In this article, the author shows that "stimulation of the soft tissue in special areas on the body produces an electric current. This piezoelectrically induced current activates the healing processes in the stimulated area, and it is able to flow “towards the internal organs along the semiconductive channels of biological micromolecules”.

You can produce the electric current in these tissues, and it has enormous healing potential on the cellular, tissue and organ levels. This electric current is able to travel to the distant parts of the body, including the inner organs and normalize their function."

Below are excerpts from this well written exploration in manual therapy and piezoelectricity:

Let’s start with the basic definition. Piezoelectricity is the ability of inorganic and organic matter to generate electrical potentials in response to pure mechanical deformation without application of any external electric or magnetic field. In other words the inorganic or organic matter has inner ability to generate independent electricity in response to its simple mechanical deformation.

The phenomenon of piezoelectricity was discovered by two brothers, French physicists, named Curie, in 1880 (Williams, 1974). The authors tested the behavior of quartz crystal when mechanical force was applied to it under the different angles. If force was applied along the main axis of the quartz crystal its increase eventually crushed the specimen. However, when the authors applied force under the angle to the main axis it created the combination of the vertical mechanical compression and sheer deformation within the quartz crystal.

Such combination of two mechanical factors deformed the atomic structure of the quartz in a way that electric potentials with opposite polarities were formed and were detected on the opposite sides of the quartz crystal.

For many decades after its discovery the phenomenon of piezoelectricity was considered as a unique feature attributed solely to inorganic matter. The situation dramatically changed in the middle of the 20th century.

In 1957 two Japanese scientists, E. Fukada, MD and L. Yasuda, MD discovered the existence of the piezoelectricty in the human bone. This is a very important issue for our further discussion.

The harvested bone was placed in the holder and electrodes of amplifier were attached to the opposite surfaces of the bone to record the possible generation of electric potentials. After that the authors applied the mechanical pressure on the opposite end of the bone…. the application of pressure triggers tension (or stretch) on one side of the bone while the opposite side becomes compressed.

At the moment of the pressure application Dr. Fukada and Dr. Yasuda were able to register negative electrical potentials on the compressed side of the bone. These potentials returned to zero as soon as the further increase of pressure ceased but initial pressure was still maintained. At the moment pressure was released and the bone came back to its original form, the authors registered positive electric potentials on the tensed surface of the bone.

Why was this discovery so important? Imagine that every step you make causes constant deformation of each bone in your body and, as a result of these deformations, your bones were able to independently, from the central nervous system, generate electricity. This electric potential becomes one of the major factors in supporting the proper function of the skeletal system and as you see below in maintaining the physiological balance in the function of soft tissue and even inner organs.

Dr. Fukada and Dr. Yasuda also showed that application of the external electric current with different polarity to the bone has a completely opposite impact on its function. If a positive electric current was applied to the bone it caused its resorption (i.e., weakening), while application of the electric current with negative polarity stimulated bone growth and remodeling. This discovery became the foundation for a very effective medical treatment of delayed in fracture healing.

After the original paper was published in 1957 and scientists around the world agreed on its importance it was immediately accepted that inorganic component of the bone called apatite is responsible for the generation of the piezoelectrical potentials in the bone.

As we know bones are composed of two major parts: organic part presented by the collagen fibers and mineral part (Ca, P, etc) forms apatite.

The organic part gives the bone elasticity, while the inorganic part gives the bone its firmness and stability. Since the brothers Curie discovery piezoelectricity was attributed to the inorganic matter it was obvious for everyone that apatite was directly responsible for this phenomenon.

Everything went upside down when in 1961 two American scientists R.O. Becker, MD and C.A. Basset, MD published their paper showing that collagen fibers or the organic part of the bone is directly responsible for piezoelectrical potentials generated by the bone. This study sent shock waves through the world’s medical community because if the collagen fibers in the bone were able to generate electric potentials the collagen fibers in other tissue and organs are able to do exactly the same. As we know the collagen is a major framework material for the organs and soft tissue and it is everywhere in our body.

