Background: Football (Soccer) is arguably the most popular sport in the international sporting arena. A survey conducted by FIFA (Fédération International de Football Association) (FCPA, 2000) indicated that there are 240 million people who regularly play soccer around the world. Internationally, there are 300 000 clubs with approximately 1.5 million teams. In South Africa, there were 1.8 million registered soccer players in 2002/2003 (Alegi, 2004). Although youth players are predominantly amateurs and have no financial value for their clubs or schools, their continued health and safety are still of vital importance. There are some clubs which contract development players at 19 years of age in preparation for playing in their senior sides and these young players should be well looked after, to ensure a long career playing soccer. Being able to predict injuries and prevent them would be of great value to the soccer playing community. Aims: The main aim of this research was to create a statistical predictive equation combining biomechanics, balance and proprioception, plyometric strength ratios of ND/Bil (Non dominant leg plyometrics/ Bilateral plyometrics), D/Bil (Dominant leg plyometrics/ Bilateral plyometrics) and ND+D/Bil (Non dominant leg + dominant leg plyometrics/ Bilateral plyometrics) and previous injuries to determine a youth soccer player's risk of the occurrence of lower extremity injuries. In the process of reaching this aim it was necessary to record an epidemiological profile of youth soccer injuries over a two season period. It was also necessary to record a physical profile of, and draw comparisons between, school and club youth soccer players. Following the creation of the prediction model a preventative training programme was created for youth soccer players, addressing physical shortcomings identified with the model. Design: A prospective cohort study Subjects: Schoolboy players from two schools in the North West Province, as well as club players from three age groups were used for this study. Players from the U/16 and U/18 teams in the two schools were tested prior to the 2007 season. Players from the U/17, U/18 and U/19 club development teams were tested prior to the 2008 season. The combined total number of players in the teams amounted to 110 players. Method: The test battery consisted of a biomechanical evaluation, proprioceptive and plyometric testing and an injury history questionnaire. The Biomechanical evaluation was done according to the protocol compiled by Hattingh (2003). This evaluation was divided into five regions with a dysfunction score being given for each region. A single limb stance test was used to test proprioception. A Sergeant jump test was utilised using the wall mark method to test plyometric jumping height. A previous injury questionnaire was also completed on all players prior to testing. Test subjects from the schools were tested with the test battery prior to commencement of the 2007 season. The testing on the club teams was undertaken prior to the 2008 season. Injuries were recorded on the prescribed injury recording form by qualified Physiotherapists at weekly sports injury clinics at each of the involved schools and clubs. The coaching staff monitored exposure to training activities and match play on the prescribed recording forms. These training and match exposure hours were used, along with the recorded injuries for creating an epidemiological profile. Injuries were expressed as the amount of injuries per 1000 play hours. Logistical regression was done by using the test battery variables as independent variables and the variable injured/not injured as dependent variable (Statsoft, 2003). This analysis created prediction functions, determining which variables predict group membership of injured and non injured players. Results: There were 110 youth players involved in the research study from seven teams and four different age groups. There were two groups of U/16 players, an U/17 group, three U/18 groups and an U/19 group. The players were involved in a total of 7974 hours of exposure to training and match play during the seasons they were monitored. The average age of the players was 16.6 years. The majority of players were right limb dominant (83.6%) and 65.7% of players failed a single limb stance test. The mean jump height for both legs combined was 33.77cm, with mean heights of 22.60cm for dominant leg jump and 22.66cm for the non dominant leg. In the biomechanical evaluation of the lower leg and foot area, the average youth player presented with adaptation of toes, normal or flat medial foot arches, a normal or pronated rear foot in standing and lying and a normal or hypomobile mid-foot joint. Between 42.7% and 51.8% of players also presenting with decreased Achilles tendon suppleness and callusing of the transverse foot arch. The youth profile for the knee area indicated that the players presented with excessive tightness of the quadriceps muscles, normal patella tilt and squint, normal knee height, a normal Q-angle, a normal VMO: VL ratio and no previous injuries. This profile indicated very little dysfunction amongst youth players for the knee area. For the hip area, the youth profile was described as follows: There was shortening of hip external rotators, decreased Gluteal muscles length, normal hip internal rotation and no previous history of injury. Between 38.2% and 62.7% of players also exhibit shortened muscle length of the adductor and Iliopsoas muscles and decreased length of the ITB (Iliotibial Band). In the Lumbo-pelvic area there was an excessive anterior tilt of the pelvis with normal lumbar extension, side flexion, rotation and lumbar saggital view without presence of scoliosis. Between 58.18% and 65.45% of players presented with an abnormal coronal view and decreased lumbar flexion. Between 41.81% and 44.54% of players also presented with leg length, ASIS, PSIS, Cleft, Rami and sacral rhythm asymmetry. The similarity of the results for these tests in all players contributed to a new variable called 'SIJ dysfunction'. This was compiled from the average of the scores for Leg length, ASIS, PSIS, Cleft, Rami and Sacral rhythm, which was also considered for inclusion in the prediction model. The neurodynamic results of youth players indicated that approximately between 44.54% and 50.91% of players presented with decreased Straight leg raise and prone knee bend tests. The total combined dysfunction scores for the left and right sides were 17.091 and 17.909 respectively, indicating that there were higher levels of dysfunction on the right side than the left. This increased unilateral dysfunction could probably be attributed to limb dominance and increased use of the one leg for kicking and passing during the game. In the epidemiological study on youth players, there were a total of 49 training injuries and 52 match injuries. The total injury rate for youth players was 12.27 injuries/1000 hours, with a total match injury rate of 37.12 injuries/1000 match hours. The combined training injury rate was 7.17 injuries/1000 training hours. 