No description available.

Yes / We read with interest the recent article by Yun et al. [1] comparing acetabular and hip measurements across pelvis, hip and lumbar spine radiographs. The authors assert that lumbar radiographs can be utilised in place of routine pelvis radiographs for these measurements. The example lumbar spine radiograph (figure 2) appears to be an abdominal image, with a contrast urogram. Indeed, standard texts [2,3] confirm that the anteroposterior lumbar spine radiograph should not include any coverage of the hips as appropriate collimation should limit the anatomy to T12 superiorly, lower sacrum inferiorly and the sacroiliac joints laterally, which would exclude the hip joints. Thus assessing any hip measurements on an appropriately collimated lumbar spine radiograph should not be possible. This is further compounded by the description of the centring point within their study (iliac crest), which varies from the internationally recognised standard of lower costal margin/L3 [2,3].

Yes / There is no single, universally accepted method of measuring isometric neck strength to inform exercise prescription and injury risk prediction. This study aimed to establish the inter- and intra-rater reliability of a commercially available fixed frame dynamometer in measuring peak isometric neck strength. A convenience sample of male (n = 16) and female (n = 20) university students performed maximal isometric contractions for flexion (Flex), extension (Ext), left- (LSF) and right-side flexion (RSF) in a quadruped position over three sessions. The intra-rater reliability results were good-to-excellent for both males (ICC = 0.83–0.90) and females (ICC = 0.86–0.94) and acceptable (CV < 15%) across all directions for both males and females. The inter-rater reliability results were excellent (ICC = 0.96–0.97) and acceptable (CV < 11.1%) across all directions. Findings demonstrated a significant effect for sex (p ≤ 0.05): males were stronger in all four directions, and a significant effect for direction (p ≤ 0.05): Ext tested stronger (193 N) than Flex (176 N), LSF (130 N) and RSF (125 N). The findings show that the VALD fixed frame dynamometer can reliably assess isometric neck strength and can provides reference values for healthy males and females.

Due to the mathematical complexity of current musculoskeletal spine models, there is a need for computationally-efficient models of the intervertebral disc (IVD). The aim of this study is to develop a mathematical model that will adequately describe the motion of the IVD under axial cyclic loading and three-dimensional quasi-static loading as well as maintain computational efficiency for use in future musculoskeletal spine models. A viscoelastic standard nonlinear solid (SNS) model is introduced within this study. It was developed to predict the axial response of the human lumbar IVD subjected to low-frequency vibration. Nonlinear axial behavior of the SNS model was simulated by a strain-dependent elastic modulus on the standard linear solid (SLS) model. The SNS model was able to predict the dynamic modulus of the IVD for frequencies of 0.01, 0.1, and 1 Hz. Furthermore, the model was able to quantitatively predict the load relaxation at a frequency of 0.01 Hz. However, model performance was unsatisfactory when predicting load relaxation and hysteresis at higher frequencies (0.1 Hz and 1 Hz). Results suggest that the standard solid model may require strain-dependent elastic and viscous behavior to represent the dynamic response to compressive strain. The SNS model was expanded to a three-dimensional elastic model by adding a matrix of spring elements in parallel with the SNS model. The geometry and orientation of the added elements represent the regional variations in stiffness and physiologic fiber angle. Results suggest that lordotic posture may be advantageous when modeling the intervertebral joint (IVJ) behavior. / Master of Science

