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Sample records for clinical biomechanics part

  1. Clinical applications of biomechanics cinematography.

    Science.gov (United States)

    Woodle, A S

    1986-10-01

    Biomechanics cinematography is the analysis of movement of living organisms through the use of cameras, image projection systems, electronic digitizers, and computers. This article is a comparison of cinematographic systems and details practical uses of the modality in research and education. PMID:2946390

  2. Biomechanical analysis of plate stabilization on cervical part of spine

    Directory of Open Access Journals (Sweden)

    M. Kiel

    2009-07-01

    Full Text Available Purpose: The main aim of the work was determination of biomechanical analysis of cervical spine – stabilizer system made of stainless steel (Cr-Ni-Mo and Ti-6Al-4V alloy.Design/methodology/approach: To define biomechanical characteristic of the system the finite elements method (FEM was applied. Geometric model of part of spine C5-C7 and stabilizer were discretized by SOLID95 element. Appropriate boundary conditions imitating phenomena in real system with appropriate accuracy were established.Findings: The result of biomechanical analysis was calculation of displacements and stresses in the vertebras and the stabilizer in a function of the applied loading: 50-300 N for the stabilizer made of stainless steel (Cr-Ni-Mo and Ti-6Al-4V alloy.Research limitations/implications: The result of biomechanical analysis for plate stabilizer obtained by FEM can be use to determine a construction features of the stabilizer, and to select mechanical properties of metallic biomaterial and estimation of stabilization quality. The calculation of displacements for part C5-C7 show that the proposed type of stabilizer enables correct stabilization used to clinical apply.Practical implications: The results of biomechanical analysis showed correct mechanical properties used to made the plate stabilizer.Originality/value: The obtained numerical results should be verified in “in vitro” tests.

  3. Using Clinical Gait Case Studies to Enhance Learning in Biomechanics

    Science.gov (United States)

    Chester, Victoria

    2011-01-01

    Clinical case studies facilitate the development of clinical reasoning strategies through knowledge and integration of the basic sciences. Case studies have been shown to be more effective in developing problem-solving abilities than the traditional lecture format. To enhance the learning experiences of students in biomechanics, clinical case…

  4. Focusing on the Hard parts: A Biomechanics Laboratory Exercise

    Science.gov (United States)

    Fingerut, Jonathan; Orbe, Kristina; Flynn, Daniel; Habdas, Piotr

    2013-01-01

    As part of a biomechanics course aimed at both upper-division Biology and Physics majors, this laboratory exercise introduces students to the ingenious ways in which organisms vary the composition and form of support and defensive structures such as bone and shell to maximize their strength while minimizing the energetic cost needed to produce…

  5. Musculoskeletal demands on flamenco dancers: a clinical and biomechanical study.

    Science.gov (United States)

    Bejjani, F J; Halpern, N; Pio, A; Dominguez, R; Voloshin, A; Frankel, V H

    1988-04-01

    The flamenco dancer acts on the floor like a drummer. The percussive footwork and vibration patterns created during dancing impose unusual demands on the musculoskeletal system. This study investigated the clinical and biomechanical aspects of this task. Using the electrodynogram and skin-mounted accelerometers, foot pressures as well as hip and knee vibrations were recorded in 10 female dancers after a thorough clinical evaluation. A health questionnaire was also distributed to 29 dancers. Foot pressures and acceleration data reveal the percussive nature of the dance. Some clinical findings, like calluses, are related to pressure distribution. Urogenital disorders, as well as back and neck pain, may be related to the vibrations generated by the flamenco dance form. The hip joint seems to absorb most of the impacts. "Vibration-pressure" diagrams are suggested as a useful tool for evaluating a dancer's biomechanical behavior, as well as the effect of floors and footwear on this behavior. PMID:3366430

  6. Biomechanics of the spine. Part I: Spinal stability

    Energy Technology Data Exchange (ETDEWEB)

    Izzo, Roberto, E-mail: roberto1766@interfree.it [Neuroradiology Department, “A. Cardarelli” Hospital, Napoli (Italy); Guarnieri, Gianluigi, E-mail: gianluigiguarnieri@hotmail.it [Neuroradiology Department, “A. Cardarelli” Hospital, Napoli (Italy); Guglielmi, Giuseppe, E-mail: g.gugliemi@unifg.it [Department of Radiology, University of Foggia, Foggia (Italy); Muto, Mario, E-mail: mutomar@tiscali.it [Neuroradiology Department, “A. Cardarelli” Hospital, Napoli (Italy)

    2013-01-15

    Biomechanics, the application of mechanical principles to living organisms, helps us to understand how all the bony and soft spinal components contribute individually and together to ensure spinal stability, and how traumas, tumours and degenerative disorders exert destabilizing effects. Spine stability is the basic requirement to protect nervous structures and prevent the early mechanical deterioration of spinal components. The literature reports a number of biomechanical and clinical definitions of spinal stability, but a consensus definition is lacking. Any vertebra in each spinal motion segment, the smallest functional unit of the spine, can perform various combinations of the main and coupled movements during which a number of bony and soft restraints maintain spine stability. Bones, disks and ligaments contribute by playing a structural role and by acting as transducers through their mechanoreceptors. Mechanoreceptors send proprioceptive impulses to the central nervous system which coordinates muscle tone, movement and reflexes. Damage to any spinal structure gives rise to some degree of instability. Instability is classically considered as a global increase in the movements associated with the occurrence of back and/or nerve root pain. The assessment of spinal instability remains a major challenge for diagnostic imaging experts. Knowledge of biomechanics is essential in view of the increasing involvement of radiologists and neuroradiologists in spinal interventional procedures and the ongoing development of new techniques and devices. Bioengineers and surgeons are currently focusing on mobile stabilization systems. These systems represent a new frontier in the treatment of painful degenerative spine and aim to neutralize noxious forces, restore the normal function of spinal segments and protect the adjacent segments. This review discusses the current concepts of spine stability.

  7. Biomechanics of the spine. Part I: Spinal stability

    International Nuclear Information System (INIS)

    Biomechanics, the application of mechanical principles to living organisms, helps us to understand how all the bony and soft spinal components contribute individually and together to ensure spinal stability, and how traumas, tumours and degenerative disorders exert destabilizing effects. Spine stability is the basic requirement to protect nervous structures and prevent the early mechanical deterioration of spinal components. The literature reports a number of biomechanical and clinical definitions of spinal stability, but a consensus definition is lacking. Any vertebra in each spinal motion segment, the smallest functional unit of the spine, can perform various combinations of the main and coupled movements during which a number of bony and soft restraints maintain spine stability. Bones, disks and ligaments contribute by playing a structural role and by acting as transducers through their mechanoreceptors. Mechanoreceptors send proprioceptive impulses to the central nervous system which coordinates muscle tone, movement and reflexes. Damage to any spinal structure gives rise to some degree of instability. Instability is classically considered as a global increase in the movements associated with the occurrence of back and/or nerve root pain. The assessment of spinal instability remains a major challenge for diagnostic imaging experts. Knowledge of biomechanics is essential in view of the increasing involvement of radiologists and neuroradiologists in spinal interventional procedures and the ongoing development of new techniques and devices. Bioengineers and surgeons are currently focusing on mobile stabilization systems. These systems represent a new frontier in the treatment of painful degenerative spine and aim to neutralize noxious forces, restore the normal function of spinal segments and protect the adjacent segments. This review discusses the current concepts of spine stability

  8. Biomechanics and clinical implications of complete edentulous state

    OpenAIRE

    Lalit Kumar, MDS

    2014-01-01

    The edentulous state represents a compromise in the integrity of the masticatory system. It is frequently accompanied by adverse functional and esthetic sequelae, which are varyingly perceived by the affected patient. Perceptions of the edentulous state may range from feelings of inconvenience to feelings of severe handicap because many regard total loss of teeth as equivalent to the loss of a body part. Consequently, the required treatment addresses a range of biomechanical problems that inv...

  9. Weightbath hydrotraction treatment: application, biomechanics, and clinical effects

    Directory of Open Access Journals (Sweden)

    Márta Kurutz

    2010-04-01

    Full Text Available Márta Kurutz1, Tamás Bender21Department of Structural Mechanics, Budapest University of Technology and Economics, Hungary; 2Department of Physical Medicine, Polyclinic and Hospital of the Hospitaller Brothers of St. John of God, Budapest, Medical University of Szeged, HungaryBackground and purpose: Weightbath hydrotraction treatment (WHT is a simple noninvasive effective method of hydro- or balneotherapy to stretch the spine or lower limbs, applied successfully in hospitals and health resort sanitaria in Hungary for more than fifty years. This study aims to introduce WHT with its biomechanical and clinical effects. History, development, equipment, modes of application, biomechanics, spinal traction forces and elongations, indications and contraindications of WHT are precented.Subjects and methods: The calculation of traction forces acting along the spinal column during the treatment is described together with the mode of suspension and the position of extra weight loads applied. The biomechanics of the treatment are completed by in vivo measured elongations of lumbar segments using a special underwater ultrasound measuring method. The clinical effects, indications, and contraindications of the treatment are also presented.Results: In the underwater cervical suspension of a human body, approximately 25 N stretching load occurs in the cervical spine, and about 11 N occurs in the lumbar spine. By applying extra weights, the above tensile forces along the spinal column can be increased. Thus, the traction effect can be controlled by applying such loads during the treatment. Elongations of segments L3–L4, L4–L5, and L5–S1 were measured during the usual WHT of patients suspended cervically in water for 20 minutes, loaded by 20–20 N lead weights on the ankles. The mean initial elastic elongations of spinal segments were about 0.8 mm for patients aged under 40 years, 0.5 mm between 40–60 years, and 0.2 mm for patients over 60 years. The mean

  10. Hip protectors: recommendations for biomechanical testing-an international consensus statement (part I)

    DEFF Research Database (Denmark)

    Robinovitch, S.N.; Evans, S.L.; Minns, J.;

    2009-01-01

    Hip protectors represent a promising strategy for preventing fall-related hip fractures. However, clinical trials have yielded conflicting results due, in part, to lack of agreement on techniques for measuring and optimizing the biomechanical performance of hip protectors as a prerequisite to...... performance of hip protectors. The primary outcome of testing should be the percent reduction (compared with the unpadded condition) in peak value of the axial compressive force applied to the femoral neck during a simulated fall on the greater trochanter. To provide reasonable results, the test system should...

  11. Mystery of alar ligament rupture: Value of MRI in whiplash injuries - biomechanical, anatomical and clinical studies

    International Nuclear Information System (INIS)

    Purpose: Whiplash injury of the cervical spine is a frequent issue in medical expertise and causes enormous consequential costs for motor insurance companies. Some authors accuse posttraumatic changes of alar ligaments to be causative for consequential disturbances. Materials and methods: Review of recent studies on biomechanics, anatomical and clinical MR imaging. Results: Biomechanical experiments can not induce according injuries of alar ligaments. Although MRI provides excellent visualization of alar ligaments, the range of normal variants is high. (orig.)

  12. Structural and biomechanical aspects of equine sacroiliac joint function and their relationship to clinical disease.

    Science.gov (United States)

    Goff, L M; Jeffcott, L B; Jasiewicz, J; McGowan, C M

    2008-06-01

    Pain originating from the sacroiliac joint (SIJ) in horses has long been associated with poor performance, yet specific diagnosis of sacroiliac dysfunction (SID) has been difficult to achieve. Clinical presentation of SID appears to fall into two categories. The first, presenting as pain and poor performance, is responsive to local analgesia of periarticular structures with poorly defined pathology. The second presents primarily as poor performance with bony pathological changes as a result of chronic instability. Diagnostic tests based on biomechanics as well as manual provocation for SIJ pain have formed the basis of tests currently used to diagnose SIJ dysfunction in humans. This review summarises the anatomy and biomechanics of the equine SIJ and current biomechanical, innervation and motor control concepts in human SID. The relationship between abnormal SIJ motion and altered neuromotor control with clinical disease of the equine SIJ are discussed. Future utilisation of these principles to develop new diagnostic and management tools for the equine SID is promising. PMID:17493851

  13. Clinical anatomy and biomechanics of the ankle in dance.

    Science.gov (United States)

    Russell, Jeffrey A; McEwan, Islay M; Koutedakis, Yiannis; Wyon, Matthew A

    2008-01-01

    The ankle is an important joint to understand in the context of dance because it is the connection between the leg and the foot that establishes lower extremity stability. Its function coordinates with the leg and foot and, thus, it is crucial to the dancer's ability to perform. Furthermore, the ankle is one of the most commonly injured body regions in dance. An understanding of ankle anatomy and biomechanics is not only important for healthcare providers working with dancers, but for dance scientists, dance instructors, and dancers themselves. The bony architecture, the soft tissue restraints, and the locomotive structures all integrate to allow the athletic artistry of dance. Yet, there is still much research to be carried out in order to more completely understand the ankle of the dancer. PMID:19618582

  14. Biomechanics of the spine. Part II: Spinal instability

    Energy Technology Data Exchange (ETDEWEB)

    Izzo, Roberto, E-mail: roberto1766@interfree.it [Neuroradiology Department, “A.Cardarelli” Hospital, Napoli (Italy); Guarnieri, Gianluigi, E-mail: gianluigiguarnieri@hotmail.it [Neuroradiology Department, “A.Cardarelli” Hospital, Napoli (Italy); Guglielmi, Giuseppe, E-mail: g.gugliemi@unifg.it [Department of Radiology, University of Foggia, Foggia (Italy); Muto, Mario, E-mail: mutomar@tiscali.it [Neuroradiology Department, “A.Cardarelli” Hospital, Napoli (Italy)

    2013-01-15

    Spine stability is the basic requirement to protect nervous structures and prevent the early deterioration of spinal components. All bony and soft spinal components contribute to stability, so any degenerative, traumatic or destructive lesion to any spinal structure gives rise to some degree of instability. Degenerative instability is considered a major cause of axial and radicular pain and is a frequent indication for surgery. Nevertheless the assessment of instability remains difficult in both clinical and imaging settings. All static imaging modalities, even conventional MR, the most accurate technique, are unreliable in assessing instability and chronic pain due to degenerative spine. Dynamic-positional MR is considered the most sophisticated imaging modality to evaluate abnormal spinal motion and instability. In spinal traumas, as multi-detector CT yields high-resolution reconstructions in every spatial plane, it will detect even the tiniest fractures revealing potentially unstable lesions, often avoid the routine use of MR. Nevertheless, MR remains the only modality that will directly and routinely assess soft tissue changes. Unfortunately the objectivity of MR in assessing the integrity of ligaments is not rigorously defined and its use in routine protocols to clear blunt spinal injuries remains controversial. There are no evidence-based guidelines currently available to assess the risk of spinal instability in the setting of neoplastic spinal disease, so predicting the risk of a pathological fracture or the timing of a collapse remains challenging even when the lesions are well-characterized by neuroimaging. Diagnostic difficulties lead to controversy in the choice of the best treatment in all forms of spinal instability.

  15. Internal fixation on the lower cervical spine – biomechanics and clinical practice of procedures and implants

    OpenAIRE

    Ulrich, Chr.; Arand, M.; Nothwang, J.

    2001-01-01

    The decision to opt for a particular internal fixation procedure of a traumatized unstable lower cervical spine should be based on analysis and implementation of scientific and clinical data on the biomechanics of the intact, the unstable and the implant-fixed spine. The following recommendations for surgical stabilization of the lower cervical spine seem, therefore, to be justified. Firstly, the surgical procedure should be to bring about decompression, realignment, and stability. Secondly, ...

  16. Biomechanics of the Sensor–Tissue Interface—Effects of Motion, Pressure, and Design on Sensor Performance and the Foreign Body Response—Part I: Theoretical Framework

    OpenAIRE

    Helton, Kristen L; Ratner, Buddy D.; Wisniewski, Natalie A

    2011-01-01

    The importance of biomechanics in glucose sensor function has been largely overlooked. This article is the first part of a two-part review in which we look beyond commonly recognized chemical biocompatibility to explore the biomechanics of the sensor–tissue interface as an important aspect of continuous glucose sensor biocompatibility. Part I provides a theoretical framework to describe how biomechanical factors such as motion and pressure (typically micromotion and micropressure) give rise t...

  17. [Modern biomechanical poroeslatic model of bone tissue. Part II--structure of pore space in cortical and trabecular bone].

    Science.gov (United States)

    Rogala, Piotr; Uklejewski, Ryszard; Stryła, Wanda

    2002-01-01

    In modern bone biomechanics the bone tissue is treated as a porous elastically deformed solid filled with a viscous newtonian fluid (two-phase poroelastic model) [41]. Traditional one-phase biomechanical model of bone tissue is still valid and it can be considered as an approximate model in comparison with the more realistic two-phase model of bone tissue. Hierarchical biostructure of the pore space of cortical and trabecular bone is presented, including the compartments of bone pore space after Cowin [12, 13]. Examples of clinical amplications of the poroelastic model of bone tissue such as: osteoporosis, porous coated implants, bone electromagnetostimulation in rehabilitation are indicated. PMID:12418404

  18. Inertial measures of motion for clinical biomechanics: comparative assessment of accuracy under controlled conditions - changes in accuracy over time.

    Directory of Open Access Journals (Sweden)

    Karina Lebel

    Full Text Available Interest in 3D inertial motion tracking devices (AHRS has been growing rapidly among the biomechanical community. Although the convenience of such tracking devices seems to open a whole new world of possibilities for evaluation in clinical biomechanics, its limitations haven't been extensively documented. The objectives of this study are: 1 to assess the change in absolute and relative accuracy of multiple units of 3 commercially available AHRS over time; and 2 to identify different sources of errors affecting AHRS accuracy and to document how they may affect the measurements over time.This study used an instrumented Gimbal table on which AHRS modules were carefully attached and put through a series of velocity-controlled sustained motions including 2 minutes motion trials (2MT and 12 minutes multiple dynamic phases motion trials (12MDP. Absolute accuracy was assessed by comparison of the AHRS orientation measurements to those of an optical gold standard. Relative accuracy was evaluated using the variation in relative orientation between modules during the trials.Both absolute and relative accuracy decreased over time during 2MT. 12MDP trials showed a significant decrease in accuracy over multiple phases, but accuracy could be enhanced significantly by resetting the reference point and/or compensating for initial Inertial frame estimation reference for each phase.The variation in AHRS accuracy observed between the different systems and with time can be attributed in part to the dynamic estimation error, but also and foremost, to the ability of AHRS units to locate the same Inertial frame.Mean accuracies obtained under the Gimbal table sustained conditions of motion suggest that AHRS are promising tools for clinical mobility assessment under constrained conditions of use. However, improvement in magnetic compensation and alignment between AHRS modules are desirable in order for AHRS to reach their full potential in capturing clinical outcomes.

  19. Neurofibromatosis: part 2--clinical management.

    Science.gov (United States)

    Batista, Pollyanna Barros; Bertollo, Eny Maria Goloni; Costa, Danielle de Souza; Eliam, Lucas; Cunha, Karin Soares Gonçalves; Cunha-Melo, José Renan; Darrigo Junior, Luiz Guilherme; Geller, Mauro; Gianordoli-Nascimento, Ingrid Faria; Madeira, Luciana Gonçalves; Mendes, Hérika Martins; Miranda, Débora Marques de; Mata-Machado, Nikolas Andre; Morato, Eric Grossi; Pavarino, Érika Cristina; Pereira, Luciana Baptista; Rezende, Nilton Alves de; Rodrigues, Luíza de Oliveira; Sette, Jorge Bezerra Cavalcanti

    2015-06-01

    Part 1 of this guideline addressed the differential diagnosis of the neurofibromatoses (NF): neurofibromatosis type 1 (NF1), neurofibromatosis type 2 (NF2) and schwannomatosis (SCH). NF shares some features such as the genetic origin of the neural tumors and cutaneous manifestations, and affects nearly 80 thousand Brazilians. Increasing scientific knowledge on NF has allowed better clinical management and reduced rate of complications and morbidity, resulting in higher quality of life for NF patients. Most medical doctors are able to perform NF diagnosis, but the wide range of clinical manifestations and the inability to predict the onset or severity of new features, consequences, or complications make NF management a real clinical challenge, requiring the support of different specialists for proper treatment and genetic counseling, especially in NF2 and SCH. The present text suggests guidelines for the clinical management of NF, with emphasis on NF1. PMID:26083891

  20. Traumatic Extensor Tendon Injuries to the Hand: Clinical Anatomy, Biomechanics, and Surgical Procedure Review.

    Science.gov (United States)

    Colzani, Giulia; Tos, Pierluigi; Battiston, Bruno; Merolla, Giovanni; Porcellini, Giuseppe; Artiaco, Stefano

    2016-04-01

    The extensor apparatus is a complex muscle-tendon system that requires integrity or optimal reconstruction to preserve hand function. Anatomical knowledge and the understanding of physiopathology of extensor tendons are essential for an accurate diagnosis of extensor tendon injuries (ETIs) of the hand and wrist, because these lesions are complex and commonly observed in clinical practice. A careful clinical history and assessment still remain the first step for the diagnosis, followed by US and MR to confirm the suspect of ETI or to investigate some doubtful conditions and rule out associate lesions. During last decades the evolution of surgical techniques and rehabilitative treatment protocol led to gradual improvement in clinical results of ETI treatment and surgical repair. Injury classification into anatomical zones and the evaluation of the characteristics of the lesions are considered key points to select the appropriate treatment for ETI. Both conservative and surgical management can be indicated in ETI, depending on the anatomical zone and on the characteristics of the injuries. As a general rule, an attempt of conservative treatment should be performed when the lesion is expected to have favorable result with nonoperative procedure. Many surgical techniques have been proposed over the time and with favorable results if the tendon injury is not underestimated and adequately treated. Despite recent research findings, a lack of evidence-based knowledge is still observed in surgical treatment and postoperative management of ETI. Further clinical and biomechanical investigations would be advisable to clarify this complex issue. PMID:27616821

  1. Clinical and biomechanical outcome of minimal invasive and open repair of the Achilles tendon

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    Chan Alexander

    2011-12-01

    Full Text Available Abstract Introduction With evolutions in surgical techniques, minimally invasive surgical (MIS repair with Achillon applicator has been introduced. However, there is still a lack of literature to investigate into the clinical merits of MIS over open surgery. This study aims to investigate the correlation between clinical outcome, gait analysis and biomechanical properties comparing both surgical methods. Materials and methods A single centre retrospective review on all the consecutive operated patients between January 2004 and December 2008 was performed. Twenty-six patients (19 male and 7 female; age 40.4 ± 9.2 years had experienced a complete Achilles tendon rupture with operative repair. Nineteen of the patients, 10 MIS versus 9 open repairs (13 men with a mean age of 40.54 ± 10.43 (range 23-62 yrs and 6 women with a mean age of 45.33 ± 7.71 (range 35-57 yrs were further invited to attend a thorough clinical assessment using Holz's scale and biomechanical evaluation at a mean of 25.3 months after operation. This study utilized the Cybex II isokinetic dynamometer to assess the isokinetic peak force of plantar-flexion and dorsiflexion of both ankles. The patients were also invited to return to our Gait Laboratory for analysis. The eight-infrared camera motion capture system (VICON, UK was utilized for the acquisition of kinematic variables. Their anthropometric data was measured according to the Davis and coworkers' standard. Results The mean operative time and length of hospital stay were shorter in the MIS group. The operative time was 54.55 ± 15.15 minutes versus 68.80 ± 18.23 minutes of the MIS group and Open group respectively (p = 0.045, whereas length of stay was 3.36 ± 1.21 days versus 6.40 ± 3.70 days respectively (p = 0.039. There is statistically significant decrease (p = 0.005 in incision length in MIS group than the open surgery group, 3.23 ± 1.10 cm versus 9.64 ± 2.55 cm respectively. Both groups attained similar Holz

  2. Open Knee: Open Source Modeling & Simulation to Enable Scientific Discovery and Clinical Care in Knee Biomechanics

    Science.gov (United States)

    Erdemir, Ahmet

    2016-01-01

    Virtual representations of the knee joint can provide clinicians, scientists, and engineers the tools to explore mechanical function of the knee and its tissue structures in health and disease. Modeling and simulation approaches such as finite element analysis also provide the possibility to understand the influence of surgical procedures and implants on joint stresses and tissue deformations. A large number of knee joint models are described in the biomechanics literature. However, freely accessible, customizable, and easy-to-use models are scarce. Availability of such models can accelerate clinical translation of simulations, where labor intensive reproduction of model development steps can be avoided. The interested parties can immediately utilize readily available models for scientific discovery and for clinical care. Motivated by this gap, this study aims to describe an open source and freely available finite element representation of the tibiofemoral joint, namely Open Knee, which includes detailed anatomical representation of the joint's major tissue structures, their nonlinear mechanical properties and interactions. Three use cases illustrate customization potential of the model, its predictive capacity, and its scientific and clinical utility: prediction of joint movements during passive flexion, examining the role of meniscectomy on contact mechanics and joint movements, and understanding anterior cruciate ligament mechanics. A summary of scientific and clinically directed studies conducted by other investigators are also provided. The utilization of this open source model by groups other than its developers emphasizes the premise of model sharing as an accelerator of simulation-based medicine. Finally, the imminent need to develop next generation knee models are noted. These are anticipated to incorporate individualized anatomy and tissue properties supported by specimen-specific joint mechanics data for evaluation, all acquired in vitro from varying age

  3. A biomechanical model of the wrist joint for patient-specific model guided surgical therapy: Part 2.

    Science.gov (United States)

    Eschweiler, Jörg; Stromps, Jan-Philipp; Fischer, Maximilian; Schick, Fabian; Rath, Björn; Pallua, Norbert; Radermacher, Klaus

    2016-04-01

    An enhanced musculoskeletal biomechanical model of the wrist joint is presented in this article. The computational model is based on the multi-body simulation software AnyBody. Multi body dynamic musculoskeletal models capable of predicting muscle forces and joint contact pressures simultaneously would be valuable for studying clinical issues related to wrist joint degeneration and restoration. In this study, the simulation model of the wrist joint was used for investigating deeper the biomechanical function of the wrist joint. In representative physiological scenarios, the joint behavior and muscle forces were computed. Furthermore, the load transmission of the proximal wrist joint was investigated. The model was able to calculate the parameters of interest that are not easily obtainable experimentally, such as muscle forces and proximal wrist joint forces. In the case of muscle force investigation, the computational model was able to accurately predict the computational outcome for flexion and extension motion. In the case of force distribution of the proximal wrist joint, the model was able to predict accurately the computational outcome for an axial load of 140 N. The presented model and approach of using a multi-body simulation model are anticipated to have value as a predictive clinical tool including effect of injuries or anatomical variations and initial outcome of surgical procedures for patient-specific planning and custom implant design. Therefore, patient-specific multi-body simulation models are potentially valuable tools for surgeons in pre- and intraoperative planning of implant placement and orientation. PMID:26994118

  4. Lumbar spine endplate fractures: Biomechanical evaluation and clinical considerations through experimental induction of injury.

    Science.gov (United States)

    Curry, William H; Pintar, Frank A; Doan, Ninh B; Nguyen, Ha Son; Eckardt, Gerald; Baisden, Jamie L; Maiman, Dennis J; Paskoff, Glenn R; Shender, Barry S; Stemper, Brian D

    2016-06-01

    Lumbar endplate fractures were investigated in different experimental scenarios, however the biomechanical effect of segmental alignment was not outlined. The objectives of this study were to quantify effects of spinal orientation on lumbar spine injuries during single-cycle compressive loads and understand lumbar spine endplate injury tolerance. Twenty lumbar motion segments were compressed to failure. Two methods were used in the preparation of the lumbar motion segments. Group 1 (n = 7) preparation maintained pre-test sagittal lordosis, whereas Group 2 (n = 13) specimens had a free-rotational end condition for the cranial vertebra, allowing sagittal rotation of the cranial vertebra to create parallel endplates. Five Group 1 specimens experienced posterior vertebral body fracture prior to endplate fracture, whereas two sustained endplate fracture only. Group 2 specimens sustained isolated endplate fractures. Group 2 fractures occurred at approximately 41% of the axial force required for Group 1 fracture (p < 0.05). Imaging and specimen dissection indicate endplate injury consistently took place within the confines of the endplate boundaries, away from the vertebral periphery. These findings indicate that spinal alignment during compressive loading influences the resulting injury pattern. This investigation identified the specific mechanical conditions under which an endplate breach will take place. Development of endplate injuries has significant clinical implication as previous research identified internal disc disruption (IDD) and degenerative disc disease (DDD) as long-term consequences of the axial load-shift that occurs following a breach of the endplate. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1084-1091, 2016. PMID:26610067

  5. Biomechanics of oral mucosa

    Science.gov (United States)

    Chen, Junning; Ahmad, Rohana; Li, Wei; Swain, Michael; Li, Qing

    2015-01-01

    The prevalence of prosthodontic treatment has been well recognized, and the need is continuously increasing with the ageing population. While the oral mucosa plays a critical role in the treatment outcome, the associated biomechanics is not yet fully understood. Using the literature available, this paper provides a critical review on four aspects of mucosal biomechanics, including static, dynamic, volumetric and interactive responses, which are interpreted by its elasticity, viscosity/permeability, apparent Poisson's ratio and friction coefficient, respectively. Both empirical studies and numerical models are analysed and compared to gain anatomical and physiological insights. Furthermore, the clinical applications of such biomechanical knowledge on the mucosa are explored to address some critical concerns, including stimuli for tissue remodelling (interstitial hydrostatic pressure), pressure–pain thresholds, tissue displaceability and residual bone resorption. Through this review, the state of the art in mucosal biomechanics and their clinical implications are discussed for future research interests, including clinical applications, computational modelling, design optimization and prosthetic fabrication. PMID:26224566

  6. The appropriate use of radiography in clinical practice: a report of two cases of biomechanical versus malignant spine pain

    Directory of Open Access Journals (Sweden)

    Wyatt Lawrence H

    2006-05-01

    Full Text Available Abstract Background To describe the evaluation, treatment, management and referral of two patients with back pain with an eventual malignant etiology, who were first thought to have a non-organic biomechanical disorder. Clinical features The study was a retrospective review of the clinical course of two patients seen by a chiropractor in a multi-disciplinary outpatient facility, who presented with what was thought to be non-organic biomechanical spine pain. Clinical examination by both medical and chiropractic physicians did not indicate the need for radiography in the early course of management of either patient. Upon subsequent re-evaluation, it was decided that certain clinical factors required investigation with advanced imaging. In one instance, the patient responded to conservative care of low back pain for nine weeks, after which she developed severe pain in the pelvis. In the second case, the patient presented with signs and symptoms consistent with uncomplicated musculoskeletal pain that failed to respond to a course of conservative care. He was referred for medical therapy which also failed to relieve his pain. In both patients, malignancy was eventually discovered with magnetic resonance imaging and both patients are now deceased, resulting in an inability to obtain informed consent for the publication of this manuscript. Conclusion In these two cases, the prudent use of diagnostic plain film radiography did not significantly alter the appropriate long-term management of patients with neuromusculoskeletal signs and symptoms. The judicious use of magnetic resonance imaging was an effective procedure when investigating recalcitrant neuromusculoskeletal pain in these two patients.

  7. The sterno-clavicular joint: anatomy, biomechanic, clinical features and aspects of manual therapy

    Directory of Open Access Journals (Sweden)

    M. Cutolo

    2011-09-01

    Full Text Available The sterno-clavicular joint covers one remarkable importance in the complex of the shoulder girdle. This review investigates the anatomy, biomechanics, main affections and involvement of this joint in the pathological processes of the shoulder girdle in its complex. Moreover, it focuses on the opportunities offered from the conservative treatment, using in particular the manual therapy. Active and passive, as well as against isometric resistance movements, are discussed. In particular, the passive mobilization is demonstrated effective in the restoration of joint mobility. The sterno- clavicular joint is not structured in order to complete great work loads and has the tendency to become hypermotile or unstable, if subordinate to overload works, becoming painful. In this case, the techniques of passive mobilization and of modulation of the pain turn out effective.

  8. Biomechanical and clinical evaluation of a newly designed polycentric knee of transfemoral prosthesis.

    Science.gov (United States)

    Yokogushi, Kazutoshi; Narita, Hiroshi; Uchiyama, Eiichi; Chiba, Susumu; Nosaka, Toshiya; Yamakoshi, Ken-ichi

    2004-09-01

    We have designed a new polycentric knee adopting a hydraulic unit and an intelligent mechanism. The biomechanical parameters of this prototype, such as the stance duration, peak knee flexion angle in stance and swing, peak hip flexion angle, and peak hip extension moments were analyzed at three different cadences (88, 96, 104 steps/min) in three amputees, and then compared to those of polycentric hydraulic knees currently in use. The same parameters were also measured for 10 healthy volunteers and subsequently analyzed. In the prototype, almost all the values of the parameters showed no significant variety in individuals at the different cadences. The situation was the same with the healthy volunteers. However, the values of the parameter for the conventional knee varied significantly with the individual at the different cadences. The prototype may be of practical use, contributing to a stable walk even at different cadences. PMID:15558397

  9. Neurofibromatosis: part 2 – clinical management

    Directory of Open Access Journals (Sweden)

    Pollyanna Barros Batista

    2015-06-01

    Full Text Available Part 1 of this guideline addressed the differential diagnosis of the neurofibromatoses (NF: neurofibromatosis type 1 (NF1, neurofibromatosis type 2 (NF2 and schwannomatosis (SCH. NF shares some features such as the genetic origin of the neural tumors and cutaneous manifestations, and affects nearly 80 thousand Brazilians. Increasing scientific knowledge on NF has allowed better clinical management and reduced rate of complications and morbidity, resulting in higher quality of life for NF patients. Most medical doctors are able to perform NF diagnosis, but the wide range of clinical manifestations and the inability to predict the onset or severity of new features, consequences, or complications make NF management a real clinical challenge, requiring the support of different specialists for proper treatment and genetic counseling, especially in NF2 and SCH. The present text suggests guidelines for the clinical management of NF, with emphasis on NF1.

  10. Neurofibromatosis: part 2 – clinical management

    OpenAIRE

    Pollyanna Barros Batista; Eny Maria Goloni Bertollo; Danielle de Souza Costa; Lucas Eliam; Karin Soares Gonçalves Cunha; José Renan Cunha-Melo; Luiz Guilherme Darrigo Junior; Mauro Geller; Ingrid Faria Gianordoli-Nascimento; Luciana Gonçalves Madeira; Hérika Martins Mendes; Débora Marques Miranda; Nikolas Andre Mata-Machado; Eric Grossi Morato; Érika Cristina Pavarino

    2015-01-01

    Part 1 of this guideline addressed the differential diagnosis of the neurofibromatoses (NF): neurofibromatosis type 1 (NF1), neurofibromatosis type 2 (NF2) and schwannomatosis (SCH). NF shares some features such as the genetic origin of the neural tumors and cutaneous manifestations, and affects nearly 80 thousand Brazilians. Increasing scientific knowledge on NF has allowed better clinical management and reduced rate of complications and morbidity, resulting in higher quality of life for NF ...

  11. Inter-assessor reliability of practice based biomechanical assessment of the foot and ankle

    OpenAIRE

    Jarvis Hannah L; Nester Christopher J; Jones Richard K; Williams Anita; Bowden Peter D

    2012-01-01

    Abstract Background There is no consensus on which protocols should be used to assess foot and lower limb biomechanics in clinical practice. The reliability of many assessments has been questioned by previous research. The aim of this investigation was to (i) identify (through consensus) what biomechanical examinations are used in clinical practice and (ii) evaluate the inter-assessor reliability of some of these examinations. Methods Part1: Using a modified Delphi technique 12 podiatrists de...

  12. Ocular biomechanics study: current state and perspectives

    Directory of Open Access Journals (Sweden)

    S. Yu. Petrov

    2015-03-01

    Full Text Available Despite the fact that the eye represents a challenge for biomechanical research due to its size, over the last two decades, much data on ocular biomechanics were accumulated. Scleral and lamina cribrosa biomechanics contribute to our understanding of myopia and open-angle glaucoma; iris and trabecular meshwork biomechanics to that of angle-closure glaucoma; vitreous biomechanics to that of retinal detachment and ocular drug delivery; corneal biomechanics to that of keratoconus; and lens capsule biomechanics to that of cataract. This paper offers a general overview of recent advances in corneal, scleral, crystalline lens, and lamina cribrosa biomechanics and summarizes the results of experimental and clinical studies. Ocular biomechanics abnormalities affect etiology of many eye diseases. Ocular biomechanics plays an important role in the development of novel diagnostic methods, therapeutic and surgical procedures. Corneal biomechanics impacts etiology and pathogenesis of keratoconus as well as tonometry accuracy and explains corneal refractive surgery effect. Scleral biomechanics is associated with IOP and progressive myopia. Accommodative apparatus (ciliary body and crystalline lens is an important anatomic physiological structure. Recent studies uncovered the causes of agerelated loss of accommodation as a result of lens involution. Optic nerve head abnormalities due to IOP fluctuations are the key factor of glaucomatous neuropathy. They are directly associated with ocular biomechanics as well.

  13. Hallux Valgus and the First Tarsometatarsal Joint: Clinical and Biomechanical Aspects

    NARCIS (Netherlands)

    F.W.M. Faber (Frank)

    2003-01-01

    textabstractThis thesis describes a series of cadaver, experimental, radiographic and clinical studies on the relation between a hallux valgus deformity and mobility of the first tarsometatarsal joint. Hypermobility of stiffnes of the joint was determined by Doppler imaging of vibrations and by radi

  14. Conformal piezoelectric systems for clinical and experimental characterization of soft tissue biomechanics

    Science.gov (United States)

    Dagdeviren, Canan; Shi, Yan; Joe, Pauline; Ghaffari, Roozbeh; Balooch, Guive; Usgaonkar, Karan; Gur, Onur; Tran, Phat L.; Crosby, Jessi R.; Meyer, Marcin; Su, Yewang; Chad Webb, R.; Tedesco, Andrew S.; Slepian, Marvin J.; Huang, Yonggang; Rogers, John A.

    2015-07-01

    Mechanical assessment of soft biological tissues and organs has broad relevance in clinical diagnosis and treatment of disease. Existing characterization methods are invasive, lack microscale spatial resolution, and are tailored only for specific regions of the body under quasi-static conditions. Here, we develop conformal and piezoelectric devices that enable in vivo measurements of soft tissue viscoelasticity in the near-surface regions of the epidermis. These systems achieve conformal contact with the underlying complex topography and texture of the targeted skin, as well as other organ surfaces, under both quasi-static and dynamic conditions. Experimental and theoretical characterization of the responses of piezoelectric actuator-sensor pairs laminated on a variety of soft biological tissues and organ systems in animal models provide information on the operation of the devices. Studies on human subjects establish the clinical significance of these devices for rapid and non-invasive characterization of skin mechanical properties.

  15. Hallux Valgus and the First Tarsometatarsal Joint: Clinical and Biomechanical Aspects

    OpenAIRE

    Faber, Frank

    2003-01-01

    textabstractThis thesis describes a series of cadaver, experimental, radiographic and clinical studies on the relation between a hallux valgus deformity and mobility of the first tarsometatarsal joint. Hypermobility of stiffnes of the joint was determined by Doppler imaging of vibrations and by radiographic stress measurement. With neither method a sharp distinction between hypermobility and non-hypermobility of the joint could be made. Comparison of the Hohmann surgical procedure with the La...

  16. Biomechanical assessment and clinical analysis of different intramedullary nailing systems for oblique fractures.

    Science.gov (United States)

    Alierta, J A; Pérez, M A; Seral, B; García-Aznar, J M

    2016-09-01

    The aim of this study is to evaluate the fracture union or non-union for a specific patient that presented oblique fractures in tibia and fibula, using a mechanistic-based bone healing model. Normally, this kind of fractures can be treated through an intramedullary nail using two possible configurations that depends on the mechanical stabilisation: static and dynamic. Both cases are simulated under different fracture geometries in order to understand the effect of the mechanical stabilisation on the fracture healing outcome. The results of both simulations are in good agreement with previous clinical experience. From the results, it is demonstrated that the dynamization of the fracture improves healing in comparison with a static or rigid fixation of the fracture. This work shows the versatility and potential of a mechanistic-based bone healing model to predict the final outcome (union, non-union, delayed union) of realistic 3D fractures where even more than one bone is involved. PMID:26712100

  17. Biomechanics: basic and applied research

    International Nuclear Information System (INIS)

    This volume presents the state of the art in biomechanics. The most recent achievements of biomechanical research in the fields of orthopaedics, dynamics of the musculoskeletal system, hard and soft tissues, rehabilitation, sports, cardiovascular problems and research methodology have been selected and edited by a distinguished panel of reviewers. The material is such that the volume will serve as a reference for many years for bioengineers, sports scientists, clinicians and clinical researchers in rehabilitation, orthopaedics and cardiovascular surgery

  18. Mathematical foundations of biomechanics.

    Science.gov (United States)

    Niederer, Peter F

    2010-01-01

    The aim of biomechanics is the analysis of the structure and function of humans, animals, and plants by means of the methods of mechanics. Its foundations are in particular embedded in mathematics, physics, and informatics. Due to the inherent multidisciplinary character deriving from its aim, biomechanics has numerous connections and overlapping areas with biology, biochemistry, physiology, and pathophysiology, along with clinical medicine, so its range is enormously wide. This treatise is mainly meant to serve as an introduction and overview for readers and students who intend to acquire a basic understanding of the mathematical principles and mechanics that constitute the foundation of biomechanics; accordingly, its contents are limited to basic theoretical principles of general validity and long-range significance. Selected examples are included that are representative for the problems treated in biomechanics. Although ultimate mathematical generality is not in the foreground, an attempt is made to derive the theory from basic principles. A concise and systematic formulation is thereby intended with the aim that the reader is provided with a working knowledge. It is assumed that he or she is familiar with the principles of calculus, vector analysis, and linear algebra. PMID:21303323

  19. A review of biomechanics of the shoulder and biomechanical concepts of rotator cuff repair

    Directory of Open Access Journals (Sweden)

    Nobuyuki Yamamoto

    2015-01-01

    Full Text Available In this article, we describe the basic knowledge about shoulder biomechanics, which is thought to be useful for surgeons. Some clinical reports have described that the excellent outcome after cuff repair without acromioplasty and a limited acromioplasty might be enough for subacromial decompression. It was biomechanically demonstrated that a 10-mm medial shift of the tendon repair site has a minimum effect on biomechanics. Many biomechanical studies reported that the transosseous equivalent repair was superior to other techniques, although the tendon may lose its inherent elasticity. We herein introduce our recent experiment data and latest information on biomechanics.

  20. Development of a biomechanical model of the wrist joint for patient-specific model guided surgical therapy planning: Part 1.

    Science.gov (United States)

    Eschweiler, Jörg; Stromps, Jan-Philipp; Fischer, Maximilian; Schick, Fabian; Rath, Björn; Pallua, Norbert; Radermacher, Klaus

    2016-04-01

    An enhanced musculoskeletal biomechanical model of the wrist joint is presented in this article. The developed computational model features the two forearm bones radius and ulna, the eight wrist bones, the five metacarpal bones, and a soft tissue apparatus. Validation of the model was based on information taken from the literature as well as own experimental passive in vitro motion analysis of eight cadaver specimens. The computational model is based on the multi-body simulation software AnyBody. A comprehensive ligamentous apparatus was implemented allowing the investigation of ligament function. The model can easily patient specific personalized on the basis of image information. The model enables simulation of individual wrist motion and predicts trends correctly in the case of changing kinematics. Therefore, patient-specific multi-body simulation models are potentially valuable tools for surgeons in pre- and intraoperative planning of implant placement and orientation. PMID:26994117

  1. Clinical leadership part 2: leadership styles.

    Science.gov (United States)

    Fowler, John

    2016-05-12

    John Fowler, independent education consultant, introduces his new series on the role that clinically based nurses can have in leadership, and on the overlapping areas of leadership and management. PMID:27172500

  2. Pedicle-Screw-Based Dynamic Systems and Degenerative Lumbar Diseases: Biomechanical and Clinical Experiences of Dynamic Fusion with Isobar TTL

    OpenAIRE

    Cédric Barrey; Gilles Perrin; Sabina Champain

    2013-01-01

    Dynamic systems in the lumbar spine are believed to reduce main fusion drawbacks such as pseudarthrosis, bone rarefaction, and mechanical failure. Compared to fusion achieved with rigid constructs, biomechanical studies underlined some advantages of dynamic instrumentation including increased load sharing between the instrumentation and interbody bone graft and stresses reduction at bone-to-screw interface. These advantages may result in increased fusion rates, limitation of bone rarefaction,...

  3. Shoulder biomechanics

    Energy Technology Data Exchange (ETDEWEB)

    Lugo, Roberto; Kung, Peter; Ma, C. Benjamin [Sports Medicine and Shoulder Service, University of California, San Francisco, 500 Parnassus Avenue, MU 320W-0728 San Francisco, CA 914143 (United States)], E-mail: maben@orthosurg.ucsf.edu

    2008-10-15

    The biomechanics of the glenohumeral joint depend on the interaction of both static and dynamic-stabilizing structures. Static stabilizers include the bony anatomy, negative intra-articular pressure, the glenoid labrum, and the glenohumeral ligaments along with the joint capsule. The dynamic-stabilizing structures include the rotator cuff muscles and the other muscular structures surrounding the shoulder joint. The combined effect of these stabilizers is to support the multiple degrees of motion within the glenohumeral joint. The goal of this article is to review how these structures interact to provide optimal stability and how failure of some of these mechanisms can lead to shoulder joint pathology.

  4. Rule based Part of speech Tagger for Homoeopathy Clinical realm

    OpenAIRE

    Sanjay Kumar Dwivedi; Pramod P Sukhadeve

    2011-01-01

    A tagger is a mandatory segment of most text scrutiny systems, as it consigned a syntax class (e.g., noun, verb, adjective, and adverb) to every word in a sentence. In this paper, we present a simple part of speech tagger for homoeopathy clinical language. This paper reports about the anticipated part of speech tagger for homoeopathy clinical language. It exploit standard pattern for evaluating sentences, untagged clinical corpus of 20085 words is used, from which we had selected 125 sentence...

  5. Magnetic resonance urography. Part 2 - clinical applications

    International Nuclear Information System (INIS)

    MR urography is a new, modern modality for evaluation of various urological abnormalities. MR urography provides both morphological and functional information. The method is clinically useful in the evaluation of the collecting system, variants and congenital abnormalities of the kidney, tumors and inflammatory diseases, hematuria. Correlation is made with MDCT urography. MR urography is particularly beneficial in pediatrics and pregnant patients. It can be useful in patients with renal insufficiency, and if contra indications to conventional radiological examination are considered. The role of MRU in patients for the preoperative assessment and the follow-up after renal transplantation is emerging. Nephrogenic system fibrosis have been discussed as potential risk to gadolinium contrast enhanced MR urography. MR urography is promising diagnostic method in a wide spectrum of pathological conditions affecting the urinary tract. It is highly informative and overcomes a lot of limitations of the other imaging modalities

  6. Biomechanics finds practical applications in aerospace research

    Science.gov (United States)

    Yanghe, X.

    1984-10-01

    Biomechanics is a branch of science which studies the mechanical properties of biological parts using the basic principles of mechanics and engineering. Formulas and quantitative calculations are used to analyze and understand physiological phenomena. Problems caused by weightlessness, coronary heart disease, blood circulation, use of medication, and application of biomechanics in aviation rescue are discussed.

  7. Molecular diagnostics clinical utility strategy: a six-part framework.

    Science.gov (United States)

    Frueh, Felix W; Quinn, Bruce

    2014-09-01

    The clinical utility of a molecular test rises proportional to a favorable regulatory risk/benefit assessment, and clinical utility is the driver of payer coverage decisions. Although a great deal has been written about clinical utility, debates still center on its 'definition.' We argue that the definition (an impact on clinical outcomes) is self-evident, and improved communications should focus on sequential steps in building and proving an adequate level of confidence for the diagnostic test's clinical value proposition. We propose a six-part framework to facilitate communications between test developers and health technology evaluators, relevant to both regulatory and payer decisions. PMID:25109921

  8. Carpal height and postoperative strength after proximal row carpectomy or four-corner arthrodesis: Clinical, anatomical and biomechanical study.

    Science.gov (United States)

    Laronde, Pascale; Christiaens, Nicolas; Aumar, Aurélien; Chantelot, Christophe; Fontaine, Christian

    2016-04-01

    Proximal row carpectomy (PRC) and four-corner arthrodesis (4CA) are the two most commonly performed surgical procedures to treat wrist arthritis. Postoperative strength is one of the criteria for choosing between the two techniques. Some authors believe that strength is correlated with residual carpal height. The goal of this study was to determine if postoperative carpal height was predictive of postoperative strength. This study consisted of two parts: a clinical evaluation of grip strength after 4CA or PRC; anatomical and radiological measurements of carpal height before and after 4CA or PRC. Grip strength was better preserved after PRC (87.5%) than after 4CA (76.1%), when expressed relative to the opposite hand (P=0.053). There was a significant decrease in carpal height for the PRC group with a Youm's index of 0.37 versus 0.50 for the 4CA group (P<0.0001). Our clinical results and analysis of the literature indicate that 4CA is not superior to PRC when it comes to grip strength, whereas carpal height is significantly decreased after PRC. The decreased tendon excursion after PRC is balanced by an increase in joint stresses after 4CA. PMID:27117123

  9. Rule based Part of speech Tagger for Homoeopathy Clinical realm

    CERN Document Server

    Dwivedi, Sanjay K

    2011-01-01

    A tagger is a mandatory segment of most text scrutiny systems, as it consigned a s yntax class (e.g., noun, verb, adjective, and adverb) to every word in a sentence. In this paper, we present a simple part of speech tagger for homoeopathy clinical language. This paper reports about the anticipated part of speech tagger for homoeopathy clinical language. It exploit standard pattern for evaluating sentences, untagged clinical corpus of 20085 words is used, from which we had selected 125 sentences (2322 tokens). The problem of tagging in natural language processing is to find a way to tag every word in a text as a meticulous part of speech. The basic idea is to apply a set of rules on clinical sentences and on each word, Accuracy is the leading factor in evaluating any POS tagger so the accuracy of proposed tagger is also conversed.

  10. Rule based Part of speech Tagger for Homoeopathy Clinical realm

    Directory of Open Access Journals (Sweden)

    Sanjay Kumar Dwivedi

    2011-07-01

    Full Text Available A tagger is a mandatory segment of most text scrutiny systems, as it consigned a syntax class (e.g., noun, verb, adjective, and adverb to every word in a sentence. In this paper, we present a simple part of speech tagger for homoeopathy clinical language. This paper reports about the anticipated part of speech tagger for homoeopathy clinical language. It exploit standard pattern for evaluating sentences, untagged clinical corpus of 20085 words is used, from which we had selected 125 sentences (2322 tokens. The problem of tagging in natural language processing is to find a way to tag every word in a text as a meticulous part of speech. The basic idea is to apply a set of rules on clinical sentences and on each word, Accuracy is the leading factor in evaluating any POS tagger so the accuracy of proposed tagger is also conversed.

  11. Biomechanics in Schools.

    Science.gov (United States)

    Vincent, J. F. V.

    1980-01-01

    Examines current usage of the term "biomechanics" and emphasizes the importance of differentiating between structure and material. Describes current prolects in biomechanics and lists four points about the educational significance of the field. (GS)

  12. Biomechanical Stability of Dental Implants in Augmented Maxillary Sites: Results of a Randomized Clinical Study with Four Different Biomaterials and PRF and a Biological View on Guided Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Troedhan Angelo

    2015-01-01

    Full Text Available Introduction. Bone regenerates mainly by periosteal and endosteal humoral and cellular activity, which is given only little concern in surgical techniques and choice of bone grafts for guided bone regeneration. This study investigates on a clinical level the biomechanical stability of augmented sites in maxillary bone when a new class of moldable, self-hardening calcium-phosphate biomaterials (SHB is used with and without the addition of Platelet Rich Fibrin (aPRF in the Piezotome-enhanced subperiosteal tunnel-technique (PeSPTT. Material and Methods. 82 patients with horizontal atrophy of anterior maxillary crest were treated with PeSPTT and randomly assigned biphasic (60% HA/40% bTCP or monophasic (100% bTCP SHB without or with addition of aPRF. 109 implants were inserted into the augmented sites after 8.3 months and the insertion-torque-value (ITV measured as clinical expression of the (biomechanical stability of the augmented bone and compared to ITVs of a prior study in sinus lifting. Results. Significant better results of (biomechanical stability almost by two-fold, expressed by higher ITVs compared to native bone, were achieved with the used biomaterials and more constant results with the addition of aPRF. Conclusion. The use of SHB alone or combined with aPRF seems to be favourable to achieve a superior (biomechanical stable restored alveolar bone.

  13. LUMBAR SPINAL STENOSIS. A REVIEW OF BIOMECHANICAL STUDIES

    Institute of Scientific and Technical Information of China (English)

    戴力扬; 徐印坎

    1998-01-01

    ObjectS. To investigate the biomechanical aspects of etiology, pathology, clinical manifestation, diagnosis and surgical treatment of the lumbar spinal stenosis. Methods. A series of biomechanical methods, such as three-dimensional finite element models, threedimensional kinematic measurement, cadeveric evaluation, and imaging assessment was applied to correlate lumbar biomechanics and lumber spinal stenosls. Surgery of lumber spinal stenosis has been improved. Results.The stresses significantly concentrate on the posterolateral part of the annulus fibrcsms of disc, the posterior surface of vertebral body, the pedlcle, the interarticularis and the beet joints. This trend is intensified by disc degeneration and lumber backward extension. Posterior elcxnent resection has a definite effect upon the biomechanical behavior of lumbar vertebrae. The improved operations proved satisfactory. Conclusion. Stress concentration in the lumber vertebrae is of importance to the etiology of degenerative lumbar spinal stenosls, and disc degeneratkm is the initial key of this process. Than these will be aggravatnd by backward extension. Functloval radiography and myelography are of assistance to the diagnosis of the lumhar spinal stenosls. For the surgcal treatment of the lumber spinal stenosis, destruction of the posterior element should be avoid as far as possible based upon the thorough decmnpression. Maintaining the lumbar spine in flexion by fusion after decorapression has been proved a useftd method. When developmental spinal stenoals is combined with disc herniation, discectoray through laminotomy is recommend for decompression.

