
Fasciae musculorum
- Fascia investiens
- Fascia propria musculi

Previous terminology

Two former, rather commonly used systems are:

The one specified in the 1983 edition of Nomina Anatomica (NA 1983)
The one specified in the 1997 edition of Terminologia Anatomica (TA 1997)

NA 1983	TA 1997	Description	Example
Superficial fascia	(not considered fascia in this system)	This is found in the subcutis in most regions of the body, blending with the reticular layer of the dermis.^[9]	Fascia of Scarpa
Deep fascia	Fascia of muscles	This is the dense fibrous connective tissue that interpenetrates and surrounds the muscles, bones, nerves and blood vessels of the body.	Transverse fascia
Visceral fascia	Visceral fascia, parietal fascia	This suspends the organs within their cavities and wraps them in layers of connective tissue membranes.	Pericardium

Superficial

Superficial fascia is the lowermost layer of the skin in nearly all of the regions of the body, that blends with the reticular dermis layer.^[10] It is present on the face, over the upper portion of the sternocleidomastoid, at the nape of the neck and overlying the breastbone.^[11] It consists mainly of loose areolar and fatty adipose connective tissue and is the layer that primarily determines the shape of a body.^{[medical citation needed]} In addition to its subcutaneous presence, superficial fascia surrounds organs, glands and neurovascular bundles, and fills otherwise empty space at many other locations. It serves as a storage medium of fat and water; as a passageway for lymph, nerve and blood vessels; and as a protective padding to cushion and insulate.^[12]

Superficial fascia is present, but does not contain fat, in the eyelid, ear, scrotum, penis and clitoris.^[13]

Due to its viscoelastic properties, superficial fascia can stretch to accommodate the deposition of adipose that accompanies both ordinary and prenatal weight gain. After pregnancy and weight loss, the superficial fascia slowly reverts to its original level of tension.

Visceral

Visceral fascia (also called subserous fascia) suspends the organs within their cavities and wraps them in layers of connective tissue membranes. Each of the organs is covered in a double layer of fascia; these layers are separated by a thin serous membrane.

The outermost wall of the organ is known as the parietal layer
The skin of the organ is known as the visceral layer. The organs have specialized names for their visceral fasciae. In the brain, they are known as meninges; in the heart they are known as pericardia; in the lungs, they are known as pleurae; and in the abdomen, they are known as peritonea.^[14]

Visceral fascia is less extensible than superficial fascia. Due to its suspensory role for the organs, it needs to maintain its tone rather consistently. If it is too lax, it contributes to organ prolapse, yet if it is hypertonic, it restricts proper organ motility.^[15]

Deep

Deep fascia is a layer of dense fibrous connective tissue which surrounds individual muscles and divides groups of muscles into fascial compartments. This fascia has a high density of elastin fibre that determines its extensibility or resilience.^[16] Deep fascia was originally considered to be essentially avascular but later investigations have confirmed a rich presence of thin blood vessels.^[17] Deep fascia is also richly supplied with sensory receptors.^[18] Examples of deep fascia are fascia lata, fascia cruris, brachial fascia, plantar fascia, thoracolumbar fascia and Buck's fascia.

References

^ "Definition of FASCIA". www.merriam-webster.com. Retrieved 12 August 2022.
^ Standring, Susan (2020). Gray's Anatomy: The Anatomical Basis of Clinical Practice (42nd ed.). New York. ISBN 978-0-7020-7707-4. OCLC 1201341621.{{cite book}}: CS1 maint: location missing publisher (link)
^ Gatt, Adrianna; Agarwal, Sanjay; Zito, Patrick M. (2023), "Anatomy, Fascia Layers", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 30252294, retrieved 2023-05-16
^ Faller, A.; Schuenke, M. (2004). The Human Body. Thieme Medical Publishers. p. 127.
^ Langevin, Helene M. 2021. "Fascia Mobility, Proprioception, and Myofascial Pain" Life 11, no. 7: 668. https://doi.org/10.3390/life11070668
^ Klingler, W.; Velders, M.; Hoppe, K.; Pedro, M.; Schleip, R. (2014). "Clinical relevance of fascial tissue and dysfunctions". Curr Pain Headache Rep. 18 (8): 439. doi:10.1007/s11916-014-0439-y. PMID 24962403. S2CID 4217127.
^ ^a ^b "Terminologica anatomia humana. A04.0.00.031: fascia". ifaa.unifr.ch. International Federation of Associations of Anatomists. 2013-01-29. Retrieved 2024-03-23.
^ Committee on Anatomical Termi, Federative (1998). Terminologia Anatomica: International Anatomical Terminology. Thieme Stuttgart. p. 33. ISBN 3-13-114361-4.It is acknowledged that the various definitions of fascia offered by recognised authorities do not enjoy universal agreement and all have varying deficiencies. These definitions currently fall short of an agreed, descriptive, fully embracing definition that would suit all interested medical agencies/researchers and allied disciplines (16).
^ Skandalakis, John E.; Skandalakis, P.N.; Skandalakis, L.J.; Skandalakis, J. (2002). Surgical Anatomy and Technique, 2nd Ed. Atlanta, GA: Springer. pp. 1–2. ISBN 0-387-98752-5.
^ Skandalakis, John E.; Skandalakis, P.N.; Skandalakis, L.J.; Skandalakis, J. (2002). Surgical Anatomy and Technique, 2nd Ed. Atlanta, GA: Springer. pp. 1–2. ISBN 0-387-98752-5.
^ Paoletti, Serge (2006). The Fasciae: Anatomy, Dysfunction & Treatment. Seattle, WA: Eastland Press. pp. 23–24. ISBN 0-939616-53-X.
^ Hedley, Gil (2005). The Integral Anatomy Series Vol. 1: Skin and Superficial fascia.
^ Norman Eizenberg, General Anatomy:Principles and Applications (2008), p 70.
^ Hedley, Gil (2005). The Integral Anatomy Series Vol. 3: Cranial and Visceral Fasciae (DVD). Integral Anatomy Productions. Retrieved 2006-07-17.
^ Paoletti, Serge (2006). The Fasciae: Anatomy, Dysfunction & Treatment. Seattle, WA: Eastland Press. pp. 146–147. ISBN 0-939616-53-X.
^ Hedley, Gil (2005). The Integral Anatomy Series Vol. 2: Deep Fascia and Muscle (DVD). Integral Anatomy Productions. Retrieved 2006-07-17.
^ Stecco, Carla (2015). Functional Atlas of the Human Fascial System. Edinburgh, UK: Churchill Livingstone Elsevier. p. 59. ISBN 978-0-7020-4430-4.
^ Schleip, Robert (2003). "Fascial plasticity – a new neurobiological explanation: Part 1". Journal of Bodywork and Movement Therapies. 7 (1): 11–9. doi:10.1016/S1360-8592(02)00067-0.