<p>The National Spinal Cord Injury Statistical Center estimates there are 12,500 new cases of spinal cord injury (SCI) in the United States every year (www.nscisc.uab.edu, 2014) and vehicular crashes are the leading cause. Spinal injuries can have extensive long term consequences leading to widespread social and economic costs as well as the human cost of living with chronic, sometimes debilitating, pain (Côté et al. 1998, Côté et al. 2001, Daffner et al. 2003, Harrop et al. 2001, Sekhon et al. 2001). Within the military population, spinal injuries are a common result of repeated loading from high-speed planing watercraft (Bass et al. 2005, Gollwitzer et al. 1995, Schmidt et al. 2012), high performance aircraft (Coakwell et al. 2004, de Oliviera et al. 2005), and underbody blast exposure (Vasquez et al. 2011, Wilson 2006). Therefore, there is interest within the automotive, military, and clinical communities to understand the biomechanics the failure mechanics of the osteoligamentous structures in the spine.</p><p>Acoustic emissions have been shown to be produced during micro-cracking of cortical bone (Kohn 1995). However, there has been minimal work utilizing acoustic emission to detect cortical and trabecular bone damage. The research in this dissertation developed experimental and analytic methods of sensitively assessing when failure (both micro-cracks and more extensive failures) occurs in the cervical spine using acoustic emissions. </p><p>The acoustic emissions from cortical and trabecular bone failure were characterized using a Welch power spectrum density estimate and continuous wavelet transform. The power spectrum density results showed both cortical bone and trabecular bone failure produced wideband acoustic emission signals with spectral peaks between from 20 kHz to 1380 kHz and 24 kHz to 1382 kHz respectively. The continuous wavelet transform showed the spectral content begins with high frequency content followed quickly by low frequency content, but the low frequency lasts for a longer time causing it to dominate the response in the Welch power spectrum density. The first frequency component in the continuous wavelet transform was used to characterize the signals and was found to form three distinct bands in the cortical bone tests (166 ± 52.6 kHz, 379 ± 37.2 kHz, and 668 ± 63.4 kHz) and one band in the trabecular bone tests (185 ± 37.9 kHz). Therefore, observing spectral content within these bands suggests failure of the respective bone.</p><p>This dissertation also uses continuous wavelet transform to identify failure in whole cervical spine compression tests. Whole cervical spines placed in a pre-flexed and pre-extended posture were compressed to induce failure while being monitored for acoustic emissions. Cortical bone failure was identified in the acoustic emissions when local maxima in the continuous wavelet transform fell within the spectral bands associated with cortical bone failure previously identified. The timing of these failures was matched to the force-displacement response to identify the initiation of failure and the major failure. Cortical bone failure was detected at 70-90% of the failure load suggesting that the failure occurs as an evolution from micro-cracks to the eventual major failure. Locating these micro-cracks before the major failure forms may be useful in the prediction of the location of failure.</p><p> This dissertation also presents a technique to calculate the AE source location for AEs generated from fracture. The primary obstacle for AE source localization in the spine is that the speed of sound is different in cortical bone (Prevrhal et al. 2001), trabecular bone (Cardoso et al. 2003), intervertebral disc (Pluijm et al. 2004), ligaments (Kijima et al. 2009), and also differs based on its direction of travel in cortical bone (Kann et al. 1993) and likely in the other materials. Any algorithm must account for these differences to obtain any useful level of accuracy. The algorithm presented in this dissertation is based on hyperbolic source location algorithms (De Ronde et al. 2007, O'Toole et al. 2012, Salinas et al. 2010) except that it iterates on the speed of sound over a specified range, and convergence is defined as when the solution change is minimized. This procedure calculated the AE source location with a mean error of 5.7 mm and a standard deviation of 3.8 mm.</p><p>The contributions and conclusions of this dissertation provide methodology and results to evaluate the failure mechanics in the spine. Although these procedures were developed for use in the spine, they are of great value to the biomechanics community because they are applicable to every body region. The recommendations presented will serve to better understand the failure mechanics of the human body and will likely lead to better defined and safer standards for protective equipment. It also provides data for the generation of finite element models that require failure criteria.</p> / Dissertation