  14. Research Techniques in Biomechanics.

    Science.gov (United States)

    Ward, Terry

    Biomechanics involves the biological human beings interacting with his/her mechanical environment. Biomechanics research is being done in connection with sport, physical education, and general motor behavior, and concerns mechanics independent of implements. Biomechanics research falls in the following two general categories: (1) that specific…

  15. Determination of pre-impact occupant postures and analysis of consequences on injury outcome--part II: biomechanical study.

    Science.gov (United States)

    Hault-Dubrulle, Audrey; Robache, Frederic; Drazetic, Pascal; Guillemot, Herve; Morvan, Herve

    2011-01-01

    This paper considers pre-impact vehicle maneuvers and analyzes the resulting driver motion from their comfort seating position. Part I of this work consisted of analyzing the driver behavior during a simulated crash in a car driving simulator. The configuration of the virtual accident led to an unavoidable frontal crash with a truck. The typical response to this type of emergency event was to brace rearward into the seat and to straighten the arms against the steering wheel, or, to swerve to attempt to avoid the impacting vehicle. In a turn crossover maneuvers, the forearm is directly positioned on the airbag module at time of crash. This position represents a potential injurious situation and is investigated in this Part II. Static airbag-deployment tests were realized in collaboration with Zodiac using conventional airbag (sewn cushion, pyrotechnical system and open event) and a Hybrid III 50th Male Dummy seated with the left arm positioned in the path of the deploying airbag. These experiments were numerically reproduced with Madymo and the ellipsoid Hybrid III dummy model. The dummy arm interaction with airbag was correlated with experiments. Then, a numerical simulation of a frontal collision at 56 km/h was realized. The results of the computational runs put forward injurious situations when the driver's arm was in front of the steering wheel. Indeed, in this case, the arm could hit the head under airbag deployment and induced serious neck bending and violent head launching. To mitigate head and neck trauma in this out-of-position situation, an airbag prototype (bonded cushion, two pure helium cold gas generators allowing mono- or multi-stage inflating, patented silicone membrane) was proposed by Zodiac. The results of static airbag-deployment tests with conventional and prototype airbags showed a significant reduction of the maximum linear head acceleration and neck bending with airbag prototype when a dual stage inflating was ignited, due to a reduced

  16. Laser Metrology In Biomechanics

    Science.gov (United States)

    Pryputniewicz, Ryszard J.

    1983-12-01

    Modern treatment of sceletal disharmonies and malocclusions utilizes application of external forces. In order to effectively use these therapeutic forces, knowledge of three-dimensional displacements of bones with correlation to biological changes is required. In the past, this problem has been studied in a number of ways using, for example, strain gauges, brittle coatings, photoelasticity, as well as clinical observations and mathematical modeling. Becouse of their inherent limitations, these techniques did not always provide all the information necessary for development of meaningful relationships between the applied force system and the resulting biological remodeling. However, recent advances in the field of la-ser metrology allowed to overcome some of the dificulties found in the earlier methods and permitted development of new techniques for non-invasive measurements of bone motions in three-dimensional space. These laser techniques are particularly useful in biomechanics because they provide for rapid and accurate determination of displacements over the entire surface of the investigate object. In this paper, application of laser techniques for quantitative in-vivo and in-vitro measurements in biomechanics will be discussed and illustrated with representative examples.

  17. Immunology and Homeopathy. 4. Clinical Studies—Part 1

    OpenAIRE

    Giovanni Benato; Valeria Piasere; Francesco Pontarollo; Riccardo Ortolani; Paolo Bellavite; Anita Conforti

    2006-01-01

    The evidence-based research of the effectiveness of homeopathic medicines in common immunologic disorders is reviewed. In part 1, we introduce methodological issues of clinical research in homeopathy, and criteria utilized to evaluate the literature. Then 24 studies (12 randomized and 12 non-randomized) on common upper respiratory tract infections and otorhinolaryngologic complaints are described. In part 2, the focus will be on allergic diseases and the effectiveness of homeopathy will be gl...

  18. The use of bone age in clinical practice - Part 1

    DEFF Research Database (Denmark)

    Martin, D.D.; Caliebe, J.; Binder, Gitte Sommer;

    2011-01-01

    This review examines the role of skeletal maturity ('bone age', BA) assessment in clinical practice. BA is mainly used in children with the following conditions: short stature (addressed in part 1 of this review), tall stature, early or late puberty, and congenital adrenal hyperplasia (all...

  19. Transition questions in clinical practice - validity and reproducibility

    DEFF Research Database (Denmark)

    Lauridsen, Henrik Hein

    2008-01-01

    Transition questions in CLINICAL practice - validity and reproducibility Lauridsen HH1, Manniche C3, Grunnet-Nilsson N1, Hartvigsen J1,2 1   Clinical Locomotion Science, Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark. e-mail: hlauridsen......@health.sdu.dk 2   Nordic Institute of Chiropractic and Clinical Biomechanics, Part of Clinical Locomotion Science, Odense, Denmark 3   Backcenter Funen, Part of Clinical Locomotion Science, Ringe, Denmark   Abstract  Understanding a change score is indispensable for interpretation of results from clinical studies...

  20. Modeling the biomechanics of fetal movements.

    Science.gov (United States)

    Verbruggen, Stefaan W; Loo, Jessica H W; Hayat, Tayyib T A; Hajnal, Joseph V; Rutherford, Mary A; Phillips, Andrew T M; Nowlan, Niamh C

    2016-08-01

    Fetal movements in the uterus are a natural part of development and are known to play an important role in normal musculoskeletal development. However, very little is known about the biomechanical stimuli that arise during movements in utero, despite these stimuli being crucial to normal bone and joint formation. Therefore, the objective of this study was to create a series of computational steps by which the forces generated during a kick in utero could be predicted from clinically observed fetal movements using novel cine-MRI data of three fetuses, aged 20-22 weeks. A custom tracking software was designed to characterize the movements of joints in utero, and average uterus deflection of [Formula: see text] mm due to kicking was calculated. These observed displacements provided boundary conditions for a finite element model of the uterine environment, predicting an average reaction force of [Formula: see text] N generated by a kick against the uterine wall. Finally, these data were applied as inputs for a musculoskeletal model of a fetal kick, resulting in predicted maximum forces in the muscles surrounding the hip joint of approximately 8 N, while higher maximum forces of approximately 21 N were predicted for the muscles surrounding the knee joint. This study provides a novel insight into the closed mechanical environment of the uterus, with an innovative method allowing elucidation of the biomechanical interaction of the developing fetus with its surroundings. PMID:26534772

  1. Biomechanics principles and practices

    CERN Document Server

    Peterson, Donald R

    2014-01-01

    Presents Current Principles and ApplicationsBiomedical engineering is considered to be the most expansive of all the engineering sciences. Its function involves the direct combination of core engineering sciences as well as knowledge of nonengineering disciplines such as biology and medicine. Drawing on material from the biomechanics section of The Biomedical Engineering Handbook, Fourth Edition and utilizing the expert knowledge of respected published scientists in the application and research of biomechanics, Biomechanics: Principles and Practices discusses the latest principles and applicat

  2. Immunology and Homeopathy. 4. Clinical Studies—Part 2

    OpenAIRE

    Anita Conforti; Giovanni Benato; Valeria Piasere; Francesco Pontarollo; Riccardo Ortolani; Paolo Bellavite

    2006-01-01

    The clinical studies on the effectiveness of homeopathy in respiratory allergy (18 randomized trials and 9 observational studies) are described. The literature of common immunologic disorders including also upper respiratory tract infections (URTI) and otorhinolaryngology (reported in part 1), is evaluated and discussed. Most of initial evidence-based research was addressed to the question of whether homeopathic high dilutions are placebos or possess specific effects, but this question has be...

  3. Gingival Recessions and Biomechanics

    DEFF Research Database (Denmark)

    Laursen, Morten Godtfredsen

    Gingival recessions and biomechanics “Tissue is the issue, but bone sets the tone.“ A tooth outside the cortical plate can result in loss of bone and development of a gingival recession. The presentation aims to show biomechanical considerations in relation to movement of teeth with gingival...... by moving the root back in the alveolus. The tooth movement is accompanied by bone gain and thus increase the success rate for soft tissue augmentation. The choice of biomechanical system influences the treatment outcome. If a standard straight wire appliance is used, a biomechanical dilemma can arise...

  4. Recent microfluidic devices for studying gamete and embryo biomechanics.

    Science.gov (United States)

    Lai, David; Takayama, Shuichi; Smith, Gary D

    2015-06-25

    The technical challenges of biomechanic research such as single cell analysis at a high monetary cost, labor, and time for just a small number of measurements is a good match to the strengths of microfluidic devices. New scientific discoveries in the fertilization and embryo development process, of which biomechanics is a major subset of interest, is crucial to fuel the continual improvement of clinical practice in assisted reproduction. The following review will highlight some recent microfluidic devices tailored for gamete and embryo biomechanics where biomimicry arises as a major theme of microfluidic device design and function, and the application of fundamental biomechanic principles are used to improve outcomes of cryopreservation. PMID:25801423

  5. Biomecânica de quatro técnicas de fixação da fratura em quatro partes da cabeça umeral Biomechanics of four techniques for fixation of the four-part humeral head fracture

    Directory of Open Access Journals (Sweden)

    Elpídio da Graça

    2013-02-01

    Full Text Available OBJETIVO: Realizar um estudo biomecânico de quatro técnicas de fixação das fraturas em quatro partes da cabeça umeral. MÉTODOS: A fratura foi reproduzida em 40 úmeros plásticos, divididos em grupos de dez conforme a técnica de fixação, cada uma delas empregando diferentes recursos de fixação, em configurações distintas. Os modelos umerais foram montados em uma escápula de alumínio, com tiras de couro mimetizando os tendões do capuz rotador, e submetidos a ensaios de encurvamento e de torção em uma máquina universal de ensaios, usando a rigidez relativa como parâmetro de avaliação. Montagens com o úmero intacto foram analisadas para comparação. RESULTADOS: O comportamento biomecânico das técnicas de fixação variou dentro de uma ampla faixa, as montagens incluindo a placa DCP e os parafusos de 4,5mm de diâmetro sendo significantemente mais rígidos do que as montagens com os fios de Kirschner e os parafusos 3,5 mm de diâmetro. CONCLUSÃO: As quatro técnicas foram capazes de suportar cargas compatíveis com a demanda fisiológica, mas aquelas com a maior rigidez relativa devem ser as preferidas para finalidades clínicas. Trabalho experimental.OBJECTIVE: To carry out a biomechanical study of four techniques for fixation of four-part humeral head fractures. METHODS: The fracture was reproduced in 40 plastic humeri, divided into groups of ten according to the fixation technique, each one employing different fixation resources, in different configurations. The humeral models were mounted on an aluminum scapula, with leather straps simulating the rotator cuff tendons, and submitted to bending and torsion tests in a universal testing machine, using relative stiffness as an evaluation parameter. Assemblies with intact humeri were analyzed for comparison. RESULTS: The biomechanical behavior of the fixation techniques varied within a wide range, where the assemblies including the DCP plate and the 4.5mm diameter screws

  6. The clinical significance and management of microleakage. Part two.

    Science.gov (United States)

    Larson, Thomas D

    2005-01-01

    This research reviews relevant articles related to microleakage from 1966 to the present. The review discusses what the sensation of microleakage is clinically; how dentin permeability is related to microleakage; how the quality of dentin affects permeability and microleakage; what the effects of bacterial infiltration from microleakage can be, as well as the body's defenses against bacterial infiltration within the tooth complex; how caries and microleakage are related; and how various materials and procedures can be used to limit microleakage. Part Two reviews the use of materials, technique, and procedures to limit microleakage, and specifically how the use of various dentin and enamel bonding materials can be used to limit microleakage. PMID:15934228

  7. Computational modeling in biomechanics

    CERN Document Server

    Mofrad, Mohammad

    2010-01-01

    This book provides a glimpse of the diverse and important roles that modern computational technology is playing in various areas of biomechanics. It includes unique chapters on ab initio quantum mechanical, molecular dynamic and scale coupling methods..

  8. Biomechanics of the brain

    CERN Document Server

    Miller, Karol

    2011-01-01

    With contributions from scientists at major institutions, this book presents an introduction to brain anatomy for engineers and scientists. It provides, for the first time, a comprehensive resource in the field of brain biomechanics.

  9. Biomechanical analysis of a new carbon fiber/flax/epoxy bone fracture plate shows less stress shielding compared to a standard clinical metal plate.

    Science.gov (United States)

    Bagheri, Zahra S; Tavakkoli Avval, Pouria; Bougherara, Habiba; Aziz, Mina S R; Schemitsch, Emil H; Zdero, Radovan

    2014-09-01

    Femur fracture at the tip of a total hip replacement (THR), commonly known as Vancouver B1 fracture, is mainly treated using rigid metallic bone plates which may result in "stress shielding" leading to bone resorption and implant loosening. To minimize stress shielding, a new carbon fiber (CF)/Flax/Epoxy composite plate has been developed and biomechanically compared to a standard clinical metal plate. For fatigue tests, experiments were done using six artificial femurs cyclically loaded through the femoral head in axial compression for four stages: Stage 1 (intact), stage 2 (after THR insertion), stage 3 (after plate fixation of a simulated Vancouver B1 femoral midshaft fracture gap), and stage 4 (after fracture gap healing). For fracture fixation, one group was fitted with the new CF/Flax/Epoxy plate (n = 3), whereas another group was repaired with a standard clinical metal plate (Zimmer, Warsaw, IN) (n = 3). In addition to axial stiffness measurements, infrared thermography technique was used to capture the femur and plate surface stresses during the testing. Moreover, finite element analysis (FEA) was performed to evaluate the composite plate's axial stiffness and surface stress field. Experimental results showed that the CF/Flax/Epoxy plated femur had comparable axial stiffness (fractured = 645 ± 67 N/mm; healed = 1731 ± 109 N/mm) to the metal-plated femur (fractured = 658 ± 69 N/mm; healed = 1751 ± 39 N/mm) (p = 1.00). However, the bone beneath the CF/Flax/Epoxy plate was the only area that had a significantly higher average surface stress (fractured = 2.10 ± 0.66 MPa; healed = 1.89 ± 0.39 MPa) compared to bone beneath the metal plate (fractured = 1.18 ± 0.93 MPa; healed = 0.71 ± 0.24 MPa) (p FEA bone surface stresses yielded peak of 13 MPa at distal epiphysis (stage 1), 16 MPa at distal epiphysis (stage 2), 85 MPa for composite and 129 MPa for metal

  10. Understanding the biomechanical nature of musculoskeletal tissue.

    Science.gov (United States)

    Karduna, Andrew R

    2012-01-01

    This article provides a general overview of the biomechanical principles associated with hand therapy. Specifically, it reviews the basic topics of material properties (including both theoretical principles and practical concepts), static analysis (including forces, moments, muscle forces, and Newton's laws), and ends with a clinical example involving analysis of the risk of damage to the A3 pulley. PMID:22507212

  11. Inter-assessor reliability of practice based biomechanical assessment of the foot and ankle

    Directory of Open Access Journals (Sweden)

    Jarvis Hannah L

    2012-06-01

    Full Text Available Abstract Background There is no consensus on which protocols should be used to assess foot and lower limb biomechanics in clinical practice. The reliability of many assessments has been questioned by previous research. The aim of this investigation was to (i identify (through consensus what biomechanical examinations are used in clinical practice and (ii evaluate the inter-assessor reliability of some of these examinations. Methods Part1: Using a modified Delphi technique 12 podiatrists derived consensus on the biomechanical examinations used in clinical practice. Part 2: Eleven podiatrists assessed 6 participants using a subset of the assessment protocol derived in Part 1. Examinations were compared between assessors. Results Clinicians choose to estimate rather than quantitatively measure foot position and motion. Poor inter-assessor reliability was recorded for all examinations. Intra-class correlation coefficient values (ICC for relaxed calcaneal stance position were less than 0.23 and were less than 0.14 for neutral calcaneal stance position. For the examination of ankle joint dorsiflexion, ICC values suggest moderate reliability (less than 0.61. The results of a random effects ANOVA highlight that participant (up to 5.7°, assessor (up to 5.8° and random (up to 5.7° error all contribute to the total error (up to 9.5° for relaxed calcaneal stance position, up to 10.7° for the examination of ankle joint dorsiflexion. Kappa Fleiss values for categorisation of first ray position and mobility were less than 0.05 and for limb length assessment less than 0.02, indicating slight agreement. Conclusion Static biomechanical assessment of the foot, leg and lower limb is an important protocol in clinical practice, but the key examinations used to make inferences about dynamic foot function and to determine orthotic prescription are unreliable.

  12. Competitive bidding for Medicare Part B clinical laboratory services.

    Science.gov (United States)

    Kautter, John; Pope, Gregory C

    2014-06-01

    The traditional Medicare fee-for-service program may be able to purchase clinical laboratory test services at a lower cost through competitive bidding. Demonstrations of competitive bidding for clinical laboratory tests have been twice mandated or authorized by Congress but never implemented. This article provides a summary and review of the final design of the laboratory competitive bidding demonstration mandated by the Medicare Modernization Act of 2003. The design was analogous to a sealed bid (first price), clearing price auction. Design elements presented include covered laboratory tests and beneficiaries, laboratory bidding and payment status under the demonstration, composite bids, determining bidding winners and the demonstration fee schedule, and quality under the demonstration. Expanded use of competitive bidding in Medicare, including specifically for clinical laboratory tests, has been recommended in some proposals for Medicare reform. The presented design may be a useful point of departure if Medicare clinical laboratory competitive bidding is revived in the future. PMID:24366366

  13. Patient-Specific Models of Cardiac Biomechanics

    OpenAIRE

    Krishnamurthy, Adarsh; Villongco, Christopher T.; Chuang, Joyce; Frank, Lawrence R.; Nigam, Vishal; Belezzuoli, Ernest; Stark, Paul; Krummen, David E; Narayan, Sanjiv; Omens, Jeffrey H.; McCulloch, Andrew D.; Kerckhoffs, Roy CP

    2012-01-01

    Patient-specific models of cardiac function have the potential to improve diagnosis and management of heart disease by integrating medical images with heterogeneous clinical measurements subject to constraints imposed by physical first principles and prior experimental knowledge. We describe new methods for creating three-dimensional patient-specific models of ventricular biomechanics in the failing heart. Three-dimensional bi-ventricular geometry is segmented from cardiac CT images at end-di...

  14. Biomechanics of Rowing

    Science.gov (United States)

    Hase, Kazunori; Andrews, Brian J.; Zavatsky, Amy B.; Halliday, Suzanne E.

    A new control model for the study of biomechanical simulation of human movement was investigated using rowing as an example. The objectives were to explore biological and mechanical alternatives to optimal control methods. The simulation methods included simple control mechanisms based on proportional and derivative (PD) control, consideration of a simple neural model, introduction of an inverse dynamics system for feedback, and computational adjustment of control parameters by using an evaluative criterion and optimization method. By using simulation, appropriate rowing motions were synthesized. The generated rowing motion was periodic, continuous, and adaptable so that the pattern was stable against the mechanical force and independent of the initial condition. We believe that the simulation model is not only practical as a computational research tool from a biomechanical-engineering viewpoint but also significant from the point of view of fundamental biological theories of movement.

  15. The clinical significance and management of microleakage. Part one.

    Science.gov (United States)

    Larson, Thomas D

    2005-01-01

    This research reviews relevant articles related to microleakage from 1966 to the present. The review discusses what the sensation of microleakage is clinically; how dentin permeability is related to microleakage; how the quality of dentin affects permeability and microleakage; what the effects of bacterial infiltration from microleakage can be, as well as the body's defenses against bacterial infiltration within the tooth complex; how caries and microleakage are related; and how various materials and procedures can be used to limit microleakage. PMID:15807140

  16. Update on prolactinomas. Part 1: Clinical manifestations and diagnostic challenges.

    Science.gov (United States)

    Wong, Anni; Eloy, Jean Anderson; Couldwell, William T; Liu, James K

    2015-10-01

    The authors provide an update on the clinical manifestations and diagnostic challenges of prolactinomas. Prolactinomas are the most common pituitary adenoma seen in clinical practice. Secondary causes of hyperprolactinemia should be ruled out by assessment of the clinical history, including current medications, physical examination, pregnancy test, routine biochemical analysis with a thyroid function test, and neuroimaging, before a confirmatory diagnosis of prolactinoma is made. Prolactinomas are associated with endocrine dysfunction, affecting gonadal function and causing neurological deficits due to mass effect. The progress in elucidating the pathogenesis of prolactinomas and advances in diagnostic methods, including more sensitive diagnostic hormone assays and neuroimaging, have enriched the current diagnostic approach and management. Making the correct diagnosis is crucial to implementing the appropriate therapy. Dopamine agonist therapy remains the first line of treatment for prolactinomas, as it is effective in normalizing serum prolactin levels and reducing tumor size. Surgery is typically indicated for patients who are resistant to medical therapy or intolerant of its adverse side effects, or for those experiencing progressive neurological deficits. Nevertheless, curative surgical resection as a primary mode of treatment for smaller prolactinomas has recently gained attention as an alternative to lifelong dopamine agonist treatment. PMID:26256063

  17. Anthropometry and Biomechanics Facility

    Science.gov (United States)

    Bernal, Yaritza

    2016-01-01

    The Anthropometry and Biomechanics Facility (ABF) is equipped with anthropometric and biomechanical instrumentation and regularly performs population analysis based on analytical and modeling capabilities to test and verify if all eligible crew/passengers can be accommodated, and fitted with a protective suit that enables performance of reach and access tasks. The ABF's unique expertise can aid in identifying potential ergonomic and occupational biomechanical problems with recommended solutions to improve a suited passenger's safety, comfort, and injury protection. My involvement was in the following projects: The ABF is currently trying to define human performance capabilities in the Extravehicular Mobility Unit (EMU) space suit. Subjects are tested in an effort to further understand shoulder and elbow strength performance deficits when suited compared to unsuited. Another ongoing project is to develop a protocol to reliably characterize human health and performance metrics for individuals working inside various extravehicular activity (EVA) suits under realistic spaceflight conditions. This project will provide benchmarking data and protocols to be used in the making of future EVA suit configurations.

  18. Biomechanics of occlusion--implications for oral rehabilitation.

    Science.gov (United States)

    Peck, C C

    2016-03-01

    The dental occlusion is an important aspect of clinical dentistry; there are diverse functional demands ranging from highly precise tooth contacts to large crushing forces. Further, there are dogmatic, passionate and often diverging views on the relationship between the dental occlusion and various diseases and disorders including temporomandibular disorders, non-carious cervical lesions and tooth movement. This study provides an overview of the biomechanics of the masticatory system in the context of the dental occlusion's role in function. It explores the adaptation and precision of dental occlusion, its role in bite force, jaw movement, masticatory performance and its influence on the oro-facial musculoskeletal system. Biomechanics helps us better understand the structure and function of biological systems and consequently an understanding of the forces on, and displacements of, the dental occlusion. Biomechanics provides insight into the relationships between the dentition, jaws, temporomandibular joints, and muscles. Direct measurements of tooth contacts and forces are difficult, and biomechanical models have been developed to better understand the relationship between the occlusion and function. Importantly, biomechanical research will provide knowledge to help correct clinical misperceptions and inform better patient care. The masticatory system demonstrates a remarkable ability to adapt to a changing biomechanical environment and changes to the dental occlusion or other components of the musculoskeletal system tend to be well tolerated. PMID:26371622

  19. Statistical Analysis of Clinical Data on a Pocket Calculator, Part 2 Statistics on a Pocket Calculator, Part 2

    CERN Document Server

    Cleophas, Ton J

    2012-01-01

    The first part of this title contained all statistical tests relevant to starting clinical investigations, and included tests for continuous and binary data, power, sample size, multiple testing, variability, confounding, interaction, and reliability. The current part 2 of this title reviews methods for handling missing data, manipulated data, multiple confounders, predictions beyond observation, uncertainty of diagnostic tests, and the problems of outliers. Also robust tests, non-linear modeling , goodness of fit testing, Bhatacharya models, item response modeling, superiority testing, variab

  20. Update on Mastocytosis (Part 1): Pathophysiology, Clinical Features, and Diagnosis.

    Science.gov (United States)

    Azaña, J M; Torrelo, A; Matito, A

    2016-01-01

    Mastocytosis is a term used to describe a heterogeneous group of disorders characterized by clonal proliferation of mast cells in various organs. The organ most often affected is the skin. Mastocytosis is a relatively rare disorder that affects both sexes equally. It can occur at any age, although it tends to appear in the first decade of life, or later, between the second and fifth decades. Our understanding of the pathophysiology of mastocytosis has improved greatly in recent years, with the discovery that somatic c-kit mutations and aberrant immunophenotypic features have an important role. The clinical manifestations of mastocytosis are diverse, and skin lesions are the key to diagnosis in most patients. PMID:26546030

  1. Soft Tissue Biomechanical Modeling for Computer Assisted Surgery

    CERN Document Server

    2012-01-01

      This volume focuses on the biomechanical modeling of biological tissues in the context of Computer Assisted Surgery (CAS). More specifically, deformable soft tissues are addressed since they are the subject of the most recent developments in this field. The pioneering works on this CAS topic date from the 1980's, with applications in orthopaedics and biomechanical models of bones. More recently, however, biomechanical models of soft tissues have been proposed since most of the human body is made of soft organs that can be deformed by the surgical gesture. Such models are much more complicated to handle since the tissues can be subject to large deformations (non-linear geometrical framework) as well as complex stress/strain relationships (non-linear mechanical framework). Part 1 of the volume presents biomechanical models that have been developed in a CAS context and used during surgery. This is particularly new since most of the soft tissues models already proposed concern Computer Assisted Planning, with ...

  2. Giant cell arteritis. Part I. Terminology, classification, clinical manifestations, diagnosis

    Directory of Open Access Journals (Sweden)

    Azamat Makhmudovich Satybaldyev

    2012-09-01

    Full Text Available Giant cell arteritis (GCA is a vasculitis affecting mainly large and medium-sized arteries, which the classification of systemic vasculitides refers to as those mainly involving the large vessels. GCA is typified by the involvement of extracranial aortic branches and intracranial vessels, the aorta and its large vessels are being affected most frequently. The paper considers the terminology, classification, prevalence, major pathogenic mechanisms, and morphology of GCA. A broad spectrum of its clinical subtypes is due to target vessel stenosis caused by intimal hyperplasia. In 40% of cases, GCA is shown to be accompanied by polymyalgia rheumatica that may either precede or manifest simultaneously with GCA, or follow this disease. The menacing complications of GCA may be visual loss or ischemic strokes at various sites depending on the location of the occluded vessel. Along with the gold standard verification of the diagnosis of GCA, namely temporal artery biopsy, the author indicates other (noninvasive methods for detection of vascular lesions: color Doppler ultrasonography of the temporal arteries, fluorescein angiography of the retina, mag-netic resonance angiography, magnetic resonance imaging, and computed tomography to rule out aortic aneurysm. Dynamic 18F positron emission tomography is demonstrated to play a role in the evaluation of therapeutic effectiveness.

  3. Giant cell arteritis. Part I. Terminology, classification, clinical manifestations, diagnosis

    Directory of Open Access Journals (Sweden)

    Azamat Makhmudovich Satybaldyev

    2012-01-01

    Full Text Available Giant cell arteritis (GCA is a vasculitis affecting mainly large and medium-sized arteries, which the classification of systemic vasculitides refers to as those mainly involving the large vessels. GCA is typified by the involvement of extracranial aortic branches and intracranial vessels, the aorta and its large vessels are being affected most frequently. The paper considers the terminology, classification, prevalence, major pathogenic mechanisms, and morphology of GCA. A broad spectrum of its clinical subtypes is due to target vessel stenosis caused by intimal hyperplasia. In 40% of cases, GCA is shown to be accompanied by polymyalgia rheumatica that may either precede or manifest simultaneously with GCA, or follow this disease. The menacing complications of GCA may be visual loss or ischemic strokes at various sites depending on the location of the occluded vessel. Along with the gold standard verification of the diagnosis of GCA, namely temporal artery biopsy, the author indicates other (noninvasive methods for detection of vascular lesions: color Doppler ultrasonography of the temporal arteries, fluorescein angiography of the retina, mag-netic resonance angiography, magnetic resonance imaging, and computed tomography to rule out aortic aneurysm. Dynamic 18F positron emission tomography is demonstrated to play a role in the evaluation of therapeutic effectiveness.

  4. [Syphilis. Part 1: Introduction, pathology and clinical aspects].

    Science.gov (United States)

    Gross, G; Flaig, B; Rode, S

    2013-10-01

    In Germany more than 3,500 people become infected with syphilis annually. As elsewhere in Western Europe there is a low level endemicity with a concentration among population subgroups with high rates of partner exchange, such as men who have sex with other men. In Germany after initially reduced numbers of cases, the incidence rate has increased after the turn of the millennium. In 2011 the incidence reached 4.5 cases per 100,000 inhabitants, which is the highest incidence since the introduction of the Infection Protection Act of 2001. Syphilis, like other sexually transmitted infections and diseases with its manifold clinical manifestations and complex diagnostics, is a large global problem for public health systems. The recent resurgence of syphilis presents a challenge for all physicians but particularly for dermatologists and venereologists because the skin and adjacent mucous membranes are initially affected. Rapid diagnosis, differential diagnosis, consequent treatment and monitoring can cure the disease. Prevention of misdiagnosis is essential otherwise severe, sometimes fatal cardiovascular complications, neurosyphilis and transfer to unborn and newborn children can occur. The synergy of syphilis and sexually transmitted human immunodeficiency virus (HIV) is of special importance. Syphilis together with genital herpes and other sexually transmitted genital and oral ulcers is an important pacemaker for HIV. PMID:24150827

  5. Hypoxic preconditioning: effect, mechanism and clinical implication (Part 1).

    Science.gov (United States)

    Lu, Guo-wei; Shao, Guo

    2014-11-01

    appliances and HPC medicines such as AHFs are encouraged based on our basic research on HPC. HPC may result in therapeutic augmentation of the endogenous cytoprotection in hypoxic-ischemic or suffering from other diseases' patients. Evolutionary consideration of HPC and clinical implications of HPC are both discussed to guide future research. The product of AHF is expected to be one of the most effective first aid medicines to rescue patients in critical condition. HPC is beginning to be used in surgery and is expected to be developed into a feasible adaptive medicine in the near future. PMID:26016357

  6. Are biomechanical changes necessary for tumor progression?

    Science.gov (United States)

    Kas, Josef A.

    2014-03-01

    Already the Roman Celsus recognized rigid tissue as characteristic for solid tumors. Conversely, changes towards a weaker cytoskeleton have been described as a feature of cancer cells since the early days of tumor biology. It remains unclear if a carcinoma's rigid signature stems from more inflexible cells or is caused by the stroma. Despite that the importance of cell biomechanics for tumor progression becomes more and more evident the chicken-and-egg problem to what extent cancer cells already change their mechanical properties within the solid tumor in order to transgress its boundary or mechanical changes are induced by the microenvironment when the cell has left the tumor has been discussed highly controversial. Comprehensive clinical biomechanical measurements only exist from tumor tissue without the possibility to identify individual cells or from individual cancer cells from pleural effusions. Since the biomechanical properties of cells in carcinomas remain unknown measurements on individual cells that directly stem out of primary tumor samples are required, which we have conducted. We found in cervix and mammary carcinomas a distinctive increase of softer cells as well as contractile cells. A soft and contractile cell is like a strong elastic rope. The cell can generate a strong tensile tension to pull its self along and is soft against compression to avoid jamming.

  7. Identifying and preparing the next generation of part-time clinical teachers from dental practice.

    Science.gov (United States)

    Radford, D R; Hellyer, P; Meakin, N; Jones, K A

    2015-10-01

    Part-time general dental practitioners (GDPs) and dental care professionals (DCPs) working in practice are being increasingly utilised to deliver undergraduate clinical dental education to both dental and hygiene/therapy students. As such, there is a need for appropriate recruitment processes and ongoing staff development in the different and complex role of the clinical teacher. Recently a group of experienced dental practitioners, making a journey from GDP to part-time clinical teacher, identified common themes, experiences, challenges and realisations. These were: 'what is clinical dental education?'; 'me as a clinical teacher'; and 'specific teaching issues'. The themes highlighted the complexity of dental education and the different environment of the teaching clinic from general practice. Some of the themes identified could be a starting point for the induction process to facilitate an easier transition from experienced GDP to clinical teacher. With the current demands from both students and patients alike, the 'three way dynamic of patient, student and teacher' needs to be supported if dental schools are to attract and develop the highest quality clinical teachers. It is of critical importance to give an exceptional experience to students in their clinical education as well as to patients in terms of excellent and appropriate treatment. The challenge for deans and directors of education is to find the resources to properly fund teacher recruitment, induction and the development of part-time GDPs in order to produce the expert teachers of tomorrow. PMID:26450243

  8. The new production theory for health care through clinical reengineering: a study of clinical guidelines--Part II.

    Science.gov (United States)

    Sharp, J R

    1995-01-01

    In Part I of this two-part article, in the December 1994 issue of the journal, the author discussed the manufacturing theories of Peter Drucker in terms of their applicability for the health care field. He concluded that Drucker's four principles and practices of manufacturing--statistical quality control, manufacturing accounting, modular organization, and systems approach--do have application to the health care system. Clinical guidelines, a variation on the Drucker theory, are a specific example of the manufacturing process in health. The performance to date of some guidelines and their implications for the health care reform debate are discussed in Part II of the article. PMID:10139603

  9. Challenge-Based Instruction: The VaNTH Biomechanics Learning Modules

    Science.gov (United States)

    Barr, Ronald E.; Pandy, Marcus G.; Petrosino, Anthony J.; Roselli, Robert J.; Brophy, Sean; Freeman, Robert A.

    2007-01-01

    This paper presents the methodology and results of teaching an entire engineering course using challenge-based instruction. The challenges consisted of eight biomechanics multimedia learning modules developed by the authors as part of a broader NSF educational coalition. The biomechanics modules were presented in an undergraduate mechanical…

  10. Biomechanical conditions of walking

    CERN Document Server

    Fan, Y F; Luo, L P; Li, Z Y; Han, S Y; Lv, C S; Zhang, B

    2015-01-01

    The development of rehabilitation training program for lower limb injury does not usually include gait pattern design. This paper introduced a gait pattern design by using equations (conditions of walking). Following the requirements of reducing force to the injured side to avoid further injury, we developed a lower limb gait pattern to shorten the stride length so as to reduce walking speed, to delay the stance phase of the uninjured side and to reduce step length of the uninjured side. This gait pattern was then verified by the practice of a rehabilitation training of an Achilles tendon rupture patient, whose two-year rehabilitation training (with 24 tests) has proven that this pattern worked as intended. This indicates that rehabilitation training program for lower limb injury can rest on biomechanical conditions of walking based on experimental evidence.

  11. Systems biomechanics of the cell

    CERN Document Server

    Maly, Ivan V

    2013-01-01

    Systems Biomechanics of the Cell attempts to outline systems biomechanics of the cell as an emergent and promising discipline. The new field owes conceptually to cell mechanics, organism-level systems biomechanics, and biology of biochemical systems. Its distinct methodology is to elucidate the structure and behavior of the cell by analyzing the unintuitive collective effects of elementary physical forces that interact within the heritable cellular framework. The problematics amenable to this approach includes the variety of cellular activities that involve the form and movement of the cell body and boundary (nucleus, centrosome, microtubules, cortex, and membrane). Among the elementary system effects in the biomechanics of the cell, instability of symmetry, emergent irreversibility, and multiperiodic dissipative motion can be noted. Research results from recent journal articles are placed in this unifying framework. It is suggested that the emergent discipline has the potential to expand the spectrum of ques...

  12. Atraumatic extractions: a biomechanical rationale.

    Science.gov (United States)

    Misch, Carl E; Perez, Helena M

    2008-08-01

    Biomechanical aspects of force have been applied to tooth extraction for centuries. However, the mechanical advantages available to extract the teeth were primarily applied to hold the crown of the tooth, rather than help extract it. An extraction device (Physics Forceps) has been developed to apply a biomechanical rationale to the extraction process of a tooth using a class 1 lever, creep, and shear components of force. PMID:18717405

  13. Clinical competency assessment in intravenous therapy and vascular access: part 2.

    Science.gov (United States)

    Louise Hulse, Anna

    This article explores and critically evaluates clinical practice competencies as a form of assessment within post-registration nurse education, specifically relating to competence assessment of intravenous (IV) therapy. In the first article in this two-part series, 'Competency assessment in intravenous therapy and vascular access: part 1' (BJN, 22(16)), an in-depth literature review was carried out and applied to current competency assessment design. Clinical staff opinion was sought to evaluate users' opinions of this assessment method against recommended literature. The aim of both articles is to describe critically and analyse existing practice using this form of assessment, and relate other forms of assessment to IV therapy and vascular access clinical competence. A small-scale study was performed to evaluate whether clinical competency assessment is the most appropriate form of assessment of IV therapy and vascular access skills. A questionnaire was designed to assess nurse opinion in relation to advantages (positives) and disadvantages (negatives) of clinical practice competency assessment; 35 randomly selected post-registered nurses were included in the sample. Findings illustrated that clinical competency assessment is the most appropriate form for the assessment of clinical skills in IV therapy. However, recommendations were made for the possible use of Objective Structured Clinical Examination (OSCE) assessment. Furthermore, this report recommends the assessment of theory and knowledge through written exams or multiple-choice questions (MCQs) as an addition to clinical practice competence assessment for IV therapy. PMID:24067310

  14. Radiology as part of an objective structured clinical examination on clinical skills

    International Nuclear Information System (INIS)

    Introduction: An objective structured clinical examination (OSCE) assessess clinical competence in a standardised and context related manner. Compared with written tests, OSCE's are more susceptible to reliability errors because of the use of multiple cases and multiple examiners. In the pre-clinical phase of the medical curriculum of the University Medical Centre Utrecht, an OSCE is organised as a medical consult. We evaluated the radiology station. Method: Four questions were formulated: ·What is the internal consistency of the items of the radiology station? ·How do the scores on the radiology station compare with the scores on the test excluding radiology? ·How do different cases differ in scores? ·What are the differences in score between the examiners? We analysed the OSCE results of second year medical students in 2004. Results: Two hundred and sixty-five students were examined in the OSCE in 2004. Ninty-three Students were examined in the radiology station. Cronbach's alpha coefficient for the radiology station was 0.92. The average score for the radiology station was 3.8 (0.87). The average score for the test without radiology was 3.9 (0.32). The range of the average scores for the six different cases was 0.5 (3.6-4.1). The range of the average scores for the five examiners was 1.0 (3.3-4.3). Conclusion: The internal consistency of the items in the radiology station is good. The average score for the radiology station is similar to that of the other stations. The range of the scores between the different cases was relatively small. The range of the scores between the different examiners was clearly larger.

  15. Radiology as part of an objective structured clinical examination on clinical skills

    Energy Technology Data Exchange (ETDEWEB)

    Berk, I.A.H. van den, E-mail: i.a.h.van_den_berk@lumc.nl [Department of Radiology, Leiden University Medical Centre, Postbus 9600, 2300 RC Leiden (Netherlands); Ridder, J.M.M. van de, E-mail: J.M.M.vandeRidder@umcutrecht.nl [School of Medical Sciences, University Medical Centre Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands); Schaik, J.P.J. van, E-mail: J.P.J.vanSchaik@umcutrecht.nl [Department of Radiology, University Medical Centre Utrecht, Heidelberglaan 100 E01-132, 3584 CX Utrecht (Netherlands)

    2011-06-15

    Introduction: An objective structured clinical examination (OSCE) assessess clinical competence in a standardised and context related manner. Compared with written tests, OSCE's are more susceptible to reliability errors because of the use of multiple cases and multiple examiners. In the pre-clinical phase of the medical curriculum of the University Medical Centre Utrecht, an OSCE is organised as a medical consult. We evaluated the radiology station. Method: Four questions were formulated: {center_dot}What is the internal consistency of the items of the radiology station? {center_dot}How do the scores on the radiology station compare with the scores on the test excluding radiology? {center_dot}How do different cases differ in scores? {center_dot}What are the differences in score between the examiners? We analysed the OSCE results of second year medical students in 2004. Results: Two hundred and sixty-five students were examined in the OSCE in 2004. Ninty-three Students were examined in the radiology station. Cronbach's alpha coefficient for the radiology station was 0.92. The average score for the radiology station was 3.8 (0.87). The average score for the test without radiology was 3.9 (0.32). The range of the average scores for the six different cases was 0.5 (3.6-4.1). The range of the average scores for the five examiners was 1.0 (3.3-4.3). Conclusion: The internal consistency of the items in the radiology station is good. The average score for the radiology station is similar to that of the other stations. The range of the scores between the different cases was relatively small. The range of the scores between the different examiners was clearly larger.

  16. New Trends in Dental Biomechanics with Photonics Technologies

    Directory of Open Access Journals (Sweden)

    Lídia Carvalho

    2015-11-01

    Full Text Available Engineering techniques used to evaluate strain-stress fields, materials’ mechanical properties, and load transfer mechanisms, among others, are useful tools in the study of biomechanical applications. These engineering tools, as experimental and numerical ones, were imported to biomechanics, in particular in dental biomechanics, a few decades ago. Several experimental techniques have been used in dental biomechanics, like photoelasticity, ESPI (Electronic Speckle Pattern Interferometry, strain gages, and other kinds of transducers. However, these techniques have some limitations. For instance, photoelasticity and ESPI give the overall field pattern of the strain, showing the stress-strain concentration points. These methods cannot give an accurate measurement at all points. On the contrary, strain gages can be used to perform local measurements. However, as they use electrical resistances, their use is limited to perform in vivo measurements. Optical fiber sensors have already been used in dentistry, for diagnostic and therapeutic purposes, and in dental biomechanics studies. Lasers have also been used in clinical dentistry for a few decades. Other optical technologies, like optical coherence tomography (OCT, became suitable for dental practice and nowadays it is perhaps one that has had more development in dentristry, along with lasers.

  17. Computational biomechanics for medicine imaging, modeling and computing

    CERN Document Server

    Doyle, Barry; Wittek, Adam; Nielsen, Poul; Miller, Karol

    2016-01-01

    The Computational Biomechanics for Medicine titles provide an opportunity for specialists in computational biomechanics to present their latest methodologies and advancements. This volume comprises eighteen of the newest approaches and applications of computational biomechanics, from researchers in Australia, New Zealand, USA, UK, Switzerland, Scotland, France and Russia. Some of the interesting topics discussed are: tailored computational models; traumatic brain injury; soft-tissue mechanics; medical image analysis; and clinically-relevant simulations. One of the greatest challenges facing the computational engineering community is to extend the success of computational mechanics to fields outside traditional engineering, in particular to biology, the biomedical sciences, and medicine. We hope the research presented within this book series will contribute to overcoming this grand challenge.

  18. The attitudes of Australian radiography students towards the use of assistive transfer devices to reduce biomechanical stress in the clinical setting

    International Nuclear Information System (INIS)

    The duties performed by radiographers, which includes transferring patients onto and off the examination table, can increase their risk of developing back and neck pain. This study used a survey to identify the assistive transfer devices Australian radiography undergraduate students are familiar with and have had practise using in the clinical setting. It also sought to determine whether students are being encouraged by other radiographers to use these devices during clinical training and if they would conform to practicing unsafe transfers if instructed to by senior staff. Results indicated that radiography students were familiar with the majority of the surveyed assistive devices such as the Patslide and X-ray cassette slider. Many of the students were unlikely to participate in unsafe work practices and were able to provide alternative methods of transferring patients. However, some of the respondents could be coerced into participating in unsafe patient transfers. Radiographers should therefore be vigilant in refraining from practicing unsafe transfer techniques as it could lead to students believing it is acceptable and emulating these practices in the work place

  19. Judo Biomechanical Optimization

    CERN Document Server

    Sacripanti, Attilio

    2016-01-01

    In this paper, for the first time, there is comprehensively tackling the problem of biomechanical optimization of a sport of situation such as judo. Starting from the optimization of more simple sports, optimization of this kind of complex sports is grounded on a general physics tool such as the analysis of variation. The objective function is divided for static and dynamic situation of Athletes couple, and it is proposed also a sort of dynamic programming problem Strategic Optimization. A dynamic programming problem is an optimization problem in which decisions have to be taken sequentially over several time periods linked in some fashion. A strategy for a dynamic programming problem is just a contingency plan, a plan that specifies what is to be done at each stage as a function of all that has transpired up to that point. It is possible to demonstrate, under some conditions, that a Markovian optimal strategy is an optimal strategy for the dynamic programming problem under examination. At last we try to appr...

  20. Fracaso de la osteosíntesis mandibular. Consideraciones biomecánicas y tratamiento: A propósito de dos casos clínicos Mandibular osteosynthesis failure. Biomechanical and therapeutic considerations: Two clinical cases

    Directory of Open Access Journals (Sweden)

    I. Navarro

    2009-04-01

    Full Text Available Introducción: El fracaso de la osteosíntesis mandibular no es una situación frecuente. El objetivo de este artículo es determinar su etiología y esbozar su tratamiento. Material y métodos: Se presentan dos casos clínicos en los que se produjo un fracaso de la osteosíntesis y se indica su tratamiento. Discusión: Se analiza la etiología del fracaso y cómo, con la terapéutica adecuada, se consigue una regeneración ósea. Un conocimiento exacto de las características biomecánicas del sistema masticatorio, ayuda a abordar esta patología. Conclusión: Una fijación rígida con placas tipo "lock" junto a injerto esponjoso autólogo de cresta iliaca es la clave del éxito terapéutico.Introduction: Mandibular osteosynthesis failure is not common. The purpose of this article is to examine the etiology and treatment of mandibular osteosynthesis failure. Material and methods: Two clinical cases of mandibular osteosynthesis failure and its treatment are reported. Discussion: The etiology of osteosynthesis failure and bone regeneration with suitable treatment is analyzed Exact knowledge of the biomechanical characteristics of the masticatory system is useful in approaching this condition. Conclusion: Rigid fixation with locking plates and autologous grafts of iliac crest cancellous bone are the key to therapeutic success.

  1. Coordinator(a) de Servicios Clinicos. Parte I (Unidad I-IV). Parte II (Unidad V-VI). Guia. Documento de Trabajo (Clinical Services Coordinator. Part I. Units I-IV. Part II. Units V-VI. Guide. Working Document).

    Science.gov (United States)

    Puerto Rico State Dept. of Education, Hato Rey. Area for Vocational and Technical Education.

    This guide is intended for instructing secondary students in the occupation of clinical services coordinator in a hospital. The first part contains four units on the following subjects: the occupation of clinical services coordinator; interpersonal relationships; ethical/legal aspects; and communications (telephone, intercom, and others). For each…

  2. Biomechanical analysis technique choreographic movements (for example, "grand battman jete"

    Directory of Open Access Journals (Sweden)

    Batieieva N.P.

    2015-04-01

    Full Text Available Purpose : biomechanical analysis of the execution of choreographic movement "grand battman jete". Material : the study involved students (n = 7 of the department of classical choreography faculty of choreography. Results : biomechanical analysis of choreographic movement "grand battman jete" (classic exercise, obtained kinematic characteristics (path, velocity, acceleration, force of the center of mass (CM bio parts of the body artist (foot, shin, thigh. Built bio kinematic model (phase. The energy characteristics - mechanical work and kinetic energy units legs when performing choreographic movement "grand battman jete". Conclusions : It was found that the ability of an athlete and coach-choreographer analyze the biomechanics of movement has a positive effect on the improvement of choreographic training of qualified athletes in gymnastics (sport, art, figure skating and dance sports.

  3. The innovative viscoelastic CP ESP cervical disk prosthesis with six degrees of freedom: biomechanical concepts, development program and preliminary clinical experience.

    Science.gov (United States)

    Lazennec, Jean-Yves; Aaron, Alain; Ricart, Olivier; Rakover, Jean Patrick

    2016-01-01

    The viscoelastic cervical disk prosthesis ESP is an innovative one-piece deformable but cohesive interbody spacer. It is an evolution of the LP ESP lumbar disk implanted since 2006. CP ESP provides six full degrees of freedom about the three axes including shock absorbtion. The prosthesis geometry allows limited rotation and translation with resistance to motion (elastic return property) aimed at avoiding overload of the posterior facets. The rotation center can vary freely during motion. The concept of the ESP prosthesis is fundamentally different from that of the devices currently used in the cervical spine. The originality of the concept of the ESP® prosthesis led to innovative and intense testing to validate the adhesion of the viscoelastic component of the disk on the titanium endplates and to assess the mechanical properties of the PCU cushion. The preliminary clinical and radiological results with 2-year follow-up are encouraging for pain, function and kinematic behavior (range of motion and evolution of the mean centers of rotation). In this series, we did not observe device-related specific complications, misalignment, instability or ossifications. Additional studies and longer patient follow-up are needed to assess long-term reliability of this innovative implant. PMID:26341803

  4. Kinesiology/Biomechanics: Perspectives and Trends.

    Science.gov (United States)

    Atwater, Anne E.

    1980-01-01

    Past and recent developments and future directions in kinesiology and biomechanics are reviewed. Similarities and differences between these two areas are clarified. The areas of kinesiology and biomechanics have distinct unique qualities and should be treated as separate disciplines. (CJ)

  5. Biomechanics of Degenerative Spinal Disorders

    Science.gov (United States)

    Iorio, Justin A.; Jakoi, Andre M.

    2016-01-01

    The spine has several important functions including load transmission, permission of limited motion, and protection of the spinal cord. The vertebrae form functional spinal units, which represent the smallest segment that has characteristics of the entire spinal column. Discs and paired facet joints within each functional unit form a three-joint complex between which loads are transmitted. Surrounding the spinal motion segment are ligaments, composed of elastin and collagen, and joint capsules which restrict motion to within normal limits. Ligaments have variable strengths and act via different lever arm lengths to contribute to spinal stability. As a consequence of the longer moment arm from the spinous process to the instantaneous axis of rotation, inherently weaker ligaments (interspinous and supraspinous) are able to provide resistance to excessive flexion. Degenerative processes of the spine are a normal result of aging and occur on a spectrum. During the second decade of life, the intervertebral disc demonstrates histologic evidence of nucleus pulposus degradation caused by reduced end plate blood supply. As disc height decreases, the functional unit is capable of an increased range of axial rotation which subjects the posterior facet capsules to greater mechanical loads. A concurrent change in load transmission across the end plates and translation of the instantaneous axis of rotation further increase the degenerative processes at adjacent structures. The behavior of the functional unit is impacted by these processes and is reflected by changes in the stress-strain relationship. Back pain and other clinical symptoms may occur as a result of the biomechanical alterations of degeneration. PMID:27114783

  6. Biomechanics of bird flight.

    Science.gov (United States)

    Tobalske, Bret W

    2007-09-01

    Power output is a unifying theme for bird flight and considerable progress has been accomplished recently in measuring muscular, metabolic and aerodynamic power in birds. The primary flight muscles of birds, the pectoralis and supracoracoideus, are designed for work and power output, with large stress (force per unit cross-sectional area) and strain (relative length change) per contraction. U-shaped curves describe how mechanical power output varies with flight speed, but the specific shapes and characteristic speeds of these curves differ according to morphology and flight style. New measures of induced, profile and parasite power should help to update existing mathematical models of flight. In turn, these improved models may serve to test behavioral and ecological processes. Unlike terrestrial locomotion that is generally characterized by discrete gaits, changes in wing kinematics and aerodynamics across flight speeds are gradual. Take-off flight performance scales with body size, but fully revealing the mechanisms responsible for this pattern awaits new study. Intermittent flight appears to reduce the power cost for flight, as some species flap-glide at slow speeds and flap-bound at fast speeds. It is vital to test the metabolic costs of intermittent flight to understand why some birds use intermittent bounds during slow flight. Maneuvering and stability are critical for flying birds, and design for maneuvering may impinge upon other aspects of flight performance. The tail contributes to lift and drag; it is also integral to maneuvering and stability. Recent studies have revealed that maneuvers are typically initiated during downstroke and involve bilateral asymmetry of force production in the pectoralis. Future study of maneuvering and stability should measure inertial and aerodynamic forces. It is critical for continued progress into the biomechanics of bird flight that experimental designs are developed in an ecological and evolutionary context. PMID:17766290

  7. Problems of Sport Biomechanics and Robotics

    OpenAIRE

    Erdmann, Wlodzimierz S.

    2013-01-01

    This paper presents many common areas of interest of different specialists. There are problems described from sport, biomechanics, sport biomechanics, sport engineering, robotics, biomechanics and robotics, sport biomechanics and robotics. There are many approaches to sport from different sciences and engineering. Robotics is a relatively new area and has had moderate attention from sport specialists. The aim of this paper is to present several areas necessary to develop sport robots based on...

  8. Biomechanical analysis of rollator walking

    DEFF Research Database (Denmark)

    Alkjaer, T; Larsen, Peter K; Pedersen, Gitte;

    2006-01-01

    The rollator is a very popular walking aid. However, knowledge about how a rollator affects the walking patterns is limited. Thus, the purpose of the study was to investigate the biomechanical effects of walking with and without a rollator on the walking pattern in healthy subjects.......The rollator is a very popular walking aid. However, knowledge about how a rollator affects the walking patterns is limited. Thus, the purpose of the study was to investigate the biomechanical effects of walking with and without a rollator on the walking pattern in healthy subjects....

  9. Unified Approach to the Biomechanics of Dental Implantology

    Science.gov (United States)

    Grenoble, D. E.; Knoell, A. C.

    1973-01-01

    The human need for safe and effective dental implants is well-recognized. Although many implant designs have been tested and are in use today, a large number have resulted in clinical failure. These failures appear to be due to biomechanical effects, as well as biocompatibility and surgical factors. A unified approach is proposed using multidisciplinary systems technology, for the study of the biomechanical interactions between dental implants and host tissues. The approach progresses from biomechanical modeling and analysis, supported by experimental investigations, through implant design development, clinical verification, and education of the dental practitioner. The result of the biomechanical modeling, analysis, and experimental phases would be the development of scientific design criteria for implants. Implant designs meeting these criteria would be generated, fabricated, and tested in animals. After design acceptance, these implants would be tested in humans, using efficient and safe surgical and restorative procedures. Finally, educational media and instructional courses would be developed for training dental practitioners in the use of the resulting implants.

