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Cover -- Table of Contents -- Introduction -- CHAPTER 1 Biomechanics of Occupant Responses During Recreational Off-Highway Vehicle (ROV) Riding and 90-Degree Tip-Overs -- Introduction -- Methods-Passive Response -- Methods-Active Response -- Surrogates -- Instrumentation -- Off-Road Course -- Roll Spit -- Common Physical Activities -- Data Analysis -- Results and Discussion -- Passive Response -- Active Response -- 90-Degree Rolls and Common Physical Activities -- Conclusions -- References -- Acknowledgments -- CHAPTER 2 Comparative Study of Road Accidents in Iceland and Side Impact Compatibility -- Introduction -- Road Accidents in Iceland -- Fatal Side Impact Accidents -- Finite Element Model -- Verification and Sensitivity of the Parameters -- The Influence of Variation of HOF in Side Impacts -- The Effect of HOF on Compatibility in Side Impacts -- Conclusion -- Acknowledgments -- References -- CHAPTER 3 Development of Numerical Models for Injury Biomechanics Research: A Review of 50 Years of Publications in the Stapp Car Crash Conference -- Introduction -- Head Models -- Lumped-Mass Models -- Finite Element Models -- Application of Models -- Pediatric Brain Models -- Other Head Component Models -- Animal Head Models -- Head Model Discussion -- Simulating the Skull and Brain Junction -- Skull Thickness -- Injury Measures -- Material Properties and Experimentally Measured Brain Responses -- Neck Models -- Two-Joint Neck Models -- Multibody (MB) Neck Models -- FE Neck Models -- Model Geometry -- Material Properties -- Muscle Simulation -- Model Validation and Application -- Thoracic Models -- Abdominal Models -- Geometry -- Material Properties -- Model Application and Validation -- Upper Extremities -- Geometry -- Material Properties -- Application and Validation -- Lower Extremity Models the Pelvis -- Geometry -- Material Properties.

An appealing and engaging introduction to Continuum Mechanics in Biosciences This book presents the elements of Continuum Mechanics to people interested in applications to biological systems. It is divided into two parts, the first of which introduces the basic concepts within a strictly one-dimensional spatial context. This policy has been adopted so as to allow the newcomer to Continuum Mechanics to appreciate how the theory can be applied to important issues in Biomechanics from the very beginning. These include mechanical and thermodynamical balance, materials with fading memory and chemically reacting mixtures. In the second part of the book, the fully fledged three-dimensional theory is presented and applied to hyperelasticity of soft tissue, and to theories of remodeling, aging and growth. The book closes with a chapter devoted to Finite Element analysis. These and other topics are illustrated with case studies motivated by biomedical applications, such as vibration of air in the air canal, hyperthermia treatment of tumours, striated muscle memory, biphasic model of cartilage and adaptive elasticity of bone. The book offers a challenging and appealing introduction to Continuum Mechanics for students and researchers of biomechanics, and other engineering and scientific disciplines. Key features: -Explains continuum mechanics using examples from biomechanics for a uniquely accessible introduction to the topic -Moves from foundation topics, such as kinematics and balance laws, to more advanced areas such as theories of growth and the finite element method.-Transition from a one-dimensional approach to the general theory gives the book broad coverage, providing a clear introduction for beginners new to the topic, as well as an excellent foundation for those considering moving to more advanced application.

This paper describes some of the folk norms or so-called "rules of thumb" that governed the making of tools and implements up to middle of the nineteenth century. These norms were established on the bases of intuition or through a long process of development by trial and error. In many instances dimensions arrived at on the basis of these norms have agreed with those established as optimal by means of biomechanical analysis.