Aufgrund der Tatsache, dass die Wahl der Therapie bei Wirbelfrakturen der Klasse A3 nach Magerl et al. (1994) weiterhin kontrovers diskutiert wird, wurden in dieser Arbeit die Patientenfälle der Abteilung Orthopädie und Unfallchirurgie der Universitätsmedizin Göttingen betrachtet, die im Zeitraum von 2008 bis 2013 eine Wirbelfraktur im Bereich der Brust- und Lendenwirbelsäule erlitten. Das gesamte Kollektiv umfasst 475 Patienten, von denen 266 männlich und 209 weiblich sind. Es wurden objektive Daten wie GDW, Kyphosewinkel und Wirbelkörperhöhenminderung zu fest definierten Zeitpunkten erhoben. Anhand dieser Daten konnte der Verlauf der Stabilität und sowohl der Korrekturgewinn durch die Therapie als auch der Korrekturverlust während der Nachsorge für die jeweiligen Therapiemethoden erfasst werden. Die Therapiemethoden, die hier verglichen werden, sind die konservative Therapie, die Kyphoplastie, die dorsale und die kombiniert dorsoventrale Stabilisierung. Die in der radiologischen Verlaufskontrolle erhobenen Parameter zeigen, dass bei Frakturen der Klassen A1 und A2, die als stabil gelten, die konservative Therapie zu einem guten Ergebnis führt. Bei A3- Frakturen, bei denen in der internationalen Literatur starke Unstimmigkeit darüber besteht, ob diese Frakturen als stabil oder instabil gelten und wie solche Frakturen im allgemeinen zu behandeln sind, bringt die operative Vorgehensweise klare Vorteile. Zudem können bei kombiniert dorsoventraler Operation noch stabilere Ergebnisse erzielt werden. Für die Rotationsfrakturen stellt sich heraus, dass nach der Entfernung des eingebrachten Osteosynthesematerials ein größerer Korrekturverlust eintritt. Abschließend lässt sich sagen, dass bei isolierten Berstungsfrakturen ohne Beteiligung des Bandapparates die Indikation für die kombiniert dorsoventrale Operation häufiger und frühzeitiger gestellt werden sollte. Außerdem sollte beachtet werden, dass bei instabilen Frakturen die Verlängerung der Tragezeit des Fixateurs einen positiven Einfluss auf den Korrekturerhalt hat.

The purpose of this study was to examine the criterion-related validity of the sit and reach test as a measure of hamstring and low back flexibility in adult males and females. Subjects were 52 males and 52 females, 20 to 45 years of age. Hamstring flexibility was measured using a goniometer. Spinal flexibility was measured using a tape measure and an inclinometer. The sit and reach test was performed according to the AAHPERD Health Related Fitness Test Manual. Data were analyzed using correlations and appropriate descriptive statistics. Conclusions of the investigation were: 1) in adult males 20 to 45, the sit and reach test is a valid measure of hamstring flexibility but has questionable validity as a measure of low back flexibility, 2) in adult females 20 to 45, the sit and reach test is a moderately valid measure of hamstring flexibility and is not a valid measure of low back flexibility.

