Biomechanics as an Element of the Motion Clinimetry System

*Andrzej Jan Dyszkiewicz and Diana Hruby*

## **Abstract**

The study highlights the great progress in medicine, currently capable of a criterial, qualitative diagnosis of an increasing number of primary and secondary diseases in the musculoskeletal system, regardless persistent obstacles to a credible, systemic, and quantitative evaluation of the extent of existing motion dysfunctions, as well as subjective dimension of patient's suffering. It is worth to add that only parametric estimation of a qualitative dysfunction profile makes it possible to reliably monitor treatment efficiency and forecast the level of health damage after its termination. The essence of biomechanics, understood as a science describing internal and external forces' vectors, which determine specific, dynamic motion models (especially for balance and gait), has been presented in the study. Special attention has been given to anthropomotorics and psychomotorics, which give a broader context to motion's driving phenomena and consequences, thus offering a variety of new parameters that have not been considered in close relation to motion so far. While developing symmetry concept, it was pointed out that dysfunction profile comprises of sequences of parametric asymmetries registered in twin body markers.

**Keywords:** essence of biomechanics, anthropomotorics, psychomotorics, concept symmetry of body parameters, clinimetry, registers static and movement parameters

#### **1. The essence of biomechanics**

Biomechanics is an element of clinimetry, which registers movement parameters and analyzes complex inter-parameter phenomena, mainly to an extent to which they reflect the impact of internal and external mechanical forces. There are two main directions in observation, namely, retaining balance and moving body (or its parts) within Earth's gravitational field. In biomechanics, there is a slightly archaic and misleading but still bounding division for statics (applicable exclusively to the rigid bodies) and dynamics, which seems to overlook the fact that maintaining a seemingly static posture results from a conjunction of micromovements that project the center of gravity into a closed curve of critical supporting plane. A distinguishing criterion between a seemingly static and dynamic behavior of a living organism lies exclusively in technical capability to register micromovements as well as macroscopically visible movements [1]. In classic approach, dynamics can be divided into kinematics, describing movement geometry, and kinetics, describing movement's driving forces. In the state of static balance, as well as in any body's movement, the impact of certain forces can be evidenced, relying on well-known physical principles, especially vector geometry [2]. However, is the location of the center of gravity and inertia, balance, and vector calculus of marker points of the human body equal and repeatable as in the case of the description of the twin points of a rigid body, e.g., a stone sculpture or a polyester 3D print of a human body? Are there in practice differences between the physical characteristics of the behavior of marker points of rigid bodies and living organisms composed of multi-compartment, complex rigid systems with a specified number of degrees of freedom (bones and joints) and viscoelastic kinetic-buffering systems, with stiffness varying depending on the concentration and the direction of ion migration and the current pattern of reflex muscle tone stimulated by the extrapyramidal system? Is the repeatability of the vector calculus (for two bodies of identical mass) carried out after the action of force with constant parameters different for the marker point, which is part of the homogeneous structure of the rigid body, compared to the description of the marker of a multi-compartment rigid-viscoelastic system? What is the parametric drift of the viscoelastic system, the rigidity of which is interactively modified by a vector of information flowing from the inside of the body and the environment through receptors to the CNS and then by extrapyramidal pathways of the spinal cord to the muscles?

Biomechanics seeks to answer many of these questions pragmatically, by means of creating parametric sets for functions of motion markers in healthy individuals in various age groups, e.g., in the development period (evolution patterns) and in the old-age period (involution patterns) [3]. Clinical biomechanics covers sets of parametric differences in motion dysfunctions caused by a number of disease processes [4]. When applying mathematical formulas for describing rigid bodies in clinical biomechanics, it should be noted that motion is an effect of not only external and internal forces but also other internal factors, such as information vector, which is not usually directly associated with the causative aspect of motion, or else there is no relevant mathematical formula to describe it yet [5]. An important element of basic research on human motility is modeling, where body movement is treated as an effect of a control process, in which the controlled object is a simplified, mechanical model of a rigid-viscoelastic anatomical structure, and the controlling element is a regulator, which reflects the functions of sensorimotor part of the nervous system. Built in this way, a motion model is subjected to the computer simulation and later to a correlation analysis with real data acquired from sensors installed on volunteer's body, in order to modify the model. Therefore, when planning to improve biomechanical models, it is worth thinking about adding other factors to the vector analysis that may play a role in increasing the reliability and repeatability of the description of the movement of biological organisms [6]. So far, none of the existing research patterns were able to meet the strict consistency criteria in science. Every theory requires to be confirmed by experiment, and attractive, probabilistic models, which were constructed so far, operate in isolation from the actual empirical data and have moderate practical significance [7, 8].

