Biomechanics

Biomechanics is a vast discipline within the field of Biomedical Engineering. It explores the underlying mechanics of how biological and physiological systems move. It encompasses important clinical applications to address questions related to medicine using engineering mechanics principles. Biomechanics includes interdisciplinary concepts from engineers, physicians, therapists, biologists, physicists, and mathematicians. Through their collaborative efforts, biomechanics research is ever changing and expanding, explaining new mechanisms and principles for dynamic human systems. Biomechanics is used to describe how the human body moves, walks, and breathes, in addition to how it responds to injury and rehabilitation. Advanced biomechanical modeling methods, such as inverse dynamics, finite element analysis, and musculoskeletal modeling are used to simulate and investigate human situations in regard to movement and injury. Biomechanical technologies are progressing to answer contemporary medical questions. The future of biomechanics is dependent on interdisciplinary research efforts and the education of tomorrow’s scientists

Prevention of neck injury in frontal impacts

'Whiplash' or Soft Tissue Neck Injwy (STNI) has traditionally been recognized as a car-to-car rear impact phenomenon; studies worldwide verify that the risk of sustaining neck injury in a car crash is approximately three-fold the risk of sustaining the same injury in other crash-types. In general, as such injuries are not characterized by a high risk of threat-to-life (as measured by internationally adopted injury severity scales such as the Abbreviated Injury Scale), prevention of them has perhaps not been seen as a high priority. However, in recent times, it has been recognized that such injury can be very debilitating to those afflicted and costs to sociery as a result of the injury can be correspondingly high. Techniques have therefore evolved over the past 5-l0 years that are aimed at the prevention of neck injury, mostly in rear impacts, and these are predominantly based on current understandings of the actual injurycoupled with the injury mechanism. Such studies usually indicate that the design of vehicle seat and head restraint is critical in the prevention of neck injury. However, neck injury does not only occur in rear-end crashes. Some studies have shown that the risk of sustaining neck injury in front and side impacts is between 15-20%. As these crash-types occur more frequently than rear impacts, the actual exposure to neck injury could be higher than in rear impacts. However, so far there have been no design techniques specifically aimed at neck injury prevention in such impacts. Recently, two studies of real-world crashes have examined the effects of arl-bags in frontal impacts. These are reported in this paper. Both studies have shown that the deploying air-bag in conjunction with a seat belt in a frontal crash can significantly reduce the incidence of neck injury in a frontal impact. The first is an on-going study of vehicle crash performance and occupant injury which is being conducted by Folksam Insurance in Sweden using data obtained from on-board crash recorders. The second study uses preliminary data from an on-going study of vehicle crash peiformance and occupant injury, which is being conducted by the Monash Universiy's Accident Research Centre

Upper limb-rehabilitation service system for chinese mild-stroke patients at home

With the continuous growth in the popularity of stroke patients in China and the increasing demand for rehabilitation services, the existing traditional hospital rehabilitation model can no longer meet the patients’ needs. In recent years, the Chinese government has focused on promoting a new model of “Internet plus medical care” and home rehabilitation. Of all the symptoms of the stroke, upper limb motor dysfunction is the most common one that causes the decline of the patients’ self-care ability and quality of life. Therefore, continuous rehabilitation training plays a vital role in the recovery of limb motor function in stroke patients with hemiplegia and can also serve as a starting point for remote rehabilitation. This thesis first summarized the fundamental upper limb movements as well as theories, high technologies and assessment methods of upper limb rehabilitation. All the literature review assists designers in understanding the necessary medical knowledge of stroke and rehabilitation. Secondly, the existing products and services of upper limb rehabilitation in China and at abroad are compared and analyzed to explore more design opportunities. Furthermore, based on the observations and interviews, the author summarized the rehabilitation needs, information needs and emotional needs of stroke patients in Shanghai, investigated design pain points, and selected target users for remote rehabilitation. Finally, a support remote upper limb rehabilitation system concept was established by adopting service design approaches and tools. Furthermore, the concept of a home rehabilitation device and a digital platform, which were two main touchpoints in this system were designed in-depth and made into the prototype for user feedback. The home rehabilitation device integrated a variety of hand grasping exercises by modularization and integrated different upper limb movements through a point-to-line method to solve the problem of lacking multi-function and miniaturization in the home environment. The digital platform used visual interfaces to provide patients with clear instructions and incentive mechanisms which prevent them from giving up rehabilitation halfway. The findings of this thesis indicated the importance of service design approaches and tools on systemic thinking and creative ideas. The design results of this project can not only help stroke patients to perform active exercises at home and improve their upper limb motor function, but also provide new visions for the development of future remote rehabilitation service system in China

