Throughout the Covid Pandemic, the Master dissector of Laboratories Of Anatomical Enlightenment, Todd Garcia, has partnered with the author of Anatomy Trains, Tom Myers. The valuable collaboration has allowed live dissections to be studied over Zoom webinars, all cadavers were unembalmed and treated with the utmost respect for their gift to us. I did like to share some fascinating observations. Several patterns can also be found in nature’s geometry and dinosaurs but i will leave the latter for another article.

Small structures can lead to bigger structures.

Dorsal ventral cavity — The dorsal cavity in the rear starts big at the top and narrows down the canal. The ventral cavity is small from the mouth and throat region but keeps bigger down south.

The dorsal cavity is bigger than the ventral cavity ( mouth and nose ) at head level, progressing down the body, the same dorsal cavity becomes a small canal. In contrast, the small ventral cavity expands into a roomy one below the esophagus, towards the tail end to hold the organs.

The brachial plexus, modest as it seems, branches away from the clavicle area into further nerve trunks, divisions, cords and branches.

Tissues or structures are woven into neighboring areas by fascia and fascial lines.
As Todd tugged on the caude equina (horse tail in Latin) with his hemostat , movement could be seen in the fascial connections down to the anterior sacral foramina. The tissues in those holes (sacral foramina) were squishing back and forth with every rhythmic pull.

The same holds true with the gluteus maximus, pulling on it moves the sactrotuberous ligament inferior to the former structure.

Internally rotating the greater trochanter ( or medially rotating the leg from the hip) causes the piriformis and the obturator internus to stretch (eccentrically load). The sciatica sits inferior to the piriformis and the nerve travels down the back of the leg, interacting with the bicep femoris by fascia.

A line is ever present in the sagittal plane.
At any point down or up the body, there is a line that goes down the mid line of the body. Starting with the brain, nose septum, heart, spinal cord, vagina or urinary meatus in a male. Curiosity got the better of me and i wanted to know if the line travels further south, so looking within the Atlas Of Human Anatomy, the images do confirm this mysterious phenomena. In fact, below the penile shaft lies another line, the scrotum’s septum formed by the dartos fascia.