Introduction:The modern long cane has been used by people who are blind for traveling for decades. This article describes parameters surrounding the collection of over 10,000 trials of people walking with the long cane to detect drop-offs or obstacles.Methods:The data include 10,069 trials representing 101 different participants in 366 conditions over 11 studies spanning the 9 years from 2007 to 2016. Each of the studies investigated different participant or cane characteristics or both in terms of their effect on either drop-off or obstacle detection. Results of detection performance in these studies appear in other articles. This article describes biomechanical measures derived from 3-D motion analysis equipment used during the studies.Results:Initial treatment of the large data set indicated that participants tended to not center their cane arc laterally on their body, deviating up to about 20 centimeters from midline. Arc widths averaged almost a meter, and arcs were generally centered. Participants were generally poor at being in step or having consistent rhythm. Coverage rates averaged about 85%.Discussion:Although participants might have demonstrated artificially high skill performance due to being in a research study, data do offer insights into mechanical performance of skills. This survey of the data set indicates that not centering the hand holding the cane does not decrease body coverage less than about 85%. However, further analyses will be conducted to delve more deeply into all aspects of the data.Implications for practitioners:Basic cane skills can be taught with short sessions and massed practice. Novices can acquire basic cane skills on par with cane users who are blind, but individual differences exist and the interplay of biomechanical variables needs to more fully understood.

International audience ; This special issue follows the Euromech534 colloquium which was organized in Saint-Etienne (France) from 29th to 31st May 2012 on the topic "Advanced Experimental Approaches and Inverse Problems in Tissue Biomechanics". The objective of the colloquium was to foster the interaction and networking of those working in the general area of mechanics applied to biological tissues, materials and applications, throughout universities, industries, and government laboratories.

The last ten years have seen explosive growth in the technology available to the collision analyst, changing the way reconstruction is practiced in fundamental ways. The greatest technological advances for the crash reconstruction community have come in the realms of photogrammetry and digital media analysis. The widespread use of scanning technology has facilitated the implementation of powerful new tools to digitize forensic data, create 3D models and visualize and analyze crash vehicles and environments. The introduction of unmanned aerial systems and standardization of crash data recorders to the crash reconstruction community have enhanced the ability of a crash analyst to visualize and model the components of a crash reconstruction. Because of the technological changes occurring in the industry, many SAE papers have been written to address the validation and use of new tools for collision reconstruction. Collision Reconstruction Methodologies Volumes 1-12 bring together seminal SAE technical papers surrounding advancements in the crash reconstruction field. Topics featured in the series include: • Night Vision Study and Photogrammetry • Vehicle Event Data Recorders • Motorcycle, Heavy Vehicle, Bicycle and Pedestrian Accident Reconstruction The goal is to provide the latest technologies and methodologies being introduced into collision reconstruction - appealing to crash analysts, consultants and safety engineers alike.

For dynamic simulation of human movement, segment axis systems are often defined by the inertial tensor unique to each simulated body segment. When empirical three-dimensional data are sought that describe either the mass distribution or the kinematic properties of the human body, anatomical frames of reference are needed for the sake of measurement methodology and data comparability. Anatomical axis systems are based on anatomical landmarks that must represent functional and stable features in the skeletal geometry. The role of anthropometric landmarks used in defining anatomical coordinate axis systems is discussed with examples from current research regarding the kinematics of the hip joint and mass distribution of the whole body. The use of anatomical frames of reference will improve the correspondence between computer simulations of the human body and the biological structure.

European Union, QREN-InAlentejo-Programa Operacional do Alentejo, 2007–2013/National Strategic Reference Framework, project title Parque de Ciência e Tecnologia do Alentejo, Laboratório de Investigação em Desporto e Saúde/Alentejo's Science and Technology Park, Sport and Health Research Center, Instituto Politécnico de Santarém, Escola Superior de Desporto de Rio Maior/Escola Superior de Saúde de Santarém/Polytechnic Institute of Santarém, and Sport Sciences School of Rio Maior/Health School of Santarém. Project coordinator is Rita Santos-Rocha (Project reference: ALENT-07-0262-FEDER-001883) ; During pregnancy women experience several changes in the body's physiology, morphology, and hormonal system. These changes may affect the balance and body stability and can cause discomfort and pain. The adaptations of the musculoskeletal system due to morphological changes during pregnancy are not fully understood. Few studies clarify the biomechanical changes of gait that occur during pregnancy and in postpartum period.Purposes. The purpose of this review was to analyze the available evidence on the biomechanical adaptations of gait that occur throughout pregnancy and in postpartum period, specifically with regard to the temporal, spatial, kinematic, and kinetic parameters of gait.Methods. Three databases were searched and 9 studies with a follow-up design were retrieved for analysis.Results. Most studies performed temporal, spatial, and kinematic analysis. Only three studies performed kinetic analysis.Conclusion. The adaptation strategies to the anatomical and physiological changes throughout pregnancy are still unclear, particularly in a longitudinal perspective and regarding kinetic parameters.

