Chuck’s Articles

The Viability of the Interstitial Space

The design and action for the absorption of fuel & oxygen and the elimination of waste, through the interstitial space, lends itself to most if not all of the problematic health conditions in the human body.
First, a challenge to the accepted definitions of the vascularity of tissues. All anatomy & physiology texts consider epithelial tissue and cartilage avascular, and muscle, nerve and the rest of the connective tissues, vascular. This is very misleading in terms of fuel & oxygen delivery and waste removal. All fuel & oxygen is delivered to the body’s tissues from the arterial side of the capillary beds. Most cellular waste is removed through the venous side of the capillary beds and the lymphatic vessels. Therefore, the movement of fuel & oxygen to the cells and the movement of waste to the veins and lymphatic vessels must happen through the interstitial space. No capillary beds go inside cells, whether they are muscle, nerve, epithelial, or connective tissue cells. They are not truly vascular: they rely on diffusion of fuel, oxygen, and waste through the interstitial space. The only truly vascular tissue in the human body would be the ground substance, the base fluid of the interstitial fluid, of connective tissue.

The design problem arises from the nature of cellular absorption and waste production. Simply, all cells absorb nutrients and oxygen directly through the cell wall. The cells use the fuel & oxygen for their cell processes and produce waste, which is expelled through the cell wall. Thus, fuel, oxygen, and waste are exchanged through the same space, the interstitial space. The movement of fuel & oxygen to the cells and the movement of waste to the veins and lymphatic vessels is a key to health – the viability of the interstitial space.

The other component of waste to be removed through the veins and lymphatic vessels are dead cells. Like cellular waste, dead cells must move through the interstitial space to be eliminated from the body.

In this context, the conditions, the viability, of the interstitial space and interstitial fluid is of paramount importance to the health of the body’s tissues. If the interstitial space is maintained as it was designed all will be well. If the viability of the interstitial space is compromised, then cellular function and health will be compromised also due to the ‘stagnation’ of toxins.

Note that the skeletal muscles of the body are the primary resource for returning fluids from the interstitial spaces to and through the veins and lymphatic vessels. When skeletal muscles contract the interstitial space is squeezed and its volume reduced. The waste products of the cells are forced into the venous side of the capillary beds and the lymphatic vessels. When the muscles relax, the area of the interstitial space increases and it is filled with fuel & oxygen-rich blood drawn from the arterial side of the capillary beds. There are many forces at work here from osmotic pressure to action of the smooth muscle of arteries and veins, but the action to the skeletal muscle is by far the largest single factor. Consider the skeletal muscles as the ‘return heart’, as well as the main pump for movement of fluids in the interstitial space.

Disease is nothing else but an attempt on the part of the body to rid itself of morbific matter
- Dr. Thomas Sydemham (the English Hippocrates)

The main components of ‘morbific matter‘ in the body on a daily basis is cellular waste and dead cells. Dr. Sydenham was a 15th century physician of considerable reputation, and his observation is still highly noted and not refuted.

If Dr. Sydenham’s hypothesis is true, then anything that interferes with the migration of waste product from the cells‘ walls to the veins and lymphatic vessels is a main contributor to disease.

The hypothesis here is that nothing compromises the viability of the interstitial space more than chronic hypertonicity. Certainly, diet and activity are important factors, but the reduction of volume resulting from hypertonicity has the most problematic impact.

Examination of the dynamics of skeletal muscle tonicity on the volume of the interstitial space

The ligaments surrounding joints and the joint capsules are not designed to support and stabilize joints alone. They are designed to do it with muscle tone (see Job’s Body by Deane Juhan, chapter 3 “Connective Tissue”).

To begin, we will define ideal skeletal muscle tonicity as the tone it takes to support the joints and circulate the fluids of the body both statically ‘resting muscle tone’ (no significant body exertion – e.g., lying down ) , and dynamically ‘active muscle tone’ (the body is moving – e.g.,walking), and no more. Any muscle tone in addition to the tone necessary to support the joints and circulate the fluids would be defined as hypertonicity. Now, let’s compare the quality of the interstitial space under ideal as opposed to hypertonic conditions.
  Picture the interstitial space between the muscle fibers of any skeletal muscle. Imagine the space as greatly magnified, so that the space between adjacent muscle fibers is 4 inches when the muscle is at ideal resting muscle tone. (Remember that no two muscle fibers ever touch each other, nor any cells; all cells are always surrounded by interstitial space and fluid, regardless of the circumstances. Even epithelial cells have an exudate around them.) Now this interstitial space is a very busy place. There is a lot of stuff in here and a lot of action is going on. There are neurons coursing through, free nerve endings, capillary beds, lymphatic vessels, all sorts of antibodies, platelets, fibroblasts, collagen fibers, and all of them moving through interstitial fluid whose base is the ground substance of connective tissue proper.

