En nuevo enfoque en el manejo de la marcha agazapada: laboratorio de análisis de la marcha, Hospital Ortopédico Infantil / New approach in the management of the crouch gait: at gait lab, Hospital Ortopédico Infantil

La marcha agazapada es una de las alteraciones más frecuentes en los pacientes con parálisis cerebral infantil, y aunque es fácilmente reconocible, tampoco ha sido claramente definida. En ella, la rodilla carece de una extensión dinámica, durante la fase de apoyo, el tobillo lo podemos encontrar en flexión plantar, dorsal o neutro, y las caderas generalmente están flexionadas y frecuentemente en rotación interna y en aducción. El presente es un estudio prospectivo, realizado en el Hospital Ortopédico Infantil, empleando los datos obtenidos del departamento de historias médicas y del laboratorio de análisis de la marcha, en el cual hemos utilizado la nueva clasificación cinemática de Michael Schwartz, Director de Bioingeniería del Laboratorio de Análisis de la Marcha del Gillette Children´s Hospital, Saint Paul, Minnesota, para sujetos que presentaban excesiva flexión de rodilla al contacto inicial. Con lo cual se obtiene 5 subtipos cinemáticas de marcha agazapada, de acuerdo a los datos obtenidos en el plano sagital, y que a la vez nos permiten saber a qué nivel se encuentran las alteraciones principales de los pacientes, proporcionándonos de esta manera una guía que nos ayude en la decisión del tratamiento a emplear y al mismo tiempo nos permite realizar una valoración post-quirúrgica

Crouch gait is one of the most frequent alterations in patients with cerebral palsy, and although it is easily recognizable, has not been clearly defined. In it, the knee lacks a dynamic extension during the stance phase, the ankle can be found in plantar flexion, dorsal or neutral, and hips are usually bent and often in internal rotation and adduction. This is a prospective study conducted at the Children's Orthopedic Hospital, using data obtained from the department of medical and gait laboratory, which we have used the new classification Schwartz Michaels kinematics, Director of Bioengineering, Laboratory of Analysis of the March of Gillette Children's Hospital, Saint Paul, Minnesota, for subjects with excessive knee flexion initial contact. Thus obtained five subtypes kinematic crouched running, according to data obtained in the sagittal plane and at the same time let us know at what level are the main changes of the patients, thereby providing a guide help us in deciding the treatment to be applied at the same time allows us to perform a post-surgical evaluation

Estudo comparativo do torque de remoção dos parafusos de conexão de pilares protéticos sobre implantes com conexão de hexágono interno e Cone Morse após ensaio de ciclagem mecânica / Comparative study of removal torque screw connection prosthetic pillars over implants connection hexagon internal Morse taper after mechanical cycling tests

Objetivo - Avaliar e comparar o torque de afrouxamento de munhões retos de duas peças conectados a implantes com conexão de hexágono interno (Grupo 1) e de pilares sólidos retos conectados a implantes de Cone Morse (Grupo 2), após ensaio de ciclagem mecânica. Método - Foram testados 10 conjuntos de cada grupo. Para a realização dos ensaios de ciclagem mecânica, os pilares de conexão Morse foram apertados com torque de 25 Ncm, e os pilares de conexão HI foram apertados com torque de 32 Ncm, com o torquimetro analógico, sendo que todos os pilares foram reapertados após 10 minutos. As amostras foram submetidas aos testes de fadiga a 360.000 ciclos, com carga axial aplicada de 80 N e frequência de 4 Hz. Após o término dos ciclos, o torque necessário para o afrouxamento dos componentes protéticos de cada grupo foi aferido, através de torquímetro analógico. Resultados - Os resultados demonstraram que diante das condições experimentais deste estudo houve diferença significativa nos valores de destorque entre os Grupos 1 e 2; e que a média de destorque do Grupo 1 foi de 61,98% e do Grupo 2 foi de 102,87%, sendo possível afirmar que o destorque dos implantes Cone Morse após a ciclagem é maior do que nos implantes de hexágono interno. Conclusões - Os resultados encontrados para as amostras do Grupo 2 mostraram que houve um aumento expressivo nos valores de destorque quando comparado aos valores iniciais de torque de apertamento, demonstrando uma melhora significativa no desempenho, após a ciclagem mecânica.