INTRODUCTION: Stress fractures are a common injury in athletes in general, and runners in particular. Stress fractures are a chronic, or overuse, injury resulting from fatigue damage to the bone. They occur when the damage accumulated due to the repeated application of physiological loads exceeds the capacity of the bony tissue to repair itself. The incidence of stress fractures in athletic populations is up to 50% (Brukner et al., 1996). Tibial stress fractures in particular are very common in recreational and competitive runners and military recruits. The tibia is the most common site of stress fracture in distance runners, accounting over 40% of all stress fractures (Brukner et al., 1996). The typical recovery time from a stress fracture is between 6 and 12 weeks. This includes periods of rest and reduced activity, to allow the natural reparative process of bone to take place at a rate exceeding that of damage accumulation. Reduced training capacity for a period of two to three months is a significant amount of time for both runners and military recruits. Therefore, identification of injury mechanisms and the prevention of stress fractures in runners is an important area of study. RISK FACTORS: Many risk factors for stress fracture have been proposed. Some of these factors are intrinsic to the individual athlete; some are extrinsic and related to environmental factors. Many risk factors can be modified, whereas others can only be accommodated. Proposed extrinsic factors include those related to training, including the volume per session and per week, intensity level, running surface, and recent changes in the program (Bennell & Brukner, 2005). These factors can be modified, although other considerations such as competition scheduling or basic training requirements may influence this. Proposed intrinsic factors include anatomical structure of the lower extremity, muscle strength, flexibility, menstrual status, bone density, diet and nutrition, and running biomechanics (Bennell & Brukner, 2005). In order to investigate contributions to stress fracture risk from biomechanical factors, other risk factors should be standardized as much as possible between comparison groups. GAIT BIOMECHANICS: A series of investigations into the biomechanics of running in relation to tibial stress fracture have been conducted. The aim of these studies was to determine objectively whether running biomechanics are different in those who have sustained a tibial stress fracture compared to those with no previous lower extremity bony injuries. This may enable identification of those at increased biomechanical risk of tibial stress fracture and of potential strategies to reduce their risk by modification of these factors. In cross-sectional studies the influence of potential confounding factors can be reduced by matching characteristics of the participants across comparison groups. Factors including age, height, weight, sex, footstrike pattern, and monthly running mileage can be matched to reduce the variability between groups due to these potentially confounding factors. Given that tibial stress fracture is an overuse injury due to fatigue of bone tissue, early work in this area focused on loading characteristics of gait, primarily ground reaction forces. Studies focusing on peak ground reaction forces were inconclusive, with some indicating greater peak values after tibial stress fracture compared to controls (Grimston et al., 1991) and others finding no difference (Crossley et al., 1999; Bennell et al., 2004). However, greater loading rates were found in runners with a previous tibial stress fracture compared to matched control runners (average vertical loading rate 79.0BW/s vs. 66.3BW/s, P = 0.041; instantaneous loading rate 92.6BW/s vs. 79.6BW/s, P = 0.036; Milner et al., 2006a). Additionally, a more direct measurement of tibial loading, tibial shock (peak acceleration) measured using an accelerometer, also supported the hypothesis of increased loading of the tibia in those susceptible to tibial stress fracture compared to controls (7.7g vs. 5.8g, P = 0.014). However, further analysis indicated that tibial shock explained only 17% of the variance between tibial stress fracture and control groups. This finding supported the hypothesis that the risk of tibial stress fracture is multifactoral, and that other biomechanical factors are likely involved. FREE MOMENT: During running, the tibia is exposed simultaneously to a combination of shearing, bending and torsional loads, in addition to compression (Ekenman et al., 1998). While vertical ground reaction forces and tibial shock may provide an indication of the compressive load applied to the tibia, they do not indicate torque about the vertical axis. The free moment of ground reaction force indicates this torque at the point of contact of the runner with the ground (Milner et al., 2006b). Thus, it may provide an indirect measure of the torque acting on the tibia. Comparison of the magnitude of peak free moment during the stance phase of running between those with previous tibial stress fracture and matched controls indicated greater values in the stress fracture group (9.3 x 10-3 vs. 5.9 x 10-3Nm/BW*ht, P < 0.001). Further analysis suggested that this variable explained 27% of the variance between the two groups. It's important to note that the majority of runners exhibit an adduction bias in the direction of free moment during the stance phase of running (i.e. resisting toe out torque of the foot on the ground). This torque has been associated with pronation (eversion) in the literature (Holden and Cavanagh, 1991). These loading-related variables that exhibit differences during running between runners with a previous tibial stress fracture and matched controls occur in the earlier part of stance phase. During early stance, body weight is shifted rapidly onto the stance limb. Therefore, studying lower extremity biomechanics during this period of rapidly increasing loading may be critical in understanding differences between runners susceptible to tibial stress fracture and healthy controls. INITIAL LOADING: Higher vertical ground reaction force loading rates and higher tibial shock have been found in runners with previous tibial stress fracture compared to matched controls. The effect of external loading on the body can be modulated by body's the response to it. A good example is jumping off a wall onto the ground: landing in a stiff posture with knees maintained in extension results in higher loads transmitted through the body than landing with a large range of flexion motion at the lower extremity joints. In this respect, the knee is often considered to be of