87.13% of injuries were of the lower limb area and the individual areas with the highest percentage of injuries were the Ankle (25.74%), Knee (19.80%), Thigh (15.84%) and Lower leg (14.85%).The totals for youth players indicated that sprains (30.69% of total), strains (27.72% of total) and contusions (27.72% of total) were the most common causative mechanism of injuries. The severity of injuries show 'zero day' (no time off play) injuries to be the most common type (35.64%), followed by 'slight' (1 to 3 days off play) (33.66%) and 'minor' (4 to 7 days off play) (14.85%). School players had higher injury rates than club players but the severity of injuries to club players was higher, with longer absences from play. Non-contact injuries accounted for 52.47% of the total with 46.53% being contact injuries. School players had lower levels of non-contact injuries than club players, which correlated well with lower dysfunction scores recorded for school players during the biomechanical evaluations. This demonstrated that there was a definite relationship between levels of biomechanical dysfunction and the percentage of non-contact injuries in youth players, which formed the premise of the creation of a prediction model for non-contact youth soccer injuries. The next step in the creation of a prediction model was to identify the variables that discriminated maximally between injured and non-injured players. This was done using stepwise logistic regression analysis. After the analysis, ten variables with the largest odds ratios were selected for inclusion in the prediction model to predict non-contact injuries in youth soccer players. The prediction model created from the stepwise analysis presented as follows: P (injury)= exp(-8.2483 -1.2993a + 1.8418b + 0.2485c + 4.2850d + 1.3845e + 1.3004f-1.1566g + 1.8273h-0.9460i-0.5193j) l + exp(-8.2483-1.2993a + 1.8418b+ 0.2485c + 4.2850d + 1.3845e + 1.3004f-1.1566g + 1.8273h-0.94601-0.5193J) a = Toe dysfunction b = Previous ankle injury c = Ankle dysfunction d = SIJ dysfunction e = Lumbar Extension f = Straight Leg Raise g = Psoas length h = Patella squint i = Gluteal muscle length j = Lumbar dysfunction P = probability of non contact injury exp(x) = e x , with e the constant 2.7183 In the ankle area, the toe positional test, previous ankle injury history and combined ankle dysfunction score were included in the prediction model. In the knee area, the patella squint test was included in the model. In the hip area, the Psoas component of the Thomas test was included, along with the Gluteal muscle length test. In the Lumbo-pelvic area, the SIJ dysfunction (average of Leg length, ASIS, PSIS, Rami, Cleft and Sacral rhythm tests), lumbar extension test and lumbar dysfunction scores were included in the prediction model. In the neurodynamic area, the Straight leg raise test was included in the prediction model. The prediction model therefore contained tests from all five the bio mechanical areas of the body. Overall, this model correctly predicted 86.91% of players as either injured or not-injured. The I value (effect size index for improvement over chance) of the prediction model (1=0.67), along with the sensitivity (65.52%), specificity (94.87%), overall correct percentage of prediction (86.91%) and Hosmer and Lemeshow interferential goodness-to-fit value (X 2(8) = 0.7204), all demonstrated this prediction model to be a valid and accurate prediction tool for non-contact youth soccer injuries A second prediction model, for the prediction of hip and groin injuries amongst youth players, was also created. The prediction model created from the stepwise analysis for groin injuries presents as follows: P (Groin injury)^ exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) l + exp(-116.2 + 33.5383d+14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) d = SIJ dysfunction k = Previous knee injury m = Previous hip injury e = Lumbar extension f = Straight leg raise n = Limb dominance p = ND/Bil plyometric ratio P = probability of groin injury exp(x) = ex, with e the constant 2.7183 The prediction model for hip and groin injuries included the variables of SIJ dysfunction, previous knee injury, previous hip injury, lumbar extension, straight leg raise, limb dominance and the ratio of non-dominant leg to bilateral legs plyometric height. When all the validifying tests were examined, the I-value (0.64868), sensitivity (66.67%), specificity (98.01%), false negatives (1.98%), false positives (33.33%), Hosmer and Lemeshow goodness-to-fit value (X2(8) = 0.77) and the overall percentage of correct prediction (96.26%) all reflected that this model was an accurate prediction tool for hip and groin injuries amongst youth soccer players. Conclusion: This study showed that it was possible to create a prediction model for non-contact youth soccer injuries based on a pre-season biomechanical, plyometric and proprioceptive evaluation along with a previous injury history questionnaire. This model appears as follows: P (injury)= exp(-8.2483 -1.2993a + 1.8418b + 0.2485c + 4.2850d + 1.3845e + 1.3004f - 1.1566g + 1.8273h - 0.9460i - 0.5193J) l + exp(-8.2483-1.2993a+ 1.8418b + 0.2485c + 4.2850d + 1.3845e + 1.3004f-1.1566g+1.8273h-0.94601-0.5193J) a = Toe dysfunction b=Previous ankle injury c = Ankle dysfunction d= SIJ dysfunction e=Lumbar Extension f = Straight Leg Raise g = Psoas length h = Patella squint i = Gluteal muscle length j = Lumbar dysfunction P = probability of non contact injury exp(x) = ex, with e the constant 2.7183 It was also possible to create a prediction model for non contact hip and groin injuries, which appears as follows: P (Groin