  10. Integrative Structural Biomechanical Concepts of Ankylosing Spondylitis

    Directory of Open Access Journals (Sweden)

    Alfonse T. Masi

    2011-01-01

    Full Text Available Ankylosing spondylitis (AS is not fully explained by inflammatory processes. Clinical, epidemiological, genetic, and course of disease features indicate additional host-related risk processes and predispositions. Collectively, the pattern of predisposition to onset in adolescent and young adult ages, male preponderance, and widely varied severity of AS is unique among rheumatic diseases. However, this pattern could reflect biomechanical and structural differences between the sexes, naturally occurring musculoskeletal changes over life cycles, and a population polymorphism. During juvenile development, the body is more flexible and weaker than during adolescent maturation and young adulthood, when strengthening and stiffening considerably increase. During middle and later ages, the musculoskeletal system again weakens. The novel concept of an innate axial myofascial hypertonicity reflects basic mechanobiological principles in human function, tissue reactivity, and pathology. However, these processes have been little studied and require critical testing. The proposed physical mechanisms likely interact with recognized immunobiological pathways. The structural biomechanical processes and tissue reactions might possibly precede initiation of other AS-related pathways. Research in the combined structural mechanobiology and immunobiology processes promises to improve understanding of the initiation and perpetuation of AS than prevailing concepts. The combined processes might better explain characteristic enthesopathic and inflammatory processes in AS.

  11. Expandable intramedullary nail - experimental biomechanical evaluation

    Directory of Open Access Journals (Sweden)

    A. Kajzer

    2010-01-01

    Full Text Available Purpose: The paper presents results of experimental analysis of femur and femur – expandable intramedullary nail system. The aim of the work was to determine displacement in three models. In addition, the torsion of the system aiming at determining the moments depending on the torsional angle of the bone was carried out.Design/methodology/approach: Three femurs were selected for studies. The analysis was carried out on the femur – expandable intramedullary nail system. The influence of the loads and displacements on the bone – nail system on the results of experimental analysis was analysed. In order to carry out calculations, three models were selected: model I – bone without fracture gap, model II and III – femur with expansion intramedullary nails – fracture gap was located 100 mm under greater trochanter. The studies were performed on femur models produced by Swedish company Sawbones. The intramedullary „Fixion IM” nails (Ti-6Al-4V alloy were implanted into the bone. Displacements of determinated models were being recorded from the sensors every 100 N from 10 N to 2000 N.Findings: The analyses showed the difference in displacements, depending on the selected models.Research limitations/implications: The limitations were connected with simplification of boundary conditions during analysis which were the result of the simplification of the models. While studying, muscles and ligaments supporting the bone in anatomic position were not taken into consideration. Instead, the system has been loaded with the axial force (compression.Practical implications: The obtained results can be useful in clinical practice. They can be applied in selection of stabilization methods or rehabilitation as well as in describing the biomechanical conditions connected with type of bone fracture obtained from medical imaging.Originality/value: . The work compares the values of displacement of characteristic points of femur (healthy – model I with the

  12. Características biomecânicas, ergonômicas e clínicas da postura sentada: uma revisão Biomechanic, ergonomic, and clinical features of the sitting posture: a review

    Directory of Open Access Journals (Sweden)

    Nise Ribeiro Marques

    2010-09-01

    Full Text Available A posição sentada é a mais adotada nos ambientes de trabalho, na escola e nas atividades de lazer. Porém, a manutenção prolongada dessa posição ocasiona a adoção de posturas inadequadas e sobrecarrega as estruturas do sistema musculoesquelético, o que pode acarretar dor e lesão na coluna lombar. A presente revisão teve como objetivo identificar os fatores biomecânicos, ergonômicos e clínicos envolvidos na sustentação da postura sentada. Para isso, foram consultadas as bases de dados ISI Web of Knowledge, Medline, Pubmed e EBSCO Host, sendo selecionados 72 artigos publicados entre 1965 e 2010. Foi possível identificar que na posição sentada não existe uma postura ideal a ser sustentada, mas algumas posturas são mais recomendadas do que outras, tal como a postura sentada ereta e a postura lordótica. As cadeiras influenciam o padrão da posição sentada: conforme seu design, pode permitir maior variedade de posturas. Modificações na cadeira e a utilização de exercícios para o aumento da resistência muscular e da propriocepção, bem como a reeducação postural, são intervenções úteis para reduzir o impacto causado pela posição sentada prolongada no sistema musculoesquelético.The sitting posture is the most adopted in work environment, at school and in leisure activities. However, prolonged maintenance of this position causes the adoption of inadequate postures and overloads skeletal muscle structures, which may lead to spine pain and injuries. The purpose of the present review was to identify biomechanic, ergonomic, and clinical features involved in maintenance of the sitting position. The search in ISI Web of Knowledge, Medline, Pubmed and EBSCOHost data bases led to selecting 72 articles published between 1965 and 2010. Results show that there is not an ideal posture to be kept, but some postures are more recommended than others, like the upright sitting and the lordotic postures. Chairs influence the

  13. Biomechanics of ossiculoplasty

    OpenAIRE

    Kelly, Daniel; PRENDERGAST, PATRICK JOHN

    2003-01-01

    PUBLISHED Many different designs of prostheses are available for middle ear surgery. Clinical comparisons of such prostheses are often difficult because of the large number of variables involved in the clinical outcome; including the skill of the surgeon or patient variability. In an attempt to compare the performance of four different middle ear implants (Kurz Bell-Tubingen, Kurz Aerial-Tubingen, Xomed no.0362, Xomed no. 0321), a finite element model of the middle ear befor...

  14. Biomechanical analysis of jaw-closing movements.

    Science.gov (United States)

    Koolstra, J H; van Eijden, T M

    1995-09-01

    This study concerns the complex interaction between active muscle forces and passive guiding structures during jaw-closing movements. It is generally accepted that the ligaments of the joint play a major role in condylar guidance during these movements. While these ligaments permit a wide range of motions, it was assumed that they are not primarily involved in force transmission in the joints. Therefore, it was hypothesized that muscle forces and movement constraints caused by the articular surfaces imply a necessary and sufficient condition to generate ordinary jaw-closing movements. This hypothesis was tested by biomechanical analysis. A dynamic six-degrees-of-freedom mathematical model of the human masticatory system has been developed for qualitative analysis of the contributions of the different masticatory muscles to jaw-closing movements, it was found that the normally observed movement, which includes a swing-slide condylar movement along the articular eminence, can be generated by various separate pairs of masticatory muscles, among which the different parts of the masseter as well as the medial pterygoid muscle appeared to be the most suitable to complete this action. The results seem to be in contrast to the general opinion that a muscle with a forward-directed force component may not be suitable for generating jaw movements in which the condyle moves backward. The results can be explained, however, by biomechanical analysis which includes not only muscle and joint forces as used in standard textbooks of anatomy, but also the torques generated by these forces. PMID:7560417

  15. Ideas for a phenomenological interpretation and elaboration of personal construct theory Part 3. Clinic, psychotherapy, research

    OpenAIRE

    Armezzani, Maria; Chiari, Gabriele

    2015-01-01

    In this part of our work about a comparison between Kelly's personal construct theory and phenomenology, we enter the fields of psychotherapy and research. The topic of intersubjectivity, meant as original recognition of the other's subjectivity, provides a backdrop for both phenomenological clinic and Kellyan psychotherapy. Though Kelly never used the term "intersubjectivity", his theory and the corollary of sociality in particular, reveals a view of interpersonal relationships as intercorpo...

  16. Essentials of Pediatric Emergency Medicine Fellowship: Part 4: Beyond Clinical Education.

    Science.gov (United States)

    Wolff, Margaret; Carney, Michele; Eldridge, Charles; Zaveri, Pavan; Kou, Maybelle

    2016-08-01

    This article is the third in a 7-part series that aims to comprehensively describe the current state and future directions of pediatric emergency medicine fellowship training from the essential requirements to considerations for successfully administering and managing a program to the careers that may be anticipated upon program completion. This article focuses on the skills beyond clinical training required of pediatric emergency medicine physicians including teaching, leadership, teamwork, and communication. PMID:27490731

  17. Nursing students´perception of taking part in an Inter-professional Clinical Study Unit

    DEFF Research Database (Denmark)

    Bahnsen, Iben Bøgh; Braad, Mette; Lisby, Hanne;

    2013-01-01

    Background: Length of hospitalization is reduced demanding effective and timely interventions from all health professions. In an Inter-professional Clinical Study Unit (ICSU) students have the opportunity to develop inter-professional competencies. Nevertheless some nursing students have commented...... that staying in an ICSU is an interruption in their final clinical placement with limited learning possibilities. Aim: The aim of the study was to explore nursing students´perceptions of taking part in an ICSU Methods: The study was qualitative with explorative, decriptive and interpretative aspects...... integrate the stay at ICSU in their final clinical placement. Moreover, students spent a considerable amount of time an basic nursing tasks during their stay at the ICSU; skills already acquired earlier in their education programme. Conclusion: Staying in an ICSU improved inter-professional collaboration...

  18. Changes in multi-segment foot biomechanics with a heat-mouldable semi-custom foot orthotic device

    Directory of Open Access Journals (Sweden)

    Ferber Reed

    2011-06-01

    Full Text Available Abstract Background Semi-custom foot orthoses (SCO are thought to be a cost-effective alternative to custom-made devices. However, previous biomechanical research involving either custom or SCO has only focused on rearfoot biomechanics. The purpose of this study was therefore to determine changes in multi-segment foot biomechanics during shod walking with and without an SCO. We chose to investigate an SCO device that incorporates a heat-moulding process, to further understand if the moulding process would significantly alter rearfoot, midfoot, or shank kinematics as compared to a no-orthotic condition. We hypothesized the SCO, whether moulded or non-moulded, would reduce peak rearfoot eversion, tibial internal rotation, arch deformation, and plantar fascia strain as compared to the no-orthoses condition. Methods Twenty participants had retroreflective markers placed on the right limb to represent forefoot, midfoot, rearfoot and shank segments. 3D kinematics were recorded using an 8-camera motion capture system while participants walked on a treadmill. Results Plantar fascia strain was reduced by 34% when participants walked in either the moulded or non-moulded SCO condition compared to no-orthoses. However, there were no significant differences in peak rearfoot eversion, tibial internal rotation, or medial longitudinal arch angles between any conditions. Conclusions A semi-custom moulded orthotic does not control rearfoot, shank, or arch deformation but does, however, reduce plantar fascia strain compared to walking without an orthoses. Heat-moulding the orthotic device does not have a measurable effect on any biomechanical variables compared to the non-moulded condition. These data may, in part, help explain the clinical efficacy of orthotic devices.

  19. Biomechanical model of otorhinoal ryngological organs and its clinical application%耳鼻咽喉器官结构与功能数值模拟的研究与临床应用

    Institute of Scientific and Technical Information of China (English)

    苏英锋; 孙秀珍

    2015-01-01

    Otorhinolaryngological organs, tiny sensory organs which locate deeply anatomically, contact with the external environment directly, which is closely related to the functional process and physiological process of the organs.Regarding clinical common diseases or stubborn disease as the break-through point, we extract and condense the scientific questions in the level of interdisciplinarity of science and engineering and clinical medicine, it is just like blaze another trail to ex-plore the mechanism of function implementation and the prediction and prevention of related diseases in the stimulation of outside environment through using research framework that fusion of computational biomechanics,modern informatics,com-puter technology and medical basic theory, clinical medical detection technology and establishing biological organs numeri-cal model.This paper discusses research status about ear, nose, pharynx, larynx organ biological numerical model from the two aspects of experimental study and numerical model study, and discussing the research achievements'application in the medical field,and also prospecting the research value of the current establishment of otorhinolaryngological organs biological numerical model.%耳鼻咽喉器官是人体直接接触外界环境的感觉性器官,具有解剖深在、细小之特点,其功能的实现和疾病发生与外界环境紧密相关。以临床常见或疑难疾患为切入点,从中提取和凝聚理工科与临床医学学科交叉界面的科学问题,采用计算生物力学、现代信息学和计算机技术与医学基础理论、临床医疗检测技术相融合的研究框架,建立生物器官数值模型,探索其在一定外界环境刺激下,功能实现的机理以及相关疾病的预测和防治具有另辟蹊径的意义。本文从实验研究和数值模型研究两个方面讨论了耳、鼻、咽、喉器官生物数值模型研究现状,并就其研究成果在医疗领域的应

  20. Assessment and characterization of in situ rotator cuff biomechanics

    Science.gov (United States)

    Trent, Erika A.; Bailey, Lane; Mefleh, Fuad N.; Raikar, Vipul P.; Shanley, Ellen; Thigpen, Charles A.; Dean, Delphine; Kwartowitz, David M.

    2013-03-01

    Rotator cuff disease is a degenerative disorder that is a common, costly, and often debilitating, ranging in severity from partial thickness tear, which may cause pain, to total rupture, leading to loss in function. Currently, clinical diagnosis and determination of disease extent relies primarily on subjective assessment of pain, range of motion, and possibly X-ray or ultrasound images. The final treatment plan however is at the discretion of the clinician, who often bases their decision on personal experiences, and not quantitative standards. The use of ultrasound for the assessment of tissue biomechanics is established, such as in ultrasound elastography, where soft tissue biomechanics are measured. Few studies have investigated the use of ultrasound elastography in the characterization of musculoskeletal biomechanics. To assess tissue biomechanics we have developed a device, which measures the force applied to the underlying musculotendentious tissue while simultaneously obtaining the related ultrasound images. In this work, the musculotendinous region of the infraspinatus of twenty asymptomatic male organized baseball players was examined to access the variability in tissue properties within a single patient and across a normal population. Elastic moduli at percent strains less than 15 were significantly different than those above 15 percent strain within the normal population. No significant difference in tissue properties was demonstrated within a single patient. This analysis demonstrated elastic moduli are variable across individuals and incidence. Therefore threshold elastic moduli will likely be a function of variation in local-tissue moduli as opposed to a specific global value.

  1. Trends in global clinical trial registration: an analysis of numbers of registered clinical trials in different parts of the world from 2004 to 2013

    OpenAIRE

    Viergever, R.F.; Li, K.

    2015-01-01

    OBJECTIVES: To analyse developments (and their causes) in the number and proportion of clinical trials that were registered in different parts of the world after the International Committee of Medical Journal Editors (ICMJE) announced in 2004 that it would require registration of clinical trials as a condition for publication. SETTING: The International Clinical Trials Registry Platform (ICTRP). DESIGN: The ICTRP database was searched for all clinical trials that were registered up to 31 Dece...

  2. [Biomechanics of whiplash injuries of the cervical spine].

    Science.gov (United States)

    Schmidt, G

    1989-07-01

    1. The whiplash injury of the cervical spine is a typical, but not very often observed injury of occupants of automotive vehicles involved in moderate collisions. 2. There still exist great uncertainties in the elaboration of expertises concerning the minor whiplash injury, so that the great part of the disturbances cannot be objectivated under a clinical point of view. And on the other hand, serious whiplash injuries often are superposed or veiled by secondary injuries. 3. Thus, the aim of the present paper was to point out injury mechanisms, to give a rough scaling of the whiplash severity under biomechanical aspects and finally to set these injury mechanisms in correlation to the following criteria of accident: a) vehicle velocity change (energy equivalent speed--EES); b) deformation of vehicles on the impact-exposed structure; c) loading of occupants by acceleration or deceleration. 4. The tolerance limit of the cervical spine generally decreases to a lower limit, if the cervical spine is changed in a pathological way, e.g. by preexisting diseases. 5. It is evident and important, that the difficult work of giving an expert's opinion on this field must be performed in an interdisciplinary collaboration of engineers for collision-analysis and physicians experienced in accident-traumatology. PMID:2669311

  3. Treatment of Progressive First Metatarsophalangeal Hallux Valgus Deformity: A Biomechanically Based Muscle-Strengthening Approach.

    Science.gov (United States)

    Glasoe, Ward M

    2016-07-01

    Synopsis Hallux valgus is a progressive deformity of the first metatarsophalangeal joint that changes the anatomy and biomechanics of the foot. To date, surgery is the only treatment to correct this deformity, though the recurrence rate is as high as 15%. This clinical commentary provides instruction in a strengthening approach for treatment of hallux valgus deformity, by addressing the moment actions of 5 muscles identified as having the ability to counter the hallux valgus process. Unlike surgery, muscle strengthening does not correct the deformity, but, instead, reduces the pain and associated gait impairments that affect the mobility of people who live with the disorder. This review is organized in 4 parts. Part 1 defines the terms of foot motion and posture. Part 2 details the anatomy and biomechanics, and describes how the foot is changed with deformity. Part 3 details the muscles targeted for strengthening; the intrinsics being the abductor hallucis, adductor hallucis, and the flexor hallucis brevis; the extrinsics being the tibialis posterior and fibularis longus. Part 4 instructs the exercise and reviews the related literature. Instructions are given for the short-foot, the toe-spread-out, and the heel-raise exercises. The routine may be performed by almost anyone at home and may be adopted into physical therapist practice, with intent to strengthen the foot muscles as an adjunct to almost any protocol of care, but especially for the treatment of hallux valgus deformity. J Orthop Sports Phys Ther 2016;46(7):596-605. Epub 6 Jun 2016. doi:10.2519/jospt.2016.6704. PMID:27266887

  4. Biomechanics of knee joint — A review

    Science.gov (United States)

    Madeti, Bhaskar Kumar; Chalamalasetti, Srinivasa Rao; Bolla Pragada, S. K. Sundara siva rao

    2015-06-01

    The present paper is to know how the work is carried out in the field of biomechanics of knee. Various model formulations are discussed and further classified into mathematical model, two-dimensional model and three-dimensional model. Knee geometry is a crucial part of human body movement, in which how various views of knee is shown in different planes and how the forces act on tibia and femur are studied. It leads to know the forces acting on the knee joint. Experimental studies of knee geometry and forces acting on knee shown by various researchers have been discussed, and comparisons of results are made. In addition, static and dynamic analysis of knee has been also discussed respectively to some extent.

  5. LECTURE ON ACUPUNCTURE Part I Clinical Acupuncture Lecture Thirty-four UROLITHIASIS

    Institute of Scientific and Technical Information of China (English)

    潘兴芳; 尚秀葵; 王卫

    2004-01-01

    @@ Urolithiasis is the general designation of urinary calculus occurring in every part of the urinary system, and is a commonly encountered disease in clinic. It is closely related to the environmental factors, systemic diseases and urinary diseases. It may mainly manifest lumbo-abdominal angina and hematuria, or be accompanied by symptoms of urinary obstruction and infection such as frequent and urgent micturition, urodynia, etc.. Urolithiasis corresponds to Shalin (砂淋 stranguria caused by urinary stones) or Xuelin (血淋 stranguria with blood) in TCM.

  6. Extracranial diffusion-weighted imaging. Clinical applications - abdomen, thorax, soft tissue and bone marrow Part II

    International Nuclear Information System (INIS)

    In the first part of the article the basic physical principles of DWI were considered together with sequence optimization in the extracranial applications of this imaging technic. Clinical application of DWI in general were discussed. A more detailed review of the application of DWI in focal and diffuse liver diseases was offered. This article will focus in detail on the application of DWI and the changes in DWI images in the pathological processes involving the gallbladder and bile ducts, pancreas, kidneys, adrenals, spleen, lymph nodes, large blood vessels, Gl tract, thorax, musculo-skeletal system and soft tissues. Key words: EXTRACRANIAL DIFFUSION. DWI. MRI

  7. Sport and Exercise Biomechanics (Bios Instant Notes)

    OpenAIRE

    Paul Grimshaw; Adrian Lees; Neil Fowler; Adrian Burden

    2007-01-01

    DESCRIPTION Instant Notes on Sport and Exercise Biomechanics provides a broad overview of the fundamental concepts in exercise and sport biomechanics. PURPOSE The book aims to provide instant notes on essential information about biomechanics, and is designed to help undergraduate students to grasp the corresponding subjects in physical effort rapidly and easily. AUDIENCE The book provides a useful resource for undergraduate and graduate students as a fundamental reference book. For the resear...

  8. A 5-year PICU experience of disseminated staphylococcal disease, part 1: clinical and microbial profile.

    Science.gov (United States)

    Baranwal, Arun K; Singhi, Sunit C; Jayashree, M

    2007-08-01

    metastatic foci by thorough clinical evaluation, appropriate and frequent imaging studies form an integral part of management. PMID:17478541

  9. Biomechanical Evaluation of 6.5-mm Cannulated Screws.

    Science.gov (United States)

    Taylor, Benjamin C; Litsky, Alan S; Pugh, Kevin J; Fowler, T Ty

    2016-01-01

    Although biomechanical and clinical evidence exists regarding smaller compression screws, biomechanical data regarding the larger headless screws are not currently available. Headed and headless 6.5-mm cannulated compression screws were examined, with analysis of interfragmentary compression, insertion torque, and resistance of the construct to a shear force. No significant differences were seen between the maximum insertion torque of the headless or headed screws. Maximum and steady-state compression forces were also not significantly different between groups. Countersinking the headless model 2 mm led to a 77.01% decrease in steady-state compression levels. Shear testing did not reveal any significant differences in peak load at ultimate failure, specimen stiffness, or final block displacement, although a trend to increased peak load and stiffness was seen with the headless specimens. PMID:27082882

  10. [Advances on biomechanics and kinematics of sprain of ankle joint].

    Science.gov (United States)

    Zhao, Yong; Wang, Gang

    2015-04-01

    Ankle sprains are orthopedic clinical common disease, accounting for joint ligament sprain of the first place. If treatment is not timely or appropriate, the joint pain and instability maybe develop, and even bone arthritis maybe develop. The mechanism of injury of ankle joint, anatomical basis has been fully study at present, and the diagnostic problem is very clear. Along with the development of science and technology, biological modeling and three-dimensional finite element, three-dimensional motion capture system,digital technology study, electromyographic signal study were used for the basic research of sprain of ankle. Biomechanical and kinematic study of ankle sprain has received adequate attention, combined with the mechanism research of ankle sprain,and to explore the the biomechanics and kinematics research progress of the sprain of ankle joint. PMID:26072625

  11. Biomechanical properties of four dermal substitutes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guo-an; NING Fang-gang; ZHAO Nan-ming

    2007-01-01

    @@ Many kinds of cell-free dermal substitutes have been developed during the past several years, however,their biomechanical properties, including hysteresis,stress relaxation, creep, and non-linear stress-strain, are still unknown. In this study, we tested these biomechanical characteristics of four dermal substitutes,and compared them with those of fresh human skin (FHS).

  12. Applied Biomechanics in an Instructional Setting

    Science.gov (United States)

    Hudson, Jackie L.

    2006-01-01

    Biomechanics is the science of how people move better, meaning more skillfully and more safely. This article places more emphasis on skill rather than safety, though there are many parallels between them. It shares a few features of the author's paradigm of applied biomechanics and discusses an integrated approach toward a middle school football…

  13. Mechatronic support of present robotics and biomechanics

    Czech Academy of Sciences Publication Activity Database

    Ehrenberger, Zdeněk; Kratochvíl, Ctirad; Janíček, P.

    Brno: VUT, 2003 - (Ehrenberger, Z.; Houfek, L.; Kratochvíl, C.), s. 1-2 ISBN 80-21423-12-9. [Mechanotronic, Robotics and biomechanics 2003. Hrotovice (CZ), 24.03.2003-27.03.2003] Institutional research plan: CEZ:AV0Z2076919 Keywords : mechatronics * robotics * biomechanics Subject RIV: JD - Computer Applications, Robotics

  14. Biomechanic evaluation and clinical efficacy of RTS minimally invasive spine system%RTS自旋转撑开脊柱微创内固定系统的生物力学研究及临床疗效评价

    Institute of Scientific and Technical Information of China (English)

    赵泉来; 李逸峰; 俞宏星; 徐宏光; 沈祥; 王弘; 刘平; 王凌挺; 杨晓明; 陈学武; 张玙

    2015-01-01

    postoperative distraction, reset, loss of correc-tion. Objective:To assess the biomechanics and clinical efficacy of RTS minimally invasive spine system for thoracolumbar frac-ture. Methods:Mid-column thoracolumbar fracture was made in 5 fresh calves. Meanwhile, 52 patients with thoracolumbar frac-ture were enrolled in this study and divided into 2 groups:RTS group (n=27) and open surgery group (n=23). Surgical inci-sion, operation time, blood loss and deformity correction were recorded and compared between two groups. Results:There were no significant differences in the slip distances of extension experiment or torsion experiment between internal fixation group and control group. However, there were no significant differences in the slip distances of axial com-pression experiment or flexion experiment between these two groups. The maximum axial pull output of short screw (6.5 mm×30 mm) was 58.4%of long screw (6.5 mm×50 mm). There were significant differences in the incision size, operation duration, intraoperative blood loss, postoperative draining and postoperative VAS score between the RTS group and open surgery group (P the pain and recover the spinal function. With its minor surgical trauma, the RTS minimally invasive spine system can be used in clinic further.

  15. A diagnosis-based clinical decision rule for spinal pain part 2: review of the literature

    Directory of Open Access Journals (Sweden)

    Hurwitz Eric L

    2008-08-01

    Full Text Available Abstract Background Spinal pain is a common and often disabling problem. The research on various treatments for spinal pain has, for the most part, suggested that while several interventions have demonstrated mild to moderate short-term benefit, no single treatment has a major impact on either pain or disability. There is great need for more accurate diagnosis in patients with spinal pain. In a previous paper, the theoretical model of a diagnosis-based clinical decision rule was presented. The approach is designed to provide the clinician with a strategy for arriving at a specific working diagnosis from which treatment decisions can be made. It is based on three questions of diagnosis. In the current paper, the literature on the reliability and validity of the assessment procedures that are included in the diagnosis-based clinical decision rule is presented. Methods The databases of Medline, Cinahl, Embase and MANTIS were searched for studies that evaluated the reliability and validity of clinic-based diagnostic procedures for patients with spinal pain that have relevance for questions 2 (which investigates characteristics of the pain source and 3 (which investigates perpetuating factors of the pain experience. In addition, the reference list of identified papers and authors' libraries were searched. Results A total of 1769 articles were retrieved, of which 138 were deemed relevant. Fifty-one studies related to reliability and 76 related to validity. One study evaluated both reliability and validity. Conclusion Regarding some aspects of the DBCDR, there are a number of studies that allow the clinician to have a reasonable degree of confidence in his or her findings. This is particularly true for centralization signs, neurodynamic signs and psychological perpetuating factors. There are other aspects of the DBCDR in which a lesser degree of confidence is warranted, and in which further research is needed.

  16. Biomechanical analysis of the camelid cervical intervertebral disc

    Directory of Open Access Journals (Sweden)

    Dean K. Stolworthy

    2015-01-01

    Full Text Available Chronic low back pain (LBP is a prevalent global problem, which is often correlated with degenerative disc disease. The development and use of good, relevant animal models of the spine may improve treatment options for this condition. While no animal model is capable of reproducing the exact biology, anatomy, and biomechanics of the human spine, the quality of a particular animal model increases with the number of shared characteristics that are relevant to the human condition. The purpose of this study was to investigate the camelid (specifically, alpaca and llama cervical spine as a model of the human lumbar spine. Cervical spines were obtained from four alpacas and four llamas and individual segments were used for segmental flexibility/biomechanics and/or morphology/anatomy studies. Qualitative and quantitative data were compared for the alpaca and llama cervical spines, and human lumbar specimens in addition to other published large animal data. Results indicate that a camelid cervical intervertebral disc (IVD closely approximates the human lumbar disc with regard to size, spinal posture, and biomechanical flexibility. Specifically, compared with the human lumbar disc, the alpaca and llama cervical disc size are approximately 62%, 83%, and 75% with regard to area, depth, and width, respectively, and the disc flexibility is approximately 133%, 173%, and 254%, with regard to range of motion (ROM in axial-rotation, flexion-extension, and lateral-bending, respectively. These results, combined with the clinical report of disc degeneration in the llama lower cervical spine, suggest that the camelid cervical spine is potentially well suited for use as an animal model in biomechanical studies of the human lumbar spine.

  17. A review of biomechanically informed breast image registration

    Science.gov (United States)

    Hipwell, John H.; Vavourakis, Vasileios; Han, Lianghao; Mertzanidou, Thomy; Eiben, Björn; Hawkes, David J.

    2016-01-01

    Breast radiology encompasses the full range of imaging modalities from routine imaging via x-ray mammography, magnetic resonance imaging and ultrasound (both two- and three-dimensional), to more recent technologies such as digital breast tomosynthesis, and dedicated breast imaging systems for positron emission mammography and ultrasound tomography. In addition new and experimental modalities, such as Photoacoustics, Near Infrared Spectroscopy and Electrical Impedance Tomography etc, are emerging. The breast is a highly deformable structure however, and this greatly complicates visual comparison of imaging modalities for the purposes of breast screening, cancer diagnosis (including image guided biopsy), tumour staging, treatment monitoring, surgical planning and simulation of the effects of surgery and wound healing etc. Due primarily to the challenges posed by these gross, non-rigid deformations, development of automated methods which enable registration, and hence fusion, of information within and across breast imaging modalities, and between the images and the physical space of the breast during interventions, remains an active research field which has yet to translate suitable methods into clinical practice. This review describes current research in the field of breast biomechanical modelling and identifies relevant publications where the resulting models have been incorporated into breast image registration and simulation algorithms. Despite these developments there remain a number of issues that limit clinical application of biomechanical modelling. These include the accuracy of constitutive modelling, implementation of representative boundary conditions, failure to meet clinically acceptable levels of computational cost, challenges associated with automating patient-specific model generation (i.e. robust image segmentation and mesh generation) and the complexity of applying biomechanical modelling methods in routine clinical practice.

  18. Evidence for biomechanics and motor learning research improving golf performance.

    Science.gov (United States)

    Keogh, Justin W L; Hume, Patria A

    2012-06-01

    The aim of this review was to determine how the findings of biomechanics and motor control/learning research may be used to improve golf performance. To be eligible, the biomechanics and motor learning studies had to use direct (ball displacement and shot accuracy) or indirect (clubhead velocity and clubface angle) golf performance outcome measures. Biomechanical studies suggested that reducing the radius path of the hands during the downswing, increasing wrist torque and/or range of motion, delaying wrist motion to late in the downswing, increasing downswing amplitude, improving sequential acceleration of body parts, improving weight transfer, and utilising X-factor stretch and physical conditioning programmes can improve clubhead velocity. Motor learning studies suggested that golf performance improved more when golfers focused on swing outcome or clubhead movement rather than specific body movements. A distributed practice approach involving multiple sessions per week of blocked, errorless practice may be best for improving putting accuracy of novice golfers, although variable practice may be better for skilled golfers. Video, verbal, or a combination of video and verbal feedback can increase mid-short iron distance in novice to mid-handicap (hcp) golfers. Coaches should not only continue to critique swing technique but also consider how the focus, structure, and types of feedback for practice may alter learning for different groups of golfers. PMID:22900408

  19. Biomechanical Remodeling of the Diabetic Gastrointestinal Tract

    DEFF Research Database (Denmark)

    Zhao, Jingbo; Liao, Donghua; Yang, Jian;

    2010-01-01

    several years, several studies demonstrated that experimental diabetes induces GI morphological and biomechanical remodeling. Following the development of diabetes, the GI wall becomes thicker and the stiffness of the GI wall increases in a time-dependent manner. It is well known that mechanosensitive...... the biomechanical environment of the mechanosensitive nerve endings, therefore, the structure as well as the tension, stress and strain distribution in the GI wall is important for the sensory and motor function. Biomechanical remodeling of diabetic GI tract including alterations of residual strain and increase...

  20. Biomechanical performance of new cardiovascular needles.

    Science.gov (United States)

    Thacker, J G; Ferguson, R E; Rodeheaver, G T; Edlich, R F

    2001-01-01

    Cardiovascular needles are now being manufactured from new stainless steel alloys containing high concentrations of nickel, Surgalloy and Ethalloy. The purpose of this study was to compare the biomechanical performance of a cardiovascular needle made of Surgalloy with a comparably sized needle made of Ethalloy. The parameters of biomechanical performance included sharpness, maintenance of sharpness, resistance to bending, and ductility. Because the biomechanical performance of these needles was remarkably similar, cardiovascular needles made of either the Surgalloy or Ethalloy alloys are recommended for cardiovascular surgery. PMID:11495105

  1. Tibiofemoral cartilage contact biomechanics in patients after reconstruction of a ruptured anterior cruciate ligament.

    Science.gov (United States)

    Hosseini, Ali; Van de Velde, Samuel; Gill, Thomas J; Li, Guoan

    2012-11-01

    We investigated the in vivo cartilage contact biomechanics of the tibiofemoral joint in patients after reconstruction of a ruptured anterior cruciate ligament (ACL). A dual fluoroscopic and MR imaging technique was used to investigate the cartilage contact biomechanics of the tibiofemoral joint during in vivo weight-bearing flexion of the knee in eight patients 6 months following clinically successful reconstruction of an acute isolated ACL rupture. The location of tibiofemoral cartilage contact, size of the contact area, cartilage thickness at the contact area, and magnitude of the cartilage contact deformation of the ACL-reconstructed knees were compared with those previously measured in intact (contralateral) knees and ACL-deficient knees of the same subjects. Contact biomechanics of the tibiofemoral cartilage after ACL reconstruction were similar to those measured in intact knees. However, at lower flexion, the abnormal posterior and lateral shift of cartilage contact location to smaller regions of thinner tibial cartilage that has been described in ACL-deficient knees persisted in ACL-reconstructed knees, resulting in an increase of the magnitude of cartilage contact deformation at those flexion angles. Reconstruction of the ACL restored some of the in vivo cartilage contact biomechanics of the tibiofemoral joint to normal. Clinically, recovering anterior knee stability might be insufficient to prevent post-operative cartilage degeneration due to lack of restoration of in vivo cartilage contact biomechanics. PMID:22528687

  2. Biomechanical Implications of Corrective Surgery for FAI: An Evidence-based Review.

    Science.gov (United States)

    Sampson, Joshua D; Safran, Marc R

    2015-12-01

    Femoroacetabular impingement (FAI) has been identified as a potential cause of hip osteoarthritis. The goal of FAI surgery is to relieve pain, and hopefully delay or prevent osteoarthritis of the hip. Several studies have now demonstrated favorable clinical outcomes after arthroscopic and open surgical correction of symptomatic FAI. The concept is restoration of normal hip anatomy may result in improved biomechanical function and kinematics of the hip, which may prevent or delay the progression of osteoarthritis. Although many clinical studies demonstrate restoration of "normal" anatomy, there are few studies evaluating improvement of biomechanics and function. To date, only 5 studies have been published in the English literature that study biomechanics and/or kinematics of the hip both preoperatively and postoperatively. At this point in the understanding of FAI, critical analysis of the literature suggests that FAI surgery can improve several parameters of biomechanical hip function. However, the impact of these improved biomechanics on the natural history and progression of degenerative changes in patients that are treated for symptomatic FAI has not been demonstrated. PMID:26524550

  3. Visualisation to enhance biomechanical tuning of ankle-foot orthoses (AFOs) in stroke: study protocol for a randomised controlled trial

    OpenAIRE

    Carse Bruce; Bowers Roy J; Meadows Barry C; Rowe Philip J

    2011-01-01

    Abstract Background There are a number of gaps in the evidence base for the use of ankle-foot orthoses for stroke patients. Three dimensional motion analysis offers an ideal method for objectively obtaining biomechanical gait data from stroke patients, however there are a number of major barriers to its use in routine clinical practice. One significant problem is the way in which the biomechanical data generated by these systems is presented. Through the careful design of bespoke biomechanica...

  4. Biomechanics of the press-fit phenomenon in dental implantology: an image-based finite element analysis

    OpenAIRE

    Frisardi Gianni; Barone Sandro; Razionale Armando V; Paoli Alessandro; Frisardi Flavio; Tullio Antonio; Lumbau Aurea; Chessa Giacomo

    2012-01-01

    Abstract Background A fundamental pre-requisite for the clinical success in dental implant surgery is the fast and stable implant osseointegration. The press-fit phenomenon occurring at implant insertion induces biomechanical effects in the bone tissues, which ensure implant primary stability. In the field of dental surgery, the understanding of the key factors governing the osseointegration process still remains of utmost importance. A thorough analysis of the biomechanics of dental implanto...

  5. Speckle photography in biomechanical testing

    Science.gov (United States)

    Kasprzak, Henryk T.; Podbielska, Halina

    1994-02-01

    The application of speckle photography in biomechanical testing of bones and surgical fixing devices is presented. Double-exposure speckle photography is used for measuring the in-plane deformation of broken lower leg bones supported with different fixing devices under axial loading. An osteosynthesis plate, an external fixator, and an intramedullar nail mounted on the tibia shaft are tested. The results for different loading conditions are analyzed and compared with those obtained by holographic interferometry. Further, the human hyoid bone is investigated by this method. The load is applied to the anterior surface of the body of the bone. All tested specimen show an asymmetric displacement, the greatest in a plane vertical to the load. An evaluation of fracture behavior can be done from the displacement pattern.

  6. Patient-specific models of cardiac biomechanics

    Science.gov (United States)

    Krishnamurthy, Adarsh; Villongco, Christopher T.; Chuang, Joyce; Frank, Lawrence R.; Nigam, Vishal; Belezzuoli, Ernest; Stark, Paul; Krummen, David E.; Narayan, Sanjiv; Omens, Jeffrey H.; McCulloch, Andrew D.; Kerckhoffs, Roy C. P.

    2013-07-01

    Patient-specific models of cardiac function have the potential to improve diagnosis and management of heart disease by integrating medical images with heterogeneous clinical measurements subject to constraints imposed by physical first principles and prior experimental knowledge. We describe new methods for creating three-dimensional patient-specific models of ventricular biomechanics in the failing heart. Three-dimensional bi-ventricular geometry is segmented from cardiac CT images at end-diastole from patients with heart failure. Human myofiber and sheet architecture is modeled using eigenvectors computed from diffusion tensor MR images from an isolated, fixed human organ-donor heart and transformed to the patient-specific geometric model using large deformation diffeomorphic mapping. Semi-automated methods were developed for optimizing the passive material properties while simultaneously computing the unloaded reference geometry of the ventricles for stress analysis. Material properties of active cardiac muscle contraction were optimized to match ventricular pressures measured by cardiac catheterization, and parameters of a lumped-parameter closed-loop model of the circulation were estimated with a circulatory adaptation algorithm making use of information derived from echocardiography. These components were then integrated to create a multi-scale model of the patient-specific heart. These methods were tested in five heart failure patients from the San Diego Veteran's Affairs Medical Center who gave informed consent. The simulation results showed good agreement with measured echocardiographic and global functional parameters such as ejection fraction and peak cavity pressures.

  7. Radiobiology in clinical radiation therapy - Part II: Current practice and new horizons

    International Nuclear Information System (INIS)

    Objective: This course is designed for residents in radiation oncology, preparing for their boards. The principles described in Part I are used to explain current practices in radiation oncology and as a basis for new initiatives. The multifraction regimens used in conventional radiotherapy were developed empirically, but can be understood in terms of radiobiological principles. Dividing the dose into many fractions reduces biological effectiveness due to repair of sublethal damage; this occurs in both tumors and normal tissues. Fractionation allows re-oxygenation to occur in tumors and so increases the effectiveness of a given total dose. Fractionation also leads to sensitization by reassortment of cycling tumor cells into radiosensitive phases of the cycle. Laboratory research also provides a rationale for modifications of existing fractionation protocols. The dose response relationship for late responding tissues is more 'curved' than for acute or early effects. Consequently the use of multiple fractions allows a greater separation of early and late effects in normal tissues. This has led to the introduction of hyperfractionation and accelerated treatment. Both involve two treatments per day (BID) but based on quite different rationales. The limitation of protraction is cell proliferation in the tumor, which may be accelerated as the tumor shrinks. Measurements of cell kinetics can identify fast growing tumors that may benefit from accelerated treatment. Hypoxia was early identified as a cause of resistance to cell killing by x-rays. This led to the development of electron affinic compounds as radiosensitizers of hypoxic cells. The new trend is the development of bioreductive drugs that are specifically cytotoxic to hypoxic cells i.e. hypoxic cytotoxins, but which still need to be combined with radiation. Fast neutrons were initially introduced, too, in an attempt to overcome the perceived problems of hypoxia, but clinical trials now are based on the premise

  8. Musculoskeletal Biomechanics in Cross-country Skiing

    OpenAIRE

    Holmberg, L. Joakim

    2012-01-01

    Why copy the best athletes? When you finally learn their technique, they may have already moved on. Using muscluloskeletal biomechanics you might be able to add the "know-why" so that you can lead, instead of being left in the swells. This dissertation presents the theoretical framework of musculoskeletal modeling using inverse dynamics with static optimization. It explores some of the possibilities and limitations of musculoskeletal biomechanics in cross-country skiing, especially double-pol...

  9. Tributes to Yuan-Cheng Fung on his 90th birthday biomechanics : from molecules to man

    CERN Document Server

    Chien, Shu; Schmid-Schönbein, Geert W

    2009-01-01

    This book is a tribute to Professor Yuan-Cheng Fung, the Father of Biomechanics and a pioneer in Bioengineering, in honor of his 90th Birthday. The book consists of articles contributed by his colleagues, students, friends and family. These articles illustrate Professor Fung's profound influence on outstanding leaders in bioengineering, especially biomechanics, and on the life and work of all people who have been in contact with him. The scientific topics covered range from fundamentals of science and engineering (e.g., residual stress, flow dynamics, and cellular signaling) to clinical disor

  10. Efeito da heparina sódica e da enoxaparina na consolidação de fratura da tíbia no rato: avaliação clínica e anatomopatológica e biomecânica Effect of heparin-sodium and enoxaparin on rats tibial fracture healing: clinical,anatomopathological, and biomechanical approach

    Directory of Open Access Journals (Sweden)

    Emilio Carlos Curcelli

    2005-01-01

    Full Text Available Foi realizado estudo experimental em ratos para avaliar o efeito do anticoagulante na consolidação óssea, conforme critérios clínicos, anatomopatológicos e biomecânicos. Manualmente, após perfuração do osso, foi produzida fratura aberta, na diáfise da tíbia direita, mantida sem imobilização, em 72 ratos machos da linhagem Wistar, com 60 dias de idade e peso médio de 242 gramas. Doze horas após a fratura, foi iniciado tratamento anticoagulante, mantido por 28 dias. Via subcutânea, um grupo recebeu heparina sódica na dose de 200UI/Kg de 12 em 12 horas, enquanto outro, recebeu enoxaparina na dose de 1mg/Kg de 12 em 12 horas, doses preconizadas para tratamento do tromboembolismo em humanos. O terceiro grupo, controle, recebeu água destilada. Durante o experimento, os animais foram avaliados clinicamente e após 28 dias, sacrificados. Nos animais dos três grupos, a evolução clínica foi semelhante. Mediante análise anatomopatológica efetuada por estudo descritivo e quantitativo, foi observada presença de fibrose, cartilagem e osso igualmente nos três grupos, sempre com predomínio de tecido ósseo. O estudo biomecânico, realizado por intermédio de ensaios de flexão, demonstrou coeficiente de rigidez e carga máxima semelhantes nos três grupos. Nenhuma diferença clínica, anatomopatológica e biomecânica foi encontrada, resultando todas as fraturas em consolidação de acordo com os critérios adotados, concluindo-se, portanto, que a heparina sódica e a enoxaparina nas doses, via e tempo de administração utilizados não interfiriram na consolidação da fratura da tíbia do rato.An experimental study in rats was accomplished to evaluate the effect of anticoagulant on fracture union, according to clinical, anatomopathological, and biomechanical approaches. Manually, after bone perforation, fracture was produced in the diaphysis of the right tibia, and maintained without immobilization in 72 male rats of Wistar lineage

  11. Impaired physical function, loss of muscle mass and assessment of biomechanical properties in critical ill patients

    DEFF Research Database (Denmark)

    Poulsen, Jesper Brøndum

    2012-01-01

    Intensive care unit (ICU) admission is associated with muscle weakness and ICU survivors report sustained limitation of physical capacity for years after discharge. Limited information is available on the underlying biomechanical properties responsible for this muscle function impairment. A...... potential to counteract loss of muscle mass. Despite the obvious clinical significance of muscle atrophy for the functional impairment observed in ICU survivors, no preventive therapies have been identified as yet. The overall aim of the present dissertation is to characterize aspects of physical function...... and biomechanical properties in ICU patients and to provide new insights into ICU-induced muscle wasting and the underlying biomechanical mechanisms responsible for the residual impairment of physical function in ICU survivors....

  12. Pilot biomechanical design of biomaterials for artificial nucleus prosthesis using 3D finite-element modeling

    Institute of Scientific and Technical Information of China (English)

    Qijin Huang; Guoquan Liu; Yong Li; Jin Gao; Zhengqiu Gu; Yuanzheng Ma; Haibin Xue

    2004-01-01

    Pilot biomechanical design of biomaterials for artificial nucleus prosthesis was carried out based on the 3D finite-element method. Two 3D models of lumbar intervertebral disc respectively with a real human nucleus and with the nucleus removed were developed and validated using published experimental and clinical data. Then the models with a stainless steel nucleus prosthesis implanted and with polymer nucleus prostheses of various properties implanted were used for the 3D finite-element biomechanical analysis. All the above simulation and analysis were carried out for the L4/L5 disc under a human worst-daily compression load of 2000 N. The results show that the polymer materials with Young's modulus of elasticity E = 0.1-100 MPa and Poisson's ratio v=0.35-0.5 are suitable to produce artificial nucleus prosthesis in view of biomechanical consideration.

  13. Justification for conducting neurological clinical trials as part of patient care within private practice.

    Science.gov (United States)

    Beran, R G; Stepanova, D; Beran, M E

    2016-05-01

    The aim of this review was to assess the benefits and drawbacks of conducting neurological clinical trials and research in private practice for the patients, clinician, Practice Manager, sponsors/Clinical Research Organisations (CROs) and Clinical Trial Coordinator (CTC) to determine if this is justified for all involved. A combination of literature reviews, original research articles and books were selected from 2005 to 2015. Provided that the practice has sufficient number of active trials to prevent financial loss, support staff, adequate facilities and equipment and time, the benefits outweigh the drawbacks. Clinical trials provide patients with more thorough monitoring, re-imbursement of trial-related expenses and the opportunity to try an innovative treatment at no charge when other options have failed. For the clinician, clinical trials provide more information to ensure better care for their patients and improved treatment methods, technical experience and global recognition. Trials collect detailed and up-to-date information on the benefits and risks of drugs, improving society's confidence in clinical research and pharmaceuticals, allow trial sponsors to explore new scientific questions and accelerate innovation. For the CTC, industry-sponsored clinical trials allow potential entry for a career in clinical research giving CTCs the opportunity to become Clinical Research Associates (CRAs), Study Start-Up Managers or Drug Safety Associates. PMID:27040457

  14. CHRONIC URTICARIAL IN CHILDHOOD. CLINICAL FEATURES OF CHRONIC URTICARIA IN CHILDREN. DIFFERENTIAL DIAGNOSTICS (PART II

    Directory of Open Access Journals (Sweden)

    N. A. Sinelnikova

    2014-07-01

    Full Text Available Abstract. Clinical structure of urticaria has been changed over last decade, due to discovery of an autoimmune form of the disease. This clinical form of chronic idiopathic urticaria comprises 30 to 52% of total. Incidence of physical urticaria varies from 17 to 20%, whereas other forms, including allergic urticaria, are diagnosed for < 5% of the patients. Different types of chronic urticaria exhibit their typical immunological features and clinical characteristics. A joint study of European Expert Group for Allergology, Clinical Immunology and Dermatology (EAACI/GA2LEN/EDF/UNEV is going on. Appropriate recommendations are aimed for improvement of diagnosis and management of children with this disease.

  15. The new production theory for health care through clinical reengineering: a study of clinical guidelines--Part I.

    Science.gov (United States)

    Sharp, J R

    1994-12-01

    Drucker writes that the emerging theory of manufacturing includes four principles and practices: statistical quality control, manufacturing accounting, modular organization, and systems approach. SQC is a rigorous, scientific method of identifying variation in the quality and productivity of a given production process, with an emphasis on improvement. The new manufacturing economics intends to integrate the production strategy with the business strategy in order to account for the biggest portions of costs that the old methods did not assess: time and automation. Production operations that are both standardized and flexible will allow the organization to keep up with changes in design, technology, and the market. The return on innovation in this environment is predicated on a modular arrangement of flexible steps in the process. Finally, the systems approach sees the entire process as being integrated in converting goods or services into economic satisfaction. There is now a major restructuring of the U.S. health care industry, and the incorporation of these four theories into health care reform would appear to be essential. This two-part article will address two problems: Will Drucker's theories relate to health care (Part I)? Will the "new manufacturing" in health care (practice guidelines) demonstrate cost, quality, and access changes that reform demands (Part II)? PMID:10139368

  16. Biomechanical Properties of Bone and Biomechanics of Age - Related Fractures - Review

    Directory of Open Access Journals (Sweden)

    Rezzan Günaydın

    2007-06-01

    Full Text Available From a biomechanical viewpoint, fractures are due to a structural failure of the bone. This failure occurs when the forces applied to the bone exceed its load – bearing capacity. The load – bearing capacity of a bone depends on the geometry (its size, shape and distribution of bone mass, and the material properties of a bone as well as the direction and magnitude of applied load. Bone fragility can be defined by biomechanical parameters such as strength, brittleness and work to failure. Strategies to reduce fracture risk must be based on a sound understanding of the cellular, molecular and biomechanical mechanisms that underlie the increased risk of fractures while aging. In this review biomechanics of bone and the etiology of age – related fractures from a biomechanical viewpoint have been discussed in the view of current literature. (From the World of Osteoporosis 2007;13:44-8

  17. The effect of a preoperative erythropoietin protocol as part of a multifaceted blood management program in daily clinical practice (CME)

    NARCIS (Netherlands)

    Doodeman, Hieronymus J.; van Haelst, Ingrid M. M.; Egberts, Toine C. G.; Bennis, Martin; Traast, Han S.; van Solinge, Wouter W.; Kalkman, Cor J.; van Klei, Wilton A.

    2013-01-01

    Background: The effectiveness of a preoperative erythropoietin (EPO) protocol to reduce allogeneic blood transfusions (ABTs) in daily clinical practice has been insufficiently studied. This study evaluated the effect of such a protocol, as part of a multifaceted blood management program, in patients

  18. Recent New Drug Approvals, Part 2: Drugs Undergoing Active Clinical Studies in Children

    OpenAIRE

    Chhim, Rebecca F.; Shelton, Chasity M.; Christensen, Michael L.

    2013-01-01

    The objective of this 2-part review is to provide information about drugs that have been recently approved by the US Food and Drug Administration. Part 1 reviewed recently approved drugs with pediatric indications. Part 2 reviews drugs recently approved only in adults and have published or ongoing studies in children.

  19. [Hoarseness: biomechanisms and quantitative laryngoscopy].