Objective - This study aimed to evaluate and compare the loosening torque of two-piece straight abutments connected to implant connection with internal hexagon (Group 1) and connected to solid pillars straight Morse taper implants (Group 2) after mechanical cycling test. Method - Were tested 10 sets of each group. For the testing of mechanical cycling, the pillars were fastened Morse connection with a torque of 25 Ncm, and the pillars of HI were tight connection with a torque of 32 Ncm using a analog torque meter, and all the pillars had been tightened after 10 minutes. The samples were subjected to fatigue testing to 360,000 cycles, with an axial load of 80 N applied andfrequency of 4 Hz upon completion of the cycles, the torque required for loosening of prosthetic components of each group was measured by means of analog torque meter. Results - Results showed that the experimental conditions before this study there were significant differences in values removal torque between Groups 1 and 2, and the average removal torque Group 1 was 61.98% and Group 2 was 102.87%, being possible to say that removal torque morse taper implant after cycling is greater than in internal hexagon implants. Conclusions - The results for samples from Group 2 showed that there was a significant increase in the values removal torque compared to baseline torque tightness, showing a significant improvement in performance after mechanical cycling.

Análise biomecânica ex vivo de um modelo de haste intramedular de polipropileno para osteossíntese em úmeros de bezerros / Ex vivo biomechanics assay of a model of polypropylene intramedullary nail for calf humeral osteosynthesis

Foram utilizados 12 pares de úmeros obtidos de bezerros machos da raça Holandesa, com idades entre 15 e 30 dias. Os úmeros esquerdos foram mantidos íntegros, e os direitos foram fraturados de forma oblíqua em sua diáfise, na transição entre os terços médio e proximal. A redução da fratura foi feita pela aplicação intramedular de haste de polipropileno, bloqueada por dois parafusos corticais de aço inoxidável, dispostos transversalmente em cada fragmento ósseo. Seis pares de ossos foram submetidos ao teste de compressão, e seis ao teste de flexão, utilizando-se uma máquina universal de ensaios. Nos testes de compressão, as cargas médias de ruptura foram 738,3N e 473,3N, e nos testes de flexão 322,4N e 117,9N, para os ossos íntegros e fraturados, respectivamente. Comparando-se o grupo de ossos fraturados com o grupo de ossos íntegros, verificou-se que o sistema proposto foi capaz de resistir a 66,4 por cento das cargas médias quando submetido à compressão, e a 36,6 por cento quando submetido à flexão. Úmeros fraturados e tratados com haste intramedular de polipropileno apresentaram resistência limitada se comparados aos ossos íntegros.

A total of 12 pairs of humeri from male calves 15 to 30 days old were used. The left humeri remained unchanged and the right ones were fractured in the diaphysis between proximal and middle thirds. The fracture was fixed with a polypropylene intramedullary nail interlocked with two steel bone screws crossed along each segment. Six pairs of bones were subjected to a compression test and the others to a flexural test using a universal testing machine. In the compression tests, the mean rupture loads were 738,3N and 473,3N, and in the flexural tests they were 322,4N and 117,9N for the intact and fractured bones respectively. Fractured bones fixed with the proposed model were able to resist 66.4 percent of the load during compression and 36.6 percent during bending when in comparison to intact bones. Fractured humeri treated with polypropylene intramedullary nail showed limited resistance compared to intact ones.

