Fetal Fascial Reinforcement Development: From “a White Tablet” to a Sculpted Precise Organization by Movement

Abstract

Fasciae have received much attention in recent years due to their important role in proprioception and muscular force transmission, but few studies have focused on fetal fasciae development and there is no study on the retinacula. The latter are fascial reinforcements that play a key role in proprioception and motor coordination. Furthermore, it is still unclear if they are genetically determined or if they are defined by movements, and if they are present during gestation or if they appear only later in the childhood. We aim to identify their structural organization by qualitative and quantitative assessments to establish their role the myofascial development, highlighting their appearance and organization. Samples from the wrist retinacula, posterior forearm, ankle retinacula, anterior leg, iliotibial tract and anterior thigh of six fetus body donors (from 24th to 40th week of gestation) and histological sections were obtained and a gross anatomy dissection was performed. Sections were stained with hematoxylin-eosin to observe their overall structure and measure their thicknesses. Using Weigert Van Gieson, Alcian blue and immunostaining to detect Hyaluronic Acid Binding Protein (HABP), Collagens I and III (Col I and III) were realized to assess the presence of elastic fibers and hyaluronan. This study confirms that the deep fasciae initially do not have organized layers and it is not possible to highlight any reinforcement. The fascial development is different according to the various area: while the deep fascia and the iliotibial tract is already evident by the 27th week, the retinacula begin to be defined only at the end of pregnancy, and their complete maturation will probably be reached only after birth. These findings suggest that the movement models the retinacula, structuring the fascial system, in particular at the end of pregnancy and in the first months of life. The fasciae can be imagined, initially, as “white tablets” composed of few elastic fibers, abundant collagens and HA, on which various forces, u movements, loads and gravity, “write their history”.

Compartments of the crural fascia: clinically relevant ultrasound, anatomical and histological findings

“…However, we did not observe the presence of an aponeurosis separating the TA and EDL. Furthermore, the posterior fascia of the deep posterior muscles was thicker in the fetus than in the adult and tended to decrease in thickness, as demonstrated in a previous study [ 18 ].…”

The Effects of Aging on the Intramuscular Connective Tissue

“…We recently demonstrated that the fasciae during the fetal development are similar to “blank sheets” composed of few elastic fibers, abundant collagens and HA, on which various forces, fetal movements, loads and gravity, act to organize the tissue and the collagen fiber orientation [ 39 ]. At the same way, after birth and during life, the movements can structure the fascial system.…”

Ultrasound Imaging in Football Players with Previous Multiple Ankle Sprains: Keeping a Close Eye on Superior Ankle Retinaculum

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