Movement, biomechanical

The prosthesis for total knee joint replacement consists of femoral, tibial, and patellar components. Compared to the hip joint, the knee joint has a more complicated geometry and movement biomechanics, and it is not intrinsically stable. In a normal knee, the center of movement is controlled by the geometry of the ligaments. As the knee moves, the ligaments rotate on their bony attachments and the center of movement also moves. The eccentric movement of the knee helps distribute the load throughout the entire joint surface [Burstein and Wright, 1993]. 

Biomechanics is the application of mechanics to biological problems. It builds on anatomy, anthropometry and kinesiology. Kinesiology is the study of human movement. Biomechanics involves kinematics—the geometry and patterns of movement. Kinematic variables are displacement, velocity, and acceleration. Biomechanics also involves kinetics— the forces, energy, power, and work involved in movement. 

Biomechanics considers safety and health implications of mechanics, or the study of the action of forces, for the human body (its anatomical and physiological properties) in motion (at work) and at rest Mechanics, which is based on Newtonian physics, consists of two main areas statics or the study of the human body at rest or in equilibrium, and dynamics or the study of the human body in motion. Dynamics is further subdivided into two main parts, kinematics and kinetics. Kinematics is concerned with the geometry of motion, including the relationships among displacements, velocities, and accelerations in both translational and rotational movements, without regard to the forces involved. Kinetics, on the other hand, is concerned with forces that act to produce the movements. 

Winter, D. A. (1979), Biomechanics of Human Movement, John WUey Sons, New York. 

Human hearing arises from airborne waves alternating 50 to 20,000 times a second about the mean atmospheric pressure. These pressure variations induce vibrations of the tympanic membrane, movement of the middle-ear ossicles connected to it, and subsequent displacements of the fluids and tissues of the cochlea in the inner ear. Biomechanical processes in the cochlea analyze sounds to frequency-mapped vibrations along the basilar membrane, and approximately 3,500 inner hair cells modulate transmitter release and spike generation in 30,000 spiral ganghon cells whose proximal processes make up the auditory nerve. This neural activity enters the central auditory system and reflects sound patterns as temporal and spatial spike patterns. The nerve branches and synapses extensively in the cochlear nuclei, the first of the central auditory nuclei. Subsequent brainstem nuclei pass auditory information to the medial geniculate and auditory cortex (AC) of the thalamocortical system. 

Winter, D.A., Biomechanics and Motor Control of Human Movement, 2nd ed. WUey-Interscience, New York, 1990. 

Winters, J.M. and Crago, E.P. (Eds.), Biomechanics and Neural Control of Posture and Movement. Springer-Verlag, New York, 2000. 

Fioretti S. 1994. Three-dimensional in-vivo kinematic analysis of finger movement. In F. Schuind et al. (Eds.), Advances in the Biomechanics of the Hand and Wrist, pp. 363-375, New York, Plenum. 

Winter, D.A., Biomechanics and Motor Control of Human Movement, John Wiley Sons, New York, 2005. Allard, P., Stokes, I.A.F., and Blanchi, J.P., Eds., Three-Dimensional Analysis of Human Movement, Human Kinetics, Champaign, IL, 1995. 

The key limitations in the development of the discriminate functions for classification purposes, are the data-driven nature of the algorithms and the lack of theoretical orientation in the process of development and validation of these models. It is suggested that the mathematical simulation of flexion or extension trunk movement may identify an objective basis for the evaluation and assessment of trunk kinematic performance. A catalog of movement patterns that are optimal with respect to physical and biomechanical quantities may contribute to the emergence of a more theoretically based computational paradigm for the evaluation of kinematic performance of normal subjects and patients. It must be emphasized that in this paradigm one has no intention to claim that the central nervous system actually optimizes any single or composite cost function. 

Berme, N. and Cappozzo, A. 1990. Biomechanics of Human Movement Applications in Rehabilitation, Sports and Ergonomics. Worthington, Ohio, Bertec Corporation. 

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