The microvacuolar system: how connective tissue sliding works

Abstract

The term 'fascia' has been applied to a large number of very different tissues within the hand. These range from aligned ligamentous formations such as the longitudinal bands of the palmar fascia or Grayson's and Cleland's ligaments, to the loose packing tissues that surround all of the moving structures within the hand. In other parts of the body the terms 'superficial' and 'deep fascia' are often used but these have little application in the hand and fingers. Fascia can be divided into tissues that restrain motion, act as anchors for the skin, or provide lubrication and gliding. Whereas the deep fascia is preserved and easily characterized in anatomical dissection, the remaining fascial tissue is poorly described. Understanding its structure and dynamic anatomy may help improve outcomes after hand injury and disease. This review describes the sliding tissue of the hand or the 'microvacuolar system' and demonstrates how movement of tissues can occur with minimal distortion of the overlying skin while maintaining tissue continuity.

Biomechanical risk factors and flexor tendon frictional work in the cadaveric carpal tunnel

“…The SSCT loosely attaches the flexor tendons to the visceral synovium, and is comprised of collagen bundles that form adjacent layers interconnected by small perpendicular fibrils. During flexor tendon displacement, the SSCT is strained, with deep layers close to tendon moving before superficial layers near the visceral synovium (Guimberteau et al, 2010). Repetitive tendon motion is thought to promote shear damage at the tendon-SSCT interface, which is supported by the finding that fibrosis is exacerbated in SSCT layers adjacent to flexor tendon (Ettema et al, 2006;Schuind et al, 1990).…”

Clinical and symptomatological reflections: the fascial system

“…The transmission of the force is ensured by the fascial integrity, which is expressed by the motor activity produced; the tension produced by the sarcomeres results in muscle activity, using the various layers of the contractile districts (epimysium, perimysium, endomysium), with different directions and speed (Figure 2). 6,11,24,25…”

“…The most external layer is denominated subcutaneous fascia or loose (areolar) connective fascia 7,11. This layer is made up of several levels, each with variable amounts of fibroblasts (ie, connective cells) arranged in a disorderly manner and soaked in a gelatinous substance known as extracellular matrix, where numerous molecules (ie, glycosaminoglycans, proteoglycans and polysaccharides such as hyaluronic acid) can be found 3,12.…”

Fascia–Current knowledge and future directions in physiatry: Narrative review

“…The term "microvacuolar system" has been used to describe the types of connections between fascial structures visualized using fiberoptic cameras under the dermatological layers [30] that may allow sliding, but it is not a specific structure in itself. These connections were also examined using electron microscopy, and multiple polyhedral microvacuoles of different sizes and shapes were seen.…”

“…This microvacuolar system is thought to be composed primarily of proteoglycans [30]. Proteoglycans, specifically glycosaminoglycans, have a high density of negative charges and can thereby draw in water molecules, forming gels at very low concentrations [31][32].…”