Title: Effect of forward head posture on postural stabilization measured by postural somatooscillography. Objectives: The aim of this thesis was to assess the influence of the forward head posture on the overall ability of postural stabilization using postural somatooscillography method. Methods: This thesis was prepared using analytical - comparative study. It compared two groups of fifteen subjects using the challenge test "3 steps - standing on one leg" in standart conditions. The measurement was recorded to the Microswing 6.0 and collected data was evaluated by Posturomed Commander. Results: The research did not achieve clear results at all, but in the overall assessment, we could say, that people with forward head posture have different, maybe slightly worse ability of postural stabilization. Keywords: postural stability, forward head posture, Posturomed, cervical spine

Title: Detection of rheological changes in the axial system of pregnant women using the TVS method. Objectives: The aim of this thesis is to evaluace the effect of pregnancy on the biomechanical properties of the spine. Methods: TVS vibration diagnostic methods were applied to six pregnant women twice during pregnancy. It was investigated ability of axial system to dampen vibration spreading through out the spine. The ability of every single segment to damp vibrations were compared with each other at the beginning and during pregnancy. Results: TVS method used for purpose of this paper has been proved adequate to provide information about the resonant frequencies and the total attenuation of the spine with sufficient accuracy, so that the biomechanice changes of axial system during pregnancy could be decidly identified. Comparison of the frequency dependency and total attenuation of spine indicated increase of total attenuation of the spine and also increase of flexibility of the spine in all investigated probands. Keywords: gravidity, pregnancy, axial system, vibrations, TVS, spine

Le but de ce travail est d’améliorer les techniques de mesure cinématique tridimensionnelle (3D) afin d’étudier les schémas cinématiques du complexe de l’épaule et du rachis cervical chez des sujets sains et pathologiques. La première partie de ce travail propose un rappel d’anatomie fonctionnelle, une revue de la littérature de la cinématique du complexe scapulo-huméral et une mise au point sur les techniques de mesure de ces deux complexes articulaires. La deuxième partie de ce travail a pour objectif d’évaluer à partir d’études cliniques originales : - la reproductibilité des techniques de mesure des rotations des complexes scapulo-huméral et cervical et d’en proposer une amélioration par une analyse simultanée des translations du barycentre de la scapula ainsi que par la mesure couplée des deux complexes articulaire. - les schémas cinématiques de la scapula dans différents modèles de pathologies ostéo-articulaires au cours de gestes analytiques et fonctionnels. En conclusion, ce travail de thèse met en évidence : une variabilité intra-individuelle dans la capacité à reproduire un mouvement à l’identique avec le membre supérieur et à conserver la même précision dans le repositionnement de la tête. - des mouvements de translation 3D de la scapula, dont certains de grande amplitude, associés aux rotations des mouvements de faible amplitude du rachis cervical associés aux mouvements du membre supérieur en faveur de son rôle proprioceptif. - des schémas cinématiques scapulaires spécifiques : - de la lésion neurologique en cas de scapula alata dynamique. - de la nature fonctionnelle de la tâche en cas de pathologies ostéo-articulaires communes / The aim of this work was to improve the methods of kinematic assessment of the shoulder complex and of the cervical spine in order to improve understanding of scapular and cervical spine kinematics in asymptomatic and symptomatic subjects. The first part of this work provides a reminder of functional anatomy, a literature review of the 3D kinematics of the shoulder complex and issues relating to measurement techniques of both articular complexes. The second part is based on original clinical studies assessing: - the reliability of the measurement techniques of the rotations of both articular complexes and their enhancement by addition of scapular translations and the coupled mobility of the cervical spine and shoulder complexes. - the patterns of scapular kinematic in different ostéo-articular pathologies In conclusion, this work highlights: - intra-individual variability in the ability to reproduce a movement with the upper arm and in the accuracy of repositioning the head . -3D scapular translations (some with large ranges) associated with scapular rotations. - small movements of the cervical spine associated with upper limb movements relating to the proprioceptive role of the cervical. - spine specific scapular kinematic patterns depending on: - neurological lesions in the case of dynamic scapula alata, - the type of movement in common osteo articular pathologies