When this muscle area we are imagining fully contracts the space between the adjacent muscle fibers reduces to, let’s say, 1 inch. The fluid that occupied the space is forced into the veins and lymphatic vessels, and most of it is waste product. When the muscle relaxes and returns to ideal resting tone, the space expands back to 4 inches, the space being filled with fresh blood plasma drawn from the arterial capillary bed. Under these circumstances, circulation is completely adequate to avoid the accumulation of “morbific matter” and the propagation of the disease process is avoided. The interstitial space and the exchange of fuel, oxygen and waste are functioning as they were designed to.

If there is hypertonicity in the muscle, when the muscle relaxes it will not open the space to our hypothetical 4 inches – the space will be less. When the muscle relaxes, the space will be less. The full pumping action is reduced and compromised.

The theme here is that chronic hyper-tonicity of skeletal muscles is by far the number one condition that stagnates waste product (“morbific matter”) in the interstitial space.

There are several factors at the center of the reduced ability of the body to rid itself of waste product from the interstitial space. They are:

• reduced volume of the interstitial space at resting and active muscle tone
• increased energy demand of hyper-toned muscle
• increased waste production of hyper-toned muscle
• pressure or ‘squeezing’ of the capillary beds and the vessels leading to and from them (arteries and veins)
• pressure or ‘squeezing’ of the lymphatic vessels
• increased amount of collagen fibers in the interstitial space due to increased pressure on local fibroblasts
• tendency toward less overall movement thickening ground substance
• tendency toward more hyper-tonicity due to pain-spasm-pain cycle

All of these factors combined increase the demand for fuel & oxygen, increase waste production, and decrease the ability to remove waste.

The volume of the interstitial space at resting muscle tone is reduced due to the fact that with chronic hyper-tonicity, the muscle does not operate at ideal resting and active tone; rather it has acquired a higher tone that has now become ‘normal’. This new normal tone takes up more space than would ideal tone. In the magnified picture of the muscle we were imagining, the interstitial space would not be 4 inches and 1 inch, it would be less. How much less would depend on the level of hyper-tonicity, but the volume of the interstitial space would certainly be compromised.

The energy requirements of a hyper-toned muscle would be higher than of a muscle of ideal tone, simply because it is working harder and therefore requires more fuel. In the same sense, the hyper-toned muscle creates more waste product than the ideal-toned muscle, again because it is working harder.

The supply and return plumbing for the circulatory system are also compromised. Note that the arteries, similar to nerves, run deep in the tissues and then migrate superficially as required. The arteries divide into arterioles and finally capillary beds (half the bed, the supply side – the venous side is the other half), course through fascial planes and into the interstitial space surrounding cells. Hyper-toned muscle will squeeze the arteriole side of the circulatory system, reducing the area of the lumen of the vessels, raising pressure in the system (higher blood pressure) and not helping supply.

The problems raised on the return side, the venous and the lymphatic vessels, are far more problematic and insidious to the interstitial space In terms of other diseases. Squeezing the return side does not increase pressure on the fluid inside, it directly reduces it. The pressure of any skeletal hyper-toned muscles will compromise flow through the return system (veins and lymphatic vessels) compared to the functional design of the system, which looks in all aspects to be based around ideal muscle tone.

The biggest impact, though, seems to happen at the interstitial space level. The compromised volume of the interstitial space, the heightened pressure, the thicker collagen net, and the gelled ground substance all reduce the effectiveness of circulation. This is where toxins build up, and they build up because these factors impede the toxins’ flow from the cells to the veins & lymphatic vessels. According to Dr. Sydemham, the restriction of cellular waste and dead cells in the interstitial space is the root cause of all disease.

Massage as the Best Solution

Massage may very well be the best of numerous solutions for the circulation dilemma, mainly because it can address the situation directly from a number of perspectives.

First perspective is the mechanical view of squeezing the tissue and releasing it. Like wringing a sponge, squeezing, pressing, twisting, and releasing the myo-fascial structures moves fluids through the interstitial medium. The effectiveness of the massage technique would be a function of feeling the quality of resilience/resistance in the soft tissue and working the resilience into the resistance, something talented massage therapists are excellent at. This will move toxins (cellular waste and dead cells) out of the interstitial space and into the veins and lymphatics, to be filtered by the kidneys.

From a neural view, the free nerve endings/chemoreceptors are situated in the interstitial space. Being chemoreceptors, they sense the local chemistry. If they are in a solution (the interstitial fluid) dominated by toxins they will send that information to the central nervous system. Unfortunately, this does not elicit a relaxation parasympathetic response to help flush the interstitial space, but seems to trigger a protective response (sympathetic) in the form of more muscle tone. Conversely, flushing toxins out with effective massage work surrounds the chemoreceptors with fresh fuel & oxygen. The reflex response to this is definitely parasympathetic relaxation of resting muscle tone.

Systemically, aiding veinous and lymphatic drainage by working toward the heart as a finishing stroke makes more room for the movement of cellular waste and dead cell removal.

It is interesting that some of medical research’s original basic findings supports effective bodywork as a logically effective disease preventative. Physiology suggests that compromised circulation is at the root of all disease.  The interstitial space is the central feature of circulation, and the removal of waste and toxins are the key feature to its viability.