Força de reação do solo durante a marcha de crianças em ambiente aquático / Ground reaction force during childrens' gait in an aquatic environment

O objetivo desta pesquisa foi analisar parâmetros biomecânicos da marcha de crianças de 7 a 12 anos em ambiente aquático. Analisaram-se características dinamométricas, a fim de verificar o comportamento das mesmas no ambiente mais utilizado para a educação da marcha de indivíduos com as mais diversas patologias. Para a realização do estudo foram utilizadas plataformas de força subaquáticas para aquisição da componente vertical da força de reação do solo (FRS). Após as coletas de dados, as informações dinamométricas foram armazenadas e processadas pelo programa SAD32®, versão 3.0. Foi realizada estatística descritiva para os resultados encontrados. Há uma redução de até 62% da carga corporal da criança em relação ao ambiente terrestre. Sugere-se um aprofundamento nos dados encontrados e o estudo de outras variáveis que também influenciam na marcha subaquática, para que a vida de crianças que necessitam de recuperação funcional possa ser melhorada.

Aspectos singulares no tratamento ortodôntico do mesiodens / Uncommon aspects in the mesiodens orthodontic treatment

Os dentes supranumerários são aqueles que excedem o número normal nas dentaduras decídua e permanente, e resultam, provavelmente, da proliferação contínua da lâmina dentária. Essa anomalia de número tem predileção pelo gênero masculino, na proporção de 2:1. Na dentadura permanente, o supranumerário mais frequente ocorre entre os incisivos centrais superiores, sendo denominado mesiodens. O diagnóstico é confirmado por meio de exame radiográfico e o tratamento ideal é a extração, quando possível, em fase precoce, para a prevenção de alterações na oclusão dentária estética do sorriso. O presente trabalho apresenta o tratamento ortodôntico de um paciente com mesiodens e má oclusão de Classe II, por meio da extração dos pré-molares superiores, do mesiodens e aplicação de biomecânica diferenciada. Resultado final satisfatório foi obtido e mantido na fase de contenção.

Electromyographic evaluation of mandibular biomechanic / Evaluación electromiográfica de la biomecánica mandibular

The study of the craniomandibular biomechanics is related to the system of predominant lever and of the relation between function and mechanically induced deformations. This study has the purpose of evaluating the chewing muscular dynamics in the surface electromyography. Seventeen people of both sex, medium aged about 25, were selected, white skin and presenting Class I of Angle without apparent sign and symptom. The electromiographic data were obtained bilaterally from the masseter muscles, anterior temporal portion at the rest position and isometric position. Medtrace® passive bipolar surface electrodes were used coppled to a pre-amplifier, forming a circuit corresponding to a differential circuit. The registrations of the electric signals were caught by EMG- 800C equipment of Brazil EMG System Ltda with eigth channels, sample frequency of 2 KH and 16 bits resolution, digital filter with a band pass of 20-500 Hz. A comparison was through "t" Student or a Man- Whitney test according to the normality or not of the distribution, respectively. The results have shown important differences between the tasks but without sexual dimorphism. All these results indicate to the electrical activity of the temporal muscle in its anterior portion was bigger than the masseter muscle in rest position and the masseter muscle presented a higher potential of action than the anterior temporal muscle in isometric.

El estudio de la biomecánica craneomandibular se relaciona con el sistema de palanca predominante y la relación entre la función y deformaciones mecánicamente inducidas. Este estudio tuvo el propósito de evaluar la dinámica muscular de la masticación en la superficie electromiográfica en 17 personas de ambos sexos, con edad media de 25 años, de piel blanca y que presentaban clase I de Angle, sin aparentes signos y síntomas. Los datos electromiográficos fueron obtenidos bilateralmente desde los músculos maseteros, la porción anterior del músculo temporal en posición de descanso y en posición isométrica. Electrodos bipolares de superficie pasiva Medtrace ® fueron utilizados acoplados a un pre-amplificador, formando un circuito que corresponde a un circuito diferencial. Los registros de las señales eléctricas fueron capturados por el equipo EMG- 800C de Brazil EMG System Ltda. con 8 canales, frecuencia de muestreo de 2 KH y 16 bits de resolución, un filtro digital con una banda de paso de 20-500 Hz. La comparación fue hecha mediante "t" Student o la prueba Man-Whitney de acuerdo con la normalidad o no, de la distribución, respectivamente. Los resultados mostraron importantes diferencias entre las tareas realizadas, pero sin dimorfismo sexual. Todos estos resultados muestran a la actividad eléctrica del músculo temporal en su porción anterior, mayor que el músculo masetero en posición de reposo, y que el músculo masetero presenta un mayor potencial de acción que la parte anterior del músculo temporal en posición isométrica.

