Petr Kubovy

Forensic Biomechanical Analysis of Falls from Height Using Numerical Human Body Models

Abstract:  This article describes the method of using human body models developed originally for the use in automotive safety in forensic reconstructions of falls from height. The MADYMO® software package and multibody human body models were used in forensic analyses of two real cases—a fatal fall from a window c. 13.8 m above the ground and a fall into a c. 2.5‐m deep cellar pit resulting in isolated ankle joint injury. The performed series of numerical simulations helped to reconstruct the events and to resolve legally relevant questions concerning various aspects of the falls. The benefits as well as limitations and potential biases associated with the use of numerical simulation in forensic biomechanical settings are discussed. The method has proven to be effective under specific circumstances, though the cost (both financial and temporal) still prevents it from wider use.

Biomechanical factors influencing the beginning and development of osteoarthritis in the hip joint

SummaryOsteoarthritis (OA) can be used as a common name for a group of overlapping pathological conditions when the balance between the processes of degradation and synthesis, in individual parts of the cartilage, is disturbed and leads to gradual cartilage destruction. A preventive approach toward OA helps with a timely diagnosis and subsequent treatment of this disease. One of the significant risk factors affecting development of hip joint OA is the mechanism and magnitude of mechanical loading on the joint. The main motivation for this work was to verify the hypothesis involving a pathologic cycle (overloading – change of locomotion – overloading) as contributory to the development of OA and whether it can be stopped, or at least partly decelerated, by a suitable change of movement stereotypes. Providing that there is a natural balance of muscular action, from the beginning of OA, the development of OA can be significantly decelerated. The return to a natural force balance can be achieved using suitable exercise and strengthening of muscular structures. In order to verify the hypothesis, we undertook experimental measurements of gait kinematics and a computational analysis of the hip joint using the Finite Element Method.

THE CHANGES OF THE RHEOLOGICAL PROPERTIES OF THE KNEE JOINT IN THE SEPARATE CAUSES

relaxation. The rate of the velocity (maximum 0,15 rad.s -1 ) is limited from top with the capability of the sarcomare to relax and from below with the capability of the patients to keep the concentration. All the movement is realized in the horizontal plane (patient lies on the side) for the elimination the gravitation effect on the torque. The shapes of the curves and its changes are evaluated by various objectification parameters in the dependency of its character and its potential physiological reasons: From the energy point of view it is the quantity of the dissipation energy and total movement efficiency, the end points values (quasistatic parameters) contains only the elastic components of forces and geometrical parameters like a local maximums, slopes, position in the coordinated system and curve correlations. The experiments are composed like a pilot study with the limited number of members, men and women between 20 and 25 years old (10 with the physical stress of knees, 10 with the hypothermia of the knees, 24 without stress and 2 with the rupture of the ACL).

The Influence of Woman’s Mastectomy on Breathing Kinematics

The aim of this study is to objectively determine the effect of total mastectomy on the extent of breathing movements of the thoracic and abdominal wall in the women (n = 6) who underwent this operation, compared to the breath movements of healthy women. Another aim is to find out whether there has been a symmetrical disturbance of the extent of movement between the operated and unoperated side of the chest and abdomen during breathing.

Does mechanical loading influence development of osteoarthritis in hip joint

Osteoarthritis (OA) can be used as a common name for a group of overlapping pathological conditions when the balance between the processes of degradation and synthesis, in individual parts of the c...