injury)= exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) l + exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) d = SIJ dysfunction k = Previous knee injury m = Previous hip injury e = Lumbar extension f = Straight leg raise n = Limb dominance p = ND/Bil plyo metric ratio P = probability of groin injury exp(x) = ex, with e the constant 2.7183 It was also possible to create a prediction model for non contact hip and groin injuries, which appears as follows: P (Groin injury)= exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) l + exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) d = SIJ dysfunction k = Previous knee injury m = Previous hip injury e = Lumbar extension f = Straight leg raise n = Limb dominance p = ND/Bil plyo metric ratio P = probability of groin injury exp(x) = ex, with e the constant 2.7183 Using the hip and groin prediction model, combined with the injury prediction model, injuries in youth soccer players can be predicted. The data for each player should first be substituted into the injury prediction model, to determine the chance of getting injured during the season. The data should then be substituted into the hip and groin injury prediction model, determining the chance of hip and groin injuries during the season. The results from the groin injury prediction model could then be used to exclude groin injuries amongst players. A negative result for the hip and groin injury, which showed a false negative percentage of 1.98%, could be used to determine that an injury that was predicted using the overall injury prediction model, would not be a hip and groin injury. A positive result in the groin injury test could, however, not exclude injuries to other body areas that were predicted by the overall injury prediction model, so the groin injury prediction model could only be used to exclude hip and groin injuries. / Thesis (Ph.D. (Education)--North-West University, Potchefstroom Campus, 2009.

Gastrulation, literally “formation of the gut” is ultimately an inadequate term to describe one of the most dynamic periods during vertebrate developmental biology. During gastrulation coordinated cell movements reshape the non-descript blastula into the structured gastrula and simultaneously specify the three germ layers: endoderm, mesoderm and ectoderm. The morphogenetic movements of gastrulation are highly conserved between species, but the links between their genetic and biomechanical regulation are poorly understood. The zebrafish embryo – externally hatched, optically clear and amenable to genetic manipulation – is an ideal vertebrate model in which to study both morphogenetic movements and their genetic control. This thesis provides a detailed analysis of the zebrafish Mix-type homeobox transcription factor, Mtx2, both in terms of its role in gastrulation and the molecular mechanisms regulated by Mtx2. This approach involved detailed examination of the Mtx2 loss-of-function phenotype and, subsequently, use of this phenotype as the basis for a microarray screen to identify and investigate Mtx2-dependent genes. One specific Mtx2-dependent gene, katanin-like 1 was investigated further by loss-of-function studies. Prior to this study the mtx2 gene was identified by homology, within its homeodomain, to other Mix-family transcription factors, but both its function and transcriptional targets remained unknown. Using a morpholino knockdown approach, this thesis demonstrates that Mtx2 is essential for vegetal movement (epiboly), but not specification, of the embryonic germ layers and extra-embryonic tissues during zebrafish gastrulation. The recruitment of filamentous actin (F-actin) to a punctate band at the blastoderm margin, was previously shown to be responsible for progression of epiboly. However, formation of this structure is demonstrated to be Mtx2-dependent. Microarray expression profiling of the Mtx2 loss-of-function phenotype was performed to screen for novel genes with roles in gastrulation. This approach identified Mtx2-dependent genes with roles in cytoskeletal dynamics, cell-cell adhesion and endocytosis and vesicular trafficking – processes known to be involved in morphogenetic movements. Many Mtx2-dependent genes are co-expressed with mtx2 in the extra-embryonic yolk syncytial layer (YSL), the teleost functional equivalent of mammalian visceral endoderm. The subset of Mtx2-dependent genes co-expressed with mtx2 and that contain Mtx2-binding sites within their 2kb proximal promoter represent the genes with the greatest likelihood of being direct Mtx2 transcriptional targets. A novel homologue of the microtubule severing protein Katanin, known as katanin-like 1 (katnal1) met all these conditions. Morpholino knockdown of Katnal1 demonstrates that like Mtx2, Katnal1 is essential for gastrulation in zebrafish. A cloned Katnal1mCherry fusion construct was observed to associate with microtubules, and demonstrated bi-directional trafficking around transfected mammalian cells. Analysis of the microtubule network in wild-type and morpholino injected zebrafish embryos demonstrated that remodelling of the extensive microtubule network found in the YSL and yolk cytoplasmic layer (YCL) is Katnal1-dependent. Nuclear division within the YSL and F-actin recruitment to the blastoderm margin are also Katnal1-dependent. This thesis therefore demonstrates, for the first time directly, the multiple, specific roles played by the microtubule network of the YSL/YCL. Katnal1 is highly conserved from Drosophila to mammals and is dynamically expressed during mouse gastrulation. The Mtx2 binding motif in the katnal1 2kb proximal promoter can be bound by both Mtx2 and its putative mouse homologue Mixl1. This suggests that katnal1 may also be a direct target of Mtx2. At the technical level, these results demonstrate the validity of screening for novel developmentally important genes using a zebrafish microarray-based approach, the potential of such an approach to, ab initio, identify a candidate list of transcription factor targets and confirm the utility of the zebrafish as a developmental model. At the biological level, this work collectively suggests that Mtx2 is a central regulator of the morphogenetic movement of epiboly and that Katnal1-dependent microtubule remodelling drives multiple aspects of gastrulation, potentially from Drosophila through to humans.