A review of secondary safety priorities

This report identifies passenger car occupant safety issues that can be considered priorities for injury mitigation through secondary safety interventions. The results are relevant to a newer car fleet designed to meet the current regulatory and consumer test requirements. Some suggestions were made for secondary safety interventions but the general conclusion for all areas was that more understanding of the injury mechanisms, further enhanced biomechanical data, and improved dummy bio-fidelity were required before the most effective countermeasures (including both changes in regulation and vehicle design) could be determined and their respective benefits quantified. The main conclusion from this study is that whilst various priority areas have been identified and some secondary safety interventions suggested, the benefit that these would have in mitigating injury is unclear since some injury mechanisms are still largely undefined. It would be inadvisable to simply implement design solutions/develop new regulation without due consideration to the shortfall in current biomechanical knowledge and the limitations of the current test procedures/tools in predicting injury outcome under real world crash conditions. In addition to the main study, a pilot driver survey was carried out to gain knowledge of public opinion and perception of car safety as an influencing factor in vehicle purchase. This survey demonstrated a potential methodology but the results are limited due to the small sample size. This report is intended as a summary of the extensive work that has been undertaken for the project. There are a number of substantial appendices which document the in-depth research undertaken on which this summary report is based. The project was conducted in a number of stages. Issues have been identified through analysis of national and in-depth accident data sets, through workshops held with experts in the field of vehicle safety (Project Consultative Group), and through a review of the literature. Throughout the project consultations have been held with the Department for Transport. National accident data highlighted the continued importance of car occupant injury mitigation within the accident constellation. Further priority areas for passenger car occupants were then defined primarily according to the frequency of the injury, the cost to society of the injury, and through the existing knowledge base across members of the Project Consultative Group (PCG). A total of 18 priority areas have emerged relating to injury mitigation in frontal, side, rear, rollover and multiple impact configurations. Additionally, 6 areas were identified concerned with associated issues such as vulnerable road users. For each of these an indication of the extent of current research activity is given and recommendations made for further actions that could be undertaken to advance the current knowledge. Consensus was sought among the PCG members for 5 leading priority areas and the potential for injury mitigation through secondary safety intervention by means of vehicle design or regulatory compliance was explored by means of a workshop. These 5 areas were femur fractures in frontal impact, foot/ankle injuries in frontal impacts, chest injuries in struck side impacts, whiplash in frontal impacts and rear occupant protection in frontal impacts

A review of the effectiveness of lower limb orthoses used in cerebral palsy

To produce this review, a systematic literature search was conducted for relevant articles published in the period between the date of the previous ISPO consensus conference report on cerebral palsy (1994) and April 2008. The search terms were 'cerebral and pals* (palsy, palsies), 'hemiplegia', 'diplegia', 'orthos*' (orthoses, orthosis) orthot* (orthotic, orthotics), brace or AFO

Hormonal Contraceptive Use Among Active Duty Army Servicewomen. Trends and Implications for Risk of Musculoskeletal Injury.

Almost 40% of servicewomen use hormonal contraception every year, and 60% will use a contraceptive method in their military career. Rates of contraceptive use and musculoskeletal injury are higher among servicewomen as compared to civilians. Gender differences in rates of musculoskeletal injury have led investigators to question the role of sex hormones, including contraception. Recent studies suggest that hormonal contraceptives may decreased risk of anterior cruciate ligament (ACL) injury, potentially decreasing early onset osteoarthritis (OA). We utilized the Total Army Injury and Health Outcome Database, which prospectively captured demographics, clinical and pharmacy records on over 5.6 million Army soldiers since 1994. Hormonal contraceptive use was identified in the Pharmacy Data Transaction Service. The first project described changes in covariates and contraceptive use overtime. Over the ten years of follow-up, there were increases in age, education, and rank of servicewomen at entry. Among contraceptive users, rates of pill use decreased from 79.71% in 2002 to 51.67% in 2011 with increased use of the ring, implant and IUD. Contraceptive users were young, higher ranking and more likely to be nulliparous. Education varied widely by contraceptive method with injection and patch users having the lowest and ring users the highest level of education. The second and third projects examined the association of hormonal contraceptive and ACL injury or OA by survival analysis using multivariate Cox proportional hazards models. In project two, a total of 2,253 incident ACL tears were identified from medical billing codes. In our final model, current users were 15% less likely to have incident ACL injury. Project 3 identified a total of 3,943 OA cases. In the final model, ever use of contraceptive was associated with a 19% reduced risk of OA compared to never users. Strengths of our study include the evaluation of all types of contraceptive use in a large, diverse, population-based cohort. Information gathered from this study informs future studies considering hormonal contraceptives a modifiable risk factor for ACL injury and OA, informing contraceptive decision making, clinical recommendations, and injury prevention strategies for servicewomen particularly around key career events including basic training and deployment

Biomechanics of the Upper Extremity in Response to Dynamic Impact Loading Indicative of a Forward Fall: An Experimental and Numerical Investigation.

