The Fluidity of Bones
To complement the article “Fascia: The Matrix Reloaded,” in the July 2014 issue of MASSAGE Magazine.
New studies of the microstructure of bone reveals about 2 percent of bone is fluid; a citrate goo that interfaces between the collagen mesh and the nano-platelets of mineral salts.
“Surely, by now we know all about bone,” you might think. Actually, one more crack in the old model of biomechanics has just emerged in a study of bone.
We know that our skeleton is mostly calcium salts, the stiff mineral apatite we all associate with bone. We know that each individual bone is held in an envelope of collagen, with the periosteum on the outside, the endosteum on the inside, and a very leathery mesh of collagen—the same tensile fiber that makes up your tendons and ligaments—all the way through even the compact part of bone, to tie into the cartilage at either end.
The dried bone you find in the woods or the biology lab has lost all its collagen; only the mineral salts remain. But that’s only half the bone—about 75 percent, to be more exact. If you soak a bone in acid, like a chicken bone in vinegar, within a few days the salts will dissolve and leave behind a collagen mesh.
Unless your teacher did this in seventh grade, most of us have never seen this tensile network in bone. This resulting mesh is gray, very resistant to tearing, the same shape as the bone, and so malleable you can tie a knot in it.
We also know that young bones have a higher percentage of collagen mesh, while old bones have a bigger percentage of mineral salts. That is why an old bone breaks like a twig at the bottom of the pine tree, and young bones often break like a twig at the top of a pine tree, with a so-called greenstick fracture. (And we thought we knew that osteoporosis resulted when age-related fraying of the fascial mesh coincided with hormone-related loss of calcium.)
New studies of the microstructure of bone reveals about 2 percent of bone is fluid; a citrate goo that interfaces between the collagen mesh and the nano-platelets of mineral salts. This goo actually functions to hold the solid nano-platelets apart, so that they slide on each other a little. Think of the nano-platelets as a series of nickels, all close together in staggered stacks, with the liquid citrate like a thin layer of dish detergent between them.
This very similar to the liquid crystal arrangement in a tendon or fascial sheet: collagen fibers in a regular array held together with a thin layer of snotty glycoproteins. Our bodies seem to like this arrangement, as it’s resilient, and simple to build and maintain—but it’s not as we human engineers imagined.
This structure provides a much more resilient structure for bone, allowing the nano-platelets to bend and bounce a little on each other. This structure resists fracture much better than a solid bone would. In fact, osteoporotic bones do not only have less calcium, they demonstrate less citrate as well.
Fractures can propagate more easily along solid bone than they can along bone where each nano-platelet (nickel) is held apart from each other by the thin layer of fluid citrate (detergent).
The Great Designer is very smart, and we need to be careful of what we know. As they say in the South “It ain’t what you don’t know’s gonna hurt you, it’s what you do know that ain’t so.”
Thomas Myers is the author of Anatomy Trains (Elsevier 2001, 2014) and co-author of Fascial Release for Structural Balance (North Atlantic, 2010). Myers and his faculty offer continuing education worldwide, as well as professional certification in KMI Structural Integration (www.anatomytrains.com). He lives, writes and sails on the coast of Maine with his partner, Quan, and lots of animals.