Caracterização de uma haste femoral de Ti-6Al-4V não cimentada / Characterization of a cementless Ti-6Al-4V femoral stem

O objetivo deste estudo foi determinar a viabilidade de produção de uma prótese femoral de titânio garantindo a qualidade da matéria prima e as características das superfícies. Um protótipo foi criado pelo Método de Elementos Finitos em AutoCad® 2000. A simulação dos esforços demonstrou uma tensão de von Mises 8,1 vezes menor que a tensão crítica para escoamento do material. Na determinação dos constituintes metálicos, obteve-se: Fe  =   0,06%, Al  = 6,20%, V  = 3,57%, O  = 0,115%, N  = 0,003%, H  = 0,010%, e ausência de metais pesados. As propriedades elasto-plásticas da amostra tiveram valor médio de dureza de 4,45 (3,92 a 4,79) GPa e o módulo de elasticidade variou de 112,12 a 140,77  GPa (média  = 134,33). O coeficiente de rugosidade médio (DP) no cone foi de 0,60  (0,03) μm; na região jateada de 12,2 (0,8) μm e na ponta de 0,41 (0,01) μm. Nos ensaios de fadiga e de corrosão não foram observadas alterações. A análisegranulométrica do pó do material depositado demonstrou predominância de partículas médias (75  μm a 180  μm; 84%). A espessura da camada do material depositado apresentou valor médio de 52,7  μm (0 a 318  μm), porosidade média de 16% (variandode 3% a 41%), poros de diâmetro médio de 88,5  μm e profundidade média de 28,2  μm. A tensão (força por unidade de área) de adesão da camada porosa depositada revelou valoresde 15 a 17  MPa. Em conclusão, os resultados dos testes e ensaios técnicos estão dentro das normas internacionalmente recomendadas e padronizadas para implantes metálicos em titânio estando essa prótese de acordo com os padrões internacionaisde qualidade e segurança.

The objective of this work was to study the feasibility of manufacturing a cementless femoral prosthesis in Brazil, in compliance with internationalstandards of quality assurance. A virtual prototype by the Finite Elements Model in AutoCad® 2000 was assessed and demonstrated a von Mises tension 8.1 below the deformation point. In determining the metallic components, the percentages were Fe  = 0.06%, Al  = 6.20%, V  = 3.57%, O  = 0.115%, N  = 0.003%, H  = 0.010% without any contamination due to heavy metals. The elasto-plastic properties showed an average value of hardness of 4.45 (3.92 to 4.79) GPa and elasticity module varied from 112.12 to 140.77  GPa (mean  = 134.33). The average coefficient of roughness (SD) in the cone was 0.60 (0.03) μm, 12.2 (0.8) μm in the plasma spray coating region, and 0.41 (0.01) μm in the tip. In the assays for fatigue and corrosion no changes were observed. The grain size analysis of the deposited material dust demonstrated predominantly (84%) medium size particles (75  μm to 180  μm). The thickness of the deposited material layer presented average value of 52.7  μm (0 to 318  μm), average porosity of 16% (varying from 3% to 41%) and pores of average diameterof 88.5  μm and average depth of 28.2  μm. The force of adhesion of the deposited porous layer showed values between 15  and  17  MPa. Results were in accordance with the norms and tests internationally recommended and standardized for metallic implants in titanium alloy and  the femoral prosthesis manufactured with national technology was in accordance with international standards of design, quality and safeness.