    Science.gov (United States)

    Eysholdt, U

    2014-07-01

    Every phonosurgical procedure alters endolaryngeal anatomy; be it by removing tissue, or injection or implantation of autologous or foreign material. However, the effect that an altered airflow cross section and changed soft tissue elasticity will have on the voice cannot be predicted. With the aim of promoting rational indications for phonosurgery, the current article explains the biomechanisms of the normal and the disordered voice, including the complex interdependence of tissue viscoelasticity, glottal airstream and sound production. According to European Laryngological Society (ELS) recommendations, five - not entirely mutually independent - evaluation criteria form the basis of indication assessments: self-rating (by the patient), proxy rating (by the physician), technical signal analysis (computerized), aerodynamics (spirometry) and vibration analysis (stroboscopy). The ELS evaluation standards agreed upon in 2001 enable indications and - by virtue of pre- and postoperative comparisons - therapeutic successes to be assessed. The 10-year-old ELS protocol has been updated by a real-time method for visualizing vocal fold vibrations: the phonovibrogram (PVG) has replaced stroboscopy. Independently of the morphological anatomic details of the larynx, PVG visualizes the symmetry and regularity of vocal fold motion, thus allowing preoperative estimation of tissue elasticity. PMID:25056650

  20. Radiation-induced bystander effect: The important part of ionizing radiation response. Potential clinical implications

    Directory of Open Access Journals (Sweden)

    Maria Wideł

    2009-08-01

    Full Text Available It has long been a central radiobiological dogma that the damaging effects of ionizing radiation, such as cell death, cytogenetic changes, apoptosis, mutagenesis, and carcinogenesis, are the results of the direct ionization of cell structures, particularly DNA, or indirect damage via water radiolysis products. However, several years ago attention turned to a third mechanism of radiation, termed the “bystander effect” or “radiation-induced bystander effect” (RIBE. This is induced by agents and signals emitted by directly irradiated cells and manifests as a lowering of survival, cytogenetic damage, apoptosis enhancement, and biochemical changes in neighboring non-irradiated cells. The bystander effect is mainly observed in in vitro experiments using very low doses of alpha particles (range; mGy, cGy, but also after conventional irradiation (X-rays, gamma rays at low as well as conventional doses. The mechanisms responsible for the bystander effect are complex and still poorly understood. It is believed that molecular signals released from irradiated cells induce different signaling ways in non-irradiated neighboring cells, leading to the observed events. The molecular signals may be transmitted through gap junction intercellular communication and through a medium transfer mechanism. The nature of these transmitted factors are diverse, and still not defi nitely established. It seems that RIBE may have important clinical implications for health risk associated with radiation exposure. Potentially, this effectmay have important implications in the creation of whole-body or localized side effects in tissues beyond the irradiation fi eld and also in low-dose radiological and radioisotope diagnostics. Factors emitted by irradiated cells may result in the risk of genetic instability, mutations, and second primary cancer induction. They might also have their own part in inducing and extending post-radiation side effects in normal tissue. The

  1. A Biomechanical Approach to Assessing Hip Fracture Risk

    Science.gov (United States)

    Ellman, Rachel

    2009-01-01

    Bone loss in microgravity is well documented, but it is difficult to quantify how declines in bone mineral density (BMD) contribute to an astronaut's overall risk of fracture upon return. This study uses a biomechanical approach to assessing hip fracture risk, or Factor of Risk (Phi), which is defined as the ratio of applied load to bone strength. All long-duration NASA astronauts from Expeditions 1-18 were included in this study (n=25), while crewmembers who flew twice (n=2) were treated as separate subjects. Bone strength was estimated based on an empirical relationship between areal BMD at the hip, as measured by DXA, and failure load, as determined by mechanical testing of cadaver femora. Fall load during a sideways fall was calculated from a previously developed biomechanical model, which takes into account body weight, height, gender, and soft tissue thickness overlying the lateral aspect of the hip that serves to attenuate the impact force. While no statistical analyses have been performed yet, preliminary results show that males in this population have a higher FOR than females, with a post- flight Phi of 0.87 and 0.36, respectively. FOR increases 5.1% from preflight to postflight, while only one subject crossed the fracture "threshold" of Phi = 1, for a total of 2 subjects with a postflight Phi > 1. These results suggest that men may be at greater risk for hip fracture due largely in part to their relatively thin soft tissue padding as compared to women, since soft tissue thickness has the highest correlation (R(exp 2)= .53) with FOR of all subject-specific parameters. Future work will investigate changes in FOR during recovery to see if baseline risk levels are restored upon return to 1-g activity. While dual x-ray absorptiometry (DXA) is the most commonly used clinical measure of bone health, it fails to provide compartment-specific information that is useful in assessing changes to bone quality as a result of microgravity exposure. Peripheral

  2. Role of Aquaporin 0 in lens biomechanics

    International Nuclear Information System (INIS)

    Maintenance of proper biomechanics of the eye lens is important for its structural integrity and for the process of accommodation to focus near and far objects. Several studies have shown that specialized cytoskeletal systems such as the beaded filament (BF) and spectrin-actin networks contribute to mammalian lens biomechanics; mutations or deletion in these proteins alters lens biomechanics. Aquaporin 0 (AQP0), which constitutes ∼45% of the total membrane proteins of lens fiber cells, has been shown to function as a water channel and a structural cell-to-cell adhesion (CTCA) protein. Our recent ex vivo study on AQP0 knockout (AQP0 KO) mouse lenses showed the CTCA function of AQP0 could be crucial for establishing the refractive index gradient. However, biomechanical studies on the role of AQP0 are lacking. The present investigation used wild type (WT), AQP5 KO (AQP5−/−), AQP0 KO (heterozygous KO: AQP0+/−; homozygous KO: AQP0−/−; all in C57BL/6J) and WT-FVB/N mouse lenses to learn more about the role of fiber cell AQPs in lens biomechanics. Electron microscopic images exhibited decreases in lens fiber cell compaction and increases in extracellular space due to deletion of even one allele of AQP0. Biomechanical assay revealed that loss of one or both alleles of AQP0 caused a significant reduction in the compressive load-bearing capacity of the lenses compared to WT lenses. Conversely, loss of AQP5 did not alter the lens load-bearing ability. Compressive load-bearing at the suture area of AQP0+/− lenses showed easy separation while WT lens suture remained intact. These data from KO mouse lenses in conjunction with previous studies on lens-specific BF proteins (CP49 and filensin) suggest that AQP0 and BF proteins could act co-operatively in establishing normal lens biomechanics. We hypothesize that AQP0, with its prolific expression at the fiber cell membrane, could provide anchorage for cytoskeletal structures like BFs and together they help to confer

  3. Extracorporeal membrane oxygenation - An anesthesiologist′s perspective - Part II: Clinical and technical consideration

    Directory of Open Access Journals (Sweden)

    Sandeep Chauhan

    2012-01-01

    Full Text Available Although the concept of extracorporeal membrane oxygenation (ECMO has remained unchanged, component technology has evolved considerably over the past three decades. Presently the clinical conditions requiring ECMO support have been updated with input from the outcome data of patient registries. Modern circuit configuration has become less cumbersome, safer, and more efficient. Technological advances now allow prolonged support with fewer complications compared to the past eras and facilitate transition to a single bedside caregiver model, similar to hemofiltration or ventricular-assist devices. The clinical considerations and indicators for placing the patient on ECMO, the various circuit configurations, clinical and technical issues, and management aspects are considered in this article.

  4. SPORT AND EXERCISE BIOMECHANICS (BIOS INSTANT NOTES

    Directory of Open Access Journals (Sweden)

    Paul Grimshaw

    2007-06-01

    Full Text Available DESCRIPTION Instant Notes on Sport and Exercise Biomechanics provides a broad overview of the fundamental concepts in exercise and sport biomechanics. PURPOSE The book aims to provide instant notes on essential information about biomechanics, and is designed to help undergraduate students to grasp the corresponding subjects in physical effort rapidly and easily. AUDIENCE The book provides a useful resource for undergraduate and graduate students as a fundamental reference book. For the researcher and lecturer it would be a starting point to plan and prepare more detailed experimental designs or lecture and/or laboratory classes in the field of exercise and sport biomechanics. It would also be interest to anyone who wonders the concepts like momentum possessed, whole body angular momentum, opposite parallel forces, superman position, parabolic flight path, joint/normal reaction force, etc. FEATURES This textbook is divided into following sections from A to F: kinematics of motion, kinetics of linear motion, kinetics of angular motion, special topics, applications and measurement techniques, respectively. In sub-sections the kinematics of motion are reviewed in detail, outlining the physics of motion. Furthermore, the discussions of mechanical characteristics of motion, the mechanisms of injury, and the analysis of the sport technique provide a source of valuable information for both students and lecturers in appropriate fields. ASSESSMENT This book is an important reading for biomechanics students, teachers and even researchers as well as anyone interested in understanding motion.

  5. Clinical education - place and part for becoming a practically trained radiographer

    International Nuclear Information System (INIS)

    Full text: The aim is to present the crucial role of clinical education for becoming a practically trained radiographer. It's been put on review and analysis the role of the clinic practice and pre-graduate practice into the education of the future specialist. It's presenting in detail every component of the program for study and the contribution of every module in it - image diagnostic, nuclear medicine and radiotherapy. the clinical education lasts six semesters in real working environment. The gradual increase of working hours creates conditions for higher educational quality. Students gradually master techniques, acquire skills and precision at working in an X-ray department, nuclear medicine units and radiotherapy, master communication techniques and acquire teamwork skills. the clinical education provides professional training, quick adaptation to realization and facilitates starting a job

  6. European clinical guidelines for Tourette syndrome and other tic disorders. Part I: assessment

    DEFF Research Database (Denmark)

    Cath, Danielle C; Hedderly, Tammy; Ludolph, Andrea G;

    2011-01-01

    members. Detailed clinical assessment guidelines of tic disorders and their comorbidities in both children and adults are presented. Screening methods that might be helpful and necessary for specialists' differential diagnosis process are suggested in order to further analyse cognitive abilities...

  7. Clinical Peculiarities of Recurrent and Chronic Bronchitis in Children (Part 1)

    OpenAIRE

    Makian, M. V.; Harhaun, V. A.; Maidannyk, V. H.

    2015-01-01

    Subjective manifestations in children with recurrent and chronic bronchitis were the subject of the research.The objective of the research was to evaluate the main clinical manifestations of recurrent and chronic bronchitis, analyze risk factors and preconditions for their occurence in children.Materials and methods of research. The comprehensive clinical and anamnestic examination of 120 children with bronchopulmonary pathology at the age of 3 to 18 (average age was 10.5±1.1 years) was condu...

  8. Database and Registry Research in Orthopaedic Surgery: Part 2: Clinical Registry Data.

    Science.gov (United States)

    Pugely, Andrew J; Martin, Christopher T; Harwood, Jared; Ong, Kevin L; Bozic, Kevin J; Callaghan, John J

    2015-11-01

    The use of large-scale national databases for observational research in orthopaedic surgery has grown substantially in the last decade, and the data sets can be categorized as either administrative claims or clinical registries. Clinical registries contain secondary data on patients with a specific diagnosis or procedure. The data are typically used for patient outcome surveillance to improve patient safety and health-care quality. Registries used in orthopaedic research exist at the regional, national, and international levels, and many were designed to specifically collect outcomes relevant to orthopaedics, such as short-term surgical complications, longer-term outcomes (implant survival or reoperations), and patient-reported outcomes. Although heterogeneous, clinical registries-in contrast to claims data-typically have a more robust list of variables, with relatively precise prospective data input, management infrastructure, and reporting systems. Some weaknesses of clinical registries include a smaller number of patients, inconstant follow-up duration, and use of sampling methods that may limit generalizability. Within the U.S., national joint registry adoption has lagged international joint registries. Given the changing health-care environment, it is likely that clinical registries will provide valuable information that has the potential to influence clinical practice improvement and health-care policy in the future. PMID:26537168

  9. Biomechanical analysis of lumbosacral fixation.

    Science.gov (United States)

    McCord, D H; Cunningham, B W; Shono, Y; Myers, J J; McAfee, P C

    1992-08-01

    Flexion testing was performed until failure on 66 lumbosacral bovine spinal segments comparing ten different lumbosacral instrumentation techniques. Maximum flexion moment at failure, flexural stiffness, and maximum angulation of the lumbosacral joint at failure were determined as well as strain measurements across the anterior aspect of the lumbosacral intervertebral disc using an extensometer. The maximum moment at failure was significantly greater for the only two devices that extended fixation into the ilium anterior to the projected image of the middle osteoligamentous column: ISOLA Galveston and ISOLA iliac screws (F = 12.2, P less than 0.001). The maximum stiffness at failure reinforced these findings (F = 23.7, P less than 0.001). A second subset of stability showed the advantages of S2 pedicle fixation by increasing the flexural lever arm (Cotrel-Dubousset butterfly plate, and Cotrel-Dubousset Chopin block, P less than 0.05). This exhaustive in vitro biomechanical study introduces the concept of a pivot point at the lumbosacral joint at the intersection of the middle osteoligamentous column (sagittal plane) and the lumbosacral intervertebral disc (transverse plane). A spinal surgeon can increase the stability of lumbosacral instrumentation by extending fixation through the anterior sacral cortex (Steffee plate group with pedicle screws that medially converge in a triangular fashion). A means of enhancing this fixation was to achieve more inferior purchase by extending the fixation down to the S2 pedicle (Cotrel-Dubousset Chopin and Cotrel-Dubousset butterfly groups). However, the best fixation was achieved by obtaining purchase between the iliac cortices down into the superior acetabular bone.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1523506

  10. 4th International Plant Biomechanics Conference Proceedings (Abstracts)

    Energy Technology Data Exchange (ETDEWEB)

    Frank W. Telewski; Lothar H. Koehler; Frank W. Ewers

    2003-07-20

    The 4th International Plant Biomechanics Conference facilitated an interdisciplinary exchange between scientists, engineers, and educators addressing the major questions encountered in the field of Plant Biomechanics. Subjects covered by the conference include: Evolution; Ecology; Mechanoreception; Cell Walls; Genetic Modification; Applied Biomechanics of Whole Plants, Plant Products, Fibers & Composites; Fluid Dynamics; Wood & Trees; Fracture Mechanics; Xylem Pressure & Water Transport; Modeling; and Introducing Plant Biomechanics in Secondary School Education.

  11. Biomechanics of the anterior cruciate ligament: Physiology, rupture and reconstruction techniques

    OpenAIRE

    Domnick, Christoph; Raschke, Michael J.; Herbort, Mirco

    2016-01-01

    The influences and mechanisms of the physiology, rupture and reconstruction of the anterior cruciate ligament (ACL) on kinematics and clinical outcomes have been investigated in many biomechanical and clinical studies over the last several decades. The knee is a complex joint with shifting contact points, pressures and axes that are affected when a ligament is injured. The ACL, as one of the intra-articular ligaments, has a strong influence on the resulting kinematics. Often, other meniscal o...

  12. Alveolar soft-part sarcoma: a rare soft-tissue malignancy with distinctive clinical and radiological features

    International Nuclear Information System (INIS)

    Alveolar soft-part sarcoma (ASPS) is a rare tumour. Certain distinctive clinical and radiological features suggest the correct diagnosis. There is moderate predilection for young women. ASPS almost always arises in skeletal muscle and occurs most frequently in the lower limbs. There is often a long clinical history and a large mass at presentation. Two young females with ASPS presented with very vascular tumours in the thigh, with prominent intra- and extra-tumoural blood vessels. The imaging findings and the existing literature are reviewed. (orig.)

  13. Multiscale modeling in biomechanics and mechanobiology

    CERN Document Server

    Hwang, Wonmuk; Kuhl, Ellen

    2015-01-01

    Presenting a state-of-the-art overview of theoretical and computational models that link characteristic biomechanical phenomena, this book provides guidelines and examples for creating multiscale models in representative systems and organisms. It develops the reader's understanding of and intuition for multiscale phenomena in biomechanics and mechanobiology, and introduces a mathematical framework and computational techniques paramount to creating predictive multiscale models.   Biomechanics involves the study of the interactions of physical forces with biological systems at all scales – including molecular, cellular, tissue and organ scales. The emerging field of mechanobiology focuses on the way that cells produce and respond to mechanical forces – bridging the science of mechanics with the disciplines of genetics and molecular biology. Linking disparate spatial and temporal scales using computational techniques is emerging as a key concept in investigating some of the complex problems underlying these...

  14. Sixth Computational Biomechanics for Medicine Workshop

    CERN Document Server

    Nielsen, Poul MF; Miller, Karol; Computational Biomechanics for Medicine : Deformation and Flow

    2012-01-01

    One of the greatest challenges for mechanical engineers is to extend the success of computational mechanics to fields outside traditional engineering, in particular to biology, biomedical sciences, and medicine. This book is an opportunity for computational biomechanics specialists to present and exchange opinions on the opportunities of applying their techniques to computer-integrated medicine. Computational Biomechanics for Medicine: Deformation and Flow collects the papers from the Sixth Computational Biomechanics for Medicine Workshop held in Toronto in conjunction with the Medical Image Computing and Computer Assisted Intervention conference. The topics covered include: medical image analysis, image-guided surgery, surgical simulation, surgical intervention planning, disease prognosis and diagnostics, injury mechanism analysis, implant and prostheses design, and medical robotics.

  15. Therapeutic songwriting in music therapy, Part II: Comparing the literature with practice across diverse clinical populations

    DEFF Research Database (Denmark)

    Baker, Felicity; Wigram, Tony; Stott, Dave;

    2009-01-01

    . Responses to a 21-question on-line survey were obtained from 419 professional music therapists practicing in 29 countries which focused on approaches to songwriting within their practice with a single clinical population. Results suggest that in general, the literature provides good representation for what...... is occurring in clinical practice. Generally, songs were composed with individual clients in single sessions, with lyrics created prior to the music. Clinicians had a significant role in creating the music with improvised and pre-determined musical structures being equally employed.  Chi-square or...... comparable  Exact tests (Fisher-Freeman-Halton) were applied to the data and significant associations were found according to clinical populations particularly with respect the number of sessions required to complete a song, approaches to composing lyrics and music, the context with which songwriting was...

  16. Role of Aquaporin 0 in lens biomechanics.

    Science.gov (United States)

    Sindhu Kumari, S; Gupta, Neha; Shiels, Alan; FitzGerald, Paul G; Menon, Anil G; Mathias, Richard T; Varadaraj, Kulandaiappan

    2015-07-10

    Maintenance of proper biomechanics of the eye lens is important for its structural integrity and for the process of accommodation to focus near and far objects. Several studies have shown that specialized cytoskeletal systems such as the beaded filament (BF) and spectrin-actin networks contribute to mammalian lens biomechanics; mutations or deletion in these proteins alters lens biomechanics. Aquaporin 0 (AQP0), which constitutes ∼45% of the total membrane proteins of lens fiber cells, has been shown to function as a water channel and a structural cell-to-cell adhesion (CTCA) protein. Our recent ex vivo study on AQP0 knockout (AQP0 KO) mouse lenses showed the CTCA function of AQP0 could be crucial for establishing the refractive index gradient. However, biomechanical studies on the role of AQP0 are lacking. The present investigation used wild type (WT), AQP5 KO (AQP5(-/-)), AQP0 KO (heterozygous KO: AQP0(+/-); homozygous KO: AQP0(-/-); all in C57BL/6J) and WT-FVB/N mouse lenses to learn more about the role of fiber cell AQPs in lens biomechanics. Electron microscopic images exhibited decreases in lens fiber cell compaction and increases in extracellular space due to deletion of even one allele of AQP0. Biomechanical assay revealed that loss of one or both alleles of AQP0 caused a significant reduction in the compressive load-bearing capacity of the lenses compared to WT lenses. Conversely, loss of AQP5 did not alter the lens load-bearing ability. Compressive load-bearing at the suture area of AQP0(+/-) lenses showed easy separation while WT lens suture remained intact. These data from KO mouse lenses in conjunction with previous studies on lens-specific BF proteins (CP49 and filensin) suggest that AQP0 and BF proteins could act co-operatively in establishing normal lens biomechanics. We hypothesize that AQP0, with its prolific expression at the fiber cell membrane, could provide anchorage for cytoskeletal structures like BFs and together they help to confer

  17. Analysis of Biomechanical Factors in Bend Running

    Directory of Open Access Journals (Sweden)

    Bing Zhang

    2013-03-01

    Full Text Available Sprint running is the demonstration of comprehensive abilities of technology and tactics, under various conditions. However, whether it is just to allocate the tracks for short-distance athletes from different racetracks has been the hot topic. This study analyzes its forces, differences in different tracks and winding influences, in the aspects of sport biomechanics. The results indicate, many disadvantages exist in inner tracks, middle tracks are the best and outer ones are inferior to middle ones. Thus it provides references for training of short-distance items in biomechanics and psychology, etc.

  18. Science Review: Vasopressin and the cardiovascular system part 2 – clinical physiology

    OpenAIRE

    Holmes, Cheryl L; Landry, Donald W.; Granton, John T.

    2003-01-01

    Vasopressin is emerging as a rational therapy for vasodilatory shock states. In part 1 of the review we discussed the structure and function of the various vasopressin receptors. In part 2 we discuss vascular smooth muscle contraction pathways with an emphasis on the effects of vasopressin on ATP-sensitive K+ channels, nitric oxide pathways, and interaction with adrenergic agents. We explore the complex and contradictory studies of vasopressin on cardiac inotropy and coronary vascular tone. F...

  19. Periodic Fever: A Review on Clinical, Management and Guideline for Iranian Patients - Part II

    OpenAIRE

    Ahmadinejad, Zahra; Mansouri, Sedigeh; Ziaee, Vahid; Aghighi, Yahya; Moradinejad, Mohammad-Hassan; Fereshteh-Mehregan, Fatemeh

    2014-01-01

    Periodic fever syndromes are a group of diseases characterized by episodes of fever with healthy intervals between febrile episodes. In the first part of this paper, we presented a guideline for approaching patients with periodic fever and reviewed two common disorders with periodic fever in Iranian patients including familial Mediterranean fever (FMF) and periodic fever syndromes except for periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA). In this part, we revi...

  20. Review article: A primer for clinical researchers in the emergency department: Part III: How to write a scientific paper.

    Science.gov (United States)

    Davidson, Andrew; McD Taylor, David; Babl, Franz E

    2012-08-01

    In this series we address key topics for clinicians who conduct research as part of their work in the ED. Analysis of research data does not represent the completion of a project as the findings need to be communicated to clinicians and other researchers in the field. In this section, we describe how to write up clinical research data for publication in a peer-reviewed journal. We also describe the editorial and peer-review process. PMID:22862751

  1. Stem cells in the heart: What’s the buzz all about? Part 2: Arrhythmic risks and clinical studies

    OpenAIRE

    Smith, Rachel Ruckdeschel; Barile, Lucio; Messina, Elisa; Marbán, Eduardo

    2008-01-01

    New approaches for cardiac repair have been enabled by the discovery that the heart contains its own reservoir of stem cells. In Part 1 of this review, we discussed various cardiac stem cell populations, reviewed our own work on cardiosphere-derived cells from human hearts, and outlined large animal preclinical models testing the regenerative potential of cardiac stem cells. Here we continue with a discussion on other adult stem cell sources with clinical potential. We summarize the critical ...

  2. Results of therapy of cancer of the movable part of the tongue with clinically intact regional lymph nodes

    International Nuclear Information System (INIS)

    A study was made of the frequency of metastatic spreading to the regional neck lymph nodes and long-term results of therapy of patients with cancer of the movable part of the tongue with clinically intact regional lymph nodes of the neck. The 5-year survival rates were 79, 50, 49 and 67% and 61% for the whole group. The main cause of death in 40% of the patients was a primary tumor recurrences

  3. Observations from Ground Zero at the World Trade Center in New York City, Part II: Theoretical and clinical considerations.

    Science.gov (United States)

    Acosta, Judith K; Levenson, Richard L

    2002-01-01

    Part I of this series discussed our observations of Ground Zero of the World Trade Center (WTC) immediately after the attack on September 11, 2001, as well as the stress-response of police officers on site. This paper offers a variety of clinical techniques for emergency mental health practitioners and first responders for use with victims of critical incidents. The suggested interventions are based on the theory and clinical practice of Emergency Medical Hypnosis, Neuro-Linguistic Programming, and Ericksonian Psychotherapy. Specific examples of how they were applied with police personnel following the World Trade Center attack are provided along with specific clinical guidelines. These interventions are designed to augment and enhance standard CISM, mental health, and medical practice in the field. PMID:12166017

  4. Clinical approaches to low back pain. Part 1. Epidemiology, diagnosis, and prevention.

    OpenAIRE

    R. W. Teasell; White, K.

    1994-01-01

    The epidemiology and difficulties in diagnosing low back pain are discussed. Clinical investigations should be limited to those tests that will provide useful information for effective management. Prevention is the best strategy for avoiding low back pain but is realistically hard to practise because the disorder has many environmental and intrinsic risk factors.

  5. LECTURES ON ACUPUNCTURE:PartClinical Acupuncture Lecture Twenty-two EPILEPSY

    Institute of Scientific and Technical Information of China (English)

    何海菊; 尚秀英; 刘文红

    2001-01-01

    Epilepsy is a kind of paroxysmal mental disorder and is characterized by sudden and repeated attack, and short duration. When it attacks, the patient falls unconscious suddenly with tic of the limbs or crying; after waking up, his or her condition is the same as normal person. In clinic it is generally divided into primary and secondary types, and each of them has manypatterns.

  6. Evidence-Based Practice for Children with Speech Sound Disorders: Part 2 Application to Clinical Practice

    Science.gov (United States)

    Baker, Elise; McLeod, Sharynne

    2011-01-01

    Purpose: This article provides both a tutorial and a clinical example of how speech-language pathologists (SLPs) can conduct evidence-based practice (EBP) when working with children with speech sound disorders (SSDs). It is a companion paper to the narrative review of 134 intervention studies for children who have an SSD (Baker & McLeod, 2011).…

  7. LECTURES ON ACUPUNCTURE:PartClinical Acupuncture Lecture Twenty-Three HYSTERIA

    Institute of Scientific and Technical Information of China (English)

    潘兴芳; 何海菊

    2001-01-01

    Hysteria usually refers to a neuropsychosis caused by excessive mental stimulation or adverse suggestion. In majority of the patients, it breaks out suddenly, manifested as transient amentia or sensory and kinetic disturbance but without organic pathologic change. The clinical symptoms may occur or disappear or are changed under suggestion. This disease is often seen in young people especially in women.

  8. Bacteriemia during endodontic treatment in relation to the technique of biomechanical preparation: randomized clinical trial Bacteriemia durante o tratamento endodôntico em função da técnica de preparo biomecânico: ensaio clínico randomizado

    Directory of Open Access Journals (Sweden)

    Adriane Tenório Dourado

    2005-12-01

    Full Text Available OBJECTIVE: The aim of this randomized clinical trial was to evaluate the frequency of bacteriemia during endodontic treatment, with comparison between two techniques for biomechanical preparation of the root canal system. MATERIALS AND METHODS: The sample comprised 50 patients aged 16 to 52 years, of both genders, which were divided into 2 groups with 25 patients each. Group I underwent biomechanical preparation by the step-back technique, and Group II was treated by the rotary technique with nickel-titanium instruments (K3. Patients were submitted to antisepsis of the oral cavity with chlorhexidine digluconate and three samples of blood were collected for blood culture: preoperatively, immediately after the biomechanical preparation and 10 minutes later. The significance level adopted was 5.0%, and analysis was performed by descriptive and inferential statistics by means of the Fisher's exact test, Fisher-Freeman-Halton test and Student's t test. Data were analyzed on the Statexact and SPSS softwares. RESULTS: All blood cultures achieved before and immediately after preparation were negative. On the other hand, with regard to the blood cultures collected 10 minutes after preparation, one (4% positive case was found for Group I. However, this difference was not statistically significant (p = 0.50. CONCLUSION: The frequency of bacteriemia was low and observed just for Group I.OBJETIVO: O objetivo deste ensaio clínico randomizado foi avaliar a freqüência de bacteriemia durante o tratamento endodôntico comparando duas técnicas de preparo biomecânico do sistema de canais radiculares. MATERIAIS E MÉTODOS: A amostra constou de 50 pacientes, com idade variando entre 16 e 52 anos e de ambos os sexos, sendo dividida em 2 grupos de 25 pacientes. No Grupo I, realizou-se o preparo biomecânico através da técnica escalonada com recuo progressivo programado, e, no Grupo II, por meio técnica rotatória, empregando instrumentos de níquel-titânio (K3

  9. Biomechanical Analysis of Force Distribution in Human Finger Extensor Mechanisms

    Directory of Open Access Journals (Sweden)

    Dan Hu

    2014-01-01

    Full Text Available The complexities of the function and structure of human fingers have long been recognised. The in vivo forces in the human finger tendon network during different activities are critical information for clinical diagnosis, surgical treatment, prosthetic finger design, and biomimetic hand development. In this study, we propose a novel method for in vivo force estimation for the finger tendon network by combining a three-dimensional motion analysis technique and a novel biomechanical tendon network model. The extensor mechanism of a human index finger is represented by an interconnected tendinous network moving around the phalanx’s dorsum. A novel analytical approach based on the “Principle of Minimum Total Potential Energy” is used to calculate the forces and deformations throughout the tendon network of the extensor mechanism when subjected to an external load and with the finger posture defined by measurement data. The predicted deformations and forces in the tendon network are in broad agreement with the results obtained by previous experimental in vitro studies. The proposed methodology provides a promising tool for investigating the biomechanical function of complex interconnected tendon networks in vivo.

  10. Quality and Safety in Health Care, Part XII: The Work System, Testing, and Clinical Reasoning.

    Science.gov (United States)

    Harolds, Jay A

    2016-07-01

    Donabedian felt the 3 major components affecting quality were process, structure, and outcome. Later investigators often substitute the word "structure" for a broader concept called the "work system." One component of the latter is the people involved, and for diagnosis, this often is best done with a diagnostic team. The work system in diagnosis has many obstacles to achieve optimum performance. There are also important problems with how tests are ordered and interpreted and clinical reasoning and biases. PMID:26975018

  11. Extracorporeal membrane oxygenation - An anesthesiologist′s perspective - Part II: Clinical and technical consideration

    OpenAIRE

    Sandeep Chauhan; S Subin

    2012-01-01

    Although the concept of extracorporeal membrane oxygenation (ECMO) has remained unchanged, component technology has evolved considerably over the past three decades. Presently the clinical conditions requiring ECMO support have been updated with input from the outcome data of patient registries. Modern circuit configuration has become less cumbersome, safer, and more efficient. Technological advances now allow prolonged support with fewer complications compared to the past eras and facilitate...

  12. Interdisciplinary Vertical Integration: The Future of Biomechanics

    Science.gov (United States)

    Gregor, Robert J.

    2008-01-01

    The field of biomechanics has grown rapidly in the past 30 years in both size and complexity. As a result, the term might mean different things to different people. This article addresses the issues facing the field in the form of challenges biomechanists face in the future. Because the field is so diverse, strength within the different areas of…

  13. Expose Mechanical Engineering Students to Biomechanics Topics

    Science.gov (United States)

    Shen, Hui

    2011-01-01

    To adapt the focus of engineering education to emerging new industries and technologies nationwide and in the local area, a biomechanics module has been developed and incorporated into a mechanical engineering technical elective course to expose mechanical engineering students at ONU (Ohio Northern University) to the biomedical engineering topics.…

  14. Biomechanics/risk management (Working Group 2)

    DEFF Research Database (Denmark)

    Sanz, Mariano; Naert, Ignace; Gotfredsen, Klaus

    2009-01-01

    INTRODUCTION: The remit of this workgroup was to update the existing knowledge base in biomechanical factors, navigation systems and medications that may affect the outcome of implant therapy. MATERIAL AND METHODS: The literature was systematically searched and critically reviewed. Five manuscrip...

  15. The biomechanical interaction between horse and rider

    NARCIS (Netherlands)

    Cocq, de P.

    2012-01-01

    The forces exerted by a rider on a horse have a direct influence on the mechanical load experienced by the horse and consequently on its motion pattern. The aim of this thesis is to explore the biomechanical interaction between rider, saddle and horse in order to get insight in the loading of the ho

  16. The Value of Biomechanical Research in Dance.

    Science.gov (United States)

    Ranney, D. A.

    Simple observation of dance movement, while very useful, can lead to misconceptions, about the physical realities of dance movement, that make learning difficult. This gap between reality and understanding can be reduced by the application of biomechanical techniques such as cinematography, electromyography, and force-plate analysis. Biomechanical…

  17. Are cranial biomechanical simulation data linked to known diets in extant taxa? A method for applying diet-biomechanics linkage models to infer feeding capability of extinct species.

    Directory of Open Access Journals (Sweden)

    Zhijie Jack Tseng

    Full Text Available Performance of the masticatory system directly influences feeding and survival, so adaptive hypotheses often are proposed to explain craniodental evolution via functional morphology changes. However, the prevalence of "many-to-one" association of cranial forms and functions in vertebrates suggests a complex interplay of ecological and evolutionary histories, resulting in redundant morphology-diet linkages. Here we examine the link between cranial biomechanical properties for taxa with different dietary preferences in crown clade Carnivora, the most diverse clade of carnivorous mammals. We test whether hypercarnivores and generalists can be distinguished based on cranial mechanical simulation models, and how such diet-biomechanics linkages relate to morphology. Comparative finite element and geometric morphometrics analyses document that predicted bite force is positively allometric relative to skull strain energy; this is achieved in part by increased stiffness in larger skull models and shape changes that resist deformation and displacement. Size-standardized strain energy levels do not reflect feeding preferences; instead, caniform models have higher strain energy than feliform models. This caniform-feliform split is reinforced by a sensitivity analysis using published models for six additional taxa. Nevertheless, combined bite force-strain energy curves distinguish hypercarnivorous versus generalist feeders. These findings indicate that the link between cranial biomechanical properties and carnivoran feeding preference can be clearly defined and characterized, despite phylogenetic and allometric effects. Application of this diet-biomechanics linkage model to an analysis of an extinct stem carnivoramorphan and an outgroup creodont species provides biomechanical evidence for the evolution of taxa into distinct hypercarnivorous and generalist feeding styles prior to the appearance of crown carnivoran clades with similar feeding preferences.

  18. Are cranial biomechanical simulation data linked to known diets in extant taxa? A method for applying diet-biomechanics linkage models to infer feeding capability of extinct species.

    Science.gov (United States)

    Tseng, Zhijie Jack; Flynn, John J

    2015-01-01

    Performance of the masticatory system directly influences feeding and survival, so adaptive hypotheses often are proposed to explain craniodental evolution via functional morphology changes. However, the prevalence of "many-to-one" association of cranial forms and functions in vertebrates suggests a complex interplay of ecological and evolutionary histories, resulting in redundant morphology-diet linkages. Here we examine the link between cranial biomechanical properties for taxa with different dietary preferences in crown clade Carnivora, the most diverse clade of carnivorous mammals. We test whether hypercarnivores and generalists can be distinguished based on cranial mechanical simulation models, and how such diet-biomechanics linkages relate to morphology. Comparative finite element and geometric morphometrics analyses document that predicted bite force is positively allometric relative to skull strain energy; this is achieved in part by increased stiffness in larger skull models and shape changes that resist deformation and displacement. Size-standardized strain energy levels do not reflect feeding preferences; instead, caniform models have higher strain energy than feliform models. This caniform-feliform split is reinforced by a sensitivity analysis using published models for six additional taxa. Nevertheless, combined bite force-strain energy curves distinguish hypercarnivorous versus generalist feeders. These findings indicate that the link between cranial biomechanical properties and carnivoran feeding preference can be clearly defined and characterized, despite phylogenetic and allometric effects. Application of this diet-biomechanics linkage model to an analysis of an extinct stem carnivoramorphan and an outgroup creodont species provides biomechanical evidence for the evolution of taxa into distinct hypercarnivorous and generalist feeding styles prior to the appearance of crown carnivoran clades with similar feeding preferences. PMID:25923776

  19. Measurement scales in clinical research of the upper extremity, part 2: outcome measures in studies of the hand/wrist and shoulder/elbow.

    Science.gov (United States)

    Badalamente, Marie; Coffelt, Laureen; Elfar, John; Gaston, Glenn; Hammert, Warren; Huang, Jerry; Lattanza, Lisa; Macdermid, Joy; Merrell, Greg; Netscher, David; Panthaki, Zubin; Rafijah, Greg; Trczinski, Douglas; Graham, Brent

    2013-02-01

    Part 1 of this article outlined the basic characteristics of useful clinical measurement instruments and described scales used to measure general health, pain, and patient satisfaction. Part 2 describes the features of some of the scales most commonly used in clinical research in the hand, wrist, elbow, and shoulder. PMID:23351913

  20. Developmental biomechanics of the human cervical spine.

    Science.gov (United States)

    Nuckley, David J; Linders, David R; Ching, Randal P

    2013-04-01

    Head and neck injuries, the leading cause of death for children in the U.S., are difficult to diagnose, treat, and prevent because of a critical void in our understanding of the biomechanical response of the immature cervical spine. The objective of this study was to investigate the functional and failure biomechanics of the cervical spine across multiple axes of loading throughout maturation. A correlational study design was used to examine the relationships governing spinal maturation and biomechanical flexibility curves and tolerance data using a cadaver human in vitro model. Eleven human cadaver cervical spines from across the developmental spectrum (2-28 years) were dissected into segments (C1-C2, C3-C5, and C6-C7) for biomechanical testing. Non-destructive flexibility tests were performed in tension, compression, flexion, extension, lateral bending, and axial rotation. After measuring their intact biomechanical responses, each segment group was failed in different modes to measure the tissue tolerance in tension (C1-C2), compression (C3-C5), and extension (C5-C6). Classical injury patterns were observed in all of the specimens tested. Both the functional (pmechanics exhibited significant relationships with age. Nonlinear flexibility curves described the functional response of the cervical spine throughout maturation and elucidated age, spinal level, and mode of loading specificity. These data support our understanding of the child cervical spine from a developmental perspective and facilitate the generation of injury prevention or management schema for the mitigation of child spine injuries and their deleterious effects. PMID:23415075

  1. On the prospect of patient-specific biomechanics without patient-specific properties of tissues.

    Science.gov (United States)

    Miller, Karol; Lu, Jia

    2013-11-01

    This paper presents main theses of two keynote lectures delivered at Euromech Colloquium "Advanced experimental approaches and inverse problems in tissue biomechanics" held in Saint Etienne in June 2012. We are witnessing an advent of patient-specific biomechanics that will bring in the future personalized treatments to sufferers all over the world. It is the current task of biomechanists to devise methods for clinically-relevant patient-specific modeling. One of the obstacles standing before the biomechanics community is the difficulty in obtaining patient-specific properties of tissues to be used in biomechanical models. We postulate that focusing on reformulating computational mechanics problems in such a way that the results are weakly sensitive to the variation in mechanical properties of simulated continua is more likely to bear fruit in near future. We consider two types of problems: (i) displacement-zero traction problems whose solutions in displacements are weakly sensitive to mechanical properties of the considered continuum; and (ii) problems that are approximately statically determinate and therefore their solutions in stresses are also weakly sensitive to mechanical properties of constituents. We demonstrate that the kinematically loaded biomechanical models of the first type are applicable in the field of image-guided surgery where the current, intraoperative configuration of a soft organ is of critical importance. We show that sac-like membranes, which are prototypes of many thin-walled biological organs, are approximately statically determinate and therefore useful solutions for wall stress can be obtained without the knowledge of the wall's properties. We demonstrate the clinical applicability and effectiveness of the proposed methods using examples from modeling neurosurgery and intracranial aneurysms. PMID:23491073

  2. Searching for Tourette’s syndrome gene. Part 1. Heterogeneity of clinical phenotypes

    Directory of Open Access Journals (Sweden)

    Anna Kowalska

    2012-02-01

    Full Text Available The French neuropsychiatrist Georges Gilles de la Tourette described in 1885 the “Maladie des Tics” which later was named after him, as Gilles de la Tourette syndrome (GTS. Gilles de la Tourette syndrome is a neurodevelopmental disorder characterized by simple and complex motor and vocal tics with multiple neuropsychiatric comorbidities. GTS is often concurrent with obsessive-compulsive disorder (OCD and attention deficit hyperactivity disorder (ADHD. There are several clinical GTS subtypes: GTS only, GTS OCD, and GTS OCD ADHD. Additional clinical aspects of the disorder include occurrence of anger episodes, anxiety and mood disorders, and learning and sleeping disturbances. The genetics of GTS is complex and remains unclear. So far, no causative candidate genes have been identified. However, segregation studies in families and twins with GTS provide strong evidence for the existence of a genetic background associated with a multifactorial mode of inheritance. Progress in studies on genome variability among patients with GTS is necessary to improve pharmacotherapeutic strategies of the disorder.

  3. ”No-preparation” and Minimally Invasive Veneers in Clinical Practice: Part 1

    Directory of Open Access Journals (Sweden)

    Beata Smielak

    2015-03-01

    Full Text Available Objectives: “No preparation” veneers and veneers requiring minimal preparation of dental enamel are steadily increasing in popularity among today’s dental practitioners but they are suitable for selected individual cases. Overview: The present study discusses the indications for, and limitations to, the use of ultra-thin veneers, their drawbacks and advantages. It also describes the veneer placement procedure, taking into account the issues of proper diagnostics and treatment planning. Clinical significance: “No preparation” veneers and veneers requiring minimal preparation should always be recommended whenever the clinical and laboratory conditions allow it. Their greatest advantage lies in the fact that they save healthy dental tissue and thus offer an excellent alternative to traditional veneers and crowns. On the other hand, “no-preparation” and minimally invasive veneers that are poorly designed and fabricated, heavy or chunky in appearance, and overcontoured can negatively influence the shape of a patient’s teeth and lead to periodontal problems.

  4. Plant-based medicines for anxiety disorders, part 2: a review of clinical studies with supporting preclinical evidence.

    Science.gov (United States)

    Sarris, Jerome; McIntyre, Erica; Camfield, David A

    2013-04-01

    Research in the area of herbal psychopharmacology has revealed a variety of promising medicines that may provide benefit in the treatment of general anxiety and specific anxiety disorders. However, a comprehensive review of plant-based anxiolytics has been absent to date. Thus, our aim was to provide a comprehensive narrative review of plant-based medicines that have clinical and/or preclinical evidence of anxiolytic activity. We present the article in two parts. In part one, we reviewed herbal medicines for which only preclinical investigations for anxiolytic activity have been performed. In this current article (part two), we review herbal medicines for which there have been both preclinical and clinical investigations of anxiolytic activity. A search of MEDLINE (PubMed), CINAHL, Scopus and the Cochrane Library databases was conducted (up to 28 October 2012) for English language papers using the search terms 'anxiety' OR 'anxiety disorder' OR 'generalized anxiety disorder' OR 'social phobia' OR 'post-traumatic stress disorder' OR 'panic disorder' OR 'agoraphobia' OR 'obsessive compulsive disorder' in combination with the search terms 'Herb*' OR 'Medicinal Plants' OR 'Botanical Medicine' OR 'Chinese herb*', in addition to individual herbal medicines. This search of the literature revealed 1,525 papers, of which 53 plants were included in the review (having at least one study using the whole plant extract). Of these plants, 21 had human clinical trial evidence (reviewed here in part two), with the other 32 having solely preclinical evidence (reviewed in part one). Support for efficacy was found for chronic use (i.e. greater than one day) of the following herbs in treating a range of anxiety disorders in human clinical trials: Piper methysticum, Matricaria recutita, Ginkgo biloba, Scutellaria lateriflora, Silybum marianum, Passiflora incarnata, Withania somniferum, Galphimia glauca, Centella asiatica, Rhodiola rosea, Echinacea spp., Melissa officinalis and Echium

  5. [Dynamics of hip joint biomechanics in patients with coxarthrosis at the time of hippotherapy].

    Science.gov (United States)

    Nareklishvili, T M

    2008-02-01

    The problems of degenerative-dystrophic abnormalities stimulate the development of new skills and methods of treatment and rehabilitation of the diseases. The goal of the study was to determine the efficacy of hippotherapy in patients with coxarthrosis, according to functional and biomechanical parameters. Hippotherapy involves the utilization of horseback riding to stimulate the patient's normal reactions and locomotion; to improve the balance and coordination of movement, normalize muscle tension, and eliminate pathological reflexes. The advantage of the hippotherapy is in the specific posture, which is adopted by hip joint at the time of riding and in movement, which is accomplished by rider, at different paces of the horse. 10 female patients from 14 to 32 years old with coxarthrosis were under the observation. The rehabilitation of the patients was carried out by means of hippotherapy, which consisted of three months riding three times a week. To evaluate the efficacy of treatment, a new method of biomechanical registration of hip joint movement during hippotherapy on pacing horse was developed. The dynamics of biomechanical curves before and after the treatment, as well as the clinical and functional parameters of the patients allowed the authors to conclude: hippotherapy improves a hip joint functional state in patients with coxarthrosis; improves the muscle-tendineous component of hip joint movement. Hippotherapy may be considered as the pathogenetic method of treatment of coxarthrosis. Drawing the biomechanical curve of hip joint movement at the time of riding is the objective method of studying its function. PMID:18401052

  6. Radiobiology in clinical radiation therapy part II: current practice and new horizons

    International Nuclear Information System (INIS)

    were initially introduced, too, in an attempt to overcome the perceived problems of hypoxia, but clinical trials now are based on the premise that neutron RBE values are larger for slowly proliferating tumors which is in closer accord with the clinical observation that neutrons offer a clear advantage over x-rays only in the case of a few tumor sites. Boron Neutron Arpture Therapy remains an attractive possibility if suitable compounds can be developed. An important new horizon is the development of predictive assays to individualize treatment, and to identify patients that might benefit from new treatment strategies. Three predictive assays have already reached the clinic and have been proven to have some usefulness in clinical trials. First, there is the attempt to identify patients who may be unusually sensitive or resistant to radiation by measuring the fraction of cells (from a tumor or normal tissue specimen) surviving a dose of 2 Gy. Second, there are several methods available to identify those tumors that contain a significant proportion of hypoxia cells. Third, estimates of the proliferative potential of a tumor are now possible from a single tumor biopsy (Tpot). The future of cancer therapy is likely to be revolutionized by developments in molecular biology. The radiosensitivity of cells is determined by repair genes and molecular checkpoint genes. The malignant process is governed by oncogenes and suppressor genes which may also influence response to radiation. A radiation exposure appears to 'turn on' early responding genes, many of which involve cytokines, i.e. growth factors that control movement through the cell cycle. Many of these genes are being identified and characterized. In addition, there is increasing evidence that some (and maybe most) common cancers do not occur at random in the population, but are a consequence of inherited susceptibility genes. In the near future it may be possible to identify alterations in these genes early in life which

  7. [Multidetector computed tomography of coronary arteries: state of the art. Second part: clinical applications].

    Science.gov (United States)

    González, Aloha Meave; Rosas, Erick Alexánderson; Valero, Mónica Rodríguez; Ramírez, Gabriela Meléndez; García, Alfonso Martínez; Fernández, Carlos Sierra; Torres, Rodrigo Calleja; Castillo, Leonardo García-Rojas; Molina, Pedro Alberto Lamothe; Zarza, Mary Carmen Herrera; de Avila, Martha Armas; López, Juan Manuel Ochoa; Vázquez-Lamadrid, Jorge; Hayama, Eric Kimura

    2008-01-01

    At the beginning of the evaluation of Coronary Artery Disease (CAD), Coronary Multidetector Computed Tomography (MDCT) was exclusively used to detect calcified plaques in coronary arteries through the Calcium Score, whose value by itself is limited. Nowadays, thanks to the technological advancements, potential clinical applications, with this method, include detection of coronary arterial stenosis, assessment of coronary bridges, and evaluation of anomalous coronaries. The intraluminal coronary stent evaluation is not possible yet, but this might become possible with the new-generation scanners. At the moment, the published results seem to be promising, nonetheless, the enthusiasm generated by this method should be accompanied by adequate training, as well as by its validation and certification. PMID:18754411

  8. The Mallory body: morphological, clinical and experimental studies (Part 1 of a literature survey)

    DEFF Research Database (Denmark)

    Jensen, K; Gluud, C

    1994-01-01

    , a variety of experimental drugs have been developed that cause Mallory body formation, but markedly different cell dynamics and metabolic pathways may raise questions about the relevance of such animal models for human Mallory body formation. In conclusion, the Mallory body is indicative but not......To aid understanding of markers of disease and predictors of outcome in alcohol-exposed systems, we undertook a literature survey of more than 700 articles to view the morphological characteristics and the clinical and experimental epidemiology of the Mallory body. Mallory bodies are filaments of...... electron microscopy (with fibrillar structure parallel, random or absent), they remain stereotypical manifestations of hepatocyte injury. A summary of the conditions associated with Mallory bodies in the literature and their validity and potential etiological relationships is presented and discussed...

  9. An Update on Hidradenitis Suppurativa (Part I): Epidemiology, Clinical Aspects, and Definition of Disease Severity.

    Science.gov (United States)

    Martorell, A; García-Martínez, F J; Jiménez-Gallo, D; Pascual, J C; Pereyra-Rodriguez, J; Salgado, L; Vilarrasa, E

    2015-11-01

    Hidradenitis suppurativa is a chronic inflammatory disorder that has attracted increasing attention in recent years due to underestimations of prevalence and the considerable impact of the condition on interpersonal relationships, physical appearance, self-esteem, and body image. Although hidradenitis suppurative has a significant psychological impact on patients and can even cause physical limitations when thick scarring results in limb mobility limitation, until very recently little evidence was available relating to its epidemiology, etiology, or pathogenesis. In this review, we highlight the latest advances in our understanding of the epidemiological and clinical aspects of hidradenitis suppurativa. We will also look at the different classification systems for hidradenitis suppurativa and discuss the emergence of skin ultrasound as a promising technique for monitoring the course of this chronic inflammatory disease. PMID:26254550

  10. LECTURE ON ACUPUNCTURE Part I Clinical Acupuncture Lecture Thirty- two ASTHMA

    Institute of Scientific and Technical Information of China (English)

    徐立; 尚秀葵; 董洪英

    2003-01-01

    @@ Asthma is an allergic disease, characterized by paroxysmal dyspnea with wheezing sound in the throat and inability to lie flat. It may attack in people with different ages and in different seasons, especially in cold and cool seasons or during sudden changes of the weather. TCM thinks that asthma is often caused by retention of phlegm and fluid in the lungs due to disturbance of activities of qi. In the early stage of this disease, it generally belongs to excess syndrome. If attacking repeatedly, it may bring disasters to different zangfu-organs including spleen, lung,kidney and heart. Clinically this disease may be divided into 5 types: retention of cold-fluid in the lungs, accumulation of phlegm-heat, deficiency of both lung-qi and spleen-qi, deficiency of both lung-yin and kidney-yin, and deficiency of both heart-yang and kidney-yang.

  11. European clinical guidelines for Tourette syndrome and other tic disorders. Part III: behavioural and psychosocial interventions

    DEFF Research Database (Denmark)

    Verdellen, Cara; van de Griendt, Jolande; Hartmann, Andreas;

    2011-01-01

    This clinical guideline provides recommendations for the behavioural and psychosocial interventions (BPI) of children and adolescents with tic disorders prepared by a working group of the European Society for the Study of Tourette Syndrome (ESSTS). A systematic literature search was conducted to...... obtain an update on the efficacy of BPI for tics. Relevant studies were identified using computerised searches of the Medline and PsycINFO databases and the Cochrane Library for the years 1950-2010. The search identified no meta-analyses, yet twelve (systematic) reviews and eight randomised controlled...... trials provided evidence for the current review. Most evidence was found for habit reversal training (HRT) and the available but smaller evidence also supports the efficacy of exposure with response prevention (ERP). Both interventions are considered first line behavioural treatments for tics for both...

  12. Management of radiation therapy-induced mucositis in head and neck cancer patients. Part I: Clinical significance, pathophysiology and prevention

    Directory of Open Access Journals (Sweden)

    Wei Cheong Ngeow

    2011-12-01

    Full Text Available Oropharyngeal mucositis is the acute inflammatory and ulcerative reaction of the oral mucosa following radiation therapy to the head and neck region. It is such a common problem that nearly all head and neck cancer patients develop some degree of mucositis. This complication is usually transient in nature but it also represents an important clinical problem as it is a painful, debilitating, dose-dependent side effect for which there is no widely acceptable prophylaxis or effective treatment. As several authoritative groups have recently either undertaken systematic reviews or issued guidelines on the management of mucositis, it is the aim of this review to provide instead an overview of all the possible remedies available, as well as highlighting to researchers the gaps that need to be filled. The first part of this review outlines the clinical significance and pathophysiology of radiation-induced mucositis, and looks into some of the preventive approaches available.

  13. Genetic and epigenetic features in radiation sensitivity. Part II: implications for clinical practice and radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Bourguignon, Michel H. [Direction Generale de la Surete Nucleaire et de la Radioprotection, Paris Cedex 12 (France); CEA-DSV-DRM Hopital, Service de Recherches en Hemato-Immunologie, Saint Louis, Paris (France); Gisone, Pablo A.; Perez, Maria R.; Michelin, Severino; Dubner, Diana; Giorgio, Marina di [Autoridad Regulatoria Nuclear, Laboratorio de Radiopatologia, Buenos Aires (Argentina); Carosella, Edgardo D. [CEA-DSV-DRM Hopital, Service de Recherches en Hemato-Immunologie, Saint Louis, Paris (France)

    2005-03-01

    Recent progress especially in the field of gene identification and expression has attracted greater attention to the genetic and epigenetic susceptibility to cancer, possibly enhanced by ionising radiation. This issue is especially important for radiation therapists since hypersensitive patients may suffer from adverse effects in normal tissues following standard radiation therapy, while normally sensitive patients could receive higher doses of radiation, offering a better likelihood of cure for malignant tumours. Although only a small percentage of individuals are ''hypersensitive'' to radiation effects, all medical specialists using ionising radiation should be aware of the aforementioned progress in medical knowledge. The present paper, the second of two parts, reviews human disorders known or strongly suspected to be associated with hypersensitivity to ionising radiation. The main tests capable of detecting such pathologies in advance are analysed, and ethical issues regarding genetic testing are considered. The implications for radiation protection of possible hypersensitivity to radiation in a part of the population are discussed, and some guidelines for nuclear medicine professionals are proposed. (orig.)

  14. Genetic and epigenetic features in radiation sensitivity. Part II: implications for clinical practice and radiation protection.

    Science.gov (United States)

    Bourguignon, Michel H; Gisone, Pablo A; Perez, Maria R; Michelin, Severino; Dubner, Diana; Giorgio, Marina Di; Carosella, Edgardo D

    2005-03-01

    Recent progress especially in the field of gene identification and expression has attracted greater attention to the genetic and epigenetic susceptibility to cancer, possibly enhanced by ionising radiation. This issue is especially important for radiation therapists since hypersensitive patients may suffer from adverse effects in normal tissues following standard radiation therapy, while normally sensitive patients could receive higher doses of radiation, offering a better likelihood of cure for malignant tumours. Although only a small percentage of individuals are "hypersensitive" to radiation effects, all medical specialists using ionising radiation should be aware of the aforementioned progress in medical knowledge. The present paper, the second of two parts, reviews human disorders known or strongly suspected to be associated with hypersensitivity to ionising radiation. The main tests capable of detecting such pathologies in advance are analysed, and ethical issues regarding genetic testing are considered. The implications for radiation protection of possible hypersensitivity to radiation in a part of the population are discussed, and some guidelines for nuclear medicine professionals are proposed. PMID:15692806

  15. Genetic and epigenetic features in radiation sensitivity. Part II: implications for clinical practice and radiation protection

    International Nuclear Information System (INIS)

    Recent progress especially in the field of gene identification and expression has attracted greater attention to the genetic and epigenetic susceptibility to cancer, possibly enhanced by ionising radiation. This issue is especially important for radiation therapists since hypersensitive patients may suffer from adverse effects in normal tissues following standard radiation therapy, while normally sensitive patients could receive higher doses of radiation, offering a better likelihood of cure for malignant tumours. Although only a small percentage of individuals are ''hypersensitive'' to radiation effects, all medical specialists using ionising radiation should be aware of the aforementioned progress in medical knowledge. The present paper, the second of two parts, reviews human disorders known or strongly suspected to be associated with hypersensitivity to ionising radiation. The main tests capable of detecting such pathologies in advance are analysed, and ethical issues regarding genetic testing are considered. The implications for radiation protection of possible hypersensitivity to radiation in a part of the population are discussed, and some guidelines for nuclear medicine professionals are proposed. (orig.)