Distinguishing anthropomotorics as a science was an attempt to find a compromise between the inductive and deductive approach in studies on human movement—it seeks to objectively examine the phenomenon of motility in all its aspects in order to provide the specialists in various fields with one uniform pattern, which would correspond with results of the real measurements. One of the most important issues in the field of anthropomotorics is an attempt to cybernetically define the characteristics of the control system (regulator) included in the model above—its functioning defines complex paths of interactions between sensors and motion effectors (muscles) and moving rigid modules (bones), connected by ties (joints) with a certain number of degrees of freedom [9–11]. Research on the complex functions of the motion regulator funded a new discipline—psychomotorics—which defines the role of senses, largely proprioceptive (tensometric strain

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*Biomechanics as an Element of the Motion Clinimetry System*

metrical test and movement metrology [15–17].

divided into:

**2. Structural and functional symmetry of the body**

gauges) and labyrinth (accelerometer-gyroscope) sensors, and the use of information obtained through them to modulate the course of movement in terms of purpose function (verified by the telereceptors) [12–14]. It is worth to remember that psychopathological phenomena, and even transient emotional states that modify one's personality profile, influence the motion control, causing visible amplitudeinterval changes, e.g., in Californian motion determinants. This is why it seems very legitimate for various authors to suggest the necessity of testing the stability of this biological regulator also in psychological aspect, by means of parallel use of psycho-

Majority of living organisms that have evolved in the gravitational field of the Earth, except for a large part of protozoa, known as non-axial, developed at least one symmetry axis and usually a symmetrical arrangement of many internal organs and body parts. The symmetry of the body is, therefore, a basic and quite specific feature of the structure, defining the distribution of its parts in relation to the adopted axis or plane. Using the symmetry criterion, the organisms can be

1.Radial symmetry organisms having a large number of symmetry planes, running through the body along a single symmetry axis. According to the number of rays, they can have either a biradial symmetry (for two radii and two planes of symmetry) or a quadriradial symmetry (the four radii and four planes of symmetry). Examples include vascular plants, sponges, polyps,

2.Organisms with bilateral symmetry, defined by the plane running along the main (long) body axis, which divides it into two parts, the right and the left. Bilateral symmetry is a construction plan both for animal (e.g., amphibians, reptiles, birds, mammals) and plant organisms (uni- and multicellular) [19].

Each of the organ pairs existing in the living organism (with bilateral symmetry), despite the high level of structural distinctiveness, functions in a substratecoupled manner with odd central organs (heart, liver) by means of mirror elements of the vascular system and information coupling with the brain via the peripheral nervous system, seeking to maintain their structural and functional symmetry. It has been proved that information and ion-molecular regulatory phenomena that penetrate from the microscopic to macroscopic scale, by maintaining functional symmetry, also tend to maintain structural symmetry that can be found in shape geometry at all levels of twin organs (e.g., limbs). These features can be described by the laws of formal logic and reflected in a model as structural-functional symmetries of parameters, not only amplitude-angle but also thermo-emissive, rheological, magnetometric, resistive, and electrometric. As mentioned above, one example can be balance in a seemingly static standing posture, which is a characteristic feature of human motor activity, defined as the body's ability to maintain body position without assistance, allowing to maintain this state during and after specific activities [20]. Balance in its essence is therefore a dynamic act of mobility, whose stability is conditioned by the efficiency of spatial neuromuscular coordination in the field of statokinetic microreflexes. Its expected result is the projection of the body's gravity center into a closed critical curve of the supporting plane, thus maintaining the standing posture. This feature is one of the external manifestations of

jellyfish, coelenterata, polychaetes, and echinoderms [18].