Title of thesis: Influence of intra-abdominal pressure on the stability of the lumbar spine Definition of the problem: This thesis addresses the problem of the stabilization mechanism of the lumbar spine and the influence of intra-abdominal pressure on the stability of the lumbar spine. Objectives: The aim of my thesis is to locate, evaluate and process all available resources and to bring up the issue of IAP and its influence on the lumbar spine. The work should provide the widest possible insight into the problems of IAP effects on the stability of the lumbar spine, summarize differing opinions, and allow easier orientation in the isme. Method: The work is treated as a search, focusing on the processing and retrieval of literature concerning the issue. Studies included range from 1953 to present. To which I will use a variety of sources of literature, internet and consultation with the head of my thesis. Results: The increase in IAP, which is provided by a synchronous contraction of the diaphragm, pelvic floor muscles and m. transversus abdominis, can effectively stabilize the spine. But you can not determine with certainty whether this mechanism to support the stability of the lumbar spine is indeed used or the stability is provided by contraction of muscles, leading to an increase in IAP, and...

Title: Degenerative changes in the cervical spine with a focus on the intervertebral disc prolapse and its verification using imaging methods and 3D model Objectives: The aim of this work is to describe the problems of degenerative changes in the cervical spine with a focus on the intervertebral disc prolapse. The second part deals with the possibility of imaging methods that are able to detect pathological processes. Part of this work is the study of three cases of patients with a diagnosis of disc herniation. In conclusion, there are some possibilities of 3D modeling of the cervical spine. Methods: The theoretical part is based on the available literature. Images from MRI were obtained from medical facilities in Prague, described and assessed by a specialist. After studying the functions suitable graphical programs were created 3D models of the cervical spine. Results: Degenerative changes in the cervical spine naturally come from the aging of the organism, but a number of modifiable factors accelerating the onset. Among such factors include especially hypokinesia and unilateral overloading of cervical spine. Modern imaging techniques can in detail detect these pathological processes, but are limited by the patient's position during the investigation. The resulting series of images are used as...

Title: Human axial system: identification of connective tissues changes Objectives: The main objective of this thesis was to compile a review of techniques and methods currently used in identification of connective tissues changes. Methods: The method used in this thesis is a critical literature review - a study of research papers from available information sources accompanied by author's comments. Foreign sources are represented mostly by research papers accessible via electronic archives such as ScienceDirect, Pubmed, Springer, Wiley. Also other foreign publications were used. The theoretical part is focused on basic anatomy and physiology of the spine and states main methods of identification of connective tissues changes involved in this area. The main part describes particulars of researches dedicated to identification of functional and morphological characteristics of different spinal components. Results: In addition to classic methods of spinal research, the thesis introduces also new developing techniques and methods. Procedures used in current research are described; their advantages and limits are explained. Key words: spine, biomechanics, loading, intervertebral disc, method

Different psychosocial factors influence the experience and adaptation to pain. Previous cluster analytic studies using the Minnesota Multiphasic Personality Inventory-2nd edition described psychologically different subgroups of pain patients that had been shown valuable in determining outcome. However, these studies had limited applicability to medico-legal pain populations because they did not use newly developed scales or describe important medico-legal factors that have large effects on symptom endorsement. Using three methods of clustering, the current investigation explored the subgroups that resulted when using all the MMPI-2 and the newly developed MMPI-2-RF (Restructured Form) scales on a large and well-described population of medico-legal spine pain patients. Result demonstrated that the best solution for the current sample was the two-cluster solution when a traditional method was used. However, the best solution was the three-cluster solution when all MMPI-2 scales and a method that used all MMPI-2-RF scales were used. Thus, the three-cluster solution was considered the most adequate solution to differentiate patients in medico-legal settings. Moreover, results demonstrated that subgroup membership was not conditioned to spine related organic factors. Instead, malingering, education, ethnic background and legal status differentiated pain subgroups. Lastly, results demonstrated a dose-response relationship between perceived outcome and subgroup profile elevation. The current results are relevant for understanding the circumstances that can influence spine pain recovery and for informing decisions regarding possible interventions.