by Chan Kwai Foon May. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 103-114). / Abstracts in English and Chinese. / Declaration --- p.2 / Abstract --- p.3 / Abstract in Chinese --- p.6 / Acknowledgements --- p.8 / Chapter Chapter 1. --- Introduction --- p.15 / Chapter Chapter 2. --- Osteoporosis : The relationship between aging and skeletal organization between men and women --- p.17 / Chapter 2.1. --- Skeletal organization --- p.17 / Chapter 2.1.1. --- Bone structure --- p.17 / Chapter 2.1.2. --- Bone metabolism --- p.17 / Chapter 2.1.3. --- Peak bone mass --- p.18 / Chapter 2.2. --- Bone loss between men and women --- p.20 / Chapter 2.2.1. --- Aging and bone loss --- p.20 / Chapter 2.2.2. --- Clinical aspects of bone loss in men and women --- p.21 / Chapter Chapter 3. --- Vertebral deformity : Bone Mineral Density and Body Composition --- p.23 / Chapter 3.1. --- Bone mineral density --- p.23 / Chapter 3.1.1. --- Types of vertebral deformity --- p.23 / Chapter 3.1.2. --- Clinical diagnosis in vertebral deformity --- p.24 / Chapter 3.1.3. --- Bone mineral density measurements --- p.25 / Chapter 3.1.4. --- Vertebral deformity and bone mineral density --- p.28 / Chapter 3.2. --- Bone composition --- p.33 / Chapter Chapter 4. --- Literature Review on Health Consequences of Vertebral Deformity --- p.36 / Chapter 4.1. --- Back pain --- p.36 / Chapter 4.1.1. --- Back pain and vertebral deformity --- p.36 / Chapter 4.1.2. --- Back pain in men and women with vertebral deformity --- p.38 / Chapter 4.2. --- Morale and functional limitation and vertebral deformities --- p.39 / Chapter 4.2.1. --- Function evaluation : The Barthel Index --- p.40 / Chapter 4.2.2. --- Philadelphia Geriatric Morale Scale --- p.41 / Chapter Chapter 5. --- Objectives --- p.43 / Chapter Chapter 6. --- "Subjects and methods for phase I: anthropometric measurement, body composition and bone mineral density measurement in vertebral deformity patients and controls" --- p.44 / Chapter 6.1. --- Study subjects --- p.44 / Chapter 6.2. --- Radiology and digitization protocol for diagnosis vertebral deformity --- p.46 / Chapter 6.3. --- Diagnosis of vertebral deformity --- p.48 / Chapter 6.4. --- Body composition and bone mineral density measurements --- p.54 / Chapter 6.4.1. --- Body composition analysis --- p.54 / Chapter 6.4.2. --- Lumbar spine and hip bone mineral analysis --- p.54 / Chapter 6.5. --- Quality control --- p.56 / Chapter 6.5.1. --- Routine quality control of measurements --- p.56 / Chapter 6.5.2. --- Precision on patient repositioning --- p.56 / Chapter Chapter 7. --- Subjects and methods for phase II: health consequences of vertebral deformity patients and controls --- p.57 / Chapter 7.1. --- Questionnaire on health consequences --- p.57 / Chapter 7.1.1 --- Back pain and disability --- p.57 / Chapter 7.1.2 --- Activities of daily living --- p.59 / Chapter 7.1.3 --- Morale --- p.59 / Chapter 7.2. --- Statistical methods --- p.60 / Chapter 7.2.1. --- Bone mineral density and body composition --- p.60 / Chapter 7.2.2. --- Back pain and disability --- p.60 / Chapter 7.2.3. --- Activities of daily living and morale --- p.61 / Chapter Chapter 8. --- "Results for phase I: anthropometric measurement, body composition and bone mineral density measurement in vertebral deformity patients and controls" --- p.62 / Chapter 8.1. --- Demographic characteristics of study population --- p.62 / Chapter 8.2. --- Anthropometric measurements : Body composition and bone mineral density --- p.64 / Chapter Chapter 9. --- Results for phase II: Health Consequences of vertebral deformity patients and control --- p.76 / Chapter 9.1. --- Back pain --- p.76 / Chapter 9.2. --- Disability --- p.78 / Chapter 9.3. --- Activities of daily living --- p.81 / Chapter 9.4. --- Morale --- p.82 / Chapter Chapter 10. --- Discussion I --- p.83 / Chapter 10.1. --- Study Sample --- p.83 / Chapter 10.2. --- Digitization method and definition of vertebral deformity --- p.84 / Chapter 10.3. --- Methods for bone mineral density measurement --- p.87 / Chapter 10.4. --- Questionnaire validity --- p.88 / Chapter 10.4.1. --- Back pain and disability --- p.88 / Chapter 10.4.2. --- Barthel Index --- p.88 / Chapter 10.4.3. --- Philadelphia Geriatric Morale Scale --- p.89 / Chapter Chapter 11. --- Discussion II --- p.92 / Chapter 11.1 . --- Body composition and bone mineral density --- p.92 / Chapter 11.2. --- Differences of vertebral deformity between Chinese men and Caucasian men --- p.93 / Chapter 11.3. --- Health consequences in Chinese men --- p.96 / Chapter 11.4. --- Comparison of health consequences between Chinese men and Caucasian men --- p.98 / Chapter 11.5. --- Variation of health consequences between Chinese men and Chinese women --- p.101 / Chapter 11.5.1. --- Back pain and disability --- p.101 / Chapter 11.5.2. --- Morale --- p.102 / Chapter Chapter 12. --- Conclusion --- p.103 / Reference --- p.104 / Appendix I --- p.115 / Appendix II Publication