A comparison of single-versus double-row suture anchor techniques in a simulated repair of the rotator cuff: an experimental study in rabbits.

We compared time-dependent changes in the biomechanical properties of single-and double-row repair of a simulated acute tear of the rotator cuff in rabbits to determine the effect of the fixation techniques on the healing process. A tear of the supraspinatus tendon was created in 80 rabbits which were separated into two equal groups. A single-row repair with two suture anchors was conducted in group 1 and a double-row repair with four suture anchors in group 2. A total of ten intact contralateral shoulder joints was used as a control group. Biomechanical testing was performed immediately post-operatively and at four and eight weeks, and histological analysis at four and eight weeks. The mean load to failure in group 2 animals was greater than in group 1, but both groups remained lower than the control group at all intervals. Histological analysis showed similar healing properties at four and eight weeks in both groups, but a significantly larger number of healed tendon-bone interfaces were identified in group 2 than in group 1 at eight weeks (p < 0.012). The ultimate load to failure increased with the number of suture anchors used immediately post-operatively, and at four and eight weeks. The increased load to failure at eight weeks seemed to be related to the increase in the surface area of healed tendon-to-bone in the double-row repair group.

Upper-limb kinematics and coordination of short grip and classic drives in field hockey.

The aim of this study was to compare the upper-limb kinematics and coordination of the short grip and classic drives in field hockey. Ten elite female players participated in the experiment. The VICON system was used to record the displacement of markers placed on the stick and the players' joints during five short grip and five classic drives. Kinematic and coordination parameters were analyzed. The ball's velocity was recorded by a radar device that also served as the drive target. Kinematic differences were noted between the two drive conditions, with shorter duration and smaller overall amplitude in the short grip drive, explained by the shorter lever arm and the specific context in which it is used. No differences were noted for upper-limb coordination. In both types of stick holding, an interlimb dissociation was noted on the left side, whereas the right interlimb coordination was in phase. Moreover, the time lag increased in the disto-proximal direction, suggesting wrist uncocking before impact and the initiation of descent motion by the left shoulder. Mediolateral analysis confirmed these results: coordination of left-right limbs converged at the wrist but dissociated with more proximal joints (elbows and shoulders).

Comparison between kinematic and kinetic methods for computing the vertical displacement of the center of mass during human hopping at different frequencies.

Kinematic and kinetic methods (sacral marker, reconstructed pelvis, segmental analysis, and force platform methods) have been used to calculate the vertical excursion of the center of mass (COM) during movement. In this study we compared the measurement of vertical COM displacement yielded by different methods during able-bodied subjects' hopping at different frequencies (varying between 1.2 and 3.2 Hz). ANOVA revealed a significant interaction between hopping frequency and method (p < 0.001), showing that increasing hopping frequency reduced the differences between methods. A post hoc analysis revealed a significant difference between all methods at the lowest hopping frequency and between the force platform and both the sacral marker and reconstructed pelvis methods at the intermediate hopping frequencies, with differences ranging from 16 to 67 millimeters (all p < 0.05). Results are discussed in view of each methods' limits. We conclude that the segmental analysis and force platform methods can be considered to provide the most accurate results for COM vertical excursion during human hopping in a large range of hopping frequency.

Finite element analysis of head-neck kinematics under simulated rear impact at different accelerations.

The information on the variation of ligament strains over time after rear impact has been seldom investigated. In the current study, a detailed three-dimensional C0-C7 finite element model of the whole head-neck complex developed previously was modified to include T1 vertebra. Rear impact of half sine-pulses with peak values of 3.5g, 5g, 6.5g and 8g respectively were applied to the inferior surface of the T1 vertebral body to validate the simulated variations of the intervertebral segmental rotations and to investigate the ligament tensions of the cervical spine under different levels of accelerations. The simulated kinematics of the head-neck complex showed relatively good agreement with the experimental data with most of the predicted peak values falling within one standard deviation of the experimental data. Under rear impact, the whole C0-T1 structure formed an S-shaped curvature with flexion at the upper levels and extension at the lower levels at early stage after impact, during which the lower cervical levels might experience hyperextensions. The predicted high resultant strain of the capsular ligaments, even at low impact acceleration compared with other ligament groups, suggests their susceptibility to injury. The peak impact acceleration has a significant effect on the potential injury of ligaments. Under higher accelerations, most ligaments will reach failure strain in a much shorter time immediately after impact.