After Dr. Becker and Dr. Basset original publication the scientists rushed to examine the possibility of piezoelectricity in other tissue. The results were astonishing. It was found that elasine in the skin (Shamos, Lavine, 1967), collagen in tendons (Anderson and Eriksson, 1968), collagen in ligaments (Fukada, Hara, 1969), actine and myosin in skeletal muscles (Fukada, Ueda, 1970), and even some individual amino acids (Vasilesku, 1970) an DNA molecules (Fukada, 1982) exhibited piezoelectrical properties. All of this allowed Dr. M.H. Lavine to conclude that “piezoelectricity is a property of most, if not all, tissue in the plant and animal kingdoms”.

Each collagen molecule is a strong dipole, i.e. it has two oppositely charged ends (see Diagram 5). The head is bigger part and it has a slightly larger positive charge while the tail is smaller and it has a slightly smaller negative charge. Thus overall charge of each collagen molecule is positive.

Diagram 5. Electrophysiological model of collagen fiberDiagram 5 - Electrophysiological model of collagen fiber

Collagen molecules unite together to form different anatomical structures (tendons, ligaments, bones, structural frame of the inner organs, etc.). All collagen molecules in combination with other electrically active proteins generate a, so called, fixed electric charge of each organ and tissue.

Thus, the fixed electric charge is a cumulative charge of all electrically active molecules in the area. Even under normal conditions this charge constantly changes as a result of the individual person’s physical activity, diet, level of stress, etc. Despite of these constant fluctuations, changes in the fixed electric charge stay within the physiological range assigned to this particular tissue.

The situation changes dramatically if the soft tissue or inner organ were traumatized, or has developed inflammation, etc. The fixed electric charge within the affected area immediately changes its normal value as a result of the pathological process.

As we now know any inflammation or trauma of the soft tissue increases the positive fixed electric charge and the collagen fibers are one of the major contributors to this process . Swelling, rupture and twisting of the normal collagen fibers greatly contribute to the increase of the positive fixed charge in the soft tissue. The healing process after initial trauma or inflammation is always accompanied by slow restoration of the fixed electric charge in the affected area.

During the manual therapy, external mechanical stimuli in form of repeated application of strokes deform the collagen molecules and generate the piezoelectricity which increases the negative fixed electric charge. As we discussed above, the negative electric charge has the greatest impact on the proliferation, growth and regeneration of the tissue.

Also, the increase of the negative charge in the affected area is the critical factor in the correct alignment of the pro-collagen fibers before their maturation into the fully developed collagen fibers. The delay of this process slows the local healing. Thus the restoration of the fixed electric charge is a critically important process in reducing the tension in the soft tissue and eliminating the physical and even mental stress. At the same time it is an equally important component in speeding up the healing process.

Modern technology allowed scientists to measure the piezoelectrical properties even within a single collagen fiber. In the recent study Minary-Jolandan and Yu, (2009) showed that single collagen fiber is able to generate piezoelectric coefficient of 1 pm V(-1) and summation of piezoelectrical charges generated by each collagen fiber allow the entire tendon to generate electric potential up to tens of millivolts, depending upon the size of the tendon. The authors of this study strongly reinforced the previously mentioned publication of Shamos and Lavine who found that only shear deformation of the collagen fibers triggers the piezoelectrical effect. Thus the angle of the application of the pressure (45 degrees are the most preferable) is a critical factor in the generation of the piezoelectricity and normalization of the electrophysiological properties of the soft tissue.

A very important article was published in 1977 by one of the most respected scientific authorities in the field of bioelectricity, Professor B. Lipinski, MD. Using his experimental data he formulated the theory which links the therapeutic effect of soft tissue manipulations, acupuncture, Hatha Yoga and the action of negatively charged air ions with piezoelectrical properties of the biological tissue.

According to this theory, proteins, mucopolysaccahrides, nucleic acids, etc. which compose all tissue of our body are able to generate piezoelectricity. Thus, these substances have the ability to transfer the externally applied mechanical energy (e.g. by manual therapy) into electric energy inside the soft tissue.

The author showed that stimulation of the soft tissue in the special areas on the body produces the electric current. This piezoelectrically induced current activates the healing processes in the stimulated area, and it is able to flow “towards the internal organs along the semiconductive channels of biological micromolecules”. You actively produce the electric current in these tissues, and it has enormous healing potential on the cellular, tissue and organ levels. This electric current is able to travel to the distant parts of the body, including the inner organs and normalize their function.