Made available in DSpace on 2016-01-26T12:51:47Z (GMT). No. of bitstreams: 1 fernandofilipe_dissert.pdf: 443784 bytes, checksum: bb6328cd8296f1c4b222d0c43cdafda1 (MD5) Previous issue date: 2006-02-13 / Adjacent segment disease is defined as an abnormal process developing in the adjacent level above and/or bellow the arthrodesis of the segment. It is considered a late complication of lumbar spine arthrodesis. It has been very important due to the procedures in the last years. Objective: To evaluate the risk factors associated with the disease at adjacent level as well as its relationship with the natural history of degenerative disease of the lumbar spine. Material and Methods: This was a retrospective study, from January 2000 to December 2002.Thirty-eight patients undergoing arthrodesis in the lumbosacral spine using the pedicle screw fixation participated in the study. Results: These patients had a mean follow-up of 30 months; 10 patients presented adjacent segment disease, 7 disc degeneration, 2 spinal stenosis and one discal spine hernia. The patients´ mean age was 48.5 years; female sex was the majority. Degeneration occurred in 4 patients with stenosis; 4 with spondylolisthesis, and 1 with post disc hernia; all these had been submitted to arthrodesis of lumbosacral spine. The majority was asymptomatic, after being treated by arthrodesis in multiple levels. There was no statistical difference when the above factors were related. Conclusion: Adjacent segment disease is a late complication in the arthrodesis of lumbosacral spine with no relationship of risk factors presented in this study. Therefore, its origin could be related with the natural history of the degenerative disease of lumbar spine. / A doença do nível adjacente é definida como um processo anormal que se desenvolve no nível adjacente, acima e/ou abaixo do segmento artrodesado. Considerada como uma complicação tardia da artrodese da coluna vertebral, tem-se tornado muito importante em decorrência do aumento dos procedimentos nos últimos anos. Objetivo: Avaliar os fatores de risco associados à ocorrência da doença do nível adjacente e sua relação com a história natural da doença degenerativa da coluna vertebral. Material e métodos: Análise retrospectiva de janeiro de 2000 a dezembro de 2002, realizada em 38 pacientes submetidos a artrodese de coluna lombosacra com a utilização de parafuso pedicular. Resultado: Os pacientes analisados apresentavam follow up médio de 30 meses, com a presença de 10 pacientes com doença do nível adjacente; sendo 7 com degeneração discal, 2 com estenose de canal vertebral e 1 com hérnia de disco. A idade média dos pacientes foi 48,5 anos, com predomínio no sexo feminino. A degeneração ocorreu em 4 pacientes com estenose de canal, em 4 pacientes com espondilolistese, em 1 paciente com escoliose e em 1 paciente pós hérnia de disco, os quais tinham sido submetidos a artrodese da coluna lombosacra. A maioria dos pacientes foram submetidos a artrodese em múltiplos níveis e apresentavam-se assintomáticos. Nenhuma diferença estatística foi evidenciada quando relacionados os fatores acima. Conclusão: A doença do nível adjacente é uma complicação tardia existente na artrodese de coluna lombosacra, não relacionada aos fatores de risco apresentados; portanto o seu aparecimento estaria relacionado à história natural da doença degenerativa da coluna lombar.