  16. Role of Aquaporin 0 in lens biomechanics

    Energy Technology Data Exchange (ETDEWEB)

    Sindhu Kumari, S.; Gupta, Neha [Physiology and Biophysics, Stony Brook University, Stony Brook, NY (United States); Shiels, Alan [Washington University School of Medicine, St. Louis, MO (United States); FitzGerald, Paul G. [Cell Biology and Human Anatomy, School of Medicine, University of California, Davis, CA (United States); Menon, Anil G. [University of Cincinnati College of Medicine, Cincinnati, OH (United States); Mathias, Richard T. [Physiology and Biophysics, Stony Brook University, Stony Brook, NY (United States); SUNY Eye Institute, NY (United States); Varadaraj, Kulandaiappan, E-mail: kulandaiappan.varadaraj@stonybrook.edu [Physiology and Biophysics, Stony Brook University, Stony Brook, NY (United States); SUNY Eye Institute, NY (United States)

    2015-07-10

    Maintenance of proper biomechanics of the eye lens is important for its structural integrity and for the process of accommodation to focus near and far objects. Several studies have shown that specialized cytoskeletal systems such as the beaded filament (BF) and spectrin-actin networks contribute to mammalian lens biomechanics; mutations or deletion in these proteins alters lens biomechanics. Aquaporin 0 (AQP0), which constitutes ∼45% of the total membrane proteins of lens fiber cells, has been shown to function as a water channel and a structural cell-to-cell adhesion (CTCA) protein. Our recent ex vivo study on AQP0 knockout (AQP0 KO) mouse lenses showed the CTCA function of AQP0 could be crucial for establishing the refractive index gradient. However, biomechanical studies on the role of AQP0 are lacking. The present investigation used wild type (WT), AQP5 KO (AQP5{sup −/−}), AQP0 KO (heterozygous KO: AQP0{sup +/−}; homozygous KO: AQP0{sup −/−}; all in C57BL/6J) and WT-FVB/N mouse lenses to learn more about the role of fiber cell AQPs in lens biomechanics. Electron microscopic images exhibited decreases in lens fiber cell compaction and increases in extracellular space due to deletion of even one allele of AQP0. Biomechanical assay revealed that loss of one or both alleles of AQP0 caused a significant reduction in the compressive load-bearing capacity of the lenses compared to WT lenses. Conversely, loss of AQP5 did not alter the lens load-bearing ability. Compressive load-bearing at the suture area of AQP0{sup +/−} lenses showed easy separation while WT lens suture remained intact. These data from KO mouse lenses in conjunction with previous studies on lens-specific BF proteins (CP49 and filensin) suggest that AQP0 and BF proteins could act co-operatively in establishing normal lens biomechanics. We hypothesize that AQP0, with its prolific expression at the fiber cell membrane, could provide anchorage for cytoskeletal structures like BFs and

  17. Biomechanical failure of metacarpal fracture resorbable plate fixation.

    Science.gov (United States)

    Lionelli, Gerald T; Korentager, Richard A

    2002-08-01

    Metacarpal fractures are a relatively common hand injury that may require operative intervention to ensure adequate reduction and stabilization. The use of permanent hardware, although acceptable, may lead to complications and an increased number of surgical procedures. The use of resorbable hardware such as poly-L-lactic acid and polyglycolic acid copolymer plates and screws may circumvent some of these complications. In vitro studies have demonstrated that the biomechanical characteristics of these resorbable plates may provide the rigid fixation necessary to allow for union of metacarpal fractures in vivo. However, limited clinical data are available regarding the success of their use in this application. The authors present what they believe is the first reported case of the failure of a poly-L-lactic acid and polyglycolic acid copolymer miniplate after use in the fixation of a metacarpal shaft fracture. PMID:12187350

  18. Biomechanical Effect of Chinese Immobilization Using Little Splint

    Institute of Scientific and Technical Information of China (English)

    WANG Mei; ZHAO Namula

    2014-01-01

    Immobilization using little splint is an original innovation of Chinese people for the fracture fixation, which is simple to use and clinically effective. It was found that Chinese immobilization using little splint can make the non-invasive, uncovering, and trouble free healing of bone fracture via harmonious unity of the structure stability and the force balance, of the motion stability and the stress adaptability, of the constant and discontinuous physiological stress. The biomechanical effect of Chinese immobilization using little splint, including entirety, dynamic, and functional fixity, is the root cause of its inheritance and the use up to now, and also is a direction of today's fracture fixation towards personalization, individuality and entirety.

  19. Denture-Related Biomechanical Factors for Fixed Partial Dentures Retained on Short Dental Implants.

    Science.gov (United States)

    Pommer, Bernhard; Hingsammer, Lukas; Haas, Robert; Mailath-Pokorny, Georg; Busenlechner, Dieter; Watzek, Georg; Fürhauser, Rudolf

    2015-01-01

    Prosthodontically driven biomechanical considerations are essential for longterm successful outcomes in dental implant therapy. Correct protocols seek to preclude potential consequences associated with functional and parafunctional occlusal overload such as screw loosening, component fracture, compromised marginal bone maintenance, and the integrity of the induced osseointegration response. Other concerns also need to be addressed, more especially when other implants are selected, for example: bridge insertion torque (BIT) in cases of immediate loading, cantilever length-anteroposterior spread ratio (CL-AP), overall crown-to-implant ratio (oCIR), total bone-to-implant surface area (tBICA), and the status of the opposing dentition. In spite of promising clinical results, evidence-based clinical protocols demand that such biomechanical limits still need to be determined. PMID:26218027

  20. Periodic Fever: a review on clinical, management and guideline for Iranian patients - part I.

    Science.gov (United States)

    Ahmadinejad, Zahra; Mansori, Sedigeh; Ziaee, Vahid; Alijani, Neda; Aghighi, Yahya; Parvaneh, Nima; Mordinejad, Mohammad-Hassan

    2014-02-01

    Periodic fever syndromes are a group of diseases characterized by episodes of fever with healthy intervals between febrile episodes. The first manifestation of these disorders are present in childhood and adolescence, but infrequently it may be presented in young and middle ages. Genetic base has been known for all types of periodic fever syndromes except periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA). Common periodic fever disorders are Familial Mediterranean fever (FMF) and PFAPA. In each patient with periodic fever, acquired infection with chronic and periodic nature should be ruled out. It depends on epidemiology of infectious diseases. Some of them such as Familial Mediterranean fever and PFAPA are common in Iran. In Iran and other Middle East countries, brucellosis, malaria and infectious mononucleosis should be considered in differential diagnosis of periodic fever disorders especially with fever and arthritis manifestation. In children, urinary tract infection may be presented as periodic disorder, urine analysis and culture is necessary in each child with periodic symptoms. Some malignancies such as leukemia and tumoral lesions should be excluded in patients with periodic syndrome and weight loss in any age. After excluding infection, malignancy and cyclic neutropenia, FMF and PFAPA are the most common periodic fever disorders. Similar to other countries, Hyper IgD, Chronic Infantile Neurologic Cutaneous and Articular, TRAPS and other auto-inflammatory syndromes are rare causes of periodic fever in Iranian system registry. In part 1 of this paper we reviewed the prevalence of FMF and PFAPA in Iran. In part 2, some uncommon auto-inflammatory disorders such as TRAPS, Hyper IgD sydrome and cryopyrin associated periodic syndromes will be reviewed. PMID:25793039

  1. Clinical Scenarios in Chronic Kidney Disease: Parenchymal Chronic Renal Diseases - Part 2.

    Science.gov (United States)

    Petrucci, Ilaria; Samoni, Sara; Meola, Mario

    2016-01-01

    Secondary nephropathies can be associated with disreactive immunological disorders or with a non-inflammatory glomerular damage. In systemic lupus erythematosus (SLE), scleroderma and rheumatoid arthritis as in other connective tissue diseases, kidney volume and cortex echogenicity are the parameters that best correlate with clinical severity of the disease, even if the morphological aspect is generally non-specific. Doppler studies in SLE document the correlation between resistance indexes (RIs) values and renal function. Acquired immunodeficiency syndrome (HIV) causes different types of renal damage. At ultrasound (US), kidneys have almost a normal volume, while during superinfection they enlarge (coronal diameter >13 cm) and become globular, loosing their normal aspect. Cortex appears highly hyperechoic, uniform or patchy. Microcalcifications of renal cortex and medulla are a US sign that can suggest HIV. In amyloidosis, kidneys appear normal or increased in volume in the early stages of disease. Renal cortex is diffusely hyperechoic and pyramids can show normal size and morphology, but more often they appear poorly defined and hyperechoic. RIs are very high since the early stages of the disease. Nephromegaly with normal kidney shape is the first sign of lymphoma or multiple myeloma. In systemic vasculitis, renal cortex is diffusely hyperechoic, while pyramids appear hypoechoic and globular due to interstitial edema. When vasculitis determines advanced chronic kidney disease stages, kidneys show no specific signs. Microcirculation damage is highlighted by increased RIs values >0.70 in the chronic phase. PMID:27169551

  2. Clinical Implementation Of Megavoltage Cone Beam CT As Part Of An IGRT Program

    International Nuclear Information System (INIS)

    Knowing where the tumor is at all times during treatment is the next challenge in the field of radiation therapy. This issue has become more important because with treatments such as Intensity Modulated Radiation Therapy (IMRT), healthy tissue is spared by using very tight margins around the tumor. These tight margins leave very small room for patient setup errors. The use of an imaging modality in the treatment room as a way to localize the tumor for patient set up is generally known as ''Image Guided Radiation Therapy'' or IGRT. This article deals with a form of IGRT known as Megavoltage Cone Beam Computed Tomography (MCBCT) using a Siemens Oncor linear accelerator currently in use at Firelands Regional Medical Center. With MCBCT, we are capable of acquiring CT images right before the treatment of the patient and then use this information to position the patient tumor according to the treatment plan. This article presents the steps followed in order to clinically implement this system, as well as some of the quality assurance tests suggested by the manufacturer and some tests developed in house

  3. On the prospect of patient-specific biomechanics without patient-specific properties of tissues

    OpenAIRE

    Miller, Karol; Lu, Jia

    2013-01-01

    This paper presents main theses of two keynote lectures delivered at Euromech Colloquium “Advanced experimental approaches and inverse problems in tissue biomechanics” held in Saint Etienne in June 2012. We are witnessing an advent of patient-specific biomechanics that will bring in the future personalized treatments to sufferers all over the world. It is the current task of biomechanists to devise methods for clinically-relevant patient-specific modeling. One of the obstacles standing before...

  4. Análise clínica e biomecânica do efeito do diclofenaco sódico na consolidação da fratura da tíbia no rato Clinical and biomechanical analysis of the effect of diclofenac sodium in tibial fracture healing in rats

    Directory of Open Access Journals (Sweden)

    Sérgio Swain Müller

    2004-12-01

    Full Text Available Os AINH (Antiinflamatórios não hormonais são agentes utilizados na prática clínica que interferem no processo inflamatório pela inibição da síntese de prostaglandinas e tromboxanos. Alguns trabalhos experimentais investigaram sua ação no processo de consolidação de fraturas, por meio de estudos clínicos e histológicos, sendo escassas as análises biomecânicas. Nesse estudo foram utilizados 20 ratos da linhagem Wistar, divididos aleatoriamente em dois grupos iguais: grupo A (controle e grupo B (tratado com diclofenaco sódico. Em ambos os grupos foram realizadas fraturas abertas, após perfuração, na tíbia direita. A administração da droga foi via intramuscular, dose única diária, por 28 dias. Os animais foram pesados semanalmente. Após o sacrifício as tíbias foram dissecadas, pesadas e submetidas a ensaio biomecânico de flexão analisando-se carga máxima, deformação e coeficiente de rigidez. Observou-se que no grupo tratado com AINH não houve aumento do peso corpóreo a partir da segunda semana e as tíbias fraturadas foram mais pesadas. Neste grupo o calo ósseo suportou menor carga máxima, apresentando maior deformação e menor coeficiente de rigidez. Nos animais tratados, o osso não fraturado também se mostrou menos rígido. Concluiu-se, nas condições estudadas, que o DS alterou o processo de consolidação e o metabolismo ósseo, levando a retardo na maturação do calo e menor rigidez do osso intacto, respectivamente.The antinflammatories are agents utilized on clinical practice that interfere on inflammatory process by synthesis inhibition of prostaglandin and tromboxanes. Some experimental studies investigated their action on the fractures consolidation process, through clinical and histological studies, as the biomechanical analyses are scarce. In this study, 20 (twenty Wistar pedigree rats were used, aleatory divided into two groups: A group (control and B group (treated with diclofenac. In both

  5. Prevalence and effect of myths in clinical orthopaedics in Western part of Uttar Pradesh

    Directory of Open Access Journals (Sweden)

    Arun Vashisht

    2016-06-01

    Full Text Available Background: Myths in the field of medicine regarding the treatment of health problems are frequently observed, which may not only retard the recovery but often be harmful for the patients. We were baffled to see lot of patients under the influence of certain myths about treatment of their orthopaedic ailments. The aim of this observational, prospective study was to dispel the misconceptions and to create awareness in the society about the bad effects of these myths. Methods: 1285 patients aged 20-55 years, suffering from fractures, neck pain, backache, osteoarthritis knee, myofascial trigger points, episacroiliac lipomas etc. and being under the influence of one or the other myth about the treatment of their ailments, were included in this study. Results: All Patients were counseled and made to realize the harmful effects of their false beliefs regarding treatment of their orthopaedic ailments. Every patient was treated as necessitated for the ailment. All patients were found satisfied at the end of treatment, and were happy after dispelling their myths. Conclusions: Misconceptions do not have any scientific basis rather these are rooted in the society due to high rate of illiteracy and lack of health education. Being a part and parcel of the health care system, it becomes our duty to create awareness among patients about the harmful effects of the prevailing false beliefs by imparting proper health care advice and treatment to relieve the sufferings of our patients. [Int J Res Med Sci 2016; 4(6.000: 2197-2201

  6. Risk management in clinical practice. Part 5. Ethical considerations for dental enhancement procedures.

    Science.gov (United States)

    Ahmad, I

    2010-09-11

    After the demise of the Industrial Age, we currently live in an 'Information Age' fuelled mainly by the Internet, with an ever-increasing medically and dentally literate population. The media has played its role by reporting scientific advances, as well as securitising medical and dental practices. Reality television such as 'Extreme makeovers' has also raised public awareness of body enhancements, with a greater number of people seeking such procedures. To satiate this growing demand, the dental industry has flourished by introducing novel cosmetic products such as bleaching kits, tooth coloured filling materials and a variety of dental ceramics. In addition, one only has to browse through a dental journal to notice innumerable courses and lectures on techniques for providing cosmetic dentistry. The incessant public interest, combined with unrelenting marketing by companies is gradually shifting the balance of dental care from a healing to an enhancement profession. The purpose of this article is to endeavour to answer questions such as, What is aesthetic or cosmetic dentistry? Why do patients seek cosmetic dentistry? Are enhancement procedures a part of dental practice? What, if any, ethical guidelines and constraints apply to elective enhancement procedures? What is the role of the dentist in providing or encouraging this type of 'therapy'? What treatment modalities are available for aesthetic dental treatment? PMID:20829856

  7. Biomedical Imaging and Computational Modeling in Biomechanics

    CERN Document Server

    Iacoviello, Daniela

    2013-01-01

    This book collects the state-of-art and new trends in image analysis and biomechanics. It covers a wide field of scientific and cultural topics, ranging from remodeling of bone tissue under the mechanical stimulus up to optimizing the performance of sports equipment, through the patient-specific modeling in orthopedics, microtomography and its application in oral and implant research, computational modeling in the field of hip prostheses, image based model development and analysis of the human knee joint, kinematics of the hip joint, micro-scale analysis of compositional and mechanical properties of dentin, automated techniques for cervical cell image analysis, and iomedical imaging and computational modeling in cardiovascular disease.   The book will be of interest to researchers, Ph.D students, and graduate students with multidisciplinary interests related to image analysis and understanding, medical imaging, biomechanics, simulation and modeling, experimental analysis.

  8. Biomechanical study of percutaneous lumbar diskectomy

    International Nuclear Information System (INIS)

    Objective: To investigate the stiffness of lumbar spine after the injury caused by percutaneous diskectomy and evaluate the efficiency of percutaneous lumbar diskectomy by biomechanical study. Methods: Four fresh lumbar specimens were used to analyse load-displacement curves in the intact lumbar spine and vertical disc-injured lumbar spine. The concepts of average flexibility coefficient (f) and standardized average flexibility coefficient (fs) were also introduced. Results: The load-displacement curves showed a good stabilization effect of the intact lumbar spine and disc-injured lumbar spine in flexion, extension, right and left bending. The decrease of anti-rotation also can be detected (P<0.05). Conclusion: In biomechanical study, percutaneous lumbar diskectomy is one of the efficiency methods to treat lumbar diac hernia

  9. Biomechanics and anterior cruciate ligament reconstruction

    OpenAIRE

    Vercillo Fabio; Dede Ozgur; Wu Changfu; Woo Savio; Noorani Sabrina

    2006-01-01

    Abstract For years, bioengineers and orthopaedic surgeons have applied the principles of mechanics to gain valuable information about the complex function of the anterior cruciate ligament (ACL). The results of these investigations have provided scientific data for surgeons to improve methods of ACL reconstruction and postoperative rehabilitation. This review paper will present specific examples of how the field of biomechanics has impacted the evolution of ACL research. The anatomy and biome...

  10. Homogenization of biomechanical models for plant tissues

    OpenAIRE

    Piatnitski, Andrey; Ptashnyk, Mariya

    2015-01-01

    In this paper homogenization of a mathematical model for plant tissue biomechanics is presented. The microscopic model constitutes a strongly coupled system of reaction-diffusion-convection equations for chemical processes in plant cells, the equations of poroelasticity for elastic deformations of plant cell walls and middle lamella, and Stokes equations for fluid flow inside the cells. The chemical process in cells and the elastic properties of cell walls and middle lamella are coupled becau...

  11. BIOMECHANICAL ANALYSIS OF HUMAN FEMUR BONE

    OpenAIRE

    RAJI NARELIYA,; VEERENDRA KUMAR

    2011-01-01

    Biomechanics is the theory of how tissues, cells, muscles, bones, organs and the motion of them and how their form and function are regulated by basic mechanical properties. A finite element model of bones with accurate geometry and material properties retrieved from CT scan data are being widely used to make realistic investigations on the mechanical behavior of bone structures. The aim of this study is to create a model of real proximal human femur bone for evaluating the finite element ana...

  12. Numerical Simulation of Some Biomechanical Problems

    Czech Academy of Sciences Publication Activity Database

    Nedoma, Jiří; Klézl, Z.; Fousek, J.; Kestřánek, Zdeněk; Stehlík, J.

    2003-01-01

    Roč. 61, 3-6 (2003), s. 283-295. ISSN 0378-4754. [MODELLING 2001. IMACS Conference on Mathematical Modelling and Computational Methods in Mechanics, Physics, Biomechanics and Geodynamics /2./. Pilsen, 19.06.2001-25.06.2001] Institutional research plan: AV0Z1030915 Keywords : non-linear elasticity * contact problems * variational inequality * finite element method * wrist * spine * fracture Subject RIV: BA - General Mathematics Impact factor: 0.558, year: 2003

  13. SERVICE IN BADMINTON: A BIOMECHANICAL STUDY

    OpenAIRE

    Saleem Ahmed; Sartaj Khan; Manu Mishra; Touheed Akhter

    2015-01-01

    To find out the differences between forehand and backhand short services in badminton, the present study was designed to analyze the biomechanical variables and segmental angles - shuttle velocity, wrist angle, elbow angle and shoulder angle of six male badminton players. The data were recorded during “North-Zone Intervarsity Championship” held at Aligarh Muslim University, Aligarh, India. All subjects in the study were right handed badminton players. The mean age, body height ...

  14. Analysis of Biomechanical Factors in Bend Running

    OpenAIRE

    Bing Zhang; Xinping You; Feng Li

    2013-01-01

    Sprint running is the demonstration of comprehensive abilities of technology and tactics, under various conditions. However, whether it is just to allocate the tracks for short-distance athletes from different racetracks has been the hot topic. This study analyzes its forces, differences in different tracks and winding influences, in the aspects of sport biomechanics. The results indicate, many disadvantages exist in inner tracks, middle tracks are the best and outer ones are inferior to midd...

  15. The incidental pulmonary nodule in a child. Part 2: Commentary and suggestions for clinical management, risk communication and prevention

    Energy Technology Data Exchange (ETDEWEB)

    Westra, Sjirk J. [Massachusetts General Hospital, Division of Pediatric Radiology, Boston, MA (United States); Thacker, Paul G. [Medical University of South Carolina, Department of Radiology, Charleston, SC (United States); Podberesky, Daniel J. [Nemours Children' s Hospital, Department of Radiology, Orlando, FL (United States); Lee, Edward Y. [Boston Children' s Hospital, Department of Pediatric Radiology, Boston, MA (United States); Iyer, Ramesh S. [Seattle Children' s Hospital, Department of Radiology, Seattle, WA (United States); Hegde, Shilpa V. [Arkansas Children' s Hospital, Department of Radiology, Little Rock, AR (United States); Guillerman, R.P. [Texas Children' s Hospital, Department of Radiology, Houston, TX (United States); Mahani, Maryam Ghadimi [University of Michigan Health System, Section of Pediatric Radiology, C. S. Mott Children' s Hospital, Department of Radiology, Ann Arbor, MI (United States)

    2015-05-01

    The incidental detection of small lung nodules in children is a vexing consequence of an increased reliance on CT. We present an algorithm for the management of lung nodules detected on CT in children, based on the presence or absence of symptoms, the presence or absence of elements in the clinical history that might explain these nodules, and the imaging characteristics of the nodules (such as attenuation measurements within the nodule). We provide suggestions on how to perform a thoughtfully directed and focused search for clinically occult extrathoracic disease processes (including malignant disease) that may present as an incidentally detected lung nodule on CT. This algorithm emphasizes that because of the lack of definitive information on the natural history of small solid nodules that are truly detected incidentally, their clinical management is highly dependent on the caregivers' individual risk tolerance. In addition, we present strategies to reduce the prevalence of these incidental findings, by preventing unnecessary chest CT scans or inadvertent inclusion of portions of the lungs in scans of adjacent body parts. Application of these guidelines provides pediatric radiologists with an important opportunity to practice patient-centered and evidence-based medicine. (orig.)

  16. The incidental pulmonary nodule in a child. Part 2: Commentary and suggestions for clinical management, risk communication and prevention

    International Nuclear Information System (INIS)

    The incidental detection of small lung nodules in children is a vexing consequence of an increased reliance on CT. We present an algorithm for the management of lung nodules detected on CT in children, based on the presence or absence of symptoms, the presence or absence of elements in the clinical history that might explain these nodules, and the imaging characteristics of the nodules (such as attenuation measurements within the nodule). We provide suggestions on how to perform a thoughtfully directed and focused search for clinically occult extrathoracic disease processes (including malignant disease) that may present as an incidentally detected lung nodule on CT. This algorithm emphasizes that because of the lack of definitive information on the natural history of small solid nodules that are truly detected incidentally, their clinical management is highly dependent on the caregivers' individual risk tolerance. In addition, we present strategies to reduce the prevalence of these incidental findings, by preventing unnecessary chest CT scans or inadvertent inclusion of portions of the lungs in scans of adjacent body parts. Application of these guidelines provides pediatric radiologists with an important opportunity to practice patient-centered and evidence-based medicine. (orig.)

  17. Occupational biomechanics of athletes and dancers: a comparative approach.

    Science.gov (United States)

    Bejjani, F J

    1987-07-01

    Muscle strains represent more than a third of all injuries in both dancers and athletes. Although often overlooked, anatomic variations play an important role in the etiology of these injuries, as does strength imbalance between agonists and antagonists. The incidence of spondylolysis is unusually high in ballet dancers and certain athletic groups, such as gymnasts, javelin throwers, and weight-lifters. Mechanical factors play a major role and can be exacerbated by congenital abnormalities. Various permanent adaptive musculoskeletal changes have been described both in dancers and athletes, especially those that start at a very young age. Task-related adaptive changes can also be seen in isokinetic strength measurements of various muscle groups, such as the spine muscles of Flamenco dancers. Shoes and floor surfaces can be directly responsible in part or in whole for many sports and dance injuries. "Vibration-pressure" diagrams are suggested as an objective way to document their effect on biomechanical behavior. PMID:2886209

  18. Computational Biomechanics Theoretical Background and BiologicalBiomedical Problems

    CERN Document Server

    Tanaka, Masao; Nakamura, Masanori

    2012-01-01

    Rapid developments have taken place in biological/biomedical measurement and imaging technologies as well as in computer analysis and information technologies. The increase in data obtained with such technologies invites the reader into a virtual world that represents realistic biological tissue or organ structures in digital form and allows for simulation and what is called “in silico medicine.” This volume is the third in a textbook series and covers both the basics of continuum mechanics of biosolids and biofluids and the theoretical core of computational methods for continuum mechanics analyses. Several biomechanics problems are provided for better understanding of computational modeling and analysis. Topics include the mechanics of solid and fluid bodies, fundamental characteristics of biosolids and biofluids, computational methods in biomechanics analysis/simulation, practical problems in orthopedic biomechanics, dental biomechanics, ophthalmic biomechanics, cardiovascular biomechanics, hemodynamics...

  19. Morphology and biomechanics of human heart

    Science.gov (United States)

    Chelnokova, Natalia O.; Golyadkina, Anastasiya A.; Kirillova, Irina V.; Polienko, Asel V.; Ivanov, Dmitry V.

    2016-03-01

    Object of study: A study of the biomechanical characteristics of the human heart ventricles was performed. 80 hearts were extracted during autopsy of 80 corpses of adults (40 women and 40 men) aged 31-70 years. The samples were investigated in compliance with the recommendations of the ethics committee. Methods: Tension and compression tests were performed with help of the uniaxial testing machine Instron 5944. Cardiometry was also performed. Results: In this work, techniques for human heart ventricle wall biomechanical properties estimation were developed. Regularities of age and gender variability in deformative and strength properties of the right and left ventricle walls were found. These properties were characterized by a smooth growth of myocardial tissue stiffness and resistivity at a relatively low strain against reduction in their strength and elasticity from 31-40 to 61-70 years. It was found that tissue of the left ventricle at 61-70 years had a lower stretchability and strength compared with tissues of the right ventricle and septum. These data expands understanding of the morphological organization of the heart ventricles, which is very important for the development of personalized medicine. Taking into account individual, age and gender differences of the heart ventricle tissue biomechanical characteristics allows to rationally choosing the type of patching materials during reconstructive operations on heart.

  20. Basic biomechanic principles of knee instability.

    Science.gov (United States)

    Zlotnicki, Jason P; Naendrup, Jan-Hendrik; Ferrer, Gerald A; Debski, Richard E

    2016-06-01

    Motion at the knee joint is a complex mechanical phenomenon. Stability is provided by a combination of static and dynamic structures that work in concert to prevent excessive movement or instability that is inherent in various knee injuries. The anterior cruciate ligament (ACL) is a main stabilizer of the knee, providing both translational and rotatory constraint. Despite the high volume of research directed at native ACL function, pathogenesis and surgical reconstruction of this structure, a gold standard for objective quantification of injury and subsequent repair, has not been demonstrated. Furthermore, recent studies have suggested that novel anatomic structures may play a significant role in knee stability. The use of biomechanical principles and testing techniques provides essential objective/quantitative information on the function of bone, ligaments, joint capsule, and other contributing soft tissues in response to various loading conditions. This review discusses the principles of biomechanics in relation to knee stability, with a focus on the objective quantification of knee stability, the individual contributions of specific knee structures to stability, and the most recent technological advances in the biomechanical evaluation of the knee joint. PMID:27007474

  1. Biomechanics aspects of technique of high jump

    Directory of Open Access Journals (Sweden)

    Adashevskiy V.M.

    2013-02-01

    Full Text Available The purpose of work consists in the theoretical ground of optimum biomechanics descriptions in high jumps. A mathematical model is developed for determination of influence on the height of jump: speed and corner of flight of centre-of-mass during pushing away, positions of centre-of-mass body of sportsman in the phases of pushing away and transition through a slat, forces of resistance of air environment, influences of moment of inertia of body. The basic technical run-time errors of sportsman are selected exercises. To biomechanics descriptions, to the step-up effectiveness of high jumps belong: speed of flight of centre-of-mass sportsman (4.2-5.8 meters in a second, corner of flight of centre-of-mass body (50-58 degrees, height of flight of centre-of-mass body (0.85-1.15 meter. Directions of choice of necessary biomechanics descriptions which a sportsman can realize are shown. Offered recommendation on the increase of effectiveness of high jumps.

  2. Radiobiology in clinical radiation therapy - Part IV: Long term risks - Carcinogenic, hereditary, and teratogenetic effects

    International Nuclear Information System (INIS)

    The long-term risks induced by radiation are of much concern to patients and clinicians alike. As an example, perceived radiation risks are frequently cited in a woman's decision to choose a radical mastectomy over lumpectomy + radiation. In consequence, the actual radiation risks are often considerably overstated, or unreasonably downplayed. In this lecture we will discuss just what is known about the long term risks following radiotherapy, both from the human experience and from the laboratory. We will discuss risks both to the patient and to radiotherapy personnel. A good deal is known about the carcinogenic effects of high and low doses of radiation, in large part thanks to the careful study of the survivors of the atomic bombing in Japan, as well as studies of individuals exposed to medical x rays. It is possible to make an estimate, which is probably good to within a factor of, perhaps, three to five, of the cancer risks faced by a patient of a particular age and sex who is going to undergo a particular radiotherapeutic regimen. It is also possible to make an estimate of the risks faced by radiotherapy and nursing staff exposed to low doses. Brachytherapy related risk estimates are likely to be somewhat more uncertain, due to the poorly known sparing effects of the low dose rates used; for the radiotherapy personnel in brachytherapy, because of the doses which can be received, the risks can be quite significant. A recent complication in external-beam radiotherapy is the advent of high-energy linacs, which can produce a significant fast neutron dose which, dose for dose, may be ten to fifty times more carcinogenic than gamma rays. Data relating to the risks of hereditary effects of radiation come almost entirely from laboratory experiments in animals. Studies involving several million mice form the basis of most of our current understanding of hereditary effects. The results of these studies indicate that radiation is a relatively inefficient mutagen. The

  3. Carpal Ligament Anatomy and Biomechanics.

    Science.gov (United States)

    Pulos, Nicholas; Bozentka, David J

    2015-08-01

    A fundamental understanding of the ligamentous anatomy of the wrist is critical for any physician attempting to treat carpal instability. The anatomy of the wrist is complex, not only because of the number of named structures and their geometry but also because of the inconsistencies in describing these ligaments. The complex anatomy of the wrist is described through a review of the carpal ligaments and their effect on normal carpal motion. Mastery of this topic facilitates the physician's understanding of the patterns of instability that are seen clinically. PMID:26205699

  4. An introduction to biomechanics solids and fluids, analysis and design

    CERN Document Server

    Humphrey, Jay D

    2004-01-01

    Designed to meet the needs of undergraduate students, Introduction to Biomechanics takes the fresh approach of combining the viewpoints of both a well-respected teacher and a successful student. With an eye toward practicality without loss of depth of instruction, this book seeks to explain the fundamental concepts of biomechanics. With the accompanying web site providing models, sample problems, review questions and more, Introduction to Biomechanics provides students with the full range of instructional material for this complex and dynamic field.

  5. Biomechanics of the elbow joint in tennis players.

    OpenAIRE

    Eygendaal, D.; Rahussen, F.T.; Diercks, R.L.

    2007-01-01

    Elbow injuries constitute a sizeable percentage of tennis injuries. A basic understanding of biomechanics of tennis and analysis of forces, loads and motions of the elbow during tennis can will improve the understanding of the pathophysiology of these injuries. All different strokes in tennis have a different repetitive biomechanical nature which can result in tennis related injuries. In this article a biomechanically based evaluation of tennis strokes is presented. This overview includes all...

  6. Jet-Ricci Geometry of Time-Dependent Human Biomechanics

    OpenAIRE

    Ivancevic, Tijana T.

    2009-01-01

    We propose the time-dependent generalization of an `ordinary' autonomous human biomechanics, in which total mechanical + biochemical energy is not conserved. We introduce a general framework for time-dependent biomechanics in terms of jet manifolds derived from the extended musculo-skeletal configuration manifold. The corresponding Riemannian geometrical evolution follows the Ricci flow diffusion. In particular, we show that the exponential-like decay of total biomechanical energy (due to exh...

  7. THE STUDY ON BIOMECHANICAL RESPONSE OF DENTAL TISSUE IN CLINICAL CONDITION%正畸临床状态下的牙周组织力学响应分析

    Institute of Scientific and Technical Information of China (English)

    魏志刚; 汤文成; 严斌; 杨宝宽

    2012-01-01

    该文通过非线性有限元法研究在口腔正畸临床状态下的牙周组织力学响应。通过逆向工程方法将CT扫描获得图像建立起牙颌的三维有限元模型,使用牙周膜非线性本构模型,获得了在相邻牙齿作用下的牙颌组织的力学响应。分析了不同情况下牙齿相互作用力对正畸过程中牙周组织响应的影响,研究对比了牙颌骨的变形对牙齿位移的影响,最后使用数字散斑实验对数值模拟的结果进行了分析和验证。结果表明:牙齿之间的相互作用使得实际作用到牙周组织上的力有较大的变化;分析牙周组织的应力响应应该考虑牙齿之间的相互作用力。%The mechanical response of periodontal ligament in a clinical condition was analyzed in this paper with a nonlinear finite element method. A three-dimensional finite element model was built through the reverse engineering method with the images gained from CT scanning, and the mechanical response of dental tissue in a clinical condition was obtained with a nonlinear constitutive model of periodontal ligament. The influence of the interaction force between teeth on the mechanical response of periodontal ligament was analyzed, also did the influence of deformation of alveolar bone under a load on tooth displacements. A digital speckle experiment was conducted at last to testify the simulation result. The result shows that: the real force acted on the dental tissue is greatly influenced by the interaction force between teeth, thusly it is important indeed to use the force which is load onto the dental tissue to evaluate the dental response.

  8. Relationships between job organisational factors, biomechanical and psychosocial exposures.

    Science.gov (United States)

    Bao, Stephen S; Kapellusch, Jay M; Merryweather, Andrew S; Thiese, Matthew S; Garg, Arun; Hegmann, Kurt T; Silverstein, Barbara A

    2016-02-01

    The relationships between work organisational, biomechanical and psychosocial factors were studied using cross-sectional data from a pooled dataset of 1834 participants. The work organisational factors included: job rotation, overtime work, having second jobs and work pace. Task and job level biomechanical variables were obtained through sub-task data collected in the field or analysed in the laboratory. Psychosocial variables were collected based on responses to 10 questions. The results showed that job rotations had significant effects on all biomechanical and most psychosocial measures. Those with job rotations generally had higher job biomechanical stressors, and lower job satisfaction. Overtime work was associated with higher job biomechanical stressors, and possibly self-reported physical exhaustion. Those having second jobs reported getting along with co-workers well. Work pace had significant influences on all biomechanical stressors, but its impact on job biomechanical stressors and psychosocial effects are complicated. Practitioner Summary: The findings are based on a large number of subjects collected by three research teams in diverse US workplaces. Job rotation practices used in many workplaces may not be effective in reducing job biomechanical stressors for work-related musculoskeletal disorders. Overtime work is also associated with higher biomechanical stressors. PMID:26102483

  9. Biomechanics of the Optic Nerve Sheath in VIIP Syndrome

    Science.gov (United States)

    Ethier, C. Ross; Raykin, Julia; Gleason, Rudy; Mulugeta, Lealem; Myers, Jerry; Nelson, Emily; Samuels, Brian C.

    2014-01-01

    Long-duration space flight carries the risk of developing Visual Impairment and Intracranial Pressure (VIIP) syndrome, a spectrum of ophthalmic changes including posterior globe flattening, choroidal folds, distension of the optic nerve sheath (ONS), optic nerve kinking and potentially permanent degradation of visual function. The slow onset of VIIP, its chronic nature, and certain clinical features strongly suggest that biomechanical factors acting on the ONS play a role in VIIP. Here we measure several relevant ONS properties needed to model VIIP biomechanics. The ONS (meninges) of fresh porcine eyes (n7) was reflected, the nerve proper was truncated near the sclera, and the meninges were repositioned to create a hollow cylinder of meningeal connective tissue attached to the posterior sclera. The distal end was cannulated, sealed, and pressure clamped (mimicking cerebrospinal fluid [CSF] pressure), while the eye was also cannulated for independent control of intraocular pressure (IOP). The meninges were inflated (CSF pressure cycling 7-50 mmHg) while ONS outer diameter was imaged. In another set of experiments (n4), fluid permeation rate across the meninges was recorded by observing the drainage of an elevated fluid reservoir (30 mmHg) connected to the meninges. The ONS showed behavior typical of soft tissues: viscoelasticity, with hysteresis in early preconditioning cycles and repeatable behavior after 4 cycles, and nonlinear stiffening, particularly at CSF pressures 15 mmHg (Figure). Tangent moduli measured from the loading curve were 372 101, 1199 358, and 2050 379 kPa (mean SEM) at CSF pressures of 7, 15 and 30 mmHg, respectively. Flow rate measurements through the intact meninges at 30mmHg gave a permeability of 1.34 0.46 lmincm2mmHg (mean SEM). The ONS is a tough, strain-stiffening connective tissue that is surprisingly permeable. The latter observation suggests that there could be significant CSF drainage through the ONS into the orbit, likely important

  10. Variations in morphological and biomechanical indices at the distal radius in subjects with identical BMD

    OpenAIRE

    Kazakia, Galateia J.; Burghardt, Andrew J.; Link, Thomas M.; Majumdar, Sharmila

    2010-01-01

    Determination of osteoporotic status is based primarily on areal bone mineral density (aBMD) obtained through dual x-ray absorptiometry (DXA). However, many fractures occur in patients with T-scores above the WHO threshold of osteoporosis, in part because DXA measures are insensitive to biomechanically important alterations in bone quality. The goal of this study was to determine – within groups of subjects with identical radius aBMD values – the extant variation in densitometric, geometric, ...

  11. Biomechanical energy harvesting from human motion: theory, state of the art, design guidelines, and future directions

    OpenAIRE

    Shapiro Amir; Riemer Raziel

    2011-01-01

    Abstract Background Biomechanical energy harvesting from human motion presents a promising clean alternative to electrical power supplied by batteries for portable electronic devices and for computerized and motorized prosthetics. We present the theory of energy harvesting from the human body and describe the amount of energy that can be harvested from body heat and from motions of various parts of the body during walking, such as heel strike; ankle, knee, hip, shoulder, and elbow joint motio...

  12. BIOMECHANICS OF FLIGHT PHASE WHEN RUNNING LONG JUMP FROM PLACE OF DIFFERENT QUALIFICATION SPORTSMEN

    OpenAIRE

    A. V. Razuvanova; Ye. V. Koshelskaya; V. I. Andreyev; I. V. Kapilevich

    2015-01-01

    Biomechanical features of flight phase when running long jump from place of different qualification sportsmen were investigated by method of Motion Tracking. The obtained results showed that the effective control of body position during the phase of flight can improve the effectiveness of jump actions.. This control is performed by moving parts of the body – bending legs at the knee, extension in the hip joints, the joints of the spine, shoulder joints and, as a consequence, any additional to...

  13. Biomechanics of the Metalloceramic Bridge Prostheses at the Dental Row Lateral Department Small Defect Substitution

    OpenAIRE

    Zhulyov E.N.; Sulyagina O.V.; Leontiev N.V.

    2009-01-01

    A method of mathematical simulation was used for prosthetics improvement of patients with the dental row lateral department small defects by combined bridge prostheses with a support on insets. Four types of the metalloceramic bridge prosthesis constructions were used at a study of a biomechanics in a system of ″bridge prosthesis—supporting teeth—periodontium—alveolar part of a jaw″. The investigation results have demonstrated that a distribution of elastic tensions is unfavorable and can cau...

  14. Anthropometry and Biomechanics Facility Spring 2016 Internship

    Science.gov (United States)

    Boppana, Abhishektha

    2016-01-01

    The Anthropometry and Biomechanics Facility (ABF) at Johnson Space Center supports the Space Human Factors Engineering portfolio of the Human Research Program. ABF provides capability to verify the accommodation and comfort of crewmembers through anthropometry and biomechanics analyses. Anthropometric measurements are derived from three-dimensional (3D) whole body scan images. The scans are currently taken by a Human Solutions Vitus 3D Laser Scanning System. ABF has purchased a 3dMD photogrammetry scanner system to speed up the process of collecting 3D scans. The photogrammetry scanner system features a faster data collection time, as well as fewer holes in the scans. This internship was mainly focused on developing calibration, measurement, data acquisition, and analysis processes for the new system. In addition, I also participated in a project to validate the use of a pressure mat sensor on the shoulder during in-suit testing. My duties for the scanner validation project started with identifying and documenting a calibration process. The calibration process proved vital to using the system as the quality of the scans was directly related to the success of the calibration. In addition, the calibration process suggested by the system vendor required the user to hold a large calibration board at precise locations. To aid in this, I built a calibration stand which held a calibration board at constant positions throughout numerous calibration process. The calibration process was tested extensively until proven acceptable. The standardized process reduced calibration time from over 10 minutes to just below three minutes. As a result, the calibration process could be completed painlessly and precisely, and scan quality was constant between sessions. After standardizing the calibration process, I proceeded to modify the locations of the cameras in order to capture the full volume of a person. The scanning system needed to capture a full T-pose of a person in one scan

  15. Role of biomechanics in the understanding of normal, injured, and healing ligaments and tendons

    Directory of Open Access Journals (Sweden)

    Jung Ho-Joong

    2009-05-01

    Full Text Available Abstract Ligaments and tendons are soft connective tissues which serve essential roles for biomechanical function of the musculoskeletal system by stabilizing and guiding the motion of diarthrodial joints. Nevertheless, these tissues are frequently injured due to repetition and overuse as well as quick cutting motions that involve acceleration and deceleration. These injuries often upset this balance between mobility and stability of the joint which causes damage to other soft tissues manifested as pain and other morbidity, such as osteoarthritis. The healing of ligament and tendon injuries varies from tissue to tissue. Tendinopathies are ubiquitous and can take up to 12 months for the pain to subside before one could return to normal activity. A ruptured medial collateral ligament (MCL can generally heal spontaneously; however, its remodeling process takes years and its biomechanical properties remain inferior when compared to the normal MCL. It is also known that a midsubstance anterior cruciate ligament (ACL tear has limited healing capability, and reconstruction by soft tissue grafts has been regularly performed to regain knee function. However, long term follow-up studies have revealed that 20–25% of patients experience unsatisfactory results. Thus, a better understanding of the function of ligaments and tendons, together with knowledge on their healing potential, may help investigators to develop novel strategies to accelerate and improve the healing process of ligaments and tendons. With thousands of new papers published in the last ten years that involve biomechanics of ligaments and tendons, there is an increasing appreciation of this subject area. Such attention has positively impacted clinical practice. On the other hand, biomechanical data are complex in nature, and there is a danger of misinterpreting them. Thus, in these review, we will provide the readers with a brief overview of ligaments and tendons and refer them to

  16. Recommendations for conducting controlled clinical studies of dental restorative materials. Science Committee Project 2/98--FDI World Dental Federation study design (Part I) and criteria for evaluation (Part II) of direct and indirect restorations including onlays and partial crowns.

    Science.gov (United States)

    Hickel, Reinhard; Roulet, Jean-François; Bayne, Stephen; Heintze, Siegward D; Mjör, Ivar A; Peters, Mathilde; Rousson, Valentin; Randall, Ros; Schmalz, Gottfried; Tyas, Martin; Vanherle, Guido

    2007-01-01

    About 35 years ago, Ryge provided a practical approach to the evaluation of the clinical performance of restorative materials. This systematic approach was soon universally accepted. While that methodology has served us well, a large number of scientific methodologies and more detailed questions have arisen that require more rigor. Current restorative materials have vastly improved clinical performance, and any changes over time are not easily detected by the limited sensitivity of the Ryge criteria in short-term clinical investigations. However, the clinical evaluation of restorations not only involves the restorative material per se but also different operative techniques. For instance, a composite resin may show good longevity data when applied in conventional cavities but not in modified operative approaches. Insensitivity, combined with the continually evolving and nonstandard investigator modifications of the categories, scales, and reporting methods, has created a body of literature that is extremely difficult to interpret meaningfully. In many cases, the insensitivity of the original Ryge methods leads to misinterpretation as good clinical performance. While there are many good features of the original system, it is now time to move on to a more contemporary one. The current review approaches this challenge in two ways: (1) a proposal for a modern clinical testing protocol for controlled clinical trials, and (2) an in-depth discussion of relevant clinical evaluation parameters, providing 84 references that are primarily related to issues or problems for clinical research trials. Together, these two parts offer a standard for the clinical testing of restorative materials/procedures and provide significant guidance for research teams in the design and conduct of contemporary clinical trials. Part 1 of the review considers the recruitment of subjects, restorations per subject, clinical events, validity versus bias, legal and regulatory aspects, rationales for

  17. Spinal biomechanics and functional anatomy.

    Science.gov (United States)

    Denoix, J M

    1999-04-01

    Knowledge of the normal functional behavior and mechanical properties of the vertebral column is important to understand the pathogenesis of back lesions, to identify the clinical manifestations of back pain, and to ensure a rational approach to physical therapy. The purpose of this article is to present a synthesis of in vivo and in vitro data obtained from different but complementary investigations. Presently, in vivo studies are limited; few gait-specific kinematic and electromyographic investigations are in process. Higher stresses to reach the maximal range of intervertebral motion can be applied on the spine on anatomical specimens than in living horses, and anatomical functional data can be obtained at the level of intervertebral structures. For each movement of flexion, extension, lateroflexion, and rotation, regional and intervertebral mobility is presented with an emphasis on craniocaudal variations and their anatomical causes. Because of the location of their ICR, the dorsoventral movements of a thoracolumbar intervertebral joint can be defined as a rotation around the center of the more caudal vertebral body. This information supports the new concept of intervertebral mobility in the horse and provides additional elements to facilitate understanding of the pathogenesis of back problems in the horse. PMID:10218240

  18. Clinical picture and treatment of complications of lower part of large intestine resulting from radiotherapy for intra-pelvic cancer

    International Nuclear Information System (INIS)

    The authors described clinical pictures and those treatments of 40 patients with complications of the lower part of the large intestine resulting from radiotherapy for cancer of the uterus, ovarium or the penis. As the radiotherapy, 60Co-telecobalt (6,000-16,000R) and 60Co-needle (1,000-8,568 mch) intracavitary irradiation were used alone or in combination. Findings in the complications of the lower part of the large intestine were classified into Grade I (13 cases), II (14), III (14), and IV (4) according to Sherman. The prodromal symptoms of the complications appeared in 2-6 months following the irradiation in more than a half of the patients, and it appeared within a year in most of the patients. Most of the patients complained about melena, anemia, proctagra, tenesmus and diarrhea. In the cases of Grade III, the symptoms of ileus such as constipation, abdominal distention, and abdominal pain appeared. Internal treatment was given principally, and preternal anus was made when frequent blood transfusion was required. Fourteen cases of those in Grade I and II recovered within 1-3 years. The cases which received proctostomy, including those who had bleeding, stricture and fistulation, had favorable prognosis. This result suggested that the radiotherapy for intra-pelvic cancer should be controlled to prevent further development of the complications in the rectum beyond Grade I. (Serizawa, K.)

  19. Three-dimensional finite element analysis of lumbar vertebra loaded by static stress and its biomechanical significance

    Institute of Scientific and Technical Information of China (English)

    SU Jia-can; LI Zhuo-dong; CAO Lie-hu; YU Bao-qing; ZHANG Chun-cai; LI Ming

    2009-01-01

    To explore the mechanical behavioroflum-bar spine loaded by stress and provide the mechanical ba-sis for clinical analysis and judgement of lumbar spine frac-tare classification, mechanical distribution and static stress. Methods: By means of computer simulation method, the constructed lumbar spine three-dimensional model was introduced into three-dimensional finite element analysis by software Ansys 7.0. The lumbar spine mechanical be-havior in different parts of the stress loading were calculated. Impact load is 0-8000 N. The peak value was 8000 N. The loading time is 0-40 minutes. The values of the main stress, stress distribution and the lumbar spine unit displacement in the direction of main stress were analyzed. Results: The lumbar spine model was divided into a total of 121 239 nodes, 112 491 units. It could objectively reflect the true anatomy of lumbar spine and its biomechani-cal behavior and obtain the end-plate images under differ-ent stress. The stress distribution on the lumbar interverte-bral disc (L-L) under the axial, lateral flexion and extension stress, and the displacement trace of the corresponding pro-cessus articularis were analyzed. Conclusion: It is helpful to analyze the stress distribu-tion of lumbar spine and units displacement in static stress loading in the clinical research of lumbar spine injury and the distribution of internal stress.

  20. Biomechanics, Exercise Physiology, and the 75th Anniversary of RQES

    Science.gov (United States)

    Hamill, Joseph; Haymes, Emily M.

    2005-01-01

    The purpose of this paper is to review the biomechanics and exercise physiology studies published in the Research Quarterly for Exercise and Sport (RQES) over the past 75 years. Studies in biomechanics, a relatively new subdiscipline that evolved from kinesiology, first appeared in the journal about 40 years ago. Exercise physiology studies have…

  1. Factors Related to Students' Learning of Biomechanics Concepts

    Science.gov (United States)

    Hsieh, ChengTu; Smith, Jeremy D.; Bohne, Michael; Knudson, Duane

    2012-01-01

    The purpose of this study was to replicate and expand a previous study to identify the factors that affect students' learning of biomechanical concepts. Students were recruited from three universities (N = 149) located in the central and western regions of the United States. Data from 142 students completing the Biomechanics Concept Inventory…

  2. The Undergraduate Biomechanics Experience at Iowa State University.

    Science.gov (United States)

    Francis, Peter R.

    This paper discusses the objectives of a program in biomechanics--the analysis of sports skills and movement--and the evolution of the biomechanics program at Iowa State University. The primary objective of such a course is to provide the student with the basic tools necessary for adequate analysis of human movement, with special emphasis upon…

  3. Biomechanics aspects of technique of high jump

    OpenAIRE

    Adashevskiy V.M.; Iermakov S.S.; Marchenko A. A.

    2013-01-01

    The purpose of work consists in the theoretical ground of optimum biomechanics descriptions in high jumps. A mathematical model is developed for determination of influence on the height of jump: speed and corner of flight of centre-of-mass during pushing away, positions of centre-of-mass body of sportsman in the phases of pushing away and transition through a slat, forces of resistance of air environment, influences of moment of inertia of body. The basic technical run-time errors of sportsma...

  4. High resolution extremity CT for biomechanics modeling

    International Nuclear Information System (INIS)

    With the advent of ever more powerful computing and finite element analysis (FEA) capabilities, the bone and joint geometry detail available from either commercial surface definitions or from medical CT scans is inadequate. For dynamic FEA modeling of joints, precise articular contours are necessary to get appropriate contact definition. In this project, a fresh cadaver extremity was suspended in parafin in a lucite cylinder and then scanned with an industrial CT system to generate a high resolution data set for use in biomechanics modeling

  5. Distributed Data Acquisition For Biomechanics Research

    Science.gov (United States)

    Myklebust, J.; Geisler, M.; Prieto, T.; Weiss, R.

    1987-01-01

    Biomechanics research at the Medical College of Wisconsin is directed to the determination of the mechanisms of head and spine injury and the evaluation of surgical treatments for these injuries. This work involves mechanical testing of components of the spine (disks, vertebral bodies, and ligaments) as well as testing of composite spines and in situ evaluation of intact human cadavers (1,3). Other studies utilize experimental animals to measure neurologic and physiologic effects due to injury producing loads and accelerations (2). An integrated system has been developed to facilitate the acquisition and analysis of the diverse types of data from these experiments.

  6. Pathophysiology and Biomechanics of the Aging Spine

    Science.gov (United States)

    Papadakis, Michael; Sapkas, Georgios; Papadopoulos, Elias C; Katonis, Pavlos

    2011-01-01

    Aging of the spine is characterized by two parallel but independent processes: the reduction of bone mineral density and the development of degenerative changes. The combination of degeneration and bone mass reduction contribute, to a different degree, to the development of a variety of lesions. This results in a number of painful and often debilitating disorders. The present review constitutes a synopsis of the pathophysiological processes that take place in the aging spine as well as of the consequences these changes have on the biomechanics of the spine. The authors hope to present a thorough yet brief overview of the process of aging of the human spine. PMID:21966338

  7. Jet Methods in Time-Dependent Lagrangian Biomechanics

    CERN Document Server

    Ivancevic, Tijana T

    2009-01-01

    In this paper we propose the time-dependent generalization of an `ordinary' autonomous human biomechanics, in which total mechanical + biochemical energy is not conserved. We introduce a general framework for time-dependent biomechanics in terms of jet manifolds associated to the extended musculo-skeletal configuration manifold, called the configuration bundle. We start with an ordinary configuration manifold of human body motion, given as a set of its all active degrees of freedom (DOF) for a particular movement. This is a Riemannian manifold with a material metric tensor given by the total mass-inertia matrix of the human body segments. This is the base manifold for standard autonomous biomechanics. To make its time-dependent generalization, we need to extend it with a real time axis. By this extension, using techniques from fibre bundles, we defined the biomechanical configuration bundle. On the biomechanical bundle we define vector-fields, differential forms and affine connections, as well as the associat...

  8. Biomechanical factors associated with the development of tibiofemoral knee osteoarthritis

    DEFF Research Database (Denmark)

    van Tunen, Joyce A C; Dell'Isola, Andrea; Juhl, Carsten;

    2016-01-01

    INTRODUCTION: Altered biomechanics, increased joint loading and tissue damage, might be related in a vicious cycle within the development of knee osteoarthritis (KOA). We have defined biomechanical factors as joint-related factors that interact with the forces, moments and kinematics in and around...... a synovial joint. Although a number of studies and systematic reviews have been performed to assess the association of various factors with the development of KOA, a comprehensive overview focusing on biomechanical factors that are associated with the development of KOA is not available. The aim...... of this review is (1) to identify biomechanical factors that are associated with (the development of) KOA and (2) to identify the impact of other relevant risk factors on this association. METHODS AND ANALYSIS: Cohort, cross-sectional and case-control studies investigating the association of a biomechanical...