L'arthrose de la main est une pathologie qui engendre des douleurs et des impotences fonctionnelles fortement handicapantes pour la vie quotidienne. Malheureusement, du fait de la complexité biomécanique de la main et du manque de quantification des forces subies par les articulations des doigts, la prévention et la réhabilitation de cette pathologie demeurent problématiques. L'objectif de ce travail doctoral a été de développer une modélisation musculo-squelettique de la main pour améliorer la compréhension de l'arthrose du point de vue biomécanique. Un modèle complet de la main, incluant les cinq doigts et le poignet, ainsi qu'un protocole expérimental de mesure de la cinématique et des forces externes appliquées à la main ont d'abord été développés pour estimer l'ensemble des forces musculaires et des forces articulaires durant la préhension. Ces outils méthodologiques ont permis de clarifier les risques d'arthrose associés aux types de préhension ainsi que ceux spécifiques aux articulations. Afin d'analyser plus précisément les facteurs de risques associés à chaque individu, une méthode d'individualisation des paramètres musculaires a été développée afin de mettre le modèle de la main à l'échelle des capacités réelles des individus. Cette méthode a été employée pour l'analyse de deux patientes et a permis de caractériser les adaptations et les conséquences biomécaniques associées à leurs affections spécifiques. Le modèle de la main et les protocoles expérimentaux développés ont ainsi fournit des données quantifiées qui représentent un intérêt concret pour l'amélioration de la prévention ainsi que pour l'élaboration et l'évaluation de programmes de réhabilitation. / Hand osteoarthritis is a pathology which results in pain and functional impotencies which are problematic for everyday life. Unfortunately, because of the complexity of hand biomechanics and the lack of quantification of finger joint loadings, the prevention and the rehabilitation of this pathology remain problematic. The objective of this doctoral work was to develop the musculoskeletal modelling of the hand to improve the understanding of hand osteoarthritis from a biomechanical point of view. A complete model of the hand, including the five fingers and the wrist, as well as an experimental protocol for measuring hand kinematics and grip forces were first developed to estimate all the muscle forces and joint forces during prehension tasks. These methodological tools have then been used to clarify the risk factors of hand osteoarthritis associated to prehension tasks and to specific joints. To investigate more precisely the risk factors associated to individuals, a method has been developed to individualise muscle parameters of the hand musculoskeletal model in order to provide a better representation of the real performances of each subject. This method has then been applied to the analysis of two osteoarthritis patients and allowed a complete characterization of the specific biomechanical adaptations and consequences associated to their specific affections. The hand musculoskeletal model and the experimental protocols developed during this doctoral work provided quantified data which represents a concrete interest to improve prevention but also to elaborate and evaluate rehabilitation programs.