*DOI: http://dx.doi.org/10.5772/intechopen.92757*

*Biomechanics as an Element of the Motion Clinimetry System DOI: http://dx.doi.org/10.5772/intechopen.92757*

*Recent Advances in Biomechanics*

cord to the muscles?

and inertia, balance, and vector calculus of marker points of the human body equal and repeatable as in the case of the description of the twin points of a rigid body, e.g., a stone sculpture or a polyester 3D print of a human body? Are there in practice differences between the physical characteristics of the behavior of marker points of rigid bodies and living organisms composed of multi-compartment, complex rigid systems with a specified number of degrees of freedom (bones and joints) and viscoelastic kinetic-buffering systems, with stiffness varying depending on the concentration and the direction of ion migration and the current pattern of reflex muscle tone stimulated by the extrapyramidal system? Is the repeatability of the vector calculus (for two bodies of identical mass) carried out after the action of force with constant parameters different for the marker point, which is part of the homogeneous structure of the rigid body, compared to the description of the marker of a multi-compartment rigid-viscoelastic system? What is the parametric drift of the viscoelastic system, the rigidity of which is interactively modified by a vector of information flowing from the inside of the body and the environment through receptors to the CNS and then by extrapyramidal pathways of the spinal

Biomechanics seeks to answer many of these questions pragmatically, by means of creating parametric sets for functions of motion markers in healthy individuals in various age groups, e.g., in the development period (evolution patterns) and in the old-age period (involution patterns) [3]. Clinical biomechanics covers sets of parametric differences in motion dysfunctions caused by a number of disease processes [4]. When applying mathematical formulas for describing rigid bodies in clinical biomechanics, it should be noted that motion is an effect of not only external and internal forces but also other internal factors, such as information vector, which is not usually directly associated with the causative aspect of motion, or else there is no relevant mathematical formula to describe it yet [5]. An important element of basic research on human motility is modeling, where body movement is treated as an effect of a control process, in which the controlled object is a simplified, mechanical model of a rigid-viscoelastic anatomical structure, and the controlling element is a regulator, which reflects the functions of sensorimotor part of the nervous system. Built in this way, a motion model is subjected to the computer simulation and later to a correlation analysis with real data acquired from sensors installed on volunteer's body, in order to modify the model. Therefore, when planning to improve biomechanical models, it is worth thinking about adding other factors to the vector analysis that may play a role in increasing the reliability and repeatability of the description of the movement of biological organisms [6]. So far, none of the existing research patterns were able to meet the strict consistency criteria in science. Every theory requires to be confirmed by experiment, and attractive, probabilistic models, which were constructed so far, operate in isolation from the

actual empirical data and have moderate practical significance [7, 8].

Distinguishing anthropomotorics as a science was an attempt to find a compromise between the inductive and deductive approach in studies on human movement—it seeks to objectively examine the phenomenon of motility in all its aspects in order to provide the specialists in various fields with one uniform pattern, which would correspond with results of the real measurements. One of the most important issues in the field of anthropomotorics is an attempt to cybernetically define the characteristics of the control system (regulator) included in the model above—its functioning defines complex paths of interactions between sensors and motion effectors (muscles) and moving rigid modules (bones), connected by ties (joints) with a certain number of degrees of freedom [9–11]. Research on the complex functions of the motion regulator funded a new discipline—psychomotorics—which defines the role of senses, largely proprioceptive (tensometric strain

**48**

gauges) and labyrinth (accelerometer-gyroscope) sensors, and the use of information obtained through them to modulate the course of movement in terms of purpose function (verified by the telereceptors) [12–14]. It is worth to remember that psychopathological phenomena, and even transient emotional states that modify one's personality profile, influence the motion control, causing visible amplitudeinterval changes, e.g., in Californian motion determinants. This is why it seems very legitimate for various authors to suggest the necessity of testing the stability of this biological regulator also in psychological aspect, by means of parallel use of psychometrical test and movement metrology [15–17].