An instance-based algorithm with auxiliary similarity information for the estimation of gait kinematics from wearable sensors.

Wearable human movement measurement systems are increasingly popular as a means of capturing human movement data in real-world situations. Previous work has attempted to estimate segment kinematics during walking from foot acceleration and angular velocity data. In this paper, we propose a novel neural network [GRNN with Auxiliary Similarity Information (GASI)] that estimates joint kinematics by taking account of proximity and gait trajectory slope information through adaptive weighting. Furthermore, multiple kernel bandwidth parameters are used that can adapt to the local data density. To demonstrate the value of the GASI algorithm, hip, knee, and ankle joint motions are estimated from acceleration and angular velocity data for the foot and shank, collected using commercially available wearable sensors. Reference hip, knee, and ankle kinematic data were obtained using externally mounted reflective markers and infrared cameras for subjects while they walked at different speeds. The results provide further evidence that a neural net approach to the estimation of joint kinematics is feasible and shows promise, but other practical issues must be addressed before this approach is mature enough for clinical implementation. Furthermore, they demonstrate the utility of the new GASI algorithm for making estimates from continuous periodic data that include noise and a significant level of variability.

Assessment of finger forces and wrist torques for functional grasp using new multichannel textile neuroprostheses.

New multichannel textile neuroprotheses were developed, which comprise multiple sets of transcutaneous electrode arrays and connecting wires embroidered into a fabric layer. The electrode arrays were placed on the forearm above the extrinsic finger flexors and extensors. Activation regions for selective finger flexion and wrist extension were configured by switching a subset of the array elements between cathode, anode, and off states. We present a new isometric measurement system for the assessment of finger forces and wrist torques generated using the new neuroprostheses. Finger forces (from the middle phalanxes) were recorded using five load cells mounted on a "grasp handle" that can be arbitrarily positioned in space. The hand and the grasp handle were rigidly mounted to a 6-degree of freedom load cell, and the forces and torques about the wrist were recorded. A vacuum cushion was used to comfortably fixate the forearm. The position and orientation of the forearm, wrist, fingers, and handle were recorded using a new three-dimensional position measurement system (accuracy <+/-1 mm). The measurement system was integrated into the real-time multichannel transcutaneous electrode environment, which is able to control the spatiotemporal position of multiple activation regions. Using the combined system and textile neuroprosthesis, we were able to optimize the activation regions to produce selective finger and wrist articulation, enabling improved functional grasp.

Constellation of phase singularities in a speckle-like pattern for optical vortex metrology applied to biological kinematic analysis.

A novel technique for biological kinematic analysis is proposed that makes use of the pseudophase singularities in a complex signal generated from a speckle-like pattern. In addition to the information about the locations and the anisotropic core structures of the pseudophase singularities, we also detect the spatial structures of a cluster of phase singularities, which serves as a unique constellation characterizing the mutual position relation between the individual pseudophase singularities. Experimental results of in vivo measurements for a swimming fish along with its kinematic analysis are presented, which demonstrate the validity of the proposed technique.

Quantitative mechanical evaluation and analysis of Drosophila embryos through the stages of embryogenesis.