Made available in DSpace on 2016-06-02T19:22:06Z (GMT). No. of bitstreams: 1 3395.pdf: 2690333 bytes, checksum: 00f09a0b23fd204a83ebf1fa55f2b3ed (MD5) Previous issue date: 2010-10-08 / Financiadora de Estudos e Projetos / The aim of this study was to investigate the effects of lead on femurs and vertebrae during development and skeletal maturity of female rats. For this purpose, one month old female rats were treated with lead acetate 100mg/kg BW or saline 0,9% 0,1ml/100g BW . The treatment was administrated by gastric gavage, once a week, during two months. After the treatment period, the animals received only tap water and commercial chow ad libitum until they completed 6, 9 and 12 months of life. The 3 months old groups were sacrificed soon after the treatment. The incorporation of lead in bone tissue occurred in all groups of intoxicated animals. The lead did not interfere the body development of experimental animals. The lead intoxication induced reduced maximum load, stiffness and resilience of the femur in the threepoint bending test in the groups 6, 9 and 12 months of life. The compression test of vertebrae of contaminated rats showed reduction of biomechanical parameters only in skeletally mature rats (9 months). The present study revealed that lead exposure during early stage of development affected the bone mineral profile leading to biomechanical weakness with skeletal maturity. The results allow us to conclude that lead exposure affects the biomechanical properties of mature bone increasing susceptibility to fractures. / O objetivo deste trabalho foi investigar os efeitos do chumbo sobre fêmures e vértebras de ratas durante seu desenvolvimento e maturidade esquelética. Para este propósito, ratas com um mês de idade foram intoxicadas com acetato de chumbo 100mg/Kg de massa corporal, e os grupos controles tratados com salina 0,9% 0,1 ml/100g de massa corporal. O tratamento foi realizado via gavagem gástrica, uma vez por semana, durante 2 meses. Após este período, a contaminação foi cessada e os animais receberam apenas água e ração comercial ad libitum até completarem 6, 9 e 12 meses de vida, sendo os animais do grupo 3 meses eutanasiados ao final do tratamento. A incorporação do chumbo no tecido ósseo ocorreu em todos os grupos de animais intoxicados. O chumbo não prejudicou o desenvolvimento corporal dos animais experimentais. No teste de flexão a três pontos, foi observada a redução da força máxima, rigidez e resiliência dos fêmures dos animais contaminados dos grupos 6, 9 e 12 meses. Nas vértebras (teste de compressão), esta redução foi evidente em ratas maduras esqueléticamente (9 meses de idade). O presente estudo revelou que a exposição ao chumbo, durante o estágio inicial de desenvolvimento esquelético, afeta o perfil mineral ósseo levando ao enfraquecimento biomecânico com a maturidade esquelética. Os resultados nos levam a concluir que a exposição ao chumbo afeta as propriedades biomecânicas do osso maduro aumentando a predisposição à fraturas.

Submitted by Aneliza de Fatima Moraes da Silva null (aneliza_moraes@hotmail.com) on 2017-01-26T13:05:28Z No. of bitstreams: 1 OK FINAL - ANELIZA MORAES - DISSERTAÇÃO.pdf: 1506310 bytes, checksum: 9ff93a27f9c5ede3653d1720e5cf64c1 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-01-30T17:59:47Z (GMT) No. of bitstreams: 1 silva_afm_me_araca.pdf: 1506310 bytes, checksum: 9ff93a27f9c5ede3653d1720e5cf64c1 (MD5) / Made available in DSpace on 2017-01-30T17:59:47Z (GMT). No. of bitstreams: 1 silva_afm_me_araca.pdf: 1506310 bytes, checksum: 9ff93a27f9c5ede3653d1720e5cf64c1 (MD5) Previous issue date: 2016-12-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O consumo excessivo de bebidas alcoólicas pode ocasionar problemas econômicos, sociais e psicológicos, além de ser prejudicial a muitos órgãos e tecidos, incluindo o tecido ósseo. O álcool é um fator de desequilíbrio entre a formação e a reabsorção óssea, entre osteoblastos e osteoclastos. Este estudo teve como objetivo analisar os efeitos do consumo excessivo de álcool no tecido ósseo de ratos tratados com aguardente de cana de açúcar (cachaça), através da análise de fêmures e tíbias de ratos adultos-jovens. 24 ratos foram utilizados (Rattus norvegicus, albinus, Wistar), divididos em 4 grupos de 6 animais, separados aleatoriamente, sendo: – Grupo com 90 dias de tratamento, grupo controle (GC90) e grupo experimental (GE90); e grupo com 105 dias de tratamento, grupo controle (GC105) e grupo experimental (GE105). Após tratamento e eutanásia, os fêmures e tíbias foram submetidos as análises radiográficas, densitometria óssea e teste biomecânico, respectivamente, avaliados através do Sistema Digital Digora, DEXA (Dual-Energy X-ray Absorptiometry) e Ensaio mecânico. Os dados obtidos foram submetidos ao teste homocedasticidade com significância de 5% e realizada análise de variância – ANOVA- two-way e pós-teste Tukey. Os animais dos grupos controles apresentaram maior espessura óssea total e cortical, maior densidade óssea e conteúdo mineral ósseo (p<0,05), assim como maior resistência a fraturas comparados com os grupos experimentais. Ainda, observou-se que além do padrão de consumo os efeitos do etilismo sobre o tecido ósseo são influenciados pelo tempo de exposição ao álcool. Conclui-se, assim, que o consumo excessivo de aguardente de cana de açúcar além de ocasionar danos ao tecido ósseo, exerce efeito dose dependente nos parâmetros estudados em ratos adultos-jovens. / The excessive consumption of alcoholic beverages can cause economic, problems social and psychological, in addition to being harmful to many organs and tissues, including the bone tissue. Alcohol is a factor of an imbalance between the formation and bone resorption, between osteoblasts and osteoclasts. This study aimed to analyze the effects of excessive alcohol consumption in bone tissue of rats treated with Sugarcane brandy (Sugarcane liquor, aqua vitae), through examinations of femurs and tibias. Twenty-four animals were used (Rattus norvegicus, albinus, Wistar) were divided in 4 groups of 6 animals, randomly divided into: - Group with 90 days of treatment, control group (GC90) and experimental group (GE90); and group with 105 days of treatment, control group (GC105) and experimental group (GE105). After treatment and euthanasia, the femurs and tibias radiographic analyzes were submitted, bone densitometry and biomechanical test, respectively, evaluated by Digora Digital System, DEXA (Dual-Energy X-ray Absorptiometry) and mechanical testing. The data were submitted to the homoscedasticity test with 5% significance and performed analysis of variance - ANOVA- two-way and Tukey test. Control group animals showed higher total and cortical bone thickness, higher bone density and bone mineral content (p<0,05), as well as greater resistance to fractures comparad to the experimental groups. Furthermore, it was observed that in addition to the consumption pattern, the effects of alcohol on bone tissue are influenced by the time of exposure to alcohol. Concluded that the excessive consumption of Sugarcane brandy besides causing damage to the bone tissue exerts dose-dependent effect on the parameters studied in young adult rats.