  9. Biomechanical Comparison of Spinal Fusion Methods Using Interspinous Process Compressor and Pedicle Screw Fixation System Based on Finite Element Method

    Science.gov (United States)

    Choi, Jisoo; Kim, Sohee

    2016-01-01

    Objective To investigate the biomechanical effects of a newly proposed Interspinous Process Compressor (IPC) and compare with pedicle screw fixation at surgical and adjacent levels of lumbar spine. Methods A three dimensional finite element model of intact lumbar spine was constructed and two spinal fusion models using pedicle screw fixation system and a new type of interspinous devices, IPC, were developed. The biomechanical effects such as range of motion (ROM) and facet contact force were analyzed at surgical level (L3/4) and adjacent levels (L2/3, L4/5). In addition, the stress in adjacent intervertebral discs (D2, D4) was investigated. Results The entire results show biomechanical parameters such as ROM, facet contact force, and stress in adjacent intervertebral discs were similar between PLIF and IPC models in all motions based on the assumption that the implants were perfectly fused with the spine. Conclusion The newly proposed fusion device, IPC, had similar fusion effect at surgical level, and biomechanical effects at adjacent levels were also similar with those of pedicle screw fixation system. However, for clinical applications, real fusion effect between spinous process and hooks, duration of fusion, and influence on spinous process need to be investigated through clinical study. PMID:26962413

  10. A prática clínica baseada em evidências. Parte I: questões clínicas bem construídas Evidence based clinical practice. Part 1: well structured clinical questions

    Directory of Open Access Journals (Sweden)

    Moacyr Roberto Cuce Nobre

    2003-01-01

    Full Text Available Na prática diária as decisões tomadas para resolver o problema do paciente são usualmente baseadas na aplicação consciente da informação avaliável por regras explicitamente definidas. A prática clínica baseada em evidências leva em consideração o reconhecimento dos conhecimentos explícitos e tácitos, entendendo que é impossível tornar explícito todos os aspectos da competência profissional. A dúvida passa a fazer parte do processo de decisão, inicialmente na identificação dos componentes inconscientes envolvidos, e em seguida na análise do conhecimento explícito utilizado nesse processo. Ao elaborarmos uma questão clínica estruturada e que possa ser respondida, devemos lembrar que essa dúvida pode estar relacionada a aspectos básicos e de definição da doença ou relacionada ao atendimento do paciente, como em diagnóstico, terapêutica ou prognóstico. Ao longo de nossa vida médica, ambos os tipos de questões estão presentes, variando na proporção em que nossa experiência aumenta à medida do tempo de prática clínica. O processo de encontrar resposta apropriada à dúvida surgida no atendimento depende da forma como estruturamos as partes deste processo. A forma preconizada é conhecida pela sigla PICO. formada por P de paciente ou população, I de intervenção ou indicador, C de comparação ou controle e O de "outcome", que na língua inglesa significa desfecho clínico, resultado, ou por fim, a resposta que se espera encontrar nas fontes de informação científica. Esta é a primeira condição básica para que a nossa busca possa ser bem sucedida, a segunda é encontrar as palavras-chaves que melhor descrevem cada uma destas quatro características da questão. Sem estes cuidados as pesquisas em bases de dados informatizadas costuma resultar em ausência de informação ou em quantidade muito grande de informação que não está relacionada com o nosso interesse.Clinical decisions in daily practice

  11. Biomechanical Analysis of Pedicle Screw Fixation for Thoracolumbar Burst Fractures.

    Science.gov (United States)

    McDonnell, Matthew; Shah, Kalpit N; Paller, David J; Thakur, Nikhil A; Koruprolu, Sarath; Palumbo, Mark A; Daniels, Alan H

    2016-05-01

    Treatment of unstable thoracolumbar burst fractures remains controversial. Long-segment pedicle screw constructs may be stiffer and impart greater forces on adjacent segments compared with short-segment constructs, which may affect clinical performance and long-term out come. The purpose of this study was to biomechanically evaluate long-segment posterior pedicle screw fixation (LSPF) vs short-segment posterior pedicle screw fixation (SSPF) for unstable burst fractures. Six unembalmed human thoracolumbar spine specimens (T10-L4) were used. Following intact testing, a simulated L1 burst fracture was created and sequentially stabilized using 5.5-mm titanium polyaxial pedicle screws and rods for 4 different constructs: SSPF (1 level above and below), SSPF+L1 (pedicle screw at fractured level), LSPF (2 levels above and below), and LSPF+L1 (pedicle screw at fractured level). Each fixation construct was tested in flexion-extension, lateral bending, and axial rotation; range of motion was also recorded. Two-way repeated-measures analysis of variance was performed to identify differences between treatment groups and functional noninstrumented spine. Short-segment posterior pedicle screw fixation did not achieve stability seen in an intact spine (P.1). Long-segment posterior pedicle screw fixation constructs were not associated with increased adjacent segment motion. Al though the sample size of 6 specimens was small, this study may help guide clinical decisions regarding burst fracture stabilization. [Orthopedics. 2016; 39(3):e514-e518.]. PMID:27135451

  12. Nanatsu-no-kata, Endō-no-kata, and Jōge-no-kata ―A pedagogical and qualitative biomechanical evaluation of Hirano Tokio’s kuzushi (unbalancing concept as part of skill acquisition for throwing techniques in Kōdōkan jūdō

    Directory of Open Access Journals (Sweden)

    Carl De Crée

    2014-06-01

    Full Text Available Hirano Tokio (1922-1993 was a talented jūdō champion who developed his own pedagogical approach towards teaching and practicing kuzushi (unbalancing and tsukuri (preparation, two critical skills for successfully applying jūdō throws. In his approach, Hirano emphasizes the use of rotational unbalancing preceded by strategic movements that mimic water waves. No biomechanical analysis of Hirano’s wave system has previously been attempted. The purpose of this paper is to provide a detailed survey of Hirano’s didactic system comparing it with traditional Kōdōkan teachings, and to assess its biomechanical foundations. The fluid dynamic modeling of the several kinds of waves proposed by Hirano is mathematically complicated and heavily relies on Boussinesq differential equations. Given the involvement of numerous parameters in determining the hydrodynamic behavior of water (depth, period of waves, saliency, temperatures, currents, shape of the coastal line, water density, wind which are absent in the surroundings of a pair of two jūdōka moving indoors on a tatami, Hirano’s system appears limited to a mere visualization and metaphysical interpretation of jūdō. The lack of empirical and experimental data available obtained in large groups of students taught according to Hirano’s approach make it so far impossible to conclude whether it facilitates kuzushi and tsukuri skill acquisition. Ultimately Hirano’s wave-based kuzushi/tsukuri does not alter the biomechanical analysis previously proposed by Sacripanti, as it still is all about general action invariants aimed to close the distance between both opponents, to break the opponent’s symmetry, and to apply one of the infinite options to achieve this.

  13. Inframammary Fold Reconstruction: A Biomechanical Analysis

    Science.gov (United States)

    Schell, Julia; Uener, Jens; Prescher, Andreas; Scaal, Martin; Puppe, Julian; Warm, Mathias

    2016-01-01

    Background: Inframammary fold reconstruction has scarcely been evaluated in literature. No biomechanical analyses have been performed comparing different reconstructive methods. This evaluation compares the gold-standard suture reconstruction with an intrarib anchor system (Micro BioComposite SutureTak, Arthrex). Methods: Three analysis groups were compared including 8 Sawbone blocks, 22 embalmed cadaver, and 27 regular cadaver specimens (N = 57). Transient mechanical analysis was performed at 5 N/s using an Instron 5565 test frame. Results: Ultimate load favored the anchor system (compared with the gold-standard suture) by a factor of 9.8 (P group and a factor of 1.7 (P group. A similar statistically significant benefit was shown for stiffness and load at 2-mm displacement. Conclusions: This analysis showed an anchor system to be the biomechanically superior fixation method in terms of ultimate load, fixation stiffness, and displacement at failure when compared with the gold-standard suture method in inframammary fold reconstruction. Because of superior stability in every aspect, an anchor system may be considered for inframammary fold reconstruction. PMID:27257564

  14. Integrated biomechanical and topographical surface characterization (IBTSC)

    Energy Technology Data Exchange (ETDEWEB)

    Löberg, Johanna, E-mail: Johanna.Loberg@dentsply.com [Dentsply Implants, Box 14, SE-431 21 Mölndal (Sweden); Mattisson, Ingela [Dentsply Implants, Box 14, SE-431 21 Mölndal (Sweden); Ahlberg, Elisabet [Department of Chemistry and Molecular Biology, University of Gothenburg, SE-41296 Gothenburg (Sweden)

    2014-01-30

    In an attempt to reduce the need for animal studies in dental implant applications, a new model has been developed which combines well-known surface characterization methods with theoretical biomechanical calculations. The model has been named integrated biomechanical and topographical surface characterization (IBTSC), and gives a comprehensive description of the surface topography and the ability of the surface to induce retention strength with bone. IBTSC comprises determination of 3D-surface roughness parameters by using 3D-scanning electron microscopy (3D-SEM) and atomic force microscopy (AFM), and calculation of the ability of different surface topographies to induce retention strength in bone by using the local model. Inherent in this integrated approach is the use of a length scale analysis, which makes it possible to separate different size levels of surface features. The IBTSC concept is tested on surfaces with different level of hierarchy, induced by mechanical as well as chemical treatment. Sequential treatment with oxalic and hydrofluoric acid results in precipitated nano-sized features that increase the surface roughness and the surface slope on the sub-micro and nano levels. This surface shows the highest calculated shear strength using the local model. The validity, robustness and applicability of the IBTSC concept are demonstrated and discussed.

  15. Biomechanical Energy Harvester Design For Active Prostheses

    Directory of Open Access Journals (Sweden)

    Akın Oğuz Kaptı

    2012-06-01

    Full Text Available One of the factors restricting the functions of active prostheses is limited charge times and weights of the batteries. Therefore, some biomechanical energy harvesting studies are conducted for reducing the dependence on batteries and developing the systems that produce energy by utilizing one's own actions during daily living activities. In this study, as a new approach to meet energy needs of active-controlled lower limb prostheses, the design of a biomechanical energy harvester that produces electrical energy from the movements of the knee joint during gait were carried out. This harvester is composed of the generator, planetary gear system and one-way clutch that transmit just the knee extension. Low weight, low additional metabolic power consumption requirement and high electrical power generation are targeted in design process. The total reduction ratio of the transmission is 104, and the knee joint reaction torque applied by the system is 6 Nm. Average electrical powers that can be obtained are 17 W and 5,8 W for the swing extension phase and the entire cycle, respectively. These values seem to be sufficient for charging the battery units of many prostheses and similar medical systems, and portable electronic devices such as mobile phones, navigation devices and laptops.

  16. Are biomechanical changes necessary for tumor progression?

    Science.gov (United States)

    Kas, Josef A.; Fritsch, Anatol; Kiessling, Tobias; Nnetu, David K.; Pawlizak, Steve; Wetzel, Franziska; Zink, Mareike

    2011-03-01

    With an increasing knowledge in tumor biology an overwhelming complexity becomes obvious which roots in the diversity of tumors and their heterogeneous molecular composition. Nevertheless in all solid tumors malignant neoplasia, i.e. uncontrolled growth, invasion of adjacent tissues, and metastasis, occurs. Physics sheds some new light on cancer by approaching this problem from a functional, materials perspective. Recent results indicate that all three pathomechanisms require changes in the active and passive cellular biomechanics. Malignant transformation causes cell softening for small deformations which correlates with an increased rate of proliferation and faster cell migration. The tumor cell's ability to strain harden permits tumor growth against a rigid tissue environment. A highly mechanosensitive, enhanced cell contractility is a prerequisite that tumor cells can cross its tumor boundaries and that this cells can migrate through the extracellular matrix. Insights into the biomechanical changes during tumor progression may lead to selective treatments by altering cell mechanics. Such drugs would not cure by killing cancer cells, but slow down tumor progression with only mild side effects and thus may be an option for older and frail patients.

  17. Integrated biomechanical and topographical surface characterization (IBTSC)

    Science.gov (United States)

    Löberg, Johanna; Mattisson, Ingela; Ahlberg, Elisabet

    2014-01-01

    In an attempt to reduce the need for animal studies in dental implant applications, a new model has been developed which combines well-known surface characterization methods with theoretical biomechanical calculations. The model has been named integrated biomechanical and topographical surface characterization (IBTSC), and gives a comprehensive description of the surface topography and the ability of the surface to induce retention strength with bone. IBTSC comprises determination of 3D-surface roughness parameters by using 3D-scanning electron microscopy (3D-SEM) and atomic force microscopy (AFM), and calculation of the ability of different surface topographies to induce retention strength in bone by using the local model. Inherent in this integrated approach is the use of a length scale analysis, which makes it possible to separate different size levels of surface features. The IBTSC concept is tested on surfaces with different level of hierarchy, induced by mechanical as well as chemical treatment. Sequential treatment with oxalic and hydrofluoric acid results in precipitated nano-sized features that increase the surface roughness and the surface slope on the sub-micro and nano levels. This surface shows the highest calculated shear strength using the local model. The validity, robustness and applicability of the IBTSC concept are demonstrated and discussed.

  18. The corneoscleral shell of the eye: potentials of assessing biomechanical parameters in normal and pathological conditions

    Directory of Open Access Journals (Sweden)

    E. N. Iomdina

    2016-01-01

    Full Text Available The paper reviews modern methods of evaluating the biomechanical properties of the corneoscleral shell of the eye that can be used both in the studies of the pathogenesis of various ophthalmic pathologies and in clinical practice. The biomechanical parameters of the cornea and the sclera have been shown to be diagnostically significant in assessing the risk of complications and the effectiveness of keratorefractive interventions, in the diagnosis and the prognosis of keratoconus, progressive myopia, or glaucoma. In clinical practice, a special device, Ocular Response Analyzer (ORA, has been used on a large scale. The analyzer is used to assess two parameters that characterize viscoelastic properties of the cornea — corneal hysteresis (CH and corneal resistance factor (CRF. Reduced levels of CH and CRF have been noted after eximer laser surgery, especially that administered to patients who demonstrate a regression in the refraction effect or suffer from keratoconus. This fact justifies the use of these biomechanical parameters as additional diagnostic criteria in the evaluation of the state of the cornea. At the same time, ORA data are shown to reflect the biomechanical response to the impact of the air pulse not only from the cornea alone but also from the whole corneoscleral capsule. This is probably the cause of reduced CH in children with progressive myopia and a weakened supportive function of the sclera, as well as such reduction in glaucomatous adult patients. It is hypothesized that a low CH value is a result of remodeling of the connective tissue matrix of the corneoscleral shell of the eye and can be an independent factor testifying to a risk of glaucoma progression. Reduced CH in primary open-angle glaucoma occurs in parallel with the development of pathological structural changes of the optic disc, and deterioration of visual fields, which is an evidence of a specific character and sensitivity of this parameter. The

  19. The biomechanics of upper extremity kinematic and kinetic modeling: applications to rehabilitation engineering.

    Science.gov (United States)

    Slavens, Brooke A; Harris, Gerald F

    2008-01-01

    Human motion analysis has evolved from the lower extremity to the upper extremity. Rehabilitation engineering is reliant upon three-dimensional biome-chanical models for a thorough understanding of upper body motions and forces in order to improve treatment methods, rehabilitation strategies and to prevent injury. Due to the complex nature of upper body movements, a standard biomechanical model does not exist. This paper reviews several kinematic and kinetic rehabilitation engineering models from the literature. These models may capture a single joint; multijoints such as the shoulder, elbow and wrist; or a combination of joints and an ambulatory aid, which serves as the extension of the upper arm. With advances in software and hardware, new models continuously arise due to the clinical questions at hand. When designing a biomechanical upper extremity model, several key components must be determined. These include deciding on the anatomic segments of the model, the number of markers and placement on bony landmarks, the definition of joint coordinate systems, and the description of the joint motions. It is critical to apply the proper model to further our understanding of pathologic populations. PMID:19740069

  20. Biomechanical rupture risk assessment of abdominal aortic aneurysms based on a novel probabilistic rupture risk index.

    Science.gov (United States)

    Polzer, Stanislav; Gasser, T Christian

    2015-12-01

    A rupture risk assessment is critical to the clinical treatment of abdominal aortic aneurysm (AAA) patients. The biomechanical AAA rupture risk assessment quantitatively integrates many known AAA rupture risk factors but the variability of risk predictions due to model input uncertainties remains a challenging limitation. This study derives a probabilistic rupture risk index (PRRI). Specifically, the uncertainties in AAA wall thickness and wall strength were considered, and wall stress was predicted with a state-of-the-art deterministic biomechanical model. The discriminative power of PRRI was tested in a diameter-matched cohort of ruptured (n = 7) and intact (n = 7) AAAs and compared to alternative risk assessment methods. Computed PRRI at 1.5 mean arterial pressure was significantly (p = 0.041) higher in ruptured AAAs (20.21(s.d. 14.15%)) than in intact AAAs (3.71(s.d. 5.77)%). PRRI showed a high sensitivity and specificity (discriminative power of 0.837) to discriminate between ruptured and intact AAA cases. The underlying statistical representation of stochastic data of wall thickness, wall strength and peak wall stress had only negligible effects on PRRI computations. Uncertainties in AAA wall stress predictions, the wide range of reported wall strength and the stochastic nature of failure motivate a probabilistic rupture risk assessment. Advanced AAA biomechanical modelling paired with a probabilistic rupture index definition as known from engineering risk assessment seems to be superior to a purely deterministic approach. PMID:26631334

  1. Fibras reforçadas por resina (FRC em Ortodontia. Versatilidade clínica: parte 2 Fiber reinforced composite (FRC in Orthodontic. Clinical versatility: part II

    Directory of Open Access Journals (Sweden)

    Daniel Ianni Filho

    2005-06-01

    Full Text Available As fibras de vidro e de polietileno podem ser utilizadas na prática ortodôntica em diversas situações clínicas, nos casos com ou sem extrações dentárias. Este artigo tem como objetivo mostrar algumas das aplicações clínicas nas quais as fibras contribuíram de forma significativa para a realização dos tratamentos ortodônticos, simplificando-os e aumentando a eficiência clínica. As fibras foram utilizadas principalmente em segmentos de ancoragem e na substituição da banda pela colagem da associação fibra/tubo nos molares.Glass and polyethylene fibers can be used in orthodontic practice on several clinical(s situations, in cases with or without teeth extraction. The objective of this article is to show some of the clinical applications in which the fibers contributed in a positive way to improve the performance of orthodontic treatments, simplifying and raiseing the clinical efficiency. These fibers were mainly used on anchorage segments, and as a substitute for the band by bonding the fiber/tube association in molars.

  2. Biomechanical risk factors of non-contact ACL injuries:A stochastic biomechanical modeling study

    Institute of Scientific and Technical Information of China (English)

    Cheng-Feng; Lin; Hui; Liu; Michael; T.Gros; Paul; Weinhold; William; E.Garrett; Bing; Yu

    2012-01-01

    <正>Background:Significant efforts have been made to identify modifiable risk factors of non-contact anterior cruciate ligament(ACL) injuries in male and female athletes.However,current literature on the risk factors for ACL injury are purely descriptive.An understanding of biomechanical relationship between risk and risk factors of the non-contact ACL injury is necessary to develop effective prevention programs. Purpose:To compare lower extremity kinematics and kinetics between trials with and without non-contact ACL injuries and to determine if any difference exists between male and female trials with non-contact ACL injuries regarding the lower extremity motion patterns. Methods:In this computer simulation study,a stochastic biomechanical model was used to estimate the ACL loading at the time of peak posterior ground reaction force(GRF) during landing of the stop-jump task.Monte Carlo simulations were performed to simulate the ACL injuries with repeated random samples of independent variables.The distributions of independent variables were determined from in vivo laboratory data of 40 male and 40 female recreational athletes. Results:In the simulated injured trials,both male and female athletes had significantly smaller knee flexion angles,greater normalized peak posterior and vertical GRF.greater knee valgus moment,greater patella tendon force,greater quadriceps force,greater knee extension moment. and greater proximal tibia anterior shear force in comparison to the simulated uninjured trials.No significant difference was found between genders in any of the selected biomechanical variables in the trials with simulated non-contact ACL injuries. Conclusion:Small knee flexion angle,large posterior GRF.and large knee valgus moment are risk factors of non-contact ACL injury determined by a stochastic biomechanical model with a cause-and-effect relationship.

  3. A novel finite element method based biomechanical model for HIT-robot assisted orthopedic surgery system.

    Science.gov (United States)

    Jia, Zhiheng; Du, Zhijiang; Wang, Monan

    2006-01-01

    To build a biomechanical human model can make much sense for surgical training and surgical rehearse. Especially, it will be more meaningful to develop a biomechanical model to guide the control strategy for the medical robots in HIT-Robot Assisted Orthopedic Surgery System (HIT-RAOS). In this paper, based the successful work of others, a novel reliable finite element method based biomechanical model for HIT-RAOS was developed to simulate the force needed in reposition procedure. Geometrical model was obtained from 3D reconstruction from CT images of a just died man. Using this boundary information, the finite element model of the leg including part of femur, broken upper tibia, broken lower tibia, talus, calcaneus, Kirschner nail, muscles and other soft tissues was created in ANSYS. Furthermore, as it was too difficult to reconstruct the accurate geometry model from CT images, a new simplified muscle model was presented. The bony structures and tendons were defined as linearly elastic, while soft tissues and muscle fibers were assumed to be hyper elastic. To validate this model, the same dead man was involved to simulate the patient, and a set of data of the force needed to separate the two broken bones and the distance between them in reposition procedure was recorded. Then, another set of data was acquired from the finite element analysis. After comparison, the two sets of data matched well. The Finite Element model was proved to be acceptable. PMID:17959437

  4. Occupational stress and biomechanical risk in a high fashion clothing company.

    Science.gov (United States)

    Forcella, Laura; Bonfiglioli, Roberta; Cutilli, Piero; Antonucci, Andrea; Di Donato, Angela; Siciliano, Eugenio; Cortini, Michela; Violante, Francesco Saverio; Boscolo, Paolo

    2012-01-01

    Psychosocial discomfort may amplify job-related risk factors. The aim of this study is to evaluate job stress in a high fashion clothing company with upper limb biomechanical overload due to repetitive and forceful manual activities. Biomechanical risk was analyzed and in part reduced using the OCRA Check list. A total of 518 workers (433 females and 85 males) were investigated to determine anxiety (by STAI 1 and 2), occupational stress (using the Italian version of the Karasek Job Content Questionnaire) and perception of symptoms. Final biomechanical assessment did not reveal high risk jobs, except for cutting. Although the perception of anxiety and job insecurity was within the normal range, all the workers showed a high level of job strain (correlated with the perception of symptoms) due, probably, to very low decision latitude. It was suggested that job strain may increase the perception of symptoms. Moreover, the result of this study indicates that musculoskeletal overload has to be further analyzed since its low level is not in agreement with the level of discomfort due to the repetitive tasks. PMID:22317171

  5. Carpal tunnel release: do we understand the biomechanical consequences?

    Science.gov (United States)

    Morrell, Nathan T; Harris, Andrew; Skjong, Christian; Akelman, Edward

    2014-11-01

    Carpal tunnel release is a very common procedure performed in the United States. While the procedure is often curative, some patients experience postoperative scar sensitivity, pillar pain, grip weakness, or recurrent median nerve symptoms. Release of the carpal tunnel has an effect on carpal anatomy and biomechanics, including increases in carpal arch width and carpal tunnel volume and changes in muscle and tendon mechanics. Our understanding of how these biomechanical changes contribute to postoperative symptoms is still evolving. We review the relevant morphometric and biomechanical changes that occur following release of the transverse carpal ligament. PMID:25364635

  6. Knowledge discovery in databases of biomechanical variables: application to the sit to stand motor task

    Directory of Open Access Journals (Sweden)

    Benvenuti Francesco

    2004-10-01

    Full Text Available Abstract Background The interpretation of data obtained in a movement analysis laboratory is a crucial issue in clinical contexts. Collection of such data in large databases might encourage the use of modern techniques of data mining to discover additional knowledge with automated methods. In order to maximise the size of the database, simple and low-cost experimental set-ups are preferable. The aim of this study was to extract knowledge inherent in the sit-to-stand task as performed by healthy adults, by searching relationships among measured and estimated biomechanical quantities. An automated method was applied to a large amount of data stored in a database. The sit-to-stand motor task was already shown to be adequate for determining the level of individual motor ability. Methods The technique of search for association rules was chosen to discover patterns as part of a Knowledge Discovery in Databases (KDD process applied to a sit-to-stand motor task observed with a simple experimental set-up and analysed by means of a minimum measured input model. Selected parameters and variables of a database containing data from 110 healthy adults, of both genders and of a large range of age, performing the task were considered in the analysis. Results A set of rules and definitions were found characterising the patterns shared by the investigated subjects. Time events of the task turned out to be highly interdependent at least in their average values, showing a high level of repeatability of the timing of the performance of the task. Conclusions The distinctive patterns of the sit-to-stand task found in this study, associated to those that could be found in similar studies focusing on subjects with pathologies, could be used as a reference for the functional evaluation of specific subjects performing the sit-to-stand motor task.

  7. Biomechanical ToolKit: Open-source framework to visualize and process biomechanical data.

    Science.gov (United States)

    Barre, Arnaud; Armand, Stéphane

    2014-04-01

    C3D file format is widely used in the biomechanical field by companies and laboratories to store motion capture systems data. However, few software packages can visualize and modify the integrality of the data in the C3D file. Our objective was to develop an open-source and multi-platform framework to read, write, modify and visualize data from any motion analysis systems using standard (C3D) and proprietary file formats (used by many companies producing motion capture systems). The Biomechanical ToolKit (BTK) was developed to provide cost-effective and efficient tools for the biomechanical community to easily deal with motion analysis data. A large panel of operations is available to read, modify and process data through C++ API, bindings for high-level languages (Matlab, Octave, and Python), and standalone application (Mokka). All these tools are open-source and cross-platform and run on all major operating systems (Windows, Linux, MacOS X). PMID:24548899

  8. Evaluation of a clinical needs assessment and exploration of the associated supports for students with a disability in clinical practice: part 2.

    Science.gov (United States)

    Howlin, Frances; Halligan, Phil; O'Toole, Sinead

    2014-09-01

    Engagement and successful completion of nursing and midwifery programmes may be predicated on the identification and implementation of reasonable accommodations to facilitate clinical learning for students with a disability. This qualitative study aims to evaluate a clinical needs assessment for students with a disability and explore their experiences of support in clinical practice. A purposive sample of year one undergraduate students was used. Four students consented to participate and undertook an individual interview. Their disabilities were categorised as specific learning disability (dyslexia) (n = 3) and mental health (n = 1). Data analysis revealed two main themes 'students' experiences of disclosure' and 'receiving support'. Findings revealed that all students disclosed on placement, however, the extent of disclosure was influenced by personal and environmental factors. Students used the clinical needs assessment to highlight accommodations to clinical staff on placement. Issues of concern that arose, included communication between all key stakeholders, negative staff attitudes and the need to improve the provision of accommodations. This preliminary evaluation indicates that the Clinical Needs Assessment bridges the gap in provision of student support between higher education and healthcare institutions. Findings suggest that competence based needs assessments can identify individualised reasonable accommodations for students undertaking clinical placements. PMID:25052770

  9. Biomechanical Analysis of T2 Exercise

    Science.gov (United States)

    DeWitt, John K.; Ploutz-Snyder, Lori; Everett, Meghan; Newby, Nathaniel; Scott-Pandorf, Melissa; Guilliams, Mark E.

    2010-01-01

    Crewmembers regularly perform treadmill exercise on the ISS. With the implementation of T2 on ISS, there is now the capacity to obtain ground reaction force (GRF) data GRF data combined with video motion data allows biomechanical analyses to occur that generate joint torque estimates from exercise conditions. Knowledge of how speed and load influence joint torque will provide quantitative information on which exercise prescriptions can be based. The objective is to determine the joint kinematics, ground reaction forces, and joint kinetics associated with treadmill exercise on the ISS. This study will: 1) Determine if specific exercise speed and harness load combinations are superior to others in exercise benefit; and 2) Aid in the design of exercise prescriptions that will be most beneficial in maintaining crewmember health.

  10. The biomechanics of vertical hopping: a review.

    Science.gov (United States)

    Lamontagne, Mario; Kennedy, Matthew J

    2013-01-01

    Repetitive vertical hopping is a simple and relatively controlled task useful for studying basic neuromuscular properties and tissue mechanics. However, several biomechanical and physiological factors are involved. This article provides an overview of muscle and tendon properties and how these interact during vertical hopping. Muscle properties discussed are force-velocity and force-length relationships, electromechanical delay, muscle fiber type, stretch induced contraction amplification, and muscle spindle afferent feedback. Tendon properties include storage and reuse of elastic energy, tendon stiffness, afferent information from Golgi tendon organs, and failure points. These muscle and tendon properties interact to generate vertical hopping force and power. In addition to these basic properties, there are other more complicated factors to consider when analyzing vertical hopping such as balance and coordination. A wealth of information can be gathered by studying vertical hopping. Caution should be taken, however, to prevent inappropriate conclusions being drawn about hop performance due to oversimplification. PMID:24067123

  11. Development of a biomechanical energy harvester

    Directory of Open Access Journals (Sweden)

    Donelan J Maxwell

    2009-06-01

    Full Text Available Abstract Background Biomechanical energy harvesting–generating electricity from people during daily activities–is a promising alternative to batteries for powering increasingly sophisticated portable devices. We recently developed a wearable knee-mounted energy harvesting device that generated electricity during human walking. In this methods-focused paper, we explain the physiological principles that guided our design process and present a detailed description of our device design with an emphasis on new analyses. Methods Effectively harvesting energy from walking requires a small lightweight device that efficiently converts intermittent, bi-directional, low speed and high torque mechanical power to electricity, and selectively engages power generation to assist muscles in performing negative mechanical work. To achieve this, our device used a one-way clutch to transmit only knee extension motions, a spur gear transmission to amplify the angular speed, a brushless DC rotary magnetic generator to convert the mechanical power into electrical power, a control system to determine when to open and close the power generation circuit based on measurements of knee angle, and a customized orthopaedic knee brace to distribute the device reaction torque over a large leg surface area. Results The device selectively engaged power generation towards the end of swing extension, assisting knee flexor muscles by producing substantial flexion torque (6.4 Nm, and efficiently converted the input mechanical power into electricity (54.6%. Consequently, six subjects walking at 1.5 m/s generated 4.8 ± 0.8 W of electrical power with only a 5.0 ± 21 W increase in metabolic cost. Conclusion Biomechanical energy harvesting is capable of generating substantial amounts of electrical power from walking with little additional user effort making future versions of this technology particularly promising for charging portable medical devices.

  12. Laryngeal biomechanics of the singing voice.

    Science.gov (United States)

    Koufman, J A; Radomski, T A; Joharji, G M; Russell, G B; Pillsbury, D C

    1996-12-01

    By transnasal fiberoptic laryngoscopy, patients with functional voice often demonstrate abnormal laryngeal biomechanics, commonly supraglottic contraction. Appropriately, such conditions are sometimes termed muscle tension dysphonias. Singers working at the limits of their voice may also transiently demonstrate comparable tension patterns. However, the biomechanics of normal singing, particularly for different singing styles, have not been previously well characterized. We used transnasal fiberoptic laryngoscopy to study 100 healthy singers to assess patterns of laryngeal tension during normal singing and to determine whether factors such as sex, occupation, and style of singing influence laryngeal muscle tension. Thirty-nine male and 61 female singers were studied; 48 were professional singers, and 52 were amateurs. Examinations of study subjects performing standardized and nonstandardized singing tasks were recorded on a laser disk and subsequently analyzed in a frame-by-frame fashion by a blinded otolaryngologist. Each vocal task was graded for muscle tension by previously established criteria, and objective muscle tension scores were computed. The muscle tension score was expressed as a percentage of frames for each task with one of the laryngeal muscle tension patterns shown. The lowest muscle tension scores were seen in female professional singers, and the highest muscle tension scores were seen in amateur female singers. Male singers (professional and amateur) had intermediate muscle tension scores. Classical singers had lower muscle tension scores than nonclassical singers, with the lowest muscle tension scores being seen in those singing choral music (41%), art song (47%), and opera (57%), and the highest being seen in those singing jazz/pop (65%), musical theater (74%), bluegrass/country and western (86%), and rock/gospel (94%). Analyzed also were the influences of vocal nodules, prior vocal training, number of performance and practice hours per week

  13. Biomechanical research in dance: a literature review.

    Science.gov (United States)

    Krasnow, Donna; Wilmerding, M Virginia; Stecyk, Shane; Wyon, Matthew; Koutedakis, Yiannis

    2011-03-01

    The authors reviewed the literature, published from 1970 through December 2009, on biomechanical research in dance. To identify articles, the authors used search engines, including PubMed and Web of Science, five previous review articles, the Dance Medicine and Science Bibliography, and reference lists of theses, dissertations, and articles being reviewed. Any dance research articles (English language) involving the use of electromyography, forceplates, motion analysis using photography, cinematography or videography, and/or physics analysis were included. A total of 89 papers, theses/dissertations, and abstracts were identified and reviewed, grouped by the movement concept or specialized movements being studied: alignment (n = 8), plié (8), relevé (8), passé (3), degagé (3), développé (7), rond de jambe (3), grand battement (4), arm movements (1), forward stepping (3), turns (6), elevation work (28), falls (1), and dance-specific motor strategies (6). Several recurring themes emerged from these studies: that elite dancers demonstrate different and superior motor strategies than novices or nondancers; that dancers perform differently when using a barre as opposed to without a barre, both in terms of muscle activation patterns and weight shift strategies; that while skilled dancers tend to be more consistent across multiple trials of a task, considerable variability is seen among participants, even when matched for background, years of training, body type, and other variables; and that dance teachers recommend methods of achieving movement skills that are inconsistent with optimal biomechanical function, as well as inconsistent with strategies employed by elite dancers. Measurement tools and the efficacy of study methodologies are also discussed. PMID:21442132

  14. Entendendo o conceito PIRO: da teoria à prática clínica - parte 2 Understanding the PIRO concept: from theory to clinical practice - part 2

    Directory of Open Access Journals (Sweden)

    Maira de Moraes Rosolem

    2010-03-01

    Full Text Available Um sistema de estadiamento da sepse com foco na predisposição, no insulto, na resposta do hospedeiro e na falência orgânica pode fornecer uma base útil para a estratificação do risco. O conhecimento das interações entre os fatores predisponentes, características do insulto e resposta do hospedeiro pode nos ajudar a melhorar a compreensão sobre a fisiopatologia da sepse e permitir uma abordagem terapêutica mais individualizada. Estudos clínicos recentes documentaram a relevância da abordagem PIRO na estratificação da gravidade de pacientes sépticos na unidade de terapia intensiva, e também para condições específicas como pneumonia adquirida na comunidade e pneumonia associada a ventilação mecânica, com bom desempenho para previsão do desfecho. Nesta revisão, descrevemos como este novo conceito pode ser utilizado na prática clínica e fornecemos algumas compreensões sobre a sua utilidade para facilitar a estratificação e potencial para inclusão em estudos clínicos de tratamentos da sepse.A sepsis staging system focused on predisposition, insult, host response and organ failure may provide a useful basis for risk stratification. Knowledge on interactions among predisposing factors, insult characteristics and host response might help us to improve our understanding on sepsis pathophysiology and allow more individual therapeutic approach. Recent clinical studies documented the clinical importance of PIRO approach for severity stratification in septic patients in intensive care unit, and also for specific conditions such as community acquired pneumonia and ventilator associated pneumonia , with a good performance for outcome prediction. In this review we describe how this new concept can be used in clinical practice and provide some insights on its usefulness to facilitate the stratification and potential for enrollment in clinical trials of sepsis therapies.

  15. Distension of the renal pelvis in kidney stone patients: sensory and biomechanical responses

    DEFF Research Database (Denmark)

    Pedersen, Katja Venborg; Liao, Donghua; Osther, Susanne Sloth;

    2012-01-01

    The pathogenesis of symptoms in urolithiasis is poorly understood. Traditionally increased endoluminal pressure is considered the main mechanism causing pain in the upper urinary tract but clinical data are sparse. The aim of the present study was to develop a new model related to mechanosensation...... was a relation between pressure and pain score, the non-homogenous spatial strain distribution suggests that the 3D biomechanical properties of the renal pelvis are not reflected by simple estimates of tension based on pressure and volume....

  16. Sensory and biomechanical responses to distension of the renal pelvis in kidney stone patients

    DEFF Research Database (Denmark)

    Pedersen, Katja Venborg; Liao, Donghua; Osther, Susanne Sloth;

    The pathogenesis of symptoms in urolithiasis is poorly understood. Traditionally increased endoluminal pressure is considered the main mechanism causing pain in the upper urinary tract but clinical data are sparse. The aim of the present study was to develop a new model related to mechanosensation...... was a relation between pressure and pain score, the non-homogenous spatial strain distribution suggests that the 3D biomechanical properties of the renal pelvis are not reflected by simple estimates of tension based on pressure and volume....

  17. Measurement scales in clinical research of the upper extremity, part 1: general principles, measures of general health, pain, and patient satisfaction.

    Science.gov (United States)

    Badalamente, Marie; Coffelt, Laureen; Elfar, John; Gaston, Glenn; Hammert, Warren; Huang, Jerry; Lattanza, Lisa; Macdermid, Joy; Merrell, Greg; Netscher, David; Panthaki, Zubin; Rafijah, Greg; Trczinski, Douglas; Graham, Brent

    2013-02-01

    Measurement is a fundamental cornerstone in all aspects of scientific discovery, including clinical research. To be useful, measurement instruments must meet several key criteria, the most important of which are satisfactory reliability, validity, and responsiveness. Part 1 of this article reviews the general concepts of measurement instruments and describes the measurement of general health, pain, and patient satisfaction. PMID:23351912

  18. Levels of antibody to conserved parts of Plasmodium falciparum merozoite surface protein 1 in Ghanaian children are not associated with protection from clinical malaria

    DEFF Research Database (Denmark)

    Dodoo, D; Theander, T G; Kurtzhals, J A;

    1999-01-01

    The 19-kDa conserved C-terminal part of the Plasmodium falciparum merozoite surface protein 1 (PfMSP119) is a malaria vaccine candidate antigen, and human antibody responses to PfMSP119 have been associated with protection against clinical malaria. In this longitudinal study carried out in an are...

  19. The search for performance related factors in biomechanics

    OpenAIRE

    Richter, Chris

    2014-01-01

    Introduction: The identification of performance related factors (PRFs) is a major goal in sports biomechanics. However, PRFs identified across studies are inconsistent and this might be explained by the limitations of discrete point analysis, which is commonly used. New data analysis techniques involving continuous waveform analysis (e.g. functional principal component analysis, fPCA) have been suggested, but their use in biomechanics is not widespread, and they also have limitations. Anot...

  20. Carpal Tunnel Release: Do We Understand the Biomechanical Consequences?

    OpenAIRE

    Morrell, Nathan T.; Harris, Andrew; Skjong, Christian; Akelman, Edward

    2014-01-01

    Carpal tunnel release is a very common procedure performed in the United States. While the procedure is often curative, some patients experience postoperative scar sensitivity, pillar pain, grip weakness, or recurrent median nerve symptoms. Release of the carpal tunnel has an effect on carpal anatomy and biomechanics, including increases in carpal arch width and carpal tunnel volume and changes in muscle and tendon mechanics. Our understanding of how these biomechanical changes contribute to ...

  1. BIOMECHANICAL PRINCIPLES PHYSICAL REHABILITATION OF CHILDREN WITH CEREBRAL PALSY

    OpenAIRE

    S. D. Korshunov; K. V. Davletyarova; L. V. Kapilevich

    2016-01-01

    Aim. We studied the basic biomechanical principles of physical rehabilitation of children with cerebral palsy.Materials and methods. Methods of Motion Tracking and electromyography investigated the biomechanical characteristics of gait in children with cerebral palsy. It is shown that the main differences between dynamic stereotype walk pediatric patients is to delay moving forward center of gravity and the disorganization of the lower limb movements (especially knee) in the vertical plane. P...

  2. Biomechanics and Cycling BIOMECÁNICA Y CICLISMO

    OpenAIRE

    M. Gutierrez

    2010-01-01

    The aim of this essay is giving a general overview about sport cycling from a biomechanical perspective. Although it is necessary to say that the extraordinary dimension of the huge scientific production related to the topic makes difficult to deal this area in just one essay. Due to the variety of contents included into cycling biomechanics, contents in this essay have been restricted into three units: the first, focusing the study of forces opposed to displacement, and specially to the anal...

  3. Single Cell Biomechanical Phenotyping using Microfluidics and Nanotechnology

    OpenAIRE

    Babahosseini, Hesam

    2016-01-01

    Cancer progression is accompanied with alterations in the cell biomechanical phenotype, including changes in cell structure, morphology, and responses to microenvironmental stress. These alterations result in an increased deformability of transformed cells and reduced resistance to mechanical stimuli, enabling motility and invasion. Therefore, single cell biomechanical properties could be served as a powerful label-free biomarker for effective characterization and early detection of single ca...

  4. Biomechanics and control of vocalization in a non-songbird

    OpenAIRE

    Elemans, Coen P.H; Zaccarelli, Riccardo; Herzel, Hanspeter

    2007-01-01

    The neuromuscular control of vocalization in birds requires complicated and precisely coordinated motor control of the vocal organ (i.e. the syrinx), the respiratory system and upper vocal tract. The biomechanics of the syrinx is very complex and not well understood. In this paper, we aim to unravel the contribution of different control parameters in the coo of the ring dove (Streptopelia risoria) at the syrinx level. We designed and implemented a quantitative biomechanical syrinx model that ...

  5. Jet Methods in Time-Dependent Lagrangian Biomechanics

    OpenAIRE

    Ivancevic, Tijana T.

    2009-01-01

    In this paper we propose the time-dependent generalization of an `ordinary' autonomous human biomechanics, in which total mechanical + biochemical energy is not conserved. We introduce a general framework for time-dependent biomechanics in terms of jet manifolds associated to the extended musculo-skeletal configuration manifold, called the configuration bundle. We start with an ordinary configuration manifold of human body motion, given as a set of its all active degrees of freedom (DOF) for ...

  6. Proposed changes in personality and personality disorder assessment and diagnosis for DSM-5 part II: clinical application

    NARCIS (Netherlands)

    A.E. Skodol; D.S. Bender; J.M. Oldham; L.A. Clark; L.C. Morey; R. Verheul; R.F. Krueger; L.J. Siever

    2011-01-01

    The four-part assessment of personality psychopathology proposed for DSM-5 focuses attention on identifying personality psychopathology with increasing degrees of specificity, based on a clinician's available time, information, and expertise. In Part I of this two-part article, we described the comp

  7. Biomechanics of Artificial Disc Replacements Adjacent to a 2-Level Fusion in 4-Level Hybrid Constructs: An In Vitro Investigation

    OpenAIRE

    Liao, Zhenhua; Fogel, Guy R.; Wei, Na; Gu, Hongsheng; Liu, Weiqiang

    2015-01-01

    Background The ideal procedure for multilevel cervical degenerative disc diseases remains controversial. Recent studies on hybrid surgery combining anterior cervical discectomy and fusion (ACDF) and artificial cervical disc replacement (ACDR) for 2-level and 3-level constructs have been reported in the literature. The purpose of this study was to estimate the biomechanics of 3 kinds of 4-level hybrid constructs, which are more likely to be used clinically compared to 4-level arthrodesis. Mate...

  8. In vitro biomechanical study of pedicle screw pull-out strength based on different screw path preparation techniques

    OpenAIRE

    Mark Moldavsky; Kanaan Salloum; Brandon Bucklen; Saif Khalil; Jwalant S Mehta

    2016-01-01

    Background: Poor screw-to-bone fixation is a clinical problem that can lead to screw loosening. Under-tapping (UT) the pedicle screw has been evaluated biomechanically in the past. The objective of the study was to determine if pedicle preparation with a sequential tapping technique will alter the screw-to-bone fixation strength using a stress relaxation testing loading protocol. Materials and Methods: Three thoracolumbar calf spines were instrumented with pedicle screws that were either p...

  9. Construction and Biomechanical Properties of PolyAxial Self-Locking Anatomical Plate Based on the Geometry of Distal Tibia

    OpenAIRE

    Weiguo Liang; Weixiong Ye; Dongping Ye; Ziqiang Zhou; Zhiguang Chen; Aiguo Li; Zong-Han Xie; Lihai Zhang; Jiake Xu

    2014-01-01

    In order to provide scientific and empirical evidence for the clinical application of the polyaxial self-locking anatomical plate, 80 human tibias from healthy adults were scanned by spiral CT and their three-dimensional images were reconstructed using the surface shaded display (SSD) method. Firstly, based on the geometric data of distal tibia, a polyaxial self-locking anatomical plate for distal tibia was designed and constructed. Biomechanical tests were then performed by applying axial lo...

  10. Fibrin Sealant: A Review of the History, Biomechanics, and Current Applications for Prosthetic Fixation in Hernia Repair.

    Science.gov (United States)

    Watson, Jefferson Tyler; Webb, David L; Stoikes, Nathaniel F N; Voeller, Guy R

    2015-11-01

    The role of surgical adhesives in hernia repair has continued to evolve. The purpose of this chapter is to review the role of fibrin sealant and its application in general surgery for mesh fixation, specifically the history, biomechanics, and clinical utilization. The utilization of fibrin sealant for repair of groin hernias, both open and laparoscopic, ventral hernias, and hiatal hernias will be discussed. PMID:26696538

  11. Biomechanics and biomimetics in insect-inspired flight systems.

    Science.gov (United States)

    Liu, Hao; Ravi, Sridhar; Kolomenskiy, Dmitry; Tanaka, Hiroto

    2016-09-26

    Insect- and bird-size drones-micro air vehicles (MAV) that can perform autonomous flight in natural and man-made environments are now an active and well-integrated research area. MAVs normally operate at a low speed in a Reynolds number regime of 10(4)-10(5) or lower, in which most flying animals of insects, birds and bats fly, and encounter unconventional challenges in generating sufficient aerodynamic forces to stay airborne and in controlling flight autonomy to achieve complex manoeuvres. Flying insects that power and control flight by flapping wings are capable of sophisticated aerodynamic force production and precise, agile manoeuvring, through an integrated system consisting of wings to generate aerodynamic force, muscles to move the wings and a control system to modulate power output from the muscles. In this article, we give a selective review on the state of the art of biomechanics in bioinspired flight systems in terms of flapping and flexible wing aerodynamics, flight dynamics and stability, passive and active mechanisms in stabilization and control, as well as flapping flight in unsteady environments. We further highlight recent advances in biomimetics of flapping-wing MAVs with a specific focus on insect-inspired wing design and fabrication, as well as sensing systems.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. PMID:27528780

  12. ARTIFICIAL INTELLIGENCE IN SPORTS BIOMECHANICS: NEW DAWN OR FALSE HOPE?

    Directory of Open Access Journals (Sweden)

    Roger Bartlett

    2006-12-01

    Full Text Available This article reviews developments in the use of Artificial Intelligence (AI in sports biomechanics over the last decade. It outlines possible uses of Expert Systems as diagnostic tools for evaluating faults in sports movements ('techniques' and presents some example knowledge rules for such an expert system. It then compares the analysis of sports techniques, in which Expert Systems have found little place to date, with gait analysis, in which they are routinely used. Consideration is then given to the use of Artificial Neural Networks (ANNs in sports biomechanics, focusing on Kohonen self-organizing maps, which have been the most widely used in technique analysis, and multi-layer networks, which have been far more widely used in biomechanics in general. Examples of the use of ANNs in sports biomechanics are presented for javelin and discus throwing, shot putting and football kicking. I also present an example of the use of Evolutionary Computation in movement optimization in the soccer throw in, which predicted an optimal technique close to that in the coaching literature. After briefly overviewing the use of AI in both sports science and biomechanics in general, the article concludes with some speculations about future uses of AI in sports biomechanics.

  13. Developing more positive attitudes towards mental health nursing in undergraduate students: part 2--The impact of theory and clinical experience.

    Science.gov (United States)

    Happell, B; Robins, A; Gough, K

    2008-09-01

    Previous research examining the impact of education on nursing students' attitudes towards mental health nursing as a career has highlighted clinical experience as the primary influencing factor and generally has not considered the impact of theory. The current study compared a cohort of second-year and a cohort of third-year nursing students from the same university. Second-year students had received more theory and clinical experience than their counterparts. Questionnaires were distributed to the total population of students before commencement of, and after completion of clinical placement. This paper examines students' perceived preparedness for and satisfaction with clinical experience, attitudes towards people with mental illness, and attitudes towards mental health nursing as a career option following the completion of differing amounts of theory and clinical experience. The results demonstrate some statistically significant differences with increased amounts of theory and clinical experience in the second-year cohort being positively influential. The findings suggest that an increased component of theoretical and clinical experience in psychiatric/mental health nursing is likely to produce more positive attitudes towards people with mental illness and psychiatric/mental health nursing. However, little difference in perceived preparedness for and satisfaction with clinical experience was noted between the two cohorts. PMID:18768004

  14. Prostatic Artery Embolization (PAE) for Symptomatic Benign Prostatic Hyperplasia (BPH): Part 1, Pathological Background and Clinical Implications

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Fei, E-mail: feisun@ccmijesususon.com; Crisóstomo, Verónica, E-mail: crisosto@ccmijesususon.com; Báez-Díaz, Claudia, E-mail: cbaez@ccmijesususon.com; Sánchez, Francisco M., E-mail: msanchez@ccmijesususon.com [Jesús Usón Minimally Invasive Surgery Centre (Spain)

    2016-01-15

    Pathological features of benign prostatic hyperplasia (BPH) dictate various responses to prostatic artery embolization (PAE). Typically, BPH originates in the transition zone and periurethral region, where should be considered the primary target area in PAE procedures. Given that histological heterogeneity of components in hyperplasia nodules, epithelial or stromal, identifying the more responsive nodules to PAE will have clinical implications. Since some lower urinary tract symptoms (LUTS) in patients with BPH are usually related to bladder outlet obstruction-induced changes in bladder function rather than to outflow obstruction directly, proper selection of candidate patients prior to PAE is of great clinical importance. BPH is a typical chronic progressive condition, suggesting PAE could aim not only to relieve LUTS but also to delay or prevent the clinical progression. Awareness of the pathological background of BPH is essential for interventional radiologists to improve clinical outcomes and develop new treatment strategies in clinical practice of PAE.

  15. Prostatic Artery Embolization (PAE) for Symptomatic Benign Prostatic Hyperplasia (BPH): Part 1, Pathological Background and Clinical Implications

    International Nuclear Information System (INIS)

    Pathological features of benign prostatic hyperplasia (BPH) dictate various responses to prostatic artery embolization (PAE). Typically, BPH originates in the transition zone and periurethral region, where should be considered the primary target area in PAE procedures. Given that histological heterogeneity of components in hyperplasia nodules, epithelial or stromal, identifying the more responsive nodules to PAE will have clinical implications. Since some lower urinary tract symptoms (LUTS) in patients with BPH are usually related to bladder outlet obstruction-induced changes in bladder function rather than to outflow obstruction directly, proper selection of candidate patients prior to PAE is of great clinical importance. BPH is a typical chronic progressive condition, suggesting PAE could aim not only to relieve LUTS but also to delay or prevent the clinical progression. Awareness of the pathological background of BPH is essential for interventional radiologists to improve clinical outcomes and develop new treatment strategies in clinical practice of PAE

  16. Brain injury biomechanics in closed-head impact : Studies on injury epidemiology, tolerance criteria, biomechanics and traffic injury prevention

    OpenAIRE

    Viano, David

    1997-01-01

    Permanent disability from traumatic brain injury is a devastating consequence of traffic crashes. Injury prevention is a fruitful approach to reduce the incidence and severity of disabling brain injury. However, the development of effective prevention techniques requires better knowledge on the mechanisms and biomechanics of brain injury in closed-head impact. The overall aim of this study is focused on brain injury mechanisms, biomechanics, and tolerances in closed-head ...

  17. Biomechanical metrics of aesthetic perception in dance.

    Science.gov (United States)

    Bronner, Shaw; Shippen, James

    2015-12-01

    The brain may be tuned to evaluate aesthetic perception through perceptual chunking when we observe the grace of the dancer. We modelled biomechanical metrics to explain biological determinants of aesthetic perception in dance. Eighteen expert (EXP) and intermediate (INT) dancers performed développé arabesque in three conditions: (1) slow tempo, (2) slow tempo with relevé, and (3) fast tempo. To compare biomechanical metrics of kinematic data, we calculated intra-excursion variability, principal component analysis (PCA), and dimensionless jerk for the gesture limb. Observers, all trained dancers, viewed motion capture stick figures of the trials and ranked each for aesthetic (1) proficiency and (2) movement smoothness. Statistical analyses included group by condition repeated-measures ANOVA for metric data; Mann-Whitney U rank and Friedman's rank tests for nonparametric rank data; Spearman's rho correlations to compare aesthetic rankings and metrics; and linear regression to examine which metric best quantified observers' aesthetic rankings, p < 0.05. The goodness of fit of the proposed models was determined using Akaike information criteria. Aesthetic proficiency and smoothness rankings of the dance movements revealed differences between groups and condition, p < 0.0001. EXP dancers were rated more aesthetically proficient than INT dancers. The slow and fast conditions were judged more aesthetically proficient than slow with relevé (p < 0.0001). Of the metrics, PCA best captured the differences due to group and condition. PCA also provided the most parsimonious model to explain aesthetic proficiency and smoothness rankings. By permitting organization of large data sets into simpler groupings, PCA may mirror the phenomenon of chunking in which the brain combines sensory motor elements into integrated units of behaviour. In this representation, the chunk of information which is remembered, and to which the observer reacts, is the elemental mode shape of

  18. Biomechanics of the anterior cruciate ligament: Physiology, rupture and reconstruction techniques.

    Science.gov (United States)

    Domnick, Christoph; Raschke, Michael J; Herbort, Mirco

    2016-02-18

    The influences and mechanisms of the physiology, rupture and reconstruction of the anterior cruciate ligament (ACL) on kinematics and clinical outcomes have been investigated in many biomechanical and clinical studies over the last several decades. The knee is a complex joint with shifting contact points, pressures and axes that are affected when a ligament is injured. The ACL, as one of the intra-articular ligaments, has a strong influence on the resulting kinematics. Often, other meniscal or ligamentous injuries accompany ACL ruptures and further deteriorate the resulting kinematics and clinical outcomes. Knowing the surgical options, anatomic relations and current evidence to restore ACL function and considering the influence of concomitant injuries on resulting kinematics to restore full function can together help to achieve an optimal outcome. PMID:26925379

  19. Avaliação biomecânica das fraturas intra-articulares do calcâneo e sua correlação clínica radiográfica Biomechanical evaluation of intra articular calcaneal fracture and clinical radiographic correlation

    Directory of Open Access Journals (Sweden)

    Marcos Emilio Kuschnaroff Contreras

    2004-06-01

    Full Text Available O presente estudo teve o objetivo de oferecer uma avaliação clínica, radiográfica e biomecânica de pacientes com fratura intraarticular de calcâneo, submetidos à redução aberta e fixação interna. A amostra consistiu em 22 pacientes, 20 do sexo masculino e dois do sexo feminino, com idade média de 40,95 (± 11,63 anos. Os autores realizaram avaliações radiográficas do ângulo de Böhler e Gissane, no pré e no pós-operatório, além de utilizarem a tomografia computadorizada para avaliação da classificação de Sanders. A avaliação da Distribuição da Pressão Plantar foi realizada pelo sistema F-scan. Os resultados clínicos encontrados foram satisfatórios apresentando, pontuação média de 75,5 no critério da AOFAS.. A redução cirúrgica resultou em uma melhora dos ângulos de Böhler e Gissane. O estudo mostrou diferenças estatisticamente significantes entre o antepé o retropé fraturados no que tange sobre a área de contato, pressão e força de reação do solo. Os valores encontrados para estes parâmetros foram maiores no retropé que no antepé fraturados. A trajetória de Pressão (COP foi menor no pé fraturado que no pé normal. Encontrou-se correlação entre o Ângulo de Gissane após a redução e o Segundo Pico de Força, indicando que quanto melhor a redução deste ângulo , melhor a impulsão. Também encontrou-se a correlação entre a pontuação AOFAS e o Primeiro Pico de Força, mostrando que quanto melhor o resultado clínico melhor o apoio do retropé.The present study had an objective to perfom a clinical, radiographic and biomechanical evaluation in patients with calcaneal fractures submitted to open reduction with internal fixation. The sample consisted of 22 patients - 20 male and 2 female with an average age of 40,95 (±11,63 years old. The authors have done radiographic evaluation of the pre and post operatory of Böchler and Gissane angles; furthermore, they used a CT scanning for Sander

  20. Comparative biomechanics: life's physical world (second edition)

    CERN Document Server

    Vogel, Steven

    2013-01-01

    Why do you switch from walking to running at a specific speed? Why do tall trees rarely blow over in high winds? And why does a spore ejected into air at seventy miles per hour travel only a fraction of an inch? Comparative Biomechanics is the first and only textbook that takes a comprehensive look at the mechanical aspects of life--covering animals and plants, structure and movement, and solids and fluids. An ideal entry point into the ways living creatures interact with their immediate physical world, this revised and updated edition examines how the forms and activities of animals and plants reflect the materials available to nature, considers rules for fluid flow and structural design, and explores how organisms contend with environmental forces. Drawing on physics and mechanical engineering, Steven Vogel looks at how animals swim and fly, modes of terrestrial locomotion, organism responses to winds and water currents, circulatory and suspension-feeding systems, and the relationship between size and mech...