primary importance as a damper during landing. During running, each stance phase can be considered a single-legged landing, since the runner moves from a flight phase to single limb support. Thus, the initial loading part of the stance phase, from foot contact to the impact peak of vertical ground reaction force, may be important in terms of factors relating to tibial stress fracture. Vertical loading rate, which is calculated over the initial loading period, is greater in runners with a previous tibial stress fracture compared to controls (Milner et al., 2006a). Therefore, the body's response, in particular at the knee, to the high rate of loading during early stance may be an important consideration in injury risk. Knee joint stiffness was indeed found to be greater in runners with previous tibial stress fracture compared to controls (0.044Nm/(mass*ht) vs. 0.030 Nm/(mass*ht), P = 0.015; Milner et al., 2007). It was also positively correlated with tibial shock. However, there was only a moderate relationship in the stress fracture group between knee stiffness and tibial shock (r = 0.406). In the control group, the relationship was weak (r = 0.161). Thus, the body's response to loading during the early part of stance phase may also be important in understanding the complex relationship between loading and the occurrence of tibial stress fracture. PROXIMAL AND DISTAL FACTORS: While several studies have focused on ground reaction forces and tibial shock measures in relation to tibial stress fracture, it should be remembered that the lower extremity is a linked chain with several joints and segments. The position of each lower extremity joint is important in determining the position of each segment. While static alignment factors in general have not shown strong association with tibial stress fracture, there is some evidence that extremes of foot type (very high or very low arches) may increase the risk of tibial stress injuries (Barnes et al., 2008). It has been suggested that dynamic alignment during the stance phase of running may be important in relation to stress fracture (Bennell & Brukner, 2005). Abnormal joint kinematics within the lower extremity chain may contribute to abnormal distribution of musculoskeletal loads, including within the tibia. Both proximal and distal joint kinematics may contribute to the combination of factors predisposing some runners to tibial stress fracture, even in the presence of normal loads. Altered frontal and transverse plane joint positions may change the axial, bending and torsional loads in the tibia. Several important differences were found in a comparison of frontal and transverse plane kinematics at the hip, knee, and ankle in female runners (Milner et al., in review). In particular, peak rearfoot eversion (11.7° vs. 9.0°, P = 0.015) and peak hip adduction (11.6° vs. 8.1°, P = 0.004) were both several degrees greater in runners with previous tibial stress fracture compared to controls with no previous bony injuries.This ties in with other work that found peak hip adduction, peak rearfoot eversion and the absolute free moment were the most important predictors of previous tibial stress fracture in distance runners (Pohl et al., 2008). Currently, it cannot be determined whether the differences in the frontal plane at the hip are a proximal compensation for the distal differences in the frontal plane at the rearfoot or vice versa. DISCUSSION: While many factors, both internal and external to the runner, likely play a role in the development of tibial stress fractures, several biomechanical variables have been associated with this injury. It should be noted that the studies reported were retrospective and cross-sectional in design. Therefore, it cannot be determined whether the biomechanics of runners with a previous stress fracture measured after recovery from the injury are the same as prior to the stress fracture. While this is a limitation in relation to predisposing factors for tibial stress fracture, a large proportion of runners suffer multiple stress fractures after the initial occurrence. Thus, the information obtained in these studies is directly applicable to the case of recurring stress fractures. Future prospective studies may be able to confirm whether the high risk biomechanical features of running were also present in runners with tibial stress fracture prior to their injury. Primarily, several loading-related variables and joint angles have been identified and found to be greater in runners with a previous tibial stress fracture compared to runners with no previous bony injury. In terms of loading, the literature is somewhat inconclusive with regard to ground reaction force variables. While it seems intuitive that bony injury and fatigue fracture (i.e. stress fracture) are associated with damaging loads that exceed the body's ability to repair itself, tibial loading is only indirectly linked to ground reaction force variables. However, it appears that vertical loading rates (Milner et al., 2006a) and the absolute free moment (Milner et al., 2006b) may be increased in runners with previous tibial stress fracture. These variables may be providing an indication of the magnitude of compression and torsional loads that the tibia is subjected to during the stance phase of running. Given the lower magnitudes of these variables in healthy runners compared to those with a previous stress fracture, these aspects of running biomechanics may be modifiable. Decreasing their magnitude may decrease the risk of injury in susceptible runners. Similarly, the kinematic differences observed and abnormal peak angles reported at the hip and rearfoot in runners with previous tibial stress fracture (Milner et al., in review) may also be modifiable. Although a detailed consideration of interventions to modify running biomechanics is beyond the scope of this paper, several options may be considered. These may be mechanical or functional interventions. Potential mechanical interventions include orthotics or specialized footwear, or changing the running surface. Possible functional interventions include various types of instruction to retrain gait. CONCLUSION: While acknowledging the limitations of retrospective cross-sectional studies, several biomechanical variables have been identified as having greater magnitude during running in those with previous tibial stress fracture compared to controls. Loading-related variables include vertical ground reaction force loading rates, the magnitude of peak free moment, and peak tibial shock. Kinematic variables include peak knee flexion stiffness during initial loading, peak rearfoot eversion and peak hip adduction.