The fruit fly Drosophila embryo is one of the most important model organisms in genetics and developmental biology research. To better understand the biomechanical properties involved in Drosophila embryo research, this work presents a mechanical characterization of living Drosophila embryos through the stages of embryogenesis. Measurements of the mechanical forces of Drosophila embryos are implemented using a novel, in situ, and minimally invasive force sensing tool with a resolution in the range of microN. The measurements offer an essential understanding of penetration force profiles during the microinjection of Drosophila embryos. Sequentially quantitative evaluation and analysis of the mechanical properties, such as Young's modulus, stiffness, and mechanical impedance of living Drosophila embryos are performed by extracting the force measurements throughout the stages of embryogenesis. Experimental results illustrate the changing mechanical properties of Drosophila embryos during development, and thus mathematical models are proposed. The evaluation provides a critical step toward better understanding of the biomechanical properties of Drosophila embryos during embryogenesis, and could contribute to more efficient and significant genetic and embryonic development research on Drosophila.

Injury biomechanics and child abuse.

Child abuse is a leading cause of morbidity and mortality in young children and infants in the United States. Medical care providers, social services, and legal systems make critical decisions regarding injury and history plausibility daily. Injury plausibility judgments rely on evidence-based medicine, individualized experiences, and empirical data. A poor outcome may result if abuse is missed or an innocent family is accused, therefore evidence and science-based injury assessments are required. Although research in biomechanics has improved clinical understanding of injuries in children, much work is still required to develop a more scientific, rigorous approach to assessing injury causation. This article reviews key issues in child abuse and how injury biomechanics research may help improve accuracy in differentiating abuse from accidental events. Case-based biomechanical investigations, human surrogate, and computer modeling biomechanics research applied to child abuse injury are discussed. The goal of this paper is to provide an overview of key research studies rather than on review or commentary articles. Limitations and future research needs are also reviewed.

X-ray kinematography of phase transformations of three-component lipid mixtures: a time-resolved synchrotron X-ray scattering study using the pressure-jump relaxation technique.

By using the pressure-jump relaxation technique in combination with time-resolved synchrotron small-angle X-ray diffraction (TRSAXS), the kinetics of lipid phase transformations of ternary lipid mixtures serving as model systems of heterogeneous raftlike membranes were investigated. To this end, we first established the temperature-pressure phase diagram of a model lipid raft mixture, 1,2-dioleoyl- sn-glycero-3-phosphatidylcholine (DOPC)/1,2-dipalmitoyl- sn-glycero-3-phosphatidylcholine (DPPC)/cholesterol (1:2:1), using Fourier transform infrared spectroscopy and SAXS, covering the pressure range from 1 bar to 10 kbar at temperatures in the range from 7 to 80 degrees C. We then studied the kinetics of interlamellar phase transitions of the ternary lipid system involving transitions from the fluidlike (liquid-disordered, l d) phase to the liquid-ordered (l o)/liquid-disordered (l d) two-phase coexistence region as well as between the two- and three-phase coexistence regions of the system, where also solid-ordered phases (s o) are involved. The phase transition from the all-fluid l d phase to the l o+l d two-phase coexistence region turns out to be rather rapid. Phases appear or disappear within the 25 ms time resolution of the technique, followed by a slow lattice relaxation process, which, depending on the pressure-jump amplitude, takes several seconds. Contrary to many one-component phospholipid phase transitions, the kinetics of the l d <--> l o+l d transition follows a similar time scale and mechanism for the pressurization and depressurization direction. A similar behavior is observed for the phase transition kinetics of the s o+l o+l d <--> l o+l d transformation and even for the s o+l o+l d <--> l d transformation, jumping across the l o+l d two-phase region. All transitions are fully reversible, and no intermediate states are populated. As indicated by the complex relaxation profiles observed, the overall rates observed seem to reflect the effect of coupling of various dynamical processes through the transformation, involving fast conformational changes in the sub-millisecond time regime and slow relaxation of the lattices growing, probably being largely controlled by the transport and redistribution of water into and in the new phases of the multilamellar vesicle assemblies.

[Improved care of foot ulcer using foot pressure measurement and foot care method sheet].