The distal radius is one of the most common fracture sites in humans, often resulting from a forward fall with more than 60 % of all fractures to the wrist requiring some form of surgical intervention. Although there is a general consensus regarding the risk factors for distal radius fractures resulting from forward falling, prevention of these injuries requires a more thorough understanding of the injury mechanisms. Therefore the overall purpose of this dissertation was to assess the response of the upper extremity to impact loading to improve the understanding of distal radius fracture mechanisms and the effectiveness of joint kinematic strategies for reducing the impact effects. Three main studies were conducted that utilized in vivo, in vitro and numerical techniques. In vitro impact testing of the distal radius revealed that fracture will occur at a mean (SD) resultant impact force and velocity of 2142.1(1228.7) N and 3.4 (0.7) m/s, respectively. Based on the failure data, multi-variate injury criteria models were produced, highlighting the dynamic and multidirectional nature of distal radius fractures The in vitro investigation was also used to develop and validate a finite element model of the distal radius. Dynamic impacts were simulated in LS-DYNA and the resulting z-axis force validation metrics (0.23-0.54) suggest that this is a valid model. A comparison of the experimental fracture patterns to those predicted numerically (i.e. von-Mises stress criteria) shows the finite element model is capable of accurately predicting bone failure

Occupational Therapy Resource Guide for the Utilization of Three-Dimensional Printing

Many practitioners in the field of occupational therapy are unaware of the benefits and importance of implementing a three-dimensional (3D) printer in practice indicating that there is a need for occupational therapy involving the fitting, environmental modifications, and training on how to properly use a 3D printed prosthetic within the upper extremity. 3D printing is when a digital design is converted into a designed material that has a functional purpose and different materials can be used including metal, plastics, and composite materials (Thomas & Claypole, 2016). 3D printing has many unique and effective uses like creating adaptive devices, feeding devices, prosthesis, and splinting. While 3D printing is currently being implemented across certain pediatric populations creating prosthesis, a lack of evidence was noted regarding the use of a 3D printer throughout occupational therapy. (Burn, M. B., Anderson, T., & Gogola, G. R., 2016). This is unfortunate as 3D printing is an innovative field of study that can aid many populations in becoming more independent and functional in daily tasks while increasing quality of life. A comprehensive literature review on the populations that utilize printing was conducted. The lack of occupational therapy involvement in the transition process of creating and training for the use of a 3D prosthetic, yields the demand for occupational therapy services. The information obtained aided in the development of a resource guide containing the importance of occupational therapy services involved with the transition process of a 3D printing. The literature review led the authors to focus on the main areas of rehabilitation phases, splinting and prosthetics, adaptive equipment, 3D printers, printing filaments, and various safety considerations. The integration of occupational therapy in 3D printing will greatly ease the clients’ transitions during rehabilitation phases while increasing their level of function and quality of life. 3D printing is a cost effective, user-friendly, creative, and innovative approach to add to practice. 3D printing is an up-and-coming area of occupational therapy and has the potential to change lives

Injury criteria for vehicles safety assessment: a review with a focus using Human Body Models

This paper aims at providing an overview of the most used injury criteria (IC) and injury metrics for the study of the passive safety of vehicles. In particular, the work is focused on the injury criteria that can be adopted when finite element simulations and Human Body Models (HBMs) are used. The HBMs will result a fundamental instrument studying the occupant’s safety of the Autonomous Vehicles (AVs), since they allow to analyze a larger variety of configurations compared to the limitations related to the traditional experimental dummies. In this work, the most relevant IC are reported and classified basing on the body segments. In particular, the head, the torso, the spine, the internal organs, and the lower limbs are here considered. The applicability of the injury metrics to the analyses carried out with the HBMs is also discussed. The paper offers a global overview on the injury assessment useful to choose the injury criteria for the study of the vehicle passive safety. To this aim, tables resuming the presented criteria are also reported to provide the available metrics for the considered body damage