  1. SERVICE IN BADMINTON: A BIOMECHANICAL STUDY

    Directory of Open Access Journals (Sweden)

    Saleem Ahmed

    2015-03-01

    Full Text Available To find out the differences between forehand and backhand short services in badminton, the present study was designed to analyze the biomechanical variables and segmental angles - shuttle velocity, wrist angle, elbow angle and shoulder angle of six male badminton players. The data were recorded during “North-Zone Intervarsity Championship” held at Aligarh Muslim University, Aligarh, India. All subjects in the study were right handed badminton players. The mean age, body height and body weight were reported as 18.33 years (±1.71, 166.5cm (±3.30 and 57.17kg (±7.93 respectively. The movements were recorded by ‘Canon Legria HF S10 Comcorder’ operating at 60 Hz. The identified clips were analyzed with the help of ‘Silicon Coach Pro 7’ motion analysis software. The result revealed that there was significant difference found between forehand and backhand short service in respect to shoulder angle at 0.05 level of significance.

  2. Functional anatomy and biomechanics of the carpus

    International Nuclear Information System (INIS)

    The wrist is an exceedingly complex structure composed of several joints and a dedicated ligamentous system. Its functional principles allow a wide range of carpal motion and make the wrist remarkably resistant to external stress forces: The proximal carpal row serves as an intercalated link interposed between the static elements of both the forearm and the distal carpal row. Like a flexible placeholder, the proximal row synchronously adapts to the spatial and temporal requirements of the wrist. There are synergistic movement patterns including simultaneous flexion of the proximal row as the wrist is deviated radially and simultaneous extension during ulnar deviation. Together with pronosupination of the radioulnar joints, the combined radial/ulnar inclination and flexion/extension enable spherical, out-of-plane movements of the hand. Carpal function is best explained by the ''model of a ring under tension.'' This review addresses the anatomy and the biomechanics of the wrist and illustrates systematic image analysis by using carpal lines and angles as well as indices of carpal height. (orig.)

  3. The biomechanics of throwing: simplified and cogent.

    Science.gov (United States)

    Weber, Alexander E; Kontaxis, Andreas; O'Brien, Stephen J; Bedi, Asheesh

    2014-06-01

    The majority of shoulder injuries occur due to repetitive overhead movements, with baseball pitching being the most common mechanism for overuse injury. Before studying the treatment of these shoulder injuries, it is paramount that the health professional have an understanding of the etiology of and the underlying mechanisms for shoulder pathology. The act of overhead throwing is an eloquent full-body motion that requires tremendous coordination from the time of force generation to follow-through. The shoulder complex is a crucial component of the upper body kinetic chain as it transmits force created in the lower body to the arm and hand to produce velocity and accuracy with ball release. The focus of this article is on the biomechanics of the throwing motion, with emphasis on the kinematics of the shoulder. The established phases of the throwing motion will be reviewed in a stepwise manner and the contributions of osseous and soft-tissue structures to the successful completion of each phase will be discussed. PMID:24787720

  4. Computational biomechanics of bone's responses to dental prostheses - osseointegration, remodeling and resorption

    International Nuclear Information System (INIS)

    Clinical and experimental studies showed that human bone has the ability to remodel itself to better adapt to its biomechanical environment by changing both its material properties and geometry. As a consequence of the rapid development and extensive applications of major dental restorations such as implantation and fixed partial denture (FPD), the effect of bone remodeling on the success of a dental restorative surgery is becoming critical for prosthetic design and pre-surgical assessment. This paper aims to provide a computational biomechanics framework to address dental bone's responses as a result of dental restoration. It explored three important issues of resorption, apposition and osseointegration in terms of remodeling simulation. The published remodeling data in long bones were regulated to drive the computational remodeling prediction for the dental bones by correlating the results to clinical data. It is anticipated that the study will provide a more predictive model of dental bone response and help develop a new design methodology for patient-specific dental prosthetic restoration.

  5. Dynamic ultra high speed Scheimpflug imaging for assessing corneal biomechanical properties

    Directory of Open Access Journals (Sweden)

    Renato Ambrósio Jr

    2013-04-01

    Full Text Available OBJECTIVE: To describe a novel technique for clinical characterization of corneal biomechanics using non-invasive dynamic imaging. METHODS: Corneal deformation response during non contact tonometry (NCT is monitored by ultra-high-speed (UHS photography. The Oculus Corvis ST (Scheimpflug Technology; Wetzlar, Germany has a UHS Scheimpflug camera, taking over 4,300 frames per second and of a single 8mm horizontal slit, for monitoring corneal deformation response to NCT. The metered collimated air pulse or puff has a symmetrical configuration and fixed maximal internal pump pressure of 25 kPa. The bidirectional movement of the cornea in response to the air puff is monitored. RESULTS: Measurement time is 30ms, with 140 frames acquired. Advanced algorithms for edge detection of the front and back corneal contours are applied for every frame. IOP is calculated based on the first applanation moment. Deformation amplitude (DA is determined as the highest displacement of the apex in the highest concavity (HC moment. Applanation length (AL and corneal velocity (CVel are recorded during ingoing and outgoing phases. CONCLUSION: Corneal deformation can be monitored during non contact tonometry. The parameters generated provide clinical in vivo characterization of corneal biomechanical properties in two dimensions, which is relevant for different applications in Ophthalmology.

  6. Tumor growth prediction with reaction-diffusion and hyperelastic biomechanical model by physiological data fusion.

    Science.gov (United States)

    Wong, Ken C L; Summers, Ronald M; Kebebew, Electron; Yao, Jianhua

    2015-10-01

    The goal of tumor growth prediction is to model the tumor growth process, which can be achieved by physiological modeling and model personalization from clinical measurements. Although image-driven frameworks have been proposed with promising results, several issues such as infinitesimal strain assumptions, complicated personalization procedures, and the lack of functional information, may limit their prediction accuracy. In view of these issues, we propose a framework for pancreatic neuroendocrine tumor growth prediction, which comprises a FEM-based tumor growth model with coupled reaction-diffusion equation and nonlinear biomechanics. Physiological data fusion of structural and functional images is used to improve the subject-specificity of model personalization, and a derivative-free global optimization algorithm is adopted to facilitate the complicated model and accommodate flexible choices of objective functions. With this flexibility, we propose an objective function accounting for both the tumor volume difference and the root-mean-squared error of intracellular volume fractions. Experiments were performed on synthetic and clinical data to verify the parameter estimation capability and the prediction performance. Comparisons of using different biomechanical models and objective functions were also performed. From the experimental results of eight patient data sets, the average recall, precision, Dice coefficient, and relative volume difference between predicted and measured tumor volumes were 84.5 ± 6.9%, 85.8 ± 8.2%, 84.6 ± 1.7%, and 14.2 ± 8.4%, respectively. PMID:25962846

  7. A biomechanical comparison of four different fixation methods for midshaft clavicle fractures.

    Science.gov (United States)

    Chen, Yang; Yang, Yang; Ma, Xinlong; Xu, Weiguo; Ma, Jianxiong; Zhu, Shaowen; Ma, Baoyi; Xing, Dan

    2016-01-01

    Clavicle fractures may occur in all age groups, and 70%-80% of clavicle fractures occur in the midshaft. Many methods for treating midshaft clavicular fractures have been reported and remain controversial. To provide some guidance for clinical treatment, 30 artificial polymethyl methacrylate models of the clavicle were sewn obliquely at the midshaft to simulate the most common type of clavicular fractures, and the fracture models were divided into five groups randomly and were fixed as follows: the reconstruction plates were placed at the superior position of the fracture model (R-S group), the reconstruction plates were placed at the anteroinferior position of the fracture model (R-AI group), the locking plates were placed at the superior position (L-S group), the locking plates were placed at the anteroinferior position (L-AI group); and the control models were unfixed (control group). The strain gauges were attached to the bone surface near the fracture fragments, and then, the biomechanical properties of the specimens were measured using the compression test, torsion test and three-point bending test. The results showed that plate fixation can provide a stable construct to help with fracture healing and is the preferred method in the treatment of clavicle fractures. The locking plate provides the best biomechanical stability when placed at the anteroinferior position, and this surgical method can reduce the operation time and postoperative complications; thus, it would be a better choice in clinical practice. PMID:26586526

  8. Computational biomechanics of bone's responses to dental prostheses - osseointegration, remodeling and resorption

    Science.gov (United States)

    Li, Wei; Rungsiyakull, Chaiy; Field, Clarice; Lin, Daniel; Zhang, Leo; Li, Qing; Swain, Michael

    2010-06-01

    Clinical and experimental studies showed that human bone has the ability to remodel itself to better adapt to its biomechanical environment by changing both its material properties and geometry. As a consequence of the rapid development and extensive applications of major dental restorations such as implantation and fixed partial denture (FPD), the effect of bone remodeling on the success of a dental restorative surgery is becoming critical for prosthetic design and pre-surgical assessment. This paper aims to provide a computational biomechanics framework to address dental bone's responses as a result of dental restoration. It explored three important issues of resorption, apposition and osseointegration in terms of remodeling simulation. The published remodeling data in long bones were regulated to drive the computational remodeling prediction for the dental bones by correlating the results to clinical data. It is anticipated that the study will provide a more predictive model of dental bone response and help develop a new design methodology for patient-specific dental prosthetic restoration.

  9. Image-assisted non-invasive and dynamic biomechanical analysis of human joints

    Science.gov (United States)

    Muhit, Abdullah A.; Pickering, Mark R.; Scarvell, Jennifer M.; Ward, Tom; Smith, Paul N.

    2013-07-01

    Kinematic analysis provides a strong link between musculoskeletal injuries, chronic joint conditions, treatment planning/monitoring and prosthesis design/outcome. However, fast and accurate 3D kinematic analysis still remains a challenge in order to translate this procedure into clinical scenarios. 3D computed tomography (CT) to 2D single-plane fluoroscopy registration is a promising non-invasive technology for biomechanical examination of human joints. Although this technique has proven to be very precise in terms of in-plane translation and rotation measurements, out-of-plane motion estimations have been a difficulty so far. Therefore, to enable this technology into clinical translation, precise and fast estimation of both in-plane and out-of-plane movements is crucial, which is the aim of this paper. Here, a fast and accurate 3D/2D registration technique is proposed to evaluate biomechanical/kinematic analysis. The proposed algorithm utilizes a new multi-modal similarity measure called ‘sum of conditional variances’, a coarse-to-fine Laplacian of Gaussian filtering approach for robust gradient-descent optimization and a novel technique for the analytic calculation of the required gradients for out-of-plane rotations. Computer simulations and in vitro experiments showed that the new approach was robust in terms of the capture range, required significantly less iterations to converge and achieved good registration and kinematic accuracy when compared to existing techniques and to the ‘gold-standard’ Roentgen stereo analysis.

  10. A selection of biomechanical research problems: From modeling to experimentation

    Science.gov (United States)

    Abbasi, Cyrus Omid

    The research undertakings within this manuscript illustrate the importance of biomechanics in today's science. Without doubt, biomechanics can be utilized to obtain a better understanding of many unsolved mysteries involved in the field of medicine. Moreover, biomechanics can be used to develop better prosthetic or surgical devices as well. Chapter 2 represents a medical problem, which has not been solved for more than a century. With the use of fundamental principles of biomechanics', a better insight of this problem and its possible causes were obtained. Chapter 3 investigates the mechanical interaction between the human teeth and some processed food products during mastication, which is a routine but crucial daily activity of a human being. Chapter 4 looks at a problem within the field of surgery. In this chapter the stability and reliability of two different Suturing-Techniques are explored. Chapters 5 and 6 represent new patent designs as a result of the investigations made in Chapter 4. Chapter 7 studies the impact and load transfer patterns during the collision between a child's head and the ground. All of the above mentioned chapters show the significance of biomechanics in solving a range of different medical problems that involve physical and or mechanical characters.

  11. Antioxidant Activity and Antibacterial Effects on Clinical Isolated Streptococcus suis and Staphylococcus intermedius of Extracts from Several Parts of Cladogynos orientalis and Their Phytochemical Screenings

    OpenAIRE

    Pongtip Sithisarn; Piyanuch Rojsanga; Patchima Sithisarn; Sumet Kongkiatpaiboon

    2015-01-01

    The in vitro antioxidant and antibacterial assays against clinically isolated Streptococcus suis and Staphylococcus intermedius of the extracts prepared by decoction and ethanolic reflux of different parts of Chettaphangki (Cladogynos orientalis Zipp. ex Span), including the leaves, roots, and stems, using 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay and disc diffusion method were conducted. Quantitative analysis of total phenolic and total flavonoid contents in the extracts using sp...

  12. Clinical and histological challenge in the differential diagnosis of diffuse alopecia: female androgenetic alopecia, telogen effluvium and alopecia areata - Part II *

    OpenAIRE

    Betina Werner; Fabiane Mulinari-Brenner

    2012-01-01

    Diffuse alopecia is mainly caused by telogen effluvium, diffuse androgenetic alopecia (femalepattern hair loss) and diffuse alopecia areata. Differential diagnosis between the three disorders may be difficult in several occasions. In this second part of our study, chronic telogen effluvium and diffuse alopecia areata are discussed in detail, including clinical, dermoscopic and histological aspects. A flowchart presents a practical and objective differential diagnostic approach to diffuse alop...

  13. Electronic apex locator: A comprehensive literature review — Part II: Effect of different clinical and technical conditions on electronic apex locator′s accuracy

    Directory of Open Access Journals (Sweden)

    Hamid Razavian

    2014-01-01

    Full Text Available Introduction: To investigate the effects of different clinical and technical conditions on the accuracy of electronic apex locators (EALs. Materials and Methods: "Tooth apex," "dental instrument," "odontometry," "electronic medical," and "electronic apex locator" were searched as primary identifiers via Medline/PubMed, Cochrane library, and Scopus data base up to 30 July 2013. Original articles that fulfilled the inclusion criteria were selected and reviewed. Results: Out of 402 relevant studies, 183 were selected based on the inclusion criteria. In this part, 75 studies are presented. Pulp vitality conditions and root resorption, types of files and irrigating materials do not affect an EAL′s accuracy; however, the file size and foramen diameter can affect its accuracy. Conclusions: Various clinical conditions such as the file size and foramen diameter may affect EALs′ accuracy. However, more randomized clinical trials are needed for definitive conclusion.

  14. Challenges relating to solid tumour brain metastases in clinical trials, part 1: patient population, response, and progression. A report from the RANO group.

    Science.gov (United States)

    Lin, Nancy U; Lee, Eudocia Q; Aoyama, Hidefumi; Barani, Igor J; Baumert, Brigitta G; Brown, Paul D; Camidge, D Ross; Chang, Susan M; Dancey, Janet; Gaspar, Laurie E; Harris, Gordon J; Hodi, F Stephen; Kalkanis, Steven N; Lamborn, Kathleen R; Linskey, Mark E; Macdonald, David R; Margolin, Kim; Mehta, Minesh P; Schiff, David; Soffietti, Riccardo; Suh, John H; van den Bent, Martin J; Vogelbaum, Michael A; Wefel, Jeffrey S; Wen, Patrick Y

    2013-09-01

    Therapeutic outcomes for patients with brain metastases need to improve. A critical review of trials specifically addressing brain metastases shows key issues that could prevent acceptance of results by regulatory agencies, including enrolment of heterogeneous groups of patients and varying definitions of clinical endpoints. Considerations specific to disease, modality, and treatment are not consistently addressed. Additionally, the schedule of CNS imaging and consequences of detection of new or progressive brain metastases in trials mainly exploring the extra-CNS activity of systemic drugs are highly variable. The Response Assessment in Neuro-Oncology (RANO) working group is an independent, international, collaborative effort to improve the design of trials in patients with brain tumours. In this two-part series, we review the state of clinical trials of brain metastases and suggest a consensus recommendation for the development of criteria for future clinical trials. PMID:23993384

  15. The Current Testing Protocols for Biomechanical Evaluation of Lumbar Spinal Implants in Laboratory Setting: A Review of the Literature

    Directory of Open Access Journals (Sweden)

    Sabrina A. Gonzalez-Blohm

    2015-01-01

    Full Text Available In vitro biomechanical investigations have become a routinely employed technique to explore new lumbar instrumentation. One of the most important advantages of such investigations is the low risk present when compared to clinical trials. However, the best use of any experimental data can be made when standard testing protocols are adopted by investigators, thus allowing comparisons among studies. Experimental variables, such as the length of the specimen, operative level, type of loading (e.g., dynamic versus quasistatic, magnitude, and rate of load applied, are among the most common variables controlled during spinal biomechanical testing. Although important efforts have been made to standardize these protocols, high variability can be found in the current literature. The aim of this investigation was to conduct a systematic review of the literature to identify the current trends in the protocols reported for the evaluation of new lumbar spinal implants under laboratory setting.

  16. Do cells contribute to tendon and ligament biomechanics?

    Directory of Open Access Journals (Sweden)

    Niels Hammer

    Full Text Available Acellular scaffolds are increasingly used for the surgical repair of tendon injury and ligament tears. Despite this increased use, very little data exist directly comparing acellular scaffolds and their native counterparts. Such a comparison would help establish the effectiveness of the acellularization procedure of human tissues. Furthermore, such a comparison would help estimate the influence of cells in ligament and tendon stability and give insight into the effects of acellularization on collagen.Eighteen human iliotibial tract samples were obtained from nine body donors. Nine samples were acellularized with sodium dodecyl sulphate (SDS, while nine counterparts from the same donors remained in the native condition. The ends of all samples were plastinated to minimize material slippage. Their water content was adjusted to 69%, using the osmotic stress technique to exclude water content-related alterations of the mechanical properties. Uniaxial tensile testing was performed to obtain the elastic modulus, ultimate stress and maximum strain. The effectiveness of the acellularization procedure was histologically verified by means of a DNA assay.The histology samples showed a complete removal of the cells, an extensive, yet incomplete removal of the DNA content and alterations to the extracellular collagen. Tensile properties of the tract samples such as elastic modulus and ultimate stress were unaffected by acellularization with the exception of maximum strain.The data indicate that cells influence the mechanical properties of ligaments and tendons in vitro to a negligible extent. Moreover, acellularization with SDS alters material properties to a minor extent, indicating that this method provides a biomechanical match in ligament and tendon reconstruction. However, the given protocol insufficiently removes DNA. This may increase the potential for transplant rejection when acellular tract scaffolds are used in soft tissue repair. Further research

  17. Do Cells Contribute to Tendon and Ligament Biomechanics?

    Science.gov (United States)

    Hammer, Niels; Huster, Daniel; Fritsch, Sebastian; Hädrich, Carsten; Koch, Holger; Schmidt, Peter; Sichting, Freddy; Wagner, Martin Franz-Xaver; Boldt, Andreas

    2014-01-01

    Introduction Acellular scaffolds are increasingly used for the surgical repair of tendon injury and ligament tears. Despite this increased use, very little data exist directly comparing acellular scaffolds and their native counterparts. Such a comparison would help establish the effectiveness of the acellularization procedure of human tissues. Furthermore, such a comparison would help estimate the influence of cells in ligament and tendon stability and give insight into the effects of acellularization on collagen. Material and Methods Eighteen human iliotibial tract samples were obtained from nine body donors. Nine samples were acellularized with sodium dodecyl sulphate (SDS), while nine counterparts from the same donors remained in the native condition. The ends of all samples were plastinated to minimize material slippage. Their water content was adjusted to 69%, using the osmotic stress technique to exclude water content-related alterations of the mechanical properties. Uniaxial tensile testing was performed to obtain the elastic modulus, ultimate stress and maximum strain. The effectiveness of the acellularization procedure was histologically verified by means of a DNA assay. Results The histology samples showed a complete removal of the cells, an extensive, yet incomplete removal of the DNA content and alterations to the extracellular collagen. Tensile properties of the tract samples such as elastic modulus and ultimate stress were unaffected by acellularization with the exception of maximum strain. Discussion The data indicate that cells influence the mechanical properties of ligaments and tendons in vitro to a negligible extent. Moreover, acellularization with SDS alters material properties to a minor extent, indicating that this method provides a biomechanical match in ligament and tendon reconstruction. However, the given protocol insufficiently removes DNA. This may increase the potential for transplant rejection when acellular tract scaffolds are used in

  18. Ultrasound Elasticity Imaging System with Chirp-Coded Excitation for Assessing Biomechanical Properties of Elasticity Phantom

    Directory of Open Access Journals (Sweden)

    Guan-Chun Chun

    2015-12-01

    Full Text Available The biomechanical properties of soft tissues vary with pathological phenomenon. Ultrasound elasticity imaging is a noninvasive method used to analyze the local biomechanical properties of soft tissues in clinical diagnosis. However, the echo signal-to-noise ratio (eSNR is diminished because of the attenuation of ultrasonic energy by soft tissues. Therefore, to improve the quality of elastography, the eSNR and depth of ultrasound penetration must be increased using chirp-coded excitation. Moreover, the low axial resolution of ultrasound images generated by a chirp-coded pulse must be increased using an appropriate compression filter. The main aim of this study is to develop an ultrasound elasticity imaging system with chirp-coded excitation using a Tukey window for assessing the biomechanical properties of soft tissues. In this study, we propose an ultrasound elasticity imaging system equipped with a 7.5-MHz single-element transducer and polymethylpentene compression plate to measure strains in soft tissues. Soft tissue strains were analyzed using cross correlation (CC and absolution difference (AD algorithms. The optimal parameters of CC and AD algorithms used for the ultrasound elasticity imaging system with chirp-coded excitation were determined by measuring the elastographic signal-to-noise ratio (SNRe of a homogeneous phantom. Moreover, chirp-coded excitation and short pulse excitation were used to measure the elasticity properties of the phantom. The elastographic qualities of the tissue-mimicking phantom were assessed in terms of Young’s modulus and elastographic contrast-to-noise ratio (CNRe. The results show that the developed ultrasound elasticity imaging system with chirp-coded excitation modulated by a Tukey window can acquire accurate, high-quality elastography images.

  19. Biomechanical Effect of an Interlaminar Device on Ranges of Motion, Intradiscal Pressure, and Centers of Rotation

    Directory of Open Access Journals (Sweden)

    Giancarlo Guizzardi

    2015-06-01

    Full Text Available Introduction. The IntraSPINE is a new interlaminar device that has been proposed with the aim to decompress the spinal canal without reducing the extension motion. The purpose of this study was therefore to evaluate the biomechanical behavior of L4-L5 spinal units implanted with this interlaminar device, in terms of ranges of motion, intradiscal pressure, and centers of rotation. Material and Methods. Six human lumbar spines were harvested within 10 days after death. A specific spine testing device was used to apply moments up to 10 Nm in flexion-extension, lateral bending (left-right flexion and left-right axial rotation (torsion, with measurement of vertebral 3D motion and of intervertebral disc pressure. Protocol was repeated for each specimen in 5 configurations: intact specimen; after L4-L5 bilateral medial hemifacetectomy and both yellow ligament resection; after implantation of the interlaminar device at the L4-L5 level; after removal of the L4-L5 supraspinous ligament, resection of the posterior third of the disc and addition of an artificial ligament; after device and artificial ligament removal. Results. The implant reduced increases in segmental flexion seen following injury particularly when applied with the artificial ligament. Intradiscal pressure reduced following application of the implant without reducing extension range. A small posterior shift of the Mean Centers of Rotation (MCR was noticed after instrumentation. Torsion and lateral bending range was unaffected by the interlaminar device. Conclusion. This biomechanical study yields a better understanding of this interlaminar implant effect. A large clinical trial with follow-up would be required to evaluate and confirm in vivo the observed in vitro biomechanical behavior of the device.

  20. Biomechanical approaches to understanding the potentially injurious demands of gymnastic-style impact landings

    Directory of Open Access Journals (Sweden)

    Gittoes Marianne JR

    2012-01-01

    effectiveness of gymnastics injury counter measures has been advocated over the past decade, a lack of information based on randomised controlled studies or actual evaluation of counter measures in the field setting has been highlighted. The subsequent integration of insight into biomechanical risk factors of landing with clinical practice interventions has been recently advocated.

  1. Fatigue behavior of Ilizarov frame versus tibial interlocking nail in a comminuted tibial fracture model: a biomechanical study

    Directory of Open Access Journals (Sweden)

    Stahel Philip F

    2006-12-01

    Full Text Available Abstract Background Treatment options for comminuted tibial shaft fractures include plating, intramedullary nailing, and external fixation. No biomechanical comparison between an interlocking tibia nail with external fixation by an Ilizarov frame has been reported to date. In the present study, we compared the fatigue behaviour of Ilizarov frames to interlocking intramedullary nails in a comminuted tibial fracture model under a combined loading of axial compression, bending and torsion. Our goal was to determine the biomechanical characteristics, stability and durability for each device over a clinically relevant three month testing period. The study hypothesis was that differences in the mechanical properties may account for differing clinical results and provide information applicable to clinical decision making for comminuted tibia shaft fractures. Methods In this biomechanical study, 12 composite tibial bone models with a comminuted fracture and a 25 mm diaphyseal gap were investigated. Of these, six models were stabilized with a 180-mm four-ring Ilizarov frame, and six models were minimally reamed and stabilized with a 10 mm statically locked Russell-Taylor Delta™ tibial nail. After measuring the pre-fatigue axial compression bending and torsion stiffness, each model was loaded under a sinusoidal cyclic combined loading of axial compression (2.8/28 lbf; 12.46/124.6 N and torque (1.7/17 lbf-in; 0.19/1.92 Nm at a frequency of 3 Hz. The test was performed until failure (implant breakage or ≥ 5° angulations and/or 2 cm shortening occurred or until 252,000 cycles were completed, which corresponds to approximately three months testing period. Results In all 12 models, both the Ilizarov frame and the interlocking tibia nail were able to maintain fracture stability of the tibial defect and to complete the full 252,000 cycles during the entire study period of three months. A significantly higher stiffness to axial compression and torsion was

  2. Biomechanics of Kuzushi-Tsukuri and Interaction in Competition

    CERN Document Server

    Sacripanti, Attilio

    2010-01-01

    In this paper it is performed the comparative biomechanical analysis of the Kuzushi (Unbalance) -Tsukuri (the entry and proper fitting of Tori's body into the position taken just before throwing) phases of Judo Throwing techniques. The whole effective movement is without separation, as already stated by old Japanese biomechanical studies (1972 -1978), only one skilled connected action, but the biomechanical analysis is able to separate the whole in didactic steps called Action Invariants. The first important finding singled out is the existence of two classes of Action Invariants the first the General one' connected to the whole body motion is specific of shortening distance in the Kuzushi Tsukuri Phase. The second one, the Specific Action Invariants is connected to the superior and inferior kinetic chains motion and right positioning connected both to Kuzushi and Tsukuri phases. Some interesting findings derive from this analysis: among throwing techniques, couple techniques could be independent from Kuzushi...

  3. Computational biomechanics for medicine new approaches and new applications

    CERN Document Server

    Miller, Karol; Wittek, Adam; Nielsen, Poul

    2015-01-01

    The Computational Biomechanics for Medicine titles provide an opportunity for specialists in computational biomechanics to present their latest methodologiesand advancements. Thisvolumecomprises twelve of the newest approaches and applications of computational biomechanics, from researchers in Australia, New Zealand, USA, France, Spain and Switzerland. Some of the interesting topics discussed are:real-time simulations; growth and remodelling of soft tissues; inverse and meshless solutions; medical image analysis; and patient-specific solid mechanics simulations. One of the greatest challenges facing the computational engineering community is to extend the success of computational mechanics to fields outside traditional engineering, in particular to biology, the biomedical sciences, and medicine. We hope the research presented within this book series will contribute to overcoming this grand challenge.

  4. Biomechanics of Wheat/Barley Straw and Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Christopher T. Wright; Peter A. Pryfogle; Nathan A. Stevens; Eric D. Steffler; J. Richard Hess; Thomas H. Ulrich

    2005-03-01

    The lack of understanding of the mechanical characteristics of cellulosic feedstocks is a limiting factor in economically collecting and processing crop residues, primarily wheat and barley stems and corn stover. Several testing methods, including compression, tension, and bend have been investigated to increase our understanding of the biomechanical behavior of cellulosic feedstocks. Biomechanical data from these tests can provide required input to numerical models and help advance harvesting, handling, and processing techniques. In addition, integrating the models with the complete data set from this study can identify potential tools for manipulating the biomechanical properties of plant varieties in such a manner as to optimize their physical characteristics to produce higher value biomass and more energy efficient harvesting practices.

  5. The increasing importance of the biomechanics of impact trauma

    Indian Academy of Sciences (India)

    Murray Mackay

    2007-08-01

    The evolution of experimental biomechanics and crash injury research is summarized briefly to show that they both play a major role in mitigating traffic deaths and injuries. Historically, the subject has been based largely in western countries and thus focused on vehicle occupants, whereas some 80% of traffic casualties in the world are outside the vehicle as pedestrians, cyclists and motorcyclists. The subject is close to the regulatory process which controls vehicle design and is thus heavily influenced by government and industry, yet it is now in an expanding period because of new techniques to replicate the human frame’s response to impact forces. New knowledge is likely to emerge from addressing population variations and combining real world accident investigations with experimental biomechanics. The application of impact biomechanics to the vulnerable road users is of particular importance.

  6. The biomechanical and structural properties of CS2 fimbriae

    CERN Document Server

    Mortezaei, Narges; Zakrisson, Johan; Bullitt, Esther; Andersson, Magnus

    2015-01-01

    Enterotoxigenic Escherichia coli (ETEC) are a major cause of diarrhea worldwide, and infection of children in underdeveloped countries often leads to high mortality rates. Isolated ETEC express a plethora of colonization factors (fimbriae/pili), of which CFA/I and CFA/II that are assembled via the alternate chaperone pathway (ACP), are amongst the most common. Fimbriae are filamentous structures, whose shafts are primarily composed of helically arranged single pilin-protein subunits, with a unique biomechanical capability allowing them to unwind and rewind. A sustained ETEC infection, under adverse conditions of dynamic shear forces, is primarily attributed to this biomechanical feature of ETEC fimbriae. Recent understandings about the role of fimbriae as virulence factors are pointing to an evolutionary adaptation of their structural and biomechanical features. In this work, we investigated the biophysical properties of CS2 fimbriae from the CFA/II group. Homology modelling its major structural subunit CotA ...

  7. Anatomic and functional leg-length inequality: A review and recommendation for clinical decision-making. Part I, anatomic leg-length inequality: prevalence, magnitude, effects and clinical significance

    Directory of Open Access Journals (Sweden)

    Knutson Gary A

    2005-07-01

    Full Text Available Abstract Background Leg-length inequality is most often divided into two groups: anatomic and functional. Part I of this review analyses data collected on anatomic leg-length inequality relative to prevalence, magnitude, effects and clinical significance. Part II examines the functional "short leg" including anatomic-functional relationships, and provides an outline for clinical decision-making. Methods Online database – Medline, CINAHL and MANTIS – and library searches for the time frame of 1970–2005 were done using the term "leg-length inequality". Results and Discussion Using data on leg-length inequality obtained by accurate and reliable x-ray methods, the prevalence of anatomic inequality was found to be 90%, the mean magnitude of anatomic inequality was 5.2 mm (SD 4.1. The evidence suggests that, for most people, anatomic leg-length inequality does not appear to be clinically significant until the magnitude reaches ~ 20 mm (~3/4". Conclusion Anatomic leg-length inequality is near universal, but the average magnitude is small and not likely to be clinically significant.

  8. Formative evaluation of a telemedicine model for delivering clinical neurophysiology services part I: Utility, technical performance and service provider perspective

    Directory of Open Access Journals (Sweden)

    Breen Patricia

    2010-09-01

    Full Text Available Abstract Background Formative evaluation is conducted in the early stages of system implementation to assess how it works in practice and to identify opportunities for improving technical and process performance. A formative evaluation of a teleneurophysiology service was conducted to examine its technical and sociological dimensions. Methods A teleneurophysiology service providing routine EEG investigation was established. Service use, technical performance and satisfaction of clinical neurophysiology personnel were assessed qualitatively and quantitatively. These were contrasted with a previously reported analysis of the need for teleneurophysiology, and examination of expectation and satisfaction with clinical neurophysiology services in Ireland. A preliminary cost-benefit analysis was also conducted. Results Over the course of 40 clinical sessions during 20 weeks, 142 EEG investigations were recorded and stored on a file server at a satellite centre which was 130 miles away from the host clinical neurophysiology department. Using a virtual private network, the EEGs were accessed by a consultant neurophysiologist at the host centre for interpretation. The model resulted in a 5-fold increase in access to EEG services as well as reducing average waiting times for investigation by a half. Technically the model worked well, although a temporary loss of virtual private network connectivity highlighted the need for clarity in terms of responsibility for troubleshooting and repair of equipment problems. Referral quality, communication between host and satellite centres, quality of EEG recordings, and ease of EEG review and reporting indicated that appropriate organisational processes were adopted by the service. Compared to traditional CN service delivery, the teleneurophysiology model resulted in a comparable unit cost per EEG. Conclusion Observations suggest that when traditional organisational boundaries are crossed challenges associated with the

  9. Biomechanical Profile of Danish Elite and Sub-elite Soccer Goalkeepers

    DEFF Research Database (Denmark)

    Sørensen, Henrik; Thomassen, Martin; Zacho, Morten

    2008-01-01

    The purpose of this study was to define a biomechanical profile of the soccer goalkeeper. We tested whether the skill level of 6 goalkeepers correlated with a number of biomechanical tests. The skill level of each goalkeeper was defined as the league he played in. The biomechanical tests were...

  10. Susceptibility of some clinical isolates of Staphylococcus aureus to fractions from the aerial parts of Leuzea carthamoides

    Czech Academy of Sciences Publication Activity Database

    Janovská, D.; Klouček, P.; Urban, J.; Vaněk, Tomáš; Rada, V.; Kokoška, L.

    2008-01-01

    Roč. 63, č. 5 (2008), s. 607-609. ISSN 0006-3088 R&D Projects: GA MŠk 1P04OC926.001 Institutional research plan: CEZ:AV0Z50380511 Keywords : Leuzea carthamoides * aerial parts * antimicrobial activity Subject RIV: CE - Biochemistry Impact factor: 0.406, year: 2008

  11. The modern biomechanics technology in practice of preparedness athletes.

    Directory of Open Access Journals (Sweden)

    Akhmetov R.F.

    2011-01-01

    Full Text Available The generalized information about directions of application of biomechanics technologies in modern sport is resulted. Some aspects of the use of biomechanics ergogenical tools of the moved delayed action in the system of preparation of athletes-jumpers are considered. Presents the possibility of using training complex «easy leading» for perfection of structure of motive actions of sportsmen, specialized in high jumps. The introduction of a vast arsenal of technical tools in practice the training process open new prospects associated with increased efficiency in the preparation of athletes.

  12. Forward lunge knee biomechanics before and after partial meniscectomy

    DEFF Research Database (Denmark)

    Hall, Michelle; Nielsen, Jonas Høberg; Holsgaard-Larsen, Anders;

    2015-01-01

    partial meniscectomy (APM) on knee joint mechanics. The purpose of this study was to evaluate changes in knee joint biomechanics during a forward lunge in patients with a suspected degenerative meniscal tear from before to three months after APM. METHODS: Twenty-two patients (35-55years old......) with a suspected degenerative medial meniscal tear participated in this study. Three dimensional knee biomechanics were assessed on the injured and contralateral leg before and three months after APM. The visual analogue scale was used to assess knee pain and the Knee Injury Osteoarthritis Outcome Score was used...

  13. Advances in compression nails - principles and biomechanical photoelastic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Mittelmeier, W.; Hauschild, M.; Bader, R.; Steinhauser, E. [Technische Univ. Muenchen (Germany). Klinik fuer Orthopaedie und Sportorthopaedie

    2001-12-01

    The nail-osteosynthesis is an established concept for shaft-fractures of long bones. The compression-nail ICN enables a favourable primary-stability and also a former full weight-bearing over a precompression of the nail-bone-system. The indications of the compression-nail include beside more diaphyseal cross fractures and short oblique fractures non-unions and correction-osteotomies. Newer modular nail-types like the tandem compression nail (TCN) can improve the biomechanical prerequisites of the compression nail principle. Key-words: internal fixation - interlocking-nail - modular - compression - biomechanics - non-union (orig.)

  14. Hand kinematics: Application in clinical practice

    Directory of Open Access Journals (Sweden)

    Santosh Rath

    2011-01-01

    Full Text Available Pathological conditions of the hand consequent to injuries, paralysis, disease, arthritis and congenital difference results in loss or limitation of function, deformities, stiffness, inadequate power and poor position for pinch. The pathogenesis of deformities is influenced by bio-mechanical principles of joints and muscle function. The crippling impact of secondary changes due to edema, soft tissue contractures, muscle shortening and functional adaptations also have a mechanical basis. For clinicians and hand therapists, it is necessary to understand these fundamental principles of biomechanics to plan treatment modalities. Interpretation of mechanics of hand deformities in rheumatoid arthritis and paralysis will enable the treating team to identify the appropriate interventions of splinting, therapy and surgical procedures. Basic knowledge of the principles of hand clinical bio-mechanics will help the beginner to sail through the multitude of tendon transfers described in the text books of hand surgery and find the best solution for a particular clinical presentation. Similarly, knowledge of bio-mechanics will provide solutions to an experienced surgeon to plan treatment protocols for complex situations. The article presents a concise summary of the basic principles of hand bio-mechanics for common hand conditions seen in clinical practice. Understanding and applying these principles will help clinicians in planning and devising treatment options for common and complex hand conditions.

  15. Safety evaluation of daidzein in laying hens: part I. Effects on laying performance, clinical blood parameters, and organs development.

    Science.gov (United States)

    Shi, S R; Gu, H; Chang, L L; Wang, Z Y; Tong, H B; Zou, J M

    2013-05-01

    Daidzein, an estrogen-like product, becomes increasingly popular as a dietary supplement, particularly for postpeak-estrus animals seeking a safe natural alternative to play a role of estrogen. However, there is little available safety data of it for raisers and consumers. A subchronic laying hen safety study was conducted to examine if the high-dose daidzein could affect the safety of hens selves, including laying performance, clinical blood parameters and organs development. Seven hundred and sixty-eight 56-week-old Hyline Brown were randomly assigned to 4 groups with 8 replicates of 24 birds each and 3weeks later fed diets supplemented with 0, 10, 50 and 100mg of daidzein/kg for 12weeks. The mortality was significantly decreased (P0.05). In clinical chemistry parameters, total protein, total cholesterol, calcium and phosphorus were significantly affected by dietary daidzein supplement (P<0.05). The no observed adverse effect level (NOAEL) is considered to be 50mg/kg. PMID:23391597

  16. [Pre-psychotic states--contemporary diagnostic and therapeutic issues. Part I. Clinical identification of pre-psychotic states].

    Science.gov (United States)

    Czernikiewicz, Andrzej; Szulc, Agata

    2007-01-01

    Early intervention in psychotic disorders, particularly schizophrenia, has been increasingly recognized as important by clinicians. The benefits of early intervention in schizophrenia to patients include prevention of neurobiological changes, minimization of secondary morbidity and prevention of relapse. Other benefits of prepsychotic intervention include the capacity to research the onset phase of psychosis. We would like to support in our paper a statement by Maeres: What is needed is not diagnosing the early stages of schizophrenia but the diagnosis of prepsychotic schizophrenia. We are interested in recognizing the schizophrenia 'prodrome' prospectively using to concepts: subjects 'at risk mental state' (ARMS) and subjects from 'ultra high risk' (UHR) group. For clinical reasons that involves both some clinical features of pre-psychotic states (attenuated psychotic symptoms) and some "trait factors", i.e. schizotypal personality or family predisposition factors. Recent data revealed that some characteristics of pre-psychotic states had stronger predictive value: longer symptoms duration, lower level of GAF (< 40), and presence of attenuated psychotic symptoms. The possibility of providing intervention prior to the onset of psychosis has risen from recent interest in early intervention in these pre-psychotic states. PMID:17494410

  17. Biomechanical exploration on dynamic modes of lifting.

    Science.gov (United States)

    Gagnon, M; Smyth, G

    1992-03-01

    Whatever the lifting method used, dynamic factors appear to have an effect on the safe realization of movement, and NIOSH guidelines recommend smooth lifting with no sudden acceleration effects. On the other hand, inertial forces may play an important role in the process of transfer of momentum to the load. The direction by which these inertial forces may affect the loadings on body structures and processes of energy transfers cannot be determined a priori. A biomechanical experiment was performed to examine if there were differences in the execution processes between a slow-continuous lift and an accelerated-continuous lift, and also between accelerated lifts either executed continuously or interrupted with a pause. The lifts were executed from a height of 15 cm to a height of 185 cm above the head and with two different loads (6.4 and 11.6 kg). Five experienced workers in manual materials handling were used as subjects. Films and force platforms recordings supplied the data; dynamic segmental analyses were performed to calculate net muscular moments at each joint; a planar single-muscle equivalent was used to estimate compression loadings at L5/S1; total mechanical work, joint work distribution, and energy transfers were determined from a kinetic approach based on the integration of joint power as a function of time. Analyses of variance with repeated measures were applied to the three treatments. The results showed that joint muscular moments, spinal loadings, mechanical work, and muscular utilization ratios were generally increased by the presence of acceleration without inducing benefits of improved energy transfers; therefore slower lifts with reduced acceleration may be safer when handling moderately heavy loads. The maximum values of kinematic and kinetic factors were generally not affected by the pause, but the occurrence of jerks in the movement (acceleration, ground forces, and muscular moments) suggests that the pause may not be indicated when

  18. Computer assisted self interviewing in a sexual health clinic as part of routine clinical care; impact on service and patient and clinician views.

    Directory of Open Access Journals (Sweden)

    Lenka A Vodstrcil

    Full Text Available BACKGROUND: Computer assisted self interviewing (CASI has been used at the Melbourne Sexual Health Centre (MSHC since 2008 for obtaining sexual history and identifying patients' risk factors for sexually transmitted infections (STIs. We aimed to evaluate the impact of CASI operating at MSHC. METHODOLOGY/PRINCIPAL FINDINGS: The proportion of patients who decline to answer questions using CASI was determined. We then compared consultation times and STI-testing rates during comparable CASI and non-CASI operating periods. Patients and staff completed anonymous questionnaires about their experience with CASI. 14,190 patients completed CASI during the audit period. Men were more likely than women to decline questions about the number of partners they had of the opposite sex (4.4% v 3.6%, p=0.05 and same sex (8.9% v 0%, p<0.001. One third (34% of HIV-positive men declined the number of partners they had and 11-17% declined questions about condom use. Women were more likely than men to decline to answer questions about condom use (2.9% v 2.3%, p=0.05. There was no difference in the mean consultation times during CASI and non-CASI operating periods (p≥0.17. Only the proportion of women tested for chlamydia differed between the CASI and non-CASI period (84% v 88% respectively, p<0.01. 267 patients completed the survey about CASI. Most (72% men and 69% women were comfortable using the computer and reported that all their answers were accurate (76% men and 71% women. Half preferred CASI but 18% would have preferred a clinician to have asked the questions. 39 clinicians completed the staff survey. Clinicians felt that for some STI risk factors (range 11%-44%, face-to-face questioning was more accurate than CASI. Only 5% were unsatisfied with CASI. CONCLUSIONS: We have demonstrated that CASI is acceptable to both patients and clinicians in a sexual health setting and does not adversely affect various measures of clinical output.

  19. Wrist joint moments of walker-assisted gait:a study of biomechanics and instrumentation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    While walkers are commonly prescribed to improve patient stability and ambulatory ability,quantitativestudy of the biomechanical and functional requirements for effective walker use is limited.To investigate the changesin wrist joint moments that occur with the use of a standard walker,a strain gauge-based walker instrumentation system was developed for the measurement of wrist joint moments.This walker dynamometer was integrated with an upper extremity biomechanical model.Preliminary system data were collected for twelve healthy,right-handed young adultsfollowing informed consent.Bilateral upper extremity kinematic data were acquired with a six-camera motion analysis system.Internal joint moments at the wrist were determined in the three clinical planes using the inverse dynamics method.Results showed that during a walker-assisted gait there were several typical demands of wrist abductor,adductor,flexor and external rotator.An interesting " bare phase " of wrist joint moments was also found in phaseangle[-30°,30°] of gait cycle.Complete description of wrist joint moments during walker-assisted gait may provide insight into walker use parameters and rehabilitative strategies.

  20. Biomechanical evaluation of a corporectomy in porcine lumbar specimens using flexible polymer belts

    Science.gov (United States)

    Beltrán-Fernández, J. A.; Hernández-Gómez, L. H.; Ruiz-Muñoz, E.; González-Rebattú, A.; Rodríguez-Cañizo, R. G.; Urriolagoitia-Calderón, G.; Urriolagoitia-Sosa, G.; Hernández-Moreno, H.

    2009-08-01

    This paper presents the experimental results of a biomechanical evaluation in lumbar porcine specimens (L2-L4), instrumented with flexible polymer belts, under fatigue and tensile loading. The clinical effect called facetary arthrosis is evaluated. An experimental analysis was carried on 3 lumbar porcine specimens. In two of them, polyamide belts are fixed on the interspinous ligament from L2 to L4. Specimens are taken from pigs which are 6 month old. For the present work, the stiffness reduction of the spine and the biomechanical behaviour of the belts in conjunction with the interspinous ligament are evaluated. The purpose is to determine the failure conditions for the elements of the specimen (vertebral disk, supra and intraspinous ligament and vertebral body). Under static loading, which is the base line case, the elements of the specimen failed as a typical healthy structure. While in the fatigue combined with static loading, the element failed in different order. Additionally, the stiffness changed in accordance with the fatigue loading conditions. Because of the simplicity of this alternative technique, a high level of the structural integrity is preserved, as no holes are made on the spinous process in order to insert the fixation screws. Furthermore, there is a cost reduction.

  1. Biomechanical evaluation of a corporectomy in porcine lumbar specimens using flexible polymer belts

    International Nuclear Information System (INIS)

    This paper presents the experimental results of a biomechanical evaluation in lumbar porcine specimens (L2-L4), instrumented with flexible polymer belts, under fatigue and tensile loading. The clinical effect called facetary arthrosis is evaluated. An experimental analysis was carried on 3 lumbar porcine specimens. In two of them, polyamide belts are fixed on the interspinous ligament from L2 to L4. Specimens are taken from pigs which are 6 month old. For the present work, the stiffness reduction of the spine and the biomechanical behaviour of the belts in conjunction with the interspinous ligament are evaluated. The purpose is to determine the failure conditions for the elements of the specimen (vertebral disk, supra and intraspinous ligament and vertebral body). Under static loading, which is the base line case, the elements of the specimen failed as a typical healthy structure. While in the fatigue combined with static loading, the element failed in different order. Additionally, the stiffness changed in accordance with the fatigue loading conditions. Because of the simplicity of this alternative technique, a high level of the structural integrity is preserved, as no holes are made on the spinous process in order to insert the fixation screws. Furthermore, there is a cost reduction.

  2. The Emerging Role of Mindfulness Meditation as Effective Self-Management Strategy, Part 2: Clinical Implications for Chronic Pain, Substance Misuse, and Insomnia.

    Science.gov (United States)

    Khusid, Marina A; Vythilingam, Meena

    2016-09-01

    Mindfulness-based interventions have been increasingly utilized in the management of chronic pain since 1982. This second review of a two-part series evaluates the efficacy, mechanism, and safety of mindfulness meditation for chronic pain, substance use disorder, tobacco use disorder, and insomnia frequently co-occurring after return from deployment. Standard databases were searched until August 4, 2015. 72 relevant systematic reviews and clinical trials met the inclusion criteria. The Strength of Recommendation Taxonomy was used to assess the quality of individual studies and to rate the strength of recommendation (SOR) for each clinical condition. Mindfulness-based interventions effectively and durably reduce pain intensity, improve functional status, pain-related psychological consequences, quality of life (SOR B). They can also be utilized as an adjunctive intervention aimed at improving health-related quality of life in individuals with substance use disorders interested in self-management strategies (SOR B). Mindfulness training for smokers used adjunctively with pharmacotherapy shows efficacy in maintaining abstinence comparable to that of the current standard of care (SOR B). Future large, well-designed randomized clinical trials using active controls in service members and veterans with co-occurring pain and psychological health conditions are necessary to provide more precise clinical guidance. PMID:27612339

  3. Evidence-based concepts and procedures for bonded inlays and onlays. Part I. Historical perspectives and clinical rationale for a biosubstitutive approach.

    Science.gov (United States)

    Dietschi, Didier; Spreafico, Roberto

    2015-01-01

    This first article in the series (Part I) aims to present an updated rationale and treatment approach for indirect adhesive posterior restorations based on the best scientific and long-term clinical evidence available. The proposed treatment concept relies on the basic ideas of (1) the placement of an adhesive base/liner (Dual Bonding [DB] and Cavity Design Optimization [CDO]) and, when needed, (2) a simultaneous relocation of deep cervical margins (Cervical Margin Relocation [CMR]), prior to (3) impression taking to ensure a more conservative preparation and easier-to-follow clinical steps, and the use of (4) a highly filled, light-curing restorative material for the cementation (Controlled Adhesive Cementation [CAC]), together with restoration insertion facilitation, the application of sonic/ultrasonic energy, and/or material heating. The suggested clinical protocol will help the practitioner to eliminate the most frequently experienced difficulties relating to the preparation, isolation, impression taking and cementation of tooth-colored inlays and onlays. This protocol can be applied to both ceramics and composites as no material has been proven to be the most feasible or reliable in all clinical indications regarding its physicochemical and handling characteristics. For the time being, however, we have to regard such indirect restorations as a biosubstitution due to the monolithic nature of the restoration, with still very imperfect replication of the specific natural dentin-enamel assemblage. PMID:25874270

  4. Post-processing, is it a burden or a blessing? Part 1 evaluation of clinical image quality

    International Nuclear Information System (INIS)

    Background: The dynamic range of modern detectors tolerates a higher detector dose or Detector Air Kerma (DAK) without negative effect on image quality. Necessary image quality is closely related to the clinical question: in order to keep the patient dose as low as possible, image quality criteria are needed for each type of radiography. The purpose of this study was to investigate the relation between image quality, described as an overall judgement versus the visibility of well-defined structures, and DAK in clinically accepted radiographs. Methods and materials: 168 AP radiographs of the knee and 152 radiographs of the pelvis were collected randomly in 19 radiologic centres. Six radiologists with at least five-years experience scored the overall image quality and the visibility of seven different anatomic structures, in a controlled environment on a five-point scale, using a Visual Grading Analysis (VGA). The relation between the DAK and the VGA Score (VGAS) was evaluated. Results: The VGAS was 3.92 for the knee and 3.71 for the pelvis. The VGAS for CR and DR were significantly different (p < 0.01). Intra-observer variability was not significant and inter-observer correlations were high and significant. Only for the pelvis radiographs produced with computed radiography, a rather weak but significant correlation was found between DAK and VGAS. Conclusion: The VGA revealed an image quality higher than diagnostically necessary in both datasets, and high inter-observer correlation. Based on the DAK-range, it could be hypothesized that below a certain noise level no further visible improvement of the image quality was reached

  5. Fundamental biomechanics of the spine-What we have learned in the past 25 years and future directions.

    Science.gov (United States)

    Oxland, Thomas R

    2016-04-11

    Since the publication of the 2nd edition of White and Panjabi׳s textbook, Clinical Biomechanics of the Spine in 1990, there has been considerable research on the biomechanics of the spine. The focus of this manuscript will be to review what we have learned in regards to the fundamentals of spine biomechanics. Topics addressed include the whole spine, the functional spinal unit, and the individual components of the spine (e.g. vertebra, intervertebral disc, spinal ligaments). In these broad categories, our understanding in 1990 is reviewed and the important knowledge or understanding gained through the subsequent 25 years of research is highlighted. Areas where our knowledge is lacking helps to identify promising topics for future research. In this manuscript, as in the White and Panjabi textbook, the emphasis is on experimental research using human material, either in vivo or in vitro. The insights gained from mathematical models and animal experimentation are included where other data are not available. This review is intended to celebrate the substantial gains that have been made in the field over these past 25 years and also to identify future research directions. PMID:26706717

  6. Radiographic, densitometric, and biomechanical effects of recombinant canine somatotropin in an unstable ostectomy gap model of bone healing in dogs

    International Nuclear Information System (INIS)

    Objective: To determine the effect of recombinant canine somatotropin (STH) on radiographic, densitometric, and biomechanical aspects of bone healing using an unstable ostectomy gap model. Study Design: After an ostectomy of the midshaft radius, bone healing was evaluated over an 8-week period in control dogs (n = 4) and dogs receiving recombinant canine STH (n = 4). Animals Or Sample Population: Eight sexually intact female Beagle dogs, 4 to 5 years old. Methods: Bone healing was evaluated by qualitative and quantitative evaluation of serial radiographs every 2 weeks. Terminal dual-energy x-ray absorptiometry and three-point bending biomechanical testing were also performed. Results: Dogs receiving STH had more advanced radiographic healing of ostectomy sites. Bone area, bone mineral content, and bone density were two to five times greater at the ostectomy sites of treated dogs. Ultimate load at failure and stiffness were three and five times greater in dogs receiving STH. Conclusions: Using the ostectomy gap model, recombinant canine STH enhanced the radiographic, densitometric, and biomechanical aspects of bone healing in dogs. Clinical Relevance: Dogs at risk for delayed healing of fractures may benefit from treatment with recombinant canine STH

  7. Quantitative modelling of the biomechanics of the avian syrinx

    DEFF Research Database (Denmark)

    Elemans, Coen P. H.; Larsen, Ole Næsbye; Hoffmann, Marc R.;

    2003-01-01

    We review current quantitative models of the biomechanics of bird sound production. A quantitative model of the vocal apparatus was proposed by Fletcher (1988). He represented the syrinx (i.e. the portions of the trachea and bronchi with labia and membranes) as a single membrane. This membrane acts...