At this sanatorium, the number of foot bottom ulcer patients was 13 and the tenure of the foot bottom ulcer was average 11 years. According to the treatment that was not unified, we thought about the cause of the prolongation. Therefore, we made evaluation and care method sheet ("foot care sheet") of the ulcer for the unification. We used the foot pressure measurement system (F-scan) to 4 patients for the pressure dispersion of the ulcer. We devised the protection law of the ulcer, and an ulcer did not require pressure more than 5 kilos/cm2. We recorded the size of the ulcer, weight of the liquid from ulcer, a photograph to care sheet once a week. I performed ulcer protection law and management with the foot care sheet to 4 patients for average 4 months. As a result, the ulcers of 3 patients out of 4 patients became small.

Three-dimensional mathematical model for deformation of human fasciae in manual therapy.

CONTEXT: Although mathematical models have been developed for the bony movement occurring during chiropractic manipulation, such models are not available for soft tissue motion. OBJECTIVE: To develop a three-dimensional mathematical model for exploring the relationship between mechanical forces and deformation of human fasciae in manual therapy using a finite deformation theory. METHODS: The predicted stresses required to produce plastic deformation were evaluated for a volunteer subject's fascia lata, plantar fascia, and superficial nasal fascia. These stresses were then compared with previous experimental findings for plastic deformation in dense connective tissues. Using the three-dimensional mathematical model, the authors determined the changing amounts of compression and shear produced in fascial tissue during 20 seconds of manual therapy. RESULTS: The three-dimensional model's equations revealed that very large forces, outside the normal physiologic range, are required to produce even 1% compression and 1% shear in fascia lata and plantar fascia. Such large forces are not required to produce substantial compression and shear in superficial nasal fascia, however. CONCLUSION: The palpable sensations of tissue release that are often reported by osteopathic physicians and other manual therapists cannot be due to deformations produced in the firm tissues of plantar fascia and fascia lata. However, palpable tissue release could result from deformation in softer tissues, such as superficial nasal fascia.

In vivo trabecular bone morphologic and mechanical relationship using high-resolution 3-T MRI.

OBJECTIVE: The purpose of this study was to investigate the in vivo morphologic and elastic parameters of trabecular bone with high-resolution 3-T MRI in a healthy reference population. SUBJECTS AND METHODS: A series of wrist MR images were acquired with high-spatial-resolution (180 mum) isotropic voxels from 40 subjects without reported bone disease. After image postprocessing, the bone volume-to-total volume ratio, trabecular thickness, trabecular separation, and trabecular number were calculated in the morphologic analysis. Trabecular bone was mechanically simulated using the finite-element method to calculate the apparent elastic modulus parameter. The relationship between morphologic and mechanical parameters was studied. The influence of the analyzed bone volume was also investigated. RESULTS: Statistically significant sex influences were found on the bone volume-to-total volume ratio (p = 0.003), trabecular thickness (p = 0.02), and apparent elastic modulus (p = 0.01); these parameters were lower in women. However, trends were found only on trabecular separation (p = 0.06) and trabecular number (p = 0.07). Age had no statistically significant influence in any morphologic (bone volume-to-total volume ratio, r = -0.24, p = 0.13; trabecular thickness, r = -0.03, p = 0.88; trabecular separation, r = 0.12, p = 0.47; and trabecular number, r = -0.23, p = 0.16) or elastic (apparent elastic modulus, r = -0.18, p = 0.26) parameter. A statistically significant relationship between apparent elastic modulus and the square of bone volume-to-total volume ratio was found (r = 0.968, p < 0.001). This association was not seen (r = 0.185, p = 0.25) and apparent elastic modulus results were considerably different (p < 0.001) if the volume of analyzed bone was reduced. CONCLUSION: We found that bone volume-to-total volume ratio, trabecular thickness, and apparent elastic modulus are parameters significantly influenced by sex. Apparent elastic modulus results show a relationship with bone volume-to-total volume ratio. Trabecular bone volume should be maximized for an appropriate mechanical analysis.