Medical professionals frequently evaluate infants and children with head trauma. If the child's cranial injuries are not explained by the history, child abuse must be considered. A significant body of research regarding cranial injury mechanisms is available. This article presents a synthesis of a subset of the biomechanics literature relevant to head injury. The potential application of this knowledge base is explored through five questions: (a) What physical laws govern the response of the head-brain complex to the application of a mechanical force? (b) What are the causal mechanisms of head injury? (c) What properties of living tissues affect responses to the application of a mechanical force? (d) How can specific cranial injuries be linked to their biomechanical origins? and (e) Can the biomechanical history explain the cranial injuries? The authors propose a biomechanics-based paradigm for analysis of pediatric head trauma and seek a qualitative rather than a quantitative understanding.

In the last decade, we have witnessed substantial progress in our understanding of corneal biomechanics and architecture. It is well known that diabetes is a systemic metabolic disease that causes chronic progressive damage in the main organs of the human body, including the eyeball. Although the main and most widely recognized ocular effect of diabetes is on the retina, the structure of the cornea (the outermost and transparent tissue of the eye) can also be affected by the poor glycemic control characterizing diabetes. The different corneal structures (epithelium, stroma, and endothelium) are affected by specific complications of diabetes. The development of new noninvasive diagnostic technologies has provided a better understanding of corneal tissue modifications. The objective of this review is to describe the advances in the knowledge of the corneal alterations that diabetes can induce. ; The authors would like to thank the Spanish Ministry of Economy, Industry and Competitiveness (Project DPI2017-84047-R), CIBER initiative (ISCIII CIBER-BBN), and Government of Aragon through the research group T88 (Fondo Social Europeo).

Disabled people compete at high levels in several sport disciplines and physical activity for this population has become a high interest area of study in biomechanics [...]