O objetivo deste trabalho foi avaliar comparativamente a rigidez vertical, horizontal e de resistência à ruptura, com liberdade de movimentos em três eixos no espaço, de mandíbulas fixadas com sistemas 2,0-mm locking e convencionais com uma ou duas placas, em fraturas unilaterais no ângulo mandibular. Vinte mandíbulas de cordeiro, submetidas a osteotomia reproduzindo fraturas, foram divididas em três grupos: F1PC - placa convencional em linha oblíqua; F2PC - duas placas convencionais de modo monoplanar; FL - placa de sistema locking 2,0mm em linha oblíqua. Foi utilizada máquina de ensaio universal, onde foi acoplado suporte metálico com rodas para as mandíbulas. O sistema foi analisado em três diferentes momentos: pré-osteotomia com mandíbulas hígidas e pós-osteotomia/fixação e resistência à ruptura. Os valores de rigidez foram submetidos a análise de variância (p<0,005). Os valores de rigidez vertical (p< 0,0001), horizontal (p= 0,0005) e resistência a ruptura (p= 0,0001) entre pré e pósosteotomia/ fixação apresentaram uma diminuição significante. Na comparação entre os grupos, houve diferença significante para a rigidez vertical (p= 0,009) e o grupo F2PC apresentou maior rigidez. Na comparação entre os grupos, não houve diferença significante para a rigidez horizontal e para resistência a ruptura. Foi concluído que para rigidez vertical, horizontal e resistência a ruptura os valores de pós-osteotomia/fixação foram significantemente menores, o sistema de fixação com duas placas convencionais mostrou maior resistência quanto à rigidez vertical que os demais sistemas e não houve diferença estatisticamente significante na comparação entre os grupos quanto a rigidez horizontal e resistência a ruptura. / The objective of this work was to evaluate the vertical, horizontal and tensile rigidity with freedom of movement in three axes in space, of mandibles fixed with 2.0-mm locking and conventional systems with one or two plates, in unilateral fractures in the Angle of the mandible. Twenty mandibles of lamb, submitted to osteotomy and reproducing fractures, were divided into three groups: F1PC - conventional oblique line; F2PC - two conventional single-mode boards; FL - 2.0mm locking system plate in oblique line. A universal test machine was used, where metal support was coupled with wheels for the jaws. The system was analyzed in three different moments: pre-osteotomy with healthy mandibles and post-osteotomy / fixation and resistance to rupture. The stiffness values were submitted to analysis of variance (p <0.005). The values of vertical rigidity (p <0.0001), horizontal (p = 0.0005) and resistance to rupture (p = 0.0001) between pre and post osteotomy / fixation showed a significant decrease. In the comparison between the groups, there was a significant difference for vertical stiffness (p = 0.009) and the F2PC group presented greater stiffness. In the comparison between the groups, there was no significant difference for horizontal rigidity and for resistance to rupture. It was concluded that for post-osteotomy / fixation values were significantly lower for vertical, horizontal and tensile rigidity, the fixation system with two conventional plates showed greater resistance to vertical rigidity than the other systems and there was no statistically significant difference in comparison between the groups for horizontal rigidity and resistance to rupture.