This thesis examines the rapid, non-genomic effects of estrogens on neural plasticity and learning. Estrogens are classically known to affect gene transcription events, however they have more recently been found to also rapidly activate second messenger systems within 1hr of administration. Therefore, we first examined the rapid effects of 17β-estradiol, and an estrogen receptor (ER) α and ERβ agonist on three different learning paradigms: object placement, object recognition, and social recognition. We found that both systemic injections and intrahippocampal delivery of 17β-estradiol and the ERα agonist improved performance on all 3 learning paradigms within 40min of hormone administration. However, the ERβ agonist administered systemically or intrahippocampally, improved performance only on the object placement learning paradigm, while having no effect on object recognition, and impairing social recognition at high doses. To elucidate how estrogens might rapidly affect learning, we examined how estrogens rapidly affect the neural plasticity of CA1 hippocampal neurons. We found that 17β-estradiol and the ERα agonist increased dendritic spine density in CA1 hippocampal neurons within 40min of administration, suggesting that estrogens rapidly increase the density of synapses within this brain region. Conversely, the ERβ agonist did not affect spine density, or decreased spine density. In addition, by using whole-cell patch clamp recordings of CA1 pyramidal neurons, we were able to determine that 17β-estradiol and the ERα agonist rapidly reduced AMPA receptor (but not NMDA receptor) mediated membrane depolarizations after 15min of hormone application. Similar to above, the ERβ agonist had no effect on AMPA or NMDA receptor mediated membrane depolarizations. These data suggest that estrogens rapidly promote the development of immature synapses (which contain low levels of synaptic AMPA receptors) within the CA1 hippocampus. Immature spines provide synaptic sites at which new memories can be stored and are thought of as “learning spines” (Kasai et al, 2003). Therefore, estrogens (through ERα) may rapidly induce the formation of hippocampal immature spines to promote learning. / Funded by NSERC

No description available.

Submitted in partial compliance with the requirements for the Masters’ Degree in Technology: Chiropractic, Department of Chiropractic, Durban University of Technology, Durban, South Africa, 2014. / Background Spinal manipulative therapy (SMT) is a commonly used therapeutic modality. It has been shown that neuromuscular reflexes are elicited during spinal manipulation resulting in changes in the surrounding muscle tonicity and seen as changes in surface electromyography. Despite this little is known about the effect that SMT may have on muscle function. Increased maximum voluntary contraction (MVC) of the paraspinal muscles has been observed following lumbar SMT compared to a control and sham treatment; however its effect on muscle endurance has not been investigated. The aim of this study was to determine the effect of lumbar SMT compared to a placebo treatment on lumbar extensor muscle endurance in asymptomatic individuals. Method This study was a quantitative double blinded, pre-test and post-test placebo controlled experimental trial. Forty asymptomatic participants were randomly allocated to one of two treatment groups. One group received a single SMT applied to the L3 vertebrae and the other received the pre-load force of the SMT but no thrust. Subjective (a self-report of pain/discomfort while performing the Biering-Sorensen test) and objective [surface electromyography (sEMG), paraspinal muscle endurance time and lumbar spine range of motion] measurements were taken pre- and post-intervention. The latest version of SPSS version (IBM SPSS Inc.) was used to analyse the data. A p-value < 0.05 was considered statistically significant. Independent t-tests were used to compare means and two-way factor ANOVA (for repeated measures) was used to compare the change in the two time points between the two treatment groups (intervention and control). RESULTS There were no statistically significant differences between the intervention and placebo groups in terms of subjective reports of pain/discomfort and objective evidence of surface EMG readings, paraspinal muscle endurance time and lumbar spine range of motion.

No description available.