Fascia (temporarily) goes off the boil

Fascia was a ‘hot topic’ for the 19th century anatomists who strove to dissect and discuss the body’s newly visible fascial ‘parts.’ Fascia’s unprecedented visibility was largely due to the recent development of formalin-containing embalming fluids, which were enabling anatomists to slow down and take their time to examine, name, and describe many previously unspecified sections of fascia, or fasciae (as explained in my previous article). Yet, as the century drew to a close, the anatomy profession’s interest in fascia seemed to cool down … at least for a while. What could have caused this to happen?

In life, fascia’s ubiquitous ground substance is normally plump and transparent but it became abnormally dehydrated, dense, and opaque in anatomically dissected, embalmed cadavers … effectively concealing the things that it covers. This was problematic for the 20th century anatomists who couldn’t see through it to examine the things they wanted to study – like muscles and nerves. This led to them routinely removing and discarding the artificially sticky and opaque fascial tissue, a process they called (and still do) ‘cleaning’ the body. As a result, fascia was largely forgotten about and, from a ‘gross’ (topographic) anatomical viewpoint, was generally regarded as something that simply covers and contains the body’s other, presumably more valuable, parts (Gallaudet, 1931). Individual exceptions notwithstanding (e.g., Sterzi, 1910; Gallaudet, 1931; Singer, 1935; Stilwell, 1957), few anatomical reports explicitly pertained to the description of fascia. Fascia’s structure and physical properties were instead more often discussed in relation to their medical and surgical importance (e.g., Orrin, 1928; Bogduk & Macintosh, 1984).

The advent of the microscopic anatomy sub-discipline did little (if anything) to improve the 20th century anatomy profession’s relatively low opinion of fascia. The processes of histology (e.g., specimen acquisition, tissue fixation, use of microtomes to cut (section) thin slices of tissue, deparaffinizing, staining, and cover-slipping) enabled closer examination of fascial tissue. But ... these techniques also routinely dehydrated, distorted, and sometimes damaged the delicate and naturally hydrated fascial tissue – resulting in an unnaturally skewed view of it. Little wonder that fascia, which was vaguely categorised as a type of 'soft connective tissue,’ received very little explicit histological attention.

During the 20th century, fascia was widely recognized as an anatomical term, yet there was some international inconsistency about which parts of the body were acknowledged as fasciae, and the names by which they were known (Wendell-Smith, 1997; FCAT, 1998). Medical dictionaries typically defined fascia as a “sheet or band of fibrous tissue which covers the body under the skin and invests the muscles and certain organs” (Miller, 1947, p. 538). Yet, as Hollinshead explained (1954, p. 282), “there is no generally accepted definition as to how dense connective tissue must be before it can be regarded as forming a fascia, and … fascial spaces are simply areas of relatively loose connective tissue.” Others, including Le Gros Clark (1945) intrinsically regarded all loose connective tissue as fascia, noting this “material varies considerably in its consistency, in some places forming a very delicate retinaculum of loose texture, and in other places becoming condensed into a firmly woven feltwork or into tough fibrous sheets” (p. 31).

The custom of applying “a specific local term to any aggregation of connective tissue, sizeable enough to dissect” was challenged (Warwick & Williams, 1973, p. 490) by anatomists who observed that fascial tissue (syn. areolar tissue, connective tissue, connective tissue proper, fibrous tissue) and fascia are innately continuous. It was accordingly, and perhaps unsurprisingly, argued that …

?“the existence of a certain fascia may largely be a question of semantics [since] all connective tissue is continuous with all other connective tissue … [consequently] a fascia has no beginning and no end” (Rosse & Goddum-Rosse, 1997, p. 21).

The 20th century's relative anatomical and histological downplaying of fascia’s presence and importance inevitably resulted in this vital body element being barely mentioned in the education of many of the world’s medical students. And, unless they later became surgeons (who were generally taught more about it), fascia was seldom factored into their subsequent clinical reasoning, their research and textbook writing, their teaching and or their administrative decisions. Another (unfortunate) consequence of fascia’s general anatomical neglect was that it was barely, if ever, mentioned in the education of many other types of health professionals – including dentists, physiotherapists, and nurses - hence was effectively (and arbitrarily) excluded from their scopes of practice.

Fortunately this situation was beginning to change as the century drew to its close, when people all over the world - including, but not only, anatomists and surgeons - resumed talking about fascia as if it is important. In this way, fascia has metaphorically been returned to the stove and is now, yet again, feeling the heat associated with considerable amount of attention (which will be the subject of my next article).

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?If you are interested, you can learn some more about the relationship between anatomy, fascia and healthcare in my recently published (2021) book, The Living Wetsuit … and at www.sueadstrum.com

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References:

• Adstrum, S. (2022). Evolution of fascia-focused anatomy. Chapter 1.1 (pp. 4-19) in R. Schleip, C. Stecco, M. Driscoll, & P. Huijing (Eds.). Fascia: The tensional network of the human body (2nd edition). Edinburgh: Elsevier.
• Adstrum, S., & Nicolson, H. (2019). A history of fascia. Clinical Anatomy 23(7):862-870.
• Bogduk, N., & Macintosh, J. E. (1984). The applied anatomy of the thoracolumbar fascia. Spine 9(2):164-170.
• Federative Committee on Anatomical Terminology [FCAT] (Eds.). (1998). Terminologia anatomica: international anatomical terminology. New York: Thieme.
• Gallaudet, B. B. (1931). A description of the planes of fascia of the human body: with special reference to the fascia of the abdomen, pelvis and perineum. New York: Columbia University Press.
• Le Gros Clark, W. E. (1945). The tissues of the body: An introduction to the study of anatomy. Oxford, Clarendon Press.
• Miller, E. C. L. (Ed.). (1947). The American illustrated medical dictionary (21st ed.). Philadelphia: W.B. Saunders Company.
• Orrin, H. C. (1928). Fascial grafting in principle and practice: an illustrated manual of procedure and technique. Edinburgh: Oliver and Boyd.
• Rosse, C., & Goddum-Rosse, P. (1997). Hollinshead’s textbook of anatomy (5th ed.). Philadelphia, PA: Lippincott-Raven Publishers.
• Singer, E. (1935). Fasci? of the human body and their relations to the organs they envelop. Baltimore: Williams & Wilkins.
• Sterzi, G. (191O). Il tessuto sottocutaneo (tela subcutanea). Firenze: Luigi Niccolai.
• Stilwell, D. L. (1957). Regional variations in the innervation of deep fasciae and aponeuroses. The Anatomical Record 127(4):635-653.
• Warwick, R., & Williams, P. L (Eds.). (1973). Gray’s anatomy (35th ed.). London: Longman.
• Wendell-Smith, C. P. (1997). Fascia: An illustrative problem in international terminology. Surgical and Radiologic Anatomy 19(5):273-277.