Os efeitos ambientais negativos da urbanização podem ser mitigados pela presença de espaços verdes dentro e ao redor das cidades. Os elementos mais valiosos de tais áreas são reconhecidamente as árvores. Entretanto, existem também alguns riscos associados com a sua presença, os quais expressam a possibilidade de queda da árvore ou de seus galhos por perda de resistência biomecânica, resultando em perigo de morte e estragos a propriedades, bens e infraestrutura. Nesse sentido, a tomografia de impulso tem se mostrado como uma técnica bastante eficaz em detectar fragilidades biomecânicas no lenho. Considerando ainda que o vento é a principal força dinâmica atuante na copa das árvores, este estudo se propôs a (a) simular o comportamento dos ventos sobre a região do Parque Zoobotânico do Museu Paraense Emílio Goeldi, localizado em Belém-PA, durante quatro eventos de chuvas e ventos fortes usando o ENVI-met, (b) quantificar a perda de resistência biomecânica através da tomografia de impulso em 12 árvores presentes no referido parque e (c) identificar as árvores que possuem um maior risco de queda. Os modelos gerados pelo ENVI-met foram capazes de mostrar zonas de turbulência atuando sobre a copa das árvores tomografadas, e levando em conta a perda de resistência biomecânica, o Guajará foi identificado como apresentando o maior risco de queda entre todas as árvores estudadas. Concluiu-se que o ENVI-met prestou-se perfeitamente para a identificação de zonas de turbulência atuando na copa das árvores. Uma vez conhecidas essas turbulências e considerando a perda de resistência biomecânica acusada pela tomografia, ações de manejo pontuais podem ser propostas e executadas visando diminuir o risco de queda de árvores por ventos fortes em eventos futuros. / Negative environmental effects of urbanization can be mitigated by the presence of green spaces in and around cities. The most valuable elements of such green spaces are considered to be trees. Nonetheless, trees can pose some risks, which encompass the likelihood of mechanical failure of trunk or branches, causing injury to people or damaging buildings and properties. Accordingly, impulse tomography has proven to be a very effective technique in detecting biomechanical weaknesses in the wood. Considering wind as the main dynamic force acting on the tree crown, this study aimed to (a) simulate the behavior of winds over the region of the Goeldi Museum (located in Belém, Pará State, Brazil) during four events of heavy rain and strong winds using the ENVI-met software, (b) quantify the loss of biomechanical resistance for 12 trees located at the Museum and (c) identify trees with high possibility of failure. The models generated by ENVI-met were able to find areas of turbulence influencing the canopy of those trees. Together with the loss of biomechanical resistance, it was possible to identify the Guajará as having the greatest risk of failure among all the analyzed trees. It was concluded that ENVI-met represents a great tool in the identification of turbulence areas that influence trees. Once these areas are identified, and considering the loss of biomechanical resistance given by the impulse tomography, punctual management actions can be proposed and put into action for the sake of reducing risk of failure in future events of strong winds.

Este estudo apresenta uma análise, por meio do método não linear dos elementos finitos, de uma prótese parcial fixa de quatro elementos, tendo como pilares um dente natural, localizado na região do primeiro pré-molar inferior, e um implante osseointegrado, localizado na região do segundo molar inferior do mesmo hemiarco. Os modelos deste trabalho, foram criados a partir de radiografias periapicais da região posterior da mandíbula, foram digitalizadas e, posteriormente modificadas, dando origem aos modelos computacionais. Com auxílio do programa Ansys® simulou-se uma carga vertical de 175 N, distribuída ao longo dos retentores e pônticos desta prótese. Foram avaliadas três situações: Modelo 1: prótese fixa com conectores rígidos; Modelo 2: prótese fixa com um conector semi-rígido entre o primeiro pré-molar e o segundo pré-molar; Modelo 3: prótese fixa com um conector semi-rígido entre primeiro molar e segundo molar. Para simular os conectores semirígidos foram usados elementos de contato. A partir dos resultados obtidos, percebeu-se, em todos os modelos, que a região óssea que apresentou maior concentração de tensões foi a próximo da crista óssea mesial do implante, sendo os maiores níveis de tensões encontrados no Modelo 2 e os menores no modelo 3. Observou-se também, com relação ao implante, nos Modelos 1 e 3, altos níveis de tensões na região cervical-mesial, próximo da união retentor-pilar intermediário, já no Modelo 2 percebemos um grande aumento das tensões em toda região cervical. Constatou-se também, com relação aos conectores no Modelo 1, altos níveis de tensões entre os pônticos e entre o pôntico e o retentor sobre implante; no Modelo 2, os maiores níveis de tensões foram encontrados entre os molares e, no Modelo 3 os maiores níveis de tensões foram encontrados no conector semi-rígido. / The aim of this study was to analyze, through a non linear method of finite elements, a fixed partial denture of four elements, having natural teeth as an abutment located in the mandibular first pre-molar region and an osseointegrated implant located in the mandibular second molar region in the same hemi-arc, when a vertical load of 175N was applied and distributed over the retainer and pontic. Three situations were evaluated: Model 1: fixed denture with rigid connectors; Model 2: fixed denture with a semi-rigid connector between the first and second pre-molar; Model 3: fixed denture with a semi-rigid connector between first molar and second molar. From the results obtained from all models, the bone region that presented the highest stress concentration was close to the mesial region in the cortical bone of the implant. The highest stress levels were found in model 2 and the lowest in model 3. As regards the implant, in models 1 and 3, higher stress levels were also observed in the cervicalmesial region, close to the intermediate retainer abutment union. In model 2, a great increase of stress was observed in the entire cervical region. Moreover, with regard to the connectors, in model 1, there were high stress levels between the pontics and between the pontic and implant retainer; in model 2 the highest stress levels were found between the molars; and in model 3, the highest stress levels were found at the semi-rigid connector.

