Adolescent Experience with Trauma and Orthopedic External Fixation: A Dissertation

Over 13 million adolescents sustain traumatic injuries yearly, resulting in functional disability, disfigurement, psychosocial problems and fractures. These fractures are increasingly being treated with orthopedic external fixation devices (EFDs). The purpose of this study was to describe the experience of traumatically injured adolescents treated with EFDs. The 4 aims of the study focused on the circumstances leading to the traumatic event, experiences following the traumatic event, the impact of EFD treatment, and adolescents’ role in pin-care self-management, which is crucial to preventing infection. This longitudinal, qualitative descriptive study used purposive sampling to recruit 5 male and 4 female adolescents, 13-20 years old, from a New England level-1 trauma center. Participants were injured in motor vehicle crashes (including an all-terrain vehicle), falls, by gunshot, trampoline and football trauma. Interview questions were framed by two themes from a study of adult recovery from physical injury, i.e., the event and fallout. Participants were interviewed within days of the injury, 2 weeks after returning home, and within one month of EFD removal. Data were coded from verbatim transcripts using NVIVO and organized into themes guided by the principles of qualitative analysis. An overarching theme of “old self no more; forever changed” emerged from 26 interviews. The participants’ experience affected all tasks of adolescence: independence from parents, accepting body image, peer relations, and forming an identity. Major themes included “what risk?”, regarding circumstances leading to the traumatic event, mastering the environment, was 2 part first, processing the event, where determining fault and realizing everything has changed, they were ambivalently lucky, and not invincible. Secondly “suck it up and deal with it”, where strategies to deal with traumatic injury emerged (i.e. medication, channeling outlets, and slow caution). EFD experience revealed “Space age robot” and “they’ll do it themselves” as emergent themes. EFDs were described as painless, robotic, no big deal and necessary. One draining pin-site was noted. Findings related to use of self-administered analgesics, information technology, recall of detail, and gender differences in coping may lead to future interventions. These findings lay the groundwork for future studies that may improve care of adolescents during acute recovery from traumatic injury

The most difficult at-fault fatal crashes to avoid with current active safety technology

Objective We studied which current fatal at-fault crashes would occur despite the most advanced current active safety devices (up to SAE level 2 of driving automation) and how frequent these crashes would be. Methods We carried out a cross-sectional study of passenger cars that were first registered during the period 1st January 2010 to 31st December 2017 in Finland. To gain the true exposure for these cars, we accessed the national Vehicular and Driver Data Register to obtain the mileage information and the registration count for the study period of 2010-17. Similarly, we accessed the registry of Finnish road accident investigation teams and included all fatal at-fault crashes among the cars in our study for the same period. We used a real world reference technology for each active safety system in our analysis and chose one car brand as an example. This gave us exact system specifications and enabled testing the operation of the systems on the road. We performed field tests to gain further information on the precise operation of the safety systems in different operating conditions. Finally, we gathered all information on the studied active safety systems and analyzed the investigated at-fault fatal crashes case-by-case using our four level method. Results Cars in our study were the primary party in 113 investigated fatal accidents during the years 2010-17. In 87 of the accidents, the leading cause of death was the injuries due to the crash, and these cases were classified as “unavoidable” (n = 58, 67 %), “avoidable” (n = 26, 30 %) or unsolved (n = 3, 3 %). Of the 58 “unavoidable” crashes 21 (36 %) were suicides, 21 (36%) involved active driver input which would have prevented the safety system operation, 15 (17 %) featured circumstances beyond the safety system performance and in one loss-of-control crash the driver had disabled the relevant safety system (electronic stability control). The registration years of the cars in our study (2010-17) totaled 3,772,864 and during this period, the cars travelled 75.9 billion kilometers. The crash incidence of the “unavoidable” at-fault fatal crashes was 0.76-0.80 fatal crashes per billion kilometers and 15-16 fatal crashes per million registration years. Conclusions We calculated a crash incidence for the “unavoidable” crashes which was 20–27% smaller than the observed crash rate of ESC-fitted passenger cars in our previous study. We concluded that suicides, active driver input until the crash, and challenging weather and road conditions are the most difficult factors for current active safety systems. Our analysis did not account for issues such as system usability or driver acceptance and therefore our results should be regarded as something that is currently theoretically achievable. However, the observed incidence is a good reference for automated driving development and the crash rate of automated cars.Peer reviewe

Deterministic Partial Differential Equation Model for Dose Calculation in Electron Radiotherapy

Treatment with high energy ionizing radiation is one of the main methods in modern cancer therapy that is in clinical use. During the last decades, two main approaches to dose calculation were used, Monte Carlo simulations and semi-empirical models based on Fermi-Eyges theory. A third way to dose calculation has only recently attracted attention in the medical physics community. This approach is based on the deterministic kinetic equations of radiative transfer. Starting from these, we derive a macroscopic partial differential equation model for electron transport in tissue. This model involves an angular closure in the phase space. It is exact for the free-streaming and the isotropic regime. We solve it numerically by a newly developed HLLC scheme based on [BerCharDub], that exactly preserves key properties of the analytical solution on the discrete level. Several numerical results for test cases from the medical physics literature are presented.Comment: 20 pages, 7 figure