The treatment of connective tissue and particularly of the extracellular matrix opens up new ways to understand the pathogenesis of diseases. The fundamental substance has been downplayed since the beginning of histology, firstly by considering it with a light microscope as an amorphous and inert substance and, later, by altering its pH and dewatering it with staining methods.In most routine preparations the fundamental substance has been lost because it has been removed during fixation and dehydration of the tissue. However, the fundamental substance is without a doubt one of the components of the human body that can present new perspectives in medical treatments.The behavior of the fundamental substance is defined as a non-Newtonian fluid. It is a colloid whose properties explain the mechanism of the extracellular matrix. When a particle moves in a liquid that is at rest or in motion, and this liquid exerts pressure and stress on the surface of the particle, the hydrodynamic comes into action.Any technique applied to the human body interacts with the extracellular matrix in the same way as at cellular level. The ubiquity of the fundamental substance will affect all expressions of disease.The development of the aponeurologic surgery allows you to identify—in a non-aggressive technique—changes in the extracellular matrix in a complete way, integrating the entire body as a fluid in a closed container. Aponeurologic surgery corrects imbalances in the extracellular matrix due to non-Newtonian fluid behavior of the fundamental substance. Regeneration capacity depends on the integrity of the extracellular matrix.