A fundamentação de métodos diagnósticos precoces na ortopedia de eqüinos é de extrema importância clínica, cirúrgica e econômica. O presente estudo teve como objetivo estudar a correlação da densidade mineral óssea do terceiro metacarpiano de eqüinos, obtida pelo método de absorciometria radiográfica, com a resistência dos mesmos quando submetidos a ensaios biomecânicos de compressão e flexão. Utilizaram-se trinta pares de osso terceiro metacarpiano de eqüinos adultos, os quais foram dissecados, radiografados, analisados pelo método de absorciometria radiográfica, submetidos ao estudo tomográfico e a ensaios biomecânicos. Através dos dados obtidos não se observou correlação significativa entre os valores de densidade óptica radiográfica e as propriedades biomecânicas do osso terceiro metacarpiano. Concluiu-se que não se pode inferir que os valores de densidade óssea obtidos pela absorciometria radiográfica do osso terceiro metacarpiano de um eqüino tenha correlação com a capacidade deste osso de absorver cargas de compressão e flexão. / The complete knowledge about non-invasive methods for early disgnostics in equine orthopedy is economicaly important. This experiment has studied the correlation between bone mineral density determined by radiographic absorptiometry and bone resistance of equine third metacarpal bone submitted to both compression and flexion testings. Thirty pairs of third metacarpal bone of adult horses were collected, dissected, radiographed, analysed by the radiographic absorptiometry technique, and submitted to tomographic study and biomechanical testings. The results have shown there is no significant correlation between radiographic bone density values and biomechanical properties of the third metacarpal bone. Therefore, it has been concluded bone mineral density of the third metacarpal bone determined by radiographic absorptiometry do not predict bone capacity to resist compression and flexion loads.

Em uma tentativa de melhor restabelecer a função normal do ligamento cruzado anterior (LCA), foi proposta a técnica de reconstrução do LCA com feixe duplo (FD). Entretanto, a superioridade desta técnica frente à técnica com feixe simples (FS) ainda não está claramente demonstrada no cenário clínico. O propósito do presente estudo foi avaliar e comparar a amplitude de rotação tibial, o máximo de rotação interna e externa, e a força de reação ao solo de joelhos submetidos à reconstrução anatômica com feixe duplo, a joelhos submetidos à reconstrução com feixe simples, durante a realização de tarefas dinâmicas. Para isso, um total de 75 (setenta e cinco) indivíduos foram avaliados (26 reconstruções feixe duplo, 22 reconstruções feixe simples, 27 indivíduos sem lesão do LCA que formaram um grupo controle). Utilizando um sistema de análise do movimento humano, constituído por 4 câmeras para a análise do movimento, os indivíduos foram avaliados em três tarefas de demandas distintas. Utilizou-se a técnica TSACCAST para o cálculo da rotação interna e externa da tíbia. A média da amplitude de rotação tibial, máximo de rotação interna e externa, foi avaliada para cada joelho em cada um dos três grupos. A avaliação clínica destes pacientes foi realizada utilizando-se questionários subjetivo e objetivo (IKDC), assim como artrometria manual. Estas avaliações revelaram que ambos os grupos operados eram semelhantes no que se refere ao resultado clínico pós-operatório. A avaliação da amplitude de rotação tibial, máximo de rotação interna e externa, demonstrou que o joelho operado era semelhante ao joelho não operado e aos joelhos do grupo controle. Também não se verificou diferença significativa nos valores de amplitude de rotação tibial, máximo de rotação interna e externa, quando se comparou o grupo FS ao grupo FD. Desta forma, concluímos que a reconstrução do LCA com a técnica de FS e com a técnica de FD são similares no que se refere ao restabelecimento do controle da rotação da tíbia / In an attempt to better restore the normal function of the two ACL bundles, the ACL reconstruction with two bundles has been proposed. However, the superiority of the double-bundle technique has not been clearly demonstrated in the clinical setting. The purpose of this study was to compare the tibial rotational range, maximal internal and external rotation and ground reaction force of anatomical double-bundle anterior cruciate ligament reconstructed knees with single-bundle anterior cruciate ligament reconstructed knees during three different demanding tasks. A total of 75 subjects, (26 with double-bundle anterior cruciate ligament reconstruction, 22 with single-bundle anterior cruciate ligament reconstruction, and 27 healthy control individuals) were evaluated in this study. Using a 4-camera motion analysis system, motion subjects were recorded performing during three different tasks. Using the CAST technique, the internal-external tibial rotation of both knees was calculated. The mean tibial rotational range, maximum internal and external rotation, for each knee, was evaluated for the 3 groups (double-bundle group, single-bundle group, and control group). Clinical assessment, including objective and subjective IKDC scores, and knee arthrometric measurement, revealed restoration of the reconstructed knee stability with no differences between the two anterior cruciate ligament reconstruction groups. The results demonstrated that both groups resulted in tibial rotation range values that were similar to those in the non-injured knees and those in the healthy controls. There were also no significant differences in tibial rotational range, maximal internal and external rotation and ground reaction force between the DB group and the SB group. Therefore, anatomical double-bundle and single-bundle reconstruction are able to restore normal tibial rotation