  8. Biomechanics Curriculum: Its Content and Relevance to Movement Sciences

    Science.gov (United States)

    Hamill, Joseph

    2007-01-01

    While the National Association for Sport and Physical Education (NASPE) has outlined a number of learning outcomes for undergraduate biomechanics, there are a number of factors that can influence the curriculum in such courses. These factors create a situation that indeed can influence students and their attitude towards these classes.…

  9. Corneal biomechanical changes following toric soft contact lens wear

    Directory of Open Access Journals (Sweden)

    Somayeh Radaie-Moghadam

    2016-01-01

    Conclusion: CH and CRF decreased significantly one month after fitting toric soft contact lenses while CCT and K mean did not change significantly. Corneal biomechanical parameters may alter with toric soft contact lens use and such changes may have implications with long-term use such lenses.

  10. Biomechanics of the Gastrointestinal Tract in Health and Disease

    DEFF Research Database (Denmark)

    Zhao, Jingbo; Liao, Donghua; Gregersen, Hans

    2010-01-01

    The gastrointestinal (GI) tract is functionally subjected to dimensional changes. Hence, biomechanical properties such as the stress-strain relationships are of particularly importance. These properties vary along the normal GI tract and remodel in response to growth, aging and disease. The biome...

  11. How to Assess the Biomechanical Risk Levels in Beekeeping.

    Science.gov (United States)

    Maina, G; Rossi, F; Baracco, A

    2016-01-01

    Beekeepers are at particular risk of developing work-related musculoskeletal disorders, but many of the studies lack detailed exposure assessment. To evaluate the biomechanical overload exposure in a specific farming activity, a multitasking model has been developed through the characterization of 37 basic operational tasks typical of the beekeeping activity. The Occupational Repetitive Actions (OCRA) Checklist and the National Institute for Occupational Safety and Health (NIOSH) Lifting Index methodologies have been applied to these elementary tasks to evaluate the exposure, and the resulting risk indices have been time-weighted averaged. Finally, an easy access, computer-assisted toolkit has been developed to help the beekeepers in the biomechanical risk assessment process. The risk of biomechanical overload for the upper limbs ranges from acceptable (maintenance and recovery of woody material and honey packaging with dosing machine tasks) to high (distribution of the top supers) risk level. The risk for back injury is always borderline in women and increases with exposure time, whereas it ranges from acceptable to borderline in men. The definition of the biomechanical risk levels allows for planning of corrective actions aimed at preventing and reducing the risk of musculoskeletal disorders through engineering, administrative, and behavioral interventions. The methodology can be used for risk assessment in other mainly manual agricultural activities. PMID:26765780

  12. Computational modelling of biomechanical behaviour of skeletal elements and implants

    Czech Academy of Sciences Publication Activity Database

    Jíra, J.; Jiroušek, Ondřej; Jírová, Jitka

    Anaheim Calgary Zurich : ACTA Press, 2004 - (Hamza, M.), s. 170 ISBN 0-88986-448-9. [Biomechanics /2./. Honolulu (US), 23.08.2004-25.08.2004] Institutional research plan: CEZ:AV0Z2071913 Keywords : FE model of pelvis * skull and long bone * CT scan Subject RIV: FI - Traumatology, Orthopedics

  13. A review of probabilistic analysis in orthopaedic biomechanics

    OpenAIRE

    Laz, P.J.; Browne, M.

    2010-01-01

    Probabilistic analysis methods are being increasingly applied in the orthopaedics and biomechanics literature to account for uncertainty and variability in subject geometries, properties of various structures, kinematics and joint loading, as well as uncertainty in implant alignment. As a complement to experiments, finite element modelling, and statistical analysis, probabilistic analysis provides a method of characterizing the potential impact of variability in parameters on performa...

  14. The Biomechanical Implications of Obesity in K-12 Learners

    Science.gov (United States)

    Strohmeyer, Scott

    2007-01-01

    Few biomechanical studies have examined obese individuals as primary subjects. However, some mechanical differences have been identified between overweight or obese individuals and nonoverweight movers. It is not clear how obesity affects the onset of osteoarthritis, for example, but it is evident that obesity does place significant limitations on…

  15. Pathobiology of obesity and osteoarthritis: integrating biomechanics and inflammation

    Directory of Open Access Journals (Sweden)

    Rita I. Issa

    2012-05-01

    Full Text Available Obesity is a significant risk factor for developing osteoarthritis in weight-bearing and non-weight-bearing joints. Although the pathogenesis of obesity-associated osteoarthritis is not completely understood, recent studies indicate that pro-inflammatory metabolic factors contribute to an increase in osteoarthritis risk. Adipose tissue, and in particular infrapatellar fat, is a local source of pro-inflammatory mediators that are increased with obesity and have been shown to increase cartilage degradation in cell and tissue culture models. One adipokine in particular, leptin, may be a critical mediator of obesity-associated osteoarthritis via synergistic actions with other inflammatory cytokines. Biomechanical factors may also increase the risk of osteoarthritis by activating cellular inflammation and promoting oxidative stress. However, some types of biomechanical stimulation, such as physiologic cyclic loading, inhibit inflammation and protect against cartilage degradation. A high percentage of obese individuals with knee osteoarthritis are sedentary, suggesting that a lack of physical activity may increase the susceptibility to inflammation. A more comprehensive approach to understanding how obesity alters daily biomechanical exposures within joint tissues may provide new insight into the protective and damaging effects of biomechanical factors on inflammation in osteoarthritis.

  16. A highly versatile autonomous underwater vehicle with biomechanical propulsion

    NARCIS (Netherlands)

    Simons, D.G.; Bergers, M.M.C.; Henrion, S.; Hulzenga, J.I.J.; Jutte, R.W.; Pas, W.M.G.; Van Schravendijk, M.; Vercruyssen, T.G.A.; Wilken, A.P.

    2009-01-01

    An autonomous underwater vehicle with a biomechanical propulsion system is a possible answer to the demand for small, silent sensor platforms in many fields. The design of Galatea, a bio-mimetic AUV, involves four aspects: hydrodynamic shape, the propulsion, the motion control systems and payload. T

  17. Biomechanics of the elbow joint in tennis players.

    NARCIS (Netherlands)

    Eygendaal, D.; Rahussen, F.T.; Diercks, R.L.

    2007-01-01

    Elbow injuries constitute a sizeable percentage of tennis injuries. A basic understanding of biomechanics of tennis and analysis of forces, loads and motions of the elbow during tennis can will improve the understanding of the pathophysiology of these injuries. All different strokes in tennis have a

  18. Computational biomechanics and experimental validation of vessel deformation based on 4D-CT imaging of the porcine aorta

    Science.gov (United States)

    Hazer, Dilana; Finol, Ender A.; Kostrzewa, Michael; Kopaigorenko, Maria; Richter, Götz-M.; Dillmann, Rüdiger

    2009-02-01

    Cardiovascular disease results from pathological biomechanical conditions and fatigue of the vessel wall. Image-based computational modeling provides a physical and realistic insight into the patient-specific biomechanics and enables accurate predictive simulations of development, growth and failure of cardiovascular disease. An experimental validation is necessary for the evaluation and the clinical implementation of such computational models. In the present study, we have implemented dynamic Computed-Tomography (4D-CT) imaging and catheter-based in vivo measured pressures to numerically simulate and experimentally evaluate the biomechanics of the porcine aorta. The computations are based on the Finite Element Method (FEM) and simulate the arterial wall response to the transient pressure-based boundary condition. They are evaluated by comparing the numerically predicted wall deformation and that calculated from the acquired 4D-CT data. The dynamic motion of the vessel is quantified by means of the hydraulic diameter, analyzing sequences at 5% increments over the cardiac cycle. Our results show that accurate biomechanical modeling is possible using FEM-based simulations. The RMS error of the computed hydraulic diameter at five cross-sections of the aorta was 0.188, 0.252, 0.280, 0.237 and 0.204 mm, which is equivalent to 1.7%, 2.3%, 2.7%, 2.3% and 2.0%, respectively, when expressed as a function of the time-averaged hydraulic diameter measured from the CT images. The present investigation is a first attempt to simulate and validate vessel deformation based on realistic morphological data and boundary conditions. An experimentally validated system would help in evaluating individual therapies and optimal treatment strategies in the field of minimally invasive endovascular surgery.

  19. A comparison of the biomechanical effects of valgus knee braces and lateral wedged insoles in patients with knee osteoarthritis.

    Science.gov (United States)

    Jones, Richard K; Nester, Christopher J; Richards, Jim D; Kim, Winston Y; Johnson, David S; Jari, Sanjiv; Laxton, Philip; Tyson, Sarah F

    2013-03-01

    Increases in the external knee adduction moment (EKAM) have been associated with increased mechanical load at the knee and progression of knee osteoarthritis. Valgus knee braces and lateral wedged insoles are common approaches to reducing this loading; however no study has directly compared the biomechanical and clinical effects of these two treatments in patients with medial tibiofemoral osteoarthritis. A cross-over randomised design was used where each intervention was worn by 28 patients for a two week period. Pre- and post-intervention gait kinematic/kinetic data and clinical outcomes were collected to evaluate the biomechanical and clinical effects on the knee joint. The valgus knee brace and the lateral wedged insole significantly increased walking speed, reduced the early stance EKAM by 7% and 12%, and the knee adduction angular impulse by 8.6 and 16.1% respectively. The lateral wedged insole significantly reduced the early stance EKAM compared to the valgus knee brace (p=0.001). The valgus knee brace significantly reduced the knee varus angle compared to the baseline and lateral wedged insole. Improvements in pain and function subscales were comparable for the valgus knee brace and lateral wedged insole. There were no significant differences between the two treatments in any of the clinical outcomes; however the lateral wedged insoles demonstrated greater levels of acceptance by patients. This is the first study to biomechanically compare these two treatments, and demonstrates that given the potential role of knee loading in osteoarthritis progression, that both treatments reduce this but lateral wedge insoles appear to have a greater effect. PMID:22920242

  20. Energetics, Biomechanics, and Performance in Masters' Swimmers: A Systematic Review.

    Science.gov (United States)

    Ferreira, Maria I; Barbosa, Tiago M; Costa, Mário J; Neiva, Henrique P; Marinho, Daniel A

    2016-07-01

    Ferreira, MI, Barbosa, TM, Costa, MJ, Neiva, HP, and Marinho, DA. Energetics, biomechanics, and performance in masters' swimmers: a systematic review. J Strength Cond Res 30(7): 2069-2081, 2016-This study aimed to summarize evidence on masters' swimmers energetics, biomechanics, and performance gathered in selected studies. An expanded search was conducted on 6 databases, conference proceedings, and department files. Fifteen studies were selected for further analysis. A qualitative evaluation of the studies based on the Quality Index (QI) was performed by 2 independent reviewers. The studies were thereafter classified into 3 domains according to the reported data: performance (10 studies), energetics (4 studies), and biomechanics (6 studies). The selected 15 articles included in this review presented low QI scores (mean score, 10.47 points). The biomechanics domain obtained higher QI (11.5 points), followed by energetics and performance (10.6 and 9.9 points, respectively). Stroke frequency (SF) and stroke length (SL) were both influenced by aging, although SF is more affected than SL. Propelling efficiency (ηp) decreased with age. Swimming performance declined with age. The performance declines with age having male swimmers deliver better performances than female counterparts, although this difference tends to be narrow in long-distance events. One single longitudinal study is found in the literature reporting the changes in performance over time. The remaining studies are cross-sectional designs focusing on the energetics and biomechanics. Overall, biomechanics parameters, such as SF, SL, and ηp, tend to decrease with age. This review shows the lack of a solid body of knowledge (reflected in the amount and quality of the articles published) on the changes in biomechanics, energetics, and performance of master swimmers over time. The training programs for this age-group should aim to preserve the energetics as much as possible and, concurrently, improve the

  1. Definition of biomechanical parameters of technical actions in the martial arts

    Directory of Open Access Journals (Sweden)

    Muntian V.S.

    2013-08-01

    Full Text Available Questions of efficiency of training process and competitive activities are considered. The possibilities of accounting in preparing the athletes of the laws of biomechanics and anthropometric characteristics of individual athletes. The experiment involved 16 qualified athletes (age 19-25 years engaged in hand to hand combat. Revealed that body movement back and forth (back slope protection and application of direct counterattacking punch should be regarded as rotational propulsion. It is shown that the length and mass of the parts of the body affect the moment of inertia. Emphasized that in order to determine the level of technical and tactical skills of athletes should conduct research in the field. The effect of the height-weight indices, the length and mass of parts of the body at the moment of inertia. Established their influence on the speed of the predominantly translational and rotational movements, the timing and energy performance of technical activities.

  2. Judo: how to enhance tactics in competition, biomechanics of combination and action reaction

    CERN Document Server

    Sacripanti, Attilio

    2014-01-01

    This paper is an ideal continuation of the previous one - How to enhance effectiveness of Direct Attack Judo throws -in it there are analyzed the two following parts of Judo tactics in high level competitions: combination, and action-reaction. The paper start with a review of the Japanese approach to Initiative ( Sen) and follows by the biomechanical view of the same subject. High level competitions are the main argument not only of coaches match analysis , but also of a lot of scientific researches. However the connection between these two field that analyze the same subject is very hard . A lot of information are not easily transfer to coaching area. In this paper the effort to give coaching useful information is the primary aspect also at detriment of some formal mechanical information. After a new Operative Classification of throwing techniques , the biomechanical analysis of combination and action-reaction tricks flows in easy way singling out some interesting finding, useful for coaches. With this effor...

  3. Biomechanical properties of ileum after systemic treatment with epithelial growth factor

    Institute of Scientific and Technical Information of China (English)

    Jian Yang; Jing-Bo Zhao; Yan-Jun Zeng; Hans Gregersen

    2003-01-01

    AIM:Systemic treatment with epidermal growth factor (EGF)leads to growth of all parts of the small intestine in normal functioning rats. In this study, we investigated the effect of this growth process on morphometric and biomechanical parameters of ileum.METHODS: Rats were treated with EGF (150 μg@kg-1day-1)or placebo via osmotic minipumps for 2, 4, 7, and 14 days.A segment of ileum was removed. The morphology at noload state and zero-stress state was measured and passive biomechanical properties were assessed using a biaxial test machine (combined inflation and axial stretching).RESULTS: The ileum weight increased after EGF administration. After 4 days' EGF treatment, the wall thickness was increased. Significantly smaller inner perimeters were seen in 4 day and 7 day EGF treatment groups. The opening angle and residual strain began to increase after 7 days' EGF treatment. Wall stiffness, evaluated from the stress-strain curves, showed a continuous decrease in circumferential direction during the first 7 days' EGF treatment. The longitudinal stiffness increased during the first 7 days. The stress-strain curves for both circumferential and longitudinal direction tended to shift back to normal 14days after starting EGF administration.CONCLUSION: EGF can cause significant changes both in the morphology and in the passive mechanical properties of the rat ileum.

  4. Ultrasound evaluation of liver disease in cystic fibrosis as part of an annual assessment clinic: A 9-year review

    International Nuclear Information System (INIS)

    AIM: To review 9 years of annual assessment data in cystic fibrosis (CF) and evaluate the frequency of hepatobiliary abnormalities and the correlation between ultrasound and biochemical findings. MATERIALS AND METHODS: Over a 9-year period (1990-99), 168 children (age range 1-18 years) with CF have undergone an annual assessment which has included clinical, biochemical and ultrasonographic evaluation of the hepatobiliary system. We have retrospectively reviewed the sequential ultrasound reports and correlated them with the contemporaneous biochemical results. RESULTS: A total of 725 ultrasound examinations were performed over the review period. Sixty patients had at least one examination showing an abnormality of liver echo texture and in 39 patients this was a persisting finding. Seven patients (4.2%) developed frank cirrhotic change on ultrasound criteria, while 15 patients (8.9%) had evidence of persistent splenomegaly. Gall-bladder calculi were present in 4.8%. In 176 examinations (24%) there was disparity between the ultrasound findings and aspartate aminotransferase (AST) levels. In 3.0% of cases (five patients) there were persisting abnormalities of liver echo texure and persisting splenomegaly with a normal range AST value. CONCLUSION: No perfect method of assessing hepatobiliary involvement in CF is currently available. Ultrasonographic and biochemical assessment may reflect different aspects of disease progression. Routine use of ultrasound in annual assessment allows identification of a minority of patients with liver changes but with normal biochemistry. Williams, S.M. et al. (2002)

  5. Visualisation to enhance biomechanical tuning of ankle-foot orthoses (AFOs in stroke: study protocol for a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Carse Bruce

    2011-12-01

    Full Text Available Abstract Background There are a number of gaps in the evidence base for the use of ankle-foot orthoses for stroke patients. Three dimensional motion analysis offers an ideal method for objectively obtaining biomechanical gait data from stroke patients, however there are a number of major barriers to its use in routine clinical practice. One significant problem is the way in which the biomechanical data generated by these systems is presented. Through the careful design of bespoke biomechanical visualisation software it may be possible to present such data in novel ways to improve clinical decision making, track progress and increase patient understanding in the context of ankle-foot orthosis tuning. Methods A single-blind randomised controlled trial will be used to compare the use of biomechanical visualisation software in ankle-foot orthosis tuning against standard care (tuning using observation alone. Participants (n = 70 will have experienced a recent hemiplegia (1-12 months and will be identified by their care team as being suitable candidates for a rigid ankle-foot orthosis. The primary outcome measure will be walking velocity. Secondary outcome measures include; lower limb joint kinematics (thigh and shank global orientations & kinetics (knee and hip flexion/extension moments, ground reaction force FZ2 peak magnitude, step length, symmetry ratio based on step length, Modified Ashworth Scale, Modified Rivermead Mobility Index and EuroQol (EQ-5D. Additional qualitative measures will also be taken from participants (patients and clinicians at the beginning and end of their participation in the study. The main aim of the study is to determine whether or not the visualisation of biomechanical data can be used to improve the outcomes of tuning ankle-foot orthoses for stroke patients. Discussion In addition to answering the primary research question the broad range of measures that will be taken during this study are likely to contribute to a

  6. Biomechanical analysis of press-extension technique on degenerative lumbar with disc herniation and staggered facet joint.

    Science.gov (United States)

    Du, Hong-Gen; Liao, Sheng-Hui; Jiang, Zhong; Huang, Huan-Ming; Ning, Xi-Tao; Jiang, Neng-Yi; Pei, Jian-Wei; Huang, Qin; Wei, Hui

    2016-05-01

    This study investigates the effect of a new Chinese massage technique named "press-extension" on degenerative lumbar with disc herniation and facet joint dislocation, and provides a biomechanical explanation of this massage technique. Self-developed biomechanical software was used to establish a normal L1-S1 lumbar 3D FE model, which integrated the spine CT and MRI data-based anatomical structure. Then graphic technique is utilized to build a degenerative lumbar FE model with disc herniation and facet joint dislocation. According to the actual press-extension experiments, mechanic parameters are collected to set boundary condition for FE analysis. The result demonstrated that press-extension techniques bring the annuli fibrosi obvious induction effect, making the central nucleus pulposus forward close, increasing the pressure in front part. Study concludes that finite element modelling for lumbar spine is suitable for the analysis of press-extension technique impact on lumbar intervertebral disc biomechanics, to provide the basis for the disease mechanism of intervertebral disc herniation using press-extension technique. PMID:27275119

  7. The evolution of articular cartilage imaging and its impact on clinical practice

    International Nuclear Information System (INIS)

    Over the past four decades, articular cartilage imaging has developed rapidly. Imaging now plays a critical role not only in clinical practice and therapeutic decisions but also in the basic research probing our understanding of cartilage physiology and biomechanics. (orig.)

  8. Pulsed carbon dioxide laser for cartilage vaporization and subchondral bone perforation in horses. Part I: Technique and clinical results.

    Science.gov (United States)

    Roth, J E; Nixon, A J; Gantz, V A; Meyer, D; Mohammed, H

    1991-01-01

    A carbon dioxide laser, used in a rapidly pulsed mode, was evaluated for intra-articular use in horses. Under arthroscopic guidance, a lensed 5 mm laser probe attached directly to a hand-held carbon dioxide laser was inserted into one intercarpal joint of eight horses. In four horses, a cartilage crater 1 cm in diameter was created to the level of the subchondral bone of the articular surface of the third carpal bone. In four horses, the laser was directed perpendicular to the articular surface of the third carpal bone and activated to penetrate the cartilage and subchondral bone. The intercarpal joint of the opposite carpus in each horse was subjected to arthroscopic examination and insertion of the laser probe for an equivalent time. The laser was not activated and these joints served as sham operated controls. The horses were evaluated clinically for 8 weeks, then euthanatized, and the joints were examined radiographically, grossly, and histologically. Pulsed carbon dioxide laser vaporized cartilage readily but penetrated bone poorly. Cartilage vaporization resulted in no greater swelling, heat, pain on flexion, lameness, or synovial fluid reaction than the sham procedure. Laser drilling resulted in a shallow, charred hole with a tenacious carbon residue, and in combination with the thermal damage to deeper bone, resulted in increased swelling, mild lameness and a low-grade, but persistent synovitis. The carbon dioxide laser is a useful intra-articular instrument for removal of cartilage and has potential application in inaccessible regions of diarthrodial joints. It does not penetrate bone sufficiently to have application in subchondral drilling. PMID:1853552

  9. The Emerging Role of Mindfulness Meditation as Effective Self-Management Strategy, Part 1: Clinical Implications for Depression, Post-Traumatic Stress Disorder, and Anxiety.

    Science.gov (United States)

    Khusid, Marina A; Vythilingam, Meena

    2016-09-01

    Mindfulness-based interventions (MBIs) have been increasingly utilized in the management of mental health conditions. This first review of a two-part series evaluates the efficacy, mechanism, and safety of mindfulness meditation for mental health conditions frequently seen after return from deployment. Standard databases were searched until August 4, 2015. 52 systematic reviews and randomized clinical trials were included. The Strength of Recommendation (SOR) Taxonomy was used to assess the quality of individual studies and to rate the strength of evidence for each clinical condition. Adjunctive mindfulness-based cognitive therapy is effective for decreasing symptom severity during current depressive episode, and for reducing relapse rate in recovered patients during maintenance phase of depression management (SOR moderate [SOR B]). Adjunctive mindfulness-based stress reduction is effective for improving symptoms, mental health-related quality of life, and mindfulness in veterans with combat post-traumatic stress disorder (PTSD) (SOR B). Currently, there is no sufficient data to recommend MBIs for generalized anxiety disorder (SOR B). MBIs are safe, portable, cost-effective, and can be recommended as an adjunct to standard care or self-management strategy for major depressive disorder and PTSD. Future large, well-designed randomized clinical trials in service members and veterans can help plan for the anticipated increase in demand for behavioral health services. PMID:27612338

  10. Kick, Glide, Pole! Cross-Country Skiing Fun (Part II)

    Science.gov (United States)

    Duoos, Bridget A.

    2012-01-01

    Part I of Kick, Glide, Pole! Cross-Country Skiing Fun, which was published in last issue, discussed how to select cross-country ski equipment, dress for the activity and the biomechanics of the diagonal stride. Part II focuses on teaching the diagonal stride technique and begins with a progression of indoor activities. Incorporating this fun,…

  11. The role of estrogens at men. Part 2. Private clinical endocrinology and pathophysiology of estrogens at men

    Directory of Open Access Journals (Sweden)

    I. A. Tyuzikov

    2015-04-01

    Full Text Available Until now, estrogens are traditionally considered primarily as key hormones that perform critical functions in females, however, their role in males is not less important, although it remains understudied. However, a deep understanding of male physiology and endocrinology, it is imperative to solve practical problems of gender pathogenetic therapy of men,s diseases, is impossible today without taking into account the key role of testosterone in males, and without rethinking the role of estrogens, 80 % of which in males formed as a result of testosterone aromatisation. Thus, the violation of the synthesis and metabolism of testosterone in men naturally lead to disorder of the synthesis and metabolism of estrogen, which allows to express the idea that without estrogens, testosterone alone can not provide the entire range of the male body physiological effects. The second part of the literature review highlights exactly the Private Endocrinology and Pathophysiology of estrogens in men, which prove this assertion. The most important systems in which the regulation of the primary role of estrogens is presented in both sexes are central nervous system and bones, and possible mechanisms of these pathophysiological effects of estrogen in males are reviewed in detail. In addition, issues of influence of estrogens at the state of the male breast (gynecomastia, and shows close interaction of estrogens and androgens in providing function of male reproductive and cardiovascular systems. Today we know that the pathogenesis of such common disease in men as benign prostatic hyperplasia (BPH, is closely associated with the pathophysiology of both androgens and estrogens, so mechanisms of estrogens participation in the processes of prostatic proliferation (BPH are examined in detail in this review. Urgent problem of men,s health is prostate cancer, which has a hormonal nature, so current data available on the hormonal mechanisms of this disease with estrogens are

  12. Lithium: updated human knowledge using an evidence-based approach. Part II: Clinical pharmacology and therapeutic monitoring.

    Science.gov (United States)

    Grandjean, Etienne Marc; Aubry, Jean-Michel

    2009-01-01

    After a single dose, lithium, usually given as carbonate, reaches a peak plasma concentration at 1.0-2.0 hours for standard-release dosage forms, and 4-5 hours for sustained-release forms. Its bioavailability is 80-100%, its total clearance 10-40 mL/min and its elimination half-life is 18-36 hours. Use of the sustained-release formulation results in 30-50% reductions in peak plasma concentrations without major changes in the area under the plasma concentration curve. Lithium distribution to the brain, evaluated using 7Li magnetic resonance spectroscopy, showed brain concentrations to be approximately half those in serum, occasionally increasing to 75-80%. Brain concentrations were weakly correlated with serum concentrations. Lithium is almost exclusively excreted via the kidney as a free ion and lithium clearance is considered to decrease with aging. No gender- or race-related differences in kinetics have been demonstrated. Renal insufficiency is associated with a considerable reduction in renal clearance of lithium and is considered a contraindication to its use, especially if a sodium-poor diet is required. During the last months of pregnancy, lithium clearance increases by 30-50% as a result of an increase in glomerular filtration rate. Lithium also passes freely from maternal plasma into breast milk. Numerous kinetic interactions have been described for lithium, usually involving a decrease in the drug's clearance and therefore increasing its potential toxicity. Clinical pharmacology studies performed in healthy volunteers have investigated a possible effect of lithium on cognitive functions. Most of these studies reported a slight, negative effect on vigilance, alertness, learning and short-term memory after long-term administration only. Because of the narrow therapeutic range of lithium, therapeutic monitoring is the basis for optimal use and administration of this drug. Lithium dosages should be adjusted on the basis of the serum concentration drawn

  13. Composition of The Knee Index, a novel three-dimensional biomechanical index for knee joint load, in subjects with mild to moderate knee osteoarthritis

    DEFF Research Database (Denmark)

    Clausen, Brian; Andriacchi, Tom; Nielsen, Dennis Brandborg;

    Background Knee joint load is an important factor associated with progression of knee osteoarthritis. To provide an overall understanding of knee joint loading, the Knee Index (KI) has been developed to include moments from all three planes (frontal, sagittal and transversal). However, before KI is...... used in clinical trials a biomechanical analysis identifying the respective contributions of the knee moments derived from the three planes is needed. Aim The purpose of this study was therefor to investigate how the frontal, sagittal and transversal moments contribute to KI, a novel biomechanical...... index of joint load for the knee, in patients with mild to moderate knee osteoarthritis. Methods The contribution of frontal, sagittal and transversal plane knee moments to KI was investigated in 24 subjects (13 women, age: 58 ± 7.6 years, BMI: 27.1 ± 3.0) with clinically diagnosed mild to moderate knee...

  14. Biomechanical analysis of the swim-start: a review.

    Science.gov (United States)

    Vantorre, Julien; Chollet, Didier; Seifert, Ludovic

    2014-05-01

    This review updates the swim-start state of the art from a biomechanical standpoint. We review the contribution of the swim-start to overall swimming performance, the effects of various swim-start strategies, and skill effects across the range of swim-start strategies identified in the literature. The main objective is to determine the techniques to focus on in swimming training in the contemporary context of the sport. The phases leading to key temporal events of the swim-start, like water entry, require adaptations to the swimmer's chosen technique over the course of a performance; we thus define the swim-start as the moment when preparation for take-off begins to the moment when the swimming pattern begins. A secondary objective is to determine the role of adaptive variability as it emerges during the swim-start. Variability is contextualized as having a functional role and operating across multiple levels of analysis: inter-subject (expert versus non-expert), inter-trial or intra-subject (through repetitions of the same movement), and inter-preference (preferred versus non-preferred technique). Regarding skill effects, we assume that swim-start expertise is distinct from swim stroke expertise. Highly skilled swim-starts are distinguished in terms of several factors: reaction time from the start signal to the impulse on the block, including the control and regulation of foot force and foot orientation during take-off; appropriate amount of glide time before leg kicking commences; effective transition from leg kicking to break-out of full swimming with arm stroking; overall maximal leg and arm propulsion and minimal water resistance; and minimized energy expenditure through streamlined body position. Swimmers who are less expert at the swim-start spend more time in this phase and would benefit from training designed to reduce: (i) the time between reaction to the start signal and impulse on the block, and (ii) the time in transition (i.e., between gliding and leg

  15. Framework and Bio-Mechanical Model for a Per-Operative Image-Guided Neuronavigator Including 'Brain-Shift' Compensation

    CERN Document Server

    Bucki, M; Bucki, Marek; Payan, Yohan

    2006-01-01

    In this paper we present a methodology to adress the problem of brain tissue deformation referred to as "brainshift". This deformation occurs throughout a neurosurgery intervention and strongly alters the accuracy of the neuronavigation systems used to date in clinical routine which rely solely on preoperative patient imaging to locate the surgical target, such as a tumour or a functional area. After a general description of the framework of our intraoperative image-guided system, we propose a biomechanical model of the brain which can take into account interactively such deformations as well as surgical procedures that modify the brain structure, like tumour or tissue resection.

  16. Biomechanical Evaluation of Plate Versus Lag Screw Only Fixation of Distal Fibula Fractures.

    Science.gov (United States)

    Misaghi, Amirhossein; Doan, Josh; Bastrom, Tracey; Pennock, Andrew T

    2015-01-01

    Traditional fixation of unstable Orthopaedic Trauma Association type B/C ankle fractures consists of a lag screw and a lateral or posterolateral neutralization plate. Several studies have demonstrated the clinical success of lag screw only fixation; however, to date no biomechanical comparison of the different constructs has been performed. The purpose of the present study was to evaluate the biomechanical strength of these different constructs. Osteotomies were created in 40 Sawbones(®) distal fibulas and reduced using 1 bicortical 3.5-mm stainless steel lag screw, 2 bicortical 3.5-mm lag screws, 3 bicortical 3.5-mm lag screws, or a single 3.5-mm lag screw coupled with a stainless steel neutralization plate with 3 proximal cortical and 3 distal cancellous screws. The constructs were tested to determine the stiffness in lateral bending and rotation and failure torque. No significant differences in lateral bending or rotational stiffness were detected between the osteotomies fixed with 3 lag screws and a plate. Constructs fixed with 1 lag screw were weaker for both lateral bending and rotational stiffness. Osteotomies fixed with 2 lag screws were weaker in lateral bending only. No significant differences were found in the failure torque. Compared with lag screw only fixation, plate fixation requires larger incisions and increased costs and is more likely to require follow-up surgery. Despite the published clinical success of treating simple Orthopaedic Trauma Association B/C fractures with lag screw only fixation, many surgeons still have concerns about stability. For noncomminuted, long oblique distal fibula fractures, lag screw only fixation techniques offer construct stiffness similar to that of traditional plate and lag screw fixation. PMID:25990534

  17. Automatized Patient-Specific Methodology for Numerical Determination of Biomechanical Corneal Response.

    Science.gov (United States)

    Ariza-Gracia, M Á; Zurita, J; Piñero, D P; Calvo, B; Rodríguez-Matas, J F

    2016-05-01

    This work presents a novel methodology for building a three-dimensional patient-specific eyeball model suitable for performing a fully automatic finite element (FE) analysis of the corneal biomechanics. The reconstruction algorithm fits and smooths the patient's corneal surfaces obtained in clinic with corneal topographers and creates an FE mesh for the simulation. The patient's corneal elevation and pachymetry data is kept where available, to account for all corneal geometric features (central corneal thickness-CCT and curvature). Subsequently, an iterative free-stress algorithm including a fiber's pull-back is applied to incorporate the pre-stress field to the model. A convergence analysis of the mesh and a sensitivity analysis of the parameters involved in the numerical response is also addressed to determine the most influential features of the FE model. As a final step, the methodology is applied on the simulation of a general non-commercial non-contact tonometry diagnostic test over a large set of 130 patients-53 healthy, 63 keratoconic (KTC) and 14 post-LASIK surgery eyes. Results show the influence of the CCT, intraocular pressure (IOP) and fibers (87%) on the numerical corneal displacement [Formula: see text] the good agreement of the [Formula: see text] with clinical results, and the importance of considering the corneal pre-stress in the FE analysis. The potential and flexibility of the methodology can help improve understanding of the eye biomechanics, to help to plan surgeries, or to interpret the results of new diagnosis tools (i.e., non-contact tonometers). PMID:26307330

  18. Functional Ability Improved in Essential Tremor by IncobotulinumtoxinA Injections Using Kinematically Determined Biomechanical Patterns – A New Future

    Science.gov (United States)

    Samotus, Olivia; Rahimi, Fariborz; Lee, Jack; Jog, Mandar

    2016-01-01

    Objective Effective treatment for functional disability caused by essential tremor is a significant unmet need faced by many clinicians today. Current literature regarding focal therapy by botulinum toxin type A (BoNT-A) injections uses fixed dosing regimens, which cannot be individualized, provides only limited functional benefit and unacceptable muscle weakness commonly occurs. This 38-week open label study, the longest to-date, demonstrates how kinematic technology addressed all these issues by guiding muscle selection. Method Participants (n = 24) were assessed at weeks 0, 6, 16, 22, 32, and 38 and injected with incobotulinumtoxinA at weeks 0, 16, and 32. Clinical assessments including UPDRS tremor items, Fahn-Tolosa-Marin (FTM) tremor rating scale assessing tremor severity, writing and functional ability, quality of life questionnaire (QUEST) and objective kinematic assessments were completed at every visit. Participants performed two postural and two weight-bearing scripted tasks with motion sensors placed over the wrist, elbow and shoulder joints. These sensors captured angular tremor amplitude (RMS units) and acceleration joint motion that was segmented into directional components: flexion-extension (F/E), pronation-supination and radial-ulnar at the wrist, F/E at the elbow, and F/E and adduction-abduction at the shoulder. Injection parameters were determined using kinematics, followed by the clinician’s determination of which muscles would contribute to the specific upper limb tremor biomechanics and dosing per participant. Results Multi-joint biomechanical recordings allowed individualized muscle selection and showed significant improvement in whole-arm function, FTM parts A-C scores, at week 6 which continued throughout the study. By week 38, the total FTM score statistically significantly reduced from 16.2±4.6 at week 0 to 9.5±6.3 (p<0.0005). UPDRS item 21 score rating action tremor was significantly reduced from 2.6±0.5 at week 0 to 1.6±1.1 (p

  19. Biomechanical comparison of lumbar spine instability between laminectomy and bilateral laminotomy for spinal stenosis syndrome – an experimental study in porcine model

    OpenAIRE

    Chen Lih-Huei; Chen Weng-Pin; Hsieh Pang-Hsing; Tai Ching-Lung; Chen Wen-Jer; Lai Po-Liang

    2008-01-01

    Abstract Background The association of lumbar spine instability between laminectomy and laminotomy has been clinically studied, but the corresponding in vitro biomechanical studies have not been reported. We investigated the hypothesis that the integrity of the posterior complex (spinous process-interspinous ligament-spinous process) plays an important role on the postoperative spinal stability in decompressive surgery. Methods Eight porcine lumbar spine specimens were studied. Each specimen ...

  20. Biomechanical Modeling of the Human Heart - Modeling of the Ventricles, the Atria and the Pericardium and the Inverse Problem of Cardiac Mechanics

    OpenAIRE

    Fritz, Thomas

    2015-01-01

    A biomechanical simulation framework has been developed which allows to simulate the contraction of the whole human heart. Further, an inverse solving algorithm has been developed, which works in an opposite manner and allows to reconstruct the active tension distribution from provided data of the motion of the heart surfaces, which can for example be extracted from medical imaging data. This allows for a personalization of the model based on clinical data.

  1. American society of clinical oncology update on the role of bisphosphonates and bone health issues in women with breast cancer Part II. Bisphosphonates in the adjuvant therapy of breast cancer

    Directory of Open Access Journals (Sweden)

    I. V. Vysotskaya

    2014-09-01

    Full Text Available American society of clinical oncology update on the roleof bisphosphonates and bone health issues in women with breast cancer Part II. Bisphosphonates in the adjuvant therapy of breast cancer

  2. The Biomechanical Testing for the Assessment of Bone Quality in an Experimental Model of Chronic Kidney Disease.

    Science.gov (United States)

    Oksztulska-Kolanek, Ewa; Znorko, Beata; Michałowska, Małgorzata; Pawlak, Krystyna

    2016-01-01

    Mineral metabolism disturbances are common in chronic kidney disease (CKD) and have been classified as a new clinical entity, also known as CKD-mineral and bone disorders (CKD-MBD). A decrease in the bone strength, whose clinical manifestation is a tendency for fracture, has been recognized as an important component of CKD-MBD. Because of ethical issues, measurements of the bone strength in the human body are usually limited to noninvasive techniques, such as radiography, dual-energy X-ray absorptiometry and the assays of bone turnover biomarkers. However, it has been postulated recently that the evidence concerning bone strength based solely on the determination of the bone quantity may be insufficient and that bone quality should also be examined. In this regard, an animal model of CKD can represent an experimental tool to test the effectiveness of new therapeutic strategies. Despite the many available methods that are used to diagnose metabolic bone disorders and predict fracture risk especially in small rodents with CKD, it turns out that the most appropriate are biomechanical tests, which can provide information about the structural and material properties of bone. The present review summarizes and discusses the principles for carrying out selected biomechanical tests (3-point bending test and compression test) and their application in clinical practice. PMID:26680019

  3. 3D printed guides for controlled alignment in biomechanics tests.

    Science.gov (United States)

    Verstraete, Matthias A; Willemot, Laurent; Van Onsem, Stefaan; Stevens, Cyriëlle; Arnout, Nele; Victor, Jan

    2016-02-01

    The bone-machine interface is a vital first step for biomechanical testing. It remains challenging to restore the original alignment of the specimen with respect to the test setup. To overcome this issue, we developed a methodology based on virtual planning and 3D printing. In this paper, the methodology is outlined and a proof of concept is presented based on a series of cadaveric tests performed on our knee simulator. The tests described in this paper reached an accuracy within 3-4° and 3-4mm with respect to the virtual planning. It is however the authors' belief that the method has the potential to achieve an accuracy within one degree and one millimeter. Therefore, this approach can aid in reducing the imprecisions in biomechanical tests (e.g. knee simulator tests for evaluating knee kinematics) and improve the consistency of the bone-machine interface. PMID:26810696

  4. Valgus torque in youth baseball pitchers: A biomechanical study.

    Science.gov (United States)

    Sabick, Michelle B; Torry, Michael R; Lawton, Richard L; Hawkins, Richard J

    2004-01-01

    The purpose of this study was to determine the biomechanical and anthropometric factors contributing to elbow valgus torque during pitching. Video data of 14 youth pitchers throwing fastballs were used to calculate shoulder and elbow kinematics and kinetics. Peak elbow valgus torque averaged 18 Nm and occurred just before maximal shoulder external rotation. The magnitude of valgus torque was most closely correlated with the thrower's weight. When subject weight and height were controlled for, maximum shoulder abduction torque and maximum shoulder internal rotation torque were most strongly associated with elbow valgus torque, accounting for 85% of its variance (P <.001). When only kinematic variables were considered, maximum shoulder external rotation accounted for 33% of the variance in valgus torque. Given that the biomechanical variables correlated with peak valgus torque are not easily modifiable, limiting the number of innings pitched is likely the best way to reduce elbow injury in youth pitchers. PMID:15111908

  5. Smart Materials in Structural Health Monitoring, Control and Biomechanics

    CERN Document Server

    Soh, Chee-Kiong; Bhalla, Suresh

    2012-01-01

    "Smart Materials in Structural Health Monitoring, Control and Biomechanics" presents the latest developments in structural health monitoring, vibration control and biomechanics using smart materials. The book mainly focuses on piezoelectric, fibre optic and ionic polymer metal composite materials. It introduces concepts from the very basics and leads to advanced modelling (analytical/ numerical), practical aspects (including software/ hardware issues) and case studies spanning civil, mechanical and aerospace structures, including bridges, rocks and underground structures. This book is intended for practicing engineers, researchers from academic and R&D institutions and postgraduate students in the fields of smart materials and structures, structural health monitoring, vibration control and biomedical engineering. Professor Chee-Kiong Soh and Associate Professor Yaowen Yang both work at the School of Civil and Environmental Engineering, Nanyang Technological University, Singapore. Dr. Suresh Bhalla is an A...

  6. Biomechanical bases of rehabilitation of children with cerebral palsy

    Science.gov (United States)

    Davlet'yarova, K. V.; Korshunov, S. D.; Kapilevich, L. V.

    2015-11-01

    Biomechanical analysis and the study results of children's with cerebral palsy (CP) muscles bioelectrical activity while walking on a flat surface are represented. Increased flexion in the hip and shoulder joints and extension in the elbow joint in children with cerebral palsy were observed, with the movement of the lower limbs had less smooth character in comparison with the control group. Herewith, the oscillation amplitude was significantly increased, and the frequency in the m. gastrocnemius and m. lateralis was decreased. It was shown, that the dynamic stereotype of walking in children with cerebral palsy was characterized by excessive involvement of m. gastrocnemius and m.latissimus dorsi in locomotion. Thus, resulting biomechanical and bioelectrical parameters of walking should be considered in the rehabilitation programs development.

  7. Hand Posture Prediction using Neural Networks within a Biomechanical Model

    Directory of Open Access Journals (Sweden)

    Marta C. Mora

    2012-10-01

    Full Text Available This paper proposes the use of artificial neural networks (ANNs in the framework of a biomechanical hand model for grasping. ANNs enhance the model capabilities as they substitute estimated data for the experimental inputs required by the grasping algorithm used. These inputs are the tentative grasping posture and the most open posture during grasping. As a consequence, more realistic grasping postures are predicted by the grasping algorithm, along with the contact information required by\tthe dynamic biomechanical model (contact points and normals. Several neural network architectures are tested and compared in terms of prediction errors, leading to encouraging results. The performance of the overall proposal is also shown through simulation, where a grasping experiment is replicated and compared to the real grasping data collected by a data glove device.

  8. Scapholunate Interosseous Ligament Anatomy and Biomechanics.

    Science.gov (United States)

    Rajan, Prashant V; Day, Charles S

    2015-08-01

    Injury to the scapholunate interosseous ligament is one of the most common causes of carpal instability and can impart considerable compromise to the patient's hand function. However, the management of scapholunate ligament injuries remains a dynamic concept, especially with regard to the multitude of options and techniques that exist for its surgical treatment. We present a thorough review of scapholunate anatomy and morphology, and the role of the scapholunate articulations in the kinetics and pathomechanics of wrist instability. We also review the current literature on the biomechanical properties of the scapholunate ligament and its subcomponents. A sound understanding of the anatomy and biomechanics of the scapholunate ligament can clarify its instability and may better orient current reconstructive procedures or pioneer better future techniques. PMID:26143029

  9. The biomechanics of kicking in soccer: a review.

    Science.gov (United States)

    Lees, A; Asai, T; Andersen, T B; Nunome, H; Sterzing, T

    2010-06-01

    Kicking is the defining action of soccer, so it is appropriate to review the scientific work that provides a basis of our understanding of this skill. The focus of this review is biomechanical in nature and builds on and extends previous reviews and overviews. While much is known about the biomechanics of the kicking leg, there are several other aspects of the kick that have been the subject of recent exploration. Researchers have widened their interest to consider the kick beginning from the way a player approaches the ball to the end of ball flight, the point that determines the success of the kick. This interest has encapsulated characteristics of overall technique and the influences of the upper body, support leg and pelvis on the kicking action, foot-ball impact and the influences of footwear and soccer balls, ball launch characteristics and corresponding flight of the ball. This review evaluates these and attempts to provide direction for future research. PMID:20509089

  10. Meshless methods in biomechanics bone tissue remodelling analysis

    CERN Document Server

    Belinha, Jorge

    2014-01-01

    This book presents the complete formulation of a new advanced discretization meshless technique: the Natural Neighbour Radial Point Interpolation Method (NNRPIM). In addition, two of the most popular meshless methods, the EFGM and the RPIM, are fully presented. Being a truly meshless method, the major advantages of the NNRPIM over the FEM, and other meshless methods, are the remeshing flexibility and the higher accuracy of the obtained variable field. Using the natural neighbour concept, the NNRPIM permits to determine organically the influence-domain, resembling the cellulae natural behaviour. This innovation permits the analysis of convex boundaries and extremely irregular meshes, which is an advantage in the biomechanical analysis, with no extra computational effort associated.   This volume shows how to extend the NNRPIM to the bone tissue remodelling analysis, expecting to contribute with new numerical tools and strategies in order to permit a more efficient numerical biomechanical analysis.

  11. Biomechanical tactics of chiral growth in emergent aquatic macrophytes

    Science.gov (United States)

    Zhao, Zi-Long; Zhao, Hong-Ping; Li, Bing-Wei; Nie, Ben-Dian; Feng, Xi-Qiao; Gao, Huajian

    2015-07-01

    Through natural selection, many plant organs have evolved optimal morphologies at different length scales. However, the biomechanical strategies for different plant species to optimize their organ structures remain unclear. Here, we investigate several species of aquatic macrophytes living in the same natural environment but adopting distinctly different twisting chiral morphologies. To reveal the principle of chiral growth in these plants, we performed systematic observations and measurements of morphologies, multiscale structures, and mechanical properties of their slender emergent stalks or leaves. Theoretical modeling of pre-twisted beams in bending and buckling indicates that the different growth tactics of the plants can be strongly correlated with their biomechanical functions. It is shown that the twisting chirality of aquatic macrophytes can significantly improve their survivability against failure under both internal and external loads. The theoretical predictions for different chiral configurations are in excellent agreement with experimental measurements.

  12. Derivation, simulation and validation of poroelastic models in dental biomechanics

    OpenAIRE

    Favino, Marco; Krause, Rolf

    2015-01-01

    Poroelasticity and mechanics of growth are playing an increasingly relevant role in biomechanics. This work is a self- contained and holistic presentation of the modeling and simulation of non-linear poroelasticity with and without growth inhomogeneities. Balance laws of poroelasticity are derived in Cartesian coordinates. These allow to write the governing equations in a form that is general but also readily implementable. Closure relations are formally derived from the study of dissipati...

  13. Biomechanical simulation of thorax deformation using finite element approach

    OpenAIRE

    Zhang, Guangzhi; Chen, Xian; Ohgi, Junji; Miura, Toshiro; Nakamoto, Akira; Matsumura, Chikanori; Sugiura, Seiryo; Hisada, Toshiaki

    2016-01-01

    Background The biomechanical simulation of the human respiratory system is expected to be a useful tool for the diagnosis and treatment of respiratory diseases. Because the deformation of the thorax significantly influences airflow in the lungs, we focused on simulating the thorax deformation by introducing contraction of the intercostal muscles and diaphragm, which are the main muscles responsible for the thorax deformation during breathing. Methods We constructed a finite element model of t...

  14. Biomechanical analysis of the camelid cervical intervertebral disc

    OpenAIRE

    Dean K. Stolworthy; R. Amy Fullwood; Tyler M. Merrell; Bridgewater, Laura C.; Anton E. Bowden

    2015-01-01

    Chronic low back pain (LBP) is a prevalent global problem, which is often correlated with degenerative disc disease. The development and use of good, relevant animal models of the spine may improve treatment options for this condition. While no animal model is capable of reproducing the exact biology, anatomy, and biomechanics of the human spine, the quality of a particular animal model increases with the number of shared characteristics that are relevant to the human condition. The purpose o...

  15. Biomechanical evaluation of an expansive pedicle screw in calf vertebrae

    OpenAIRE

    Lei, Wei; Wu, Zixiang

    2005-01-01

    The main objective of the present study is to evaluate biomechanically a newly designed expansive pedicle screw (EPS) using fresh pedicles from calf lumber vertebrae in comparison with conventional pedicle screws, (CDH) CD Horizon, Universal Spine System pedicle screw (USS) and Tenor (Sofamor Denek). Pull-out and turning-back tests were performed on these pedicle screws to compare their holding strength. Additionally, revision tests were undertaken to evaluate the mechanical properties of EPS...

  16. A Microfluidic Platform for Profiling Biomechanical Properties of Bacteria

    OpenAIRE

    Sun, Xuanhao; Weinlandt, William D; Patel, Harsh; WU, Mingming; Hernandez, Christopher J.

    2014-01-01

    The ability to resist mechanical forces is necessary for the survival and division of bacteria and has traditionally been probed using specialized, low-throughput techniques such as atomic force microscopy and optical tweezers. Here we demonstrate a microfluidic technique to profile the stiffness of individual bacteria and populations of bacteria. The approach is similar to micropipette aspiration used to characterize the biomechanical performance of eukaryotic cells. However, the small size ...

  17. Application of optimal control to a biomechanics model

    OpenAIRE

    Krasovskii, A.

    2015-01-01

    A model of sport biomechanics describing short-distance running (sprinting) is developed by applying methods of optimal control. In the considered model, the motion of a sportsman is described by a second-order ordinary differential equation. Two interconnected optimal control problems are formulated and solved: the minimum energy and time-optimal control problems. Based on the comparison with real data, it is shown that the proposed approach to sprint modeling provides realistic results.

  18. Biomechanical considerations on tooth-implant supported fixed partial dentures

    OpenAIRE

    Michalakis, Konstantinos X.; Calvani, Pasquale; Hirayama, Hiroshi

    2012-01-01

    This article discusses the connection of teeth to implants, in order to restore partial edentulism. The main problem arising from this connection is tooth intrusion, which can occur in up to 7.3% of the cases. The justification of this complication is being attempted through the perspective of biomechanics of the involved anatomical structures, that is, the periodontal ligament and the bone, as well as that of the teeth- and implant-supported fixed partial dentures.

  19. Multiscale computer modeling in biomechanics and biomedical engineering

    CERN Document Server

    2013-01-01

    This book reviews the state-of-the-art in multiscale computer modeling, in terms of both accomplishments and challenges. The information in the book is particularly useful for biomedical engineers, medical physicists and researchers in systems biology, mathematical biology, micro-biomechanics and biomaterials who are interested in how to bridge between traditional biomedical engineering work at the organ and tissue scales, and the newer arenas of cellular and molecular bioengineering.

  20. Corneal Structure and Biomechanics in Collagen Vascular Diseases

    OpenAIRE

    Colaço, Maria Luisa; Franco, Mónica; Pinto, Rita; Maia Sêco, José

    2015-01-01

    Purpose: The purpose of this study was to evaluate corneal biomechanics and structure in asymptomatic individuals with Collagen Vascular Diseases (CVD), and compare with an age- -matched control group. Methods: In this prospective study 23 patients with the diagnosis of CVD (46 eyes) and 17 healthy age and gender-matched controls (34 eyes) underwent Ocular Response Analyzer and Specular Microscopy measurements. CH and CRF were recorded for each eye using the ORA, pachymetry and endothelial ce...

  1. Biomechanical models to simulate consequences of maxillofacial surgery

    OpenAIRE

    Payan, Yohan; Chabanas, Matthieu; Pelorson, Xavier; Vilain, Coriandre; Levy, Patrick; Luboz, Vincent; Perrier, Pascal

    2002-01-01

    This paper presents the biomechanical finite element models that have been developed in the framework of the computer-assisted maxillofacial surgery. After a brief overview of the continuous elastic modelling method, two models are introduced and their use for computer-assisted applications discussed. The first model deals with orthognathic surgery and aims at predicting the facial consequences of maxillary and mandibular osteotomies. For this, a generic three-dimensional model of the face is...

  2. On seed physiology, biomechanics and plant phenology in Eragrostis tef

    OpenAIRE

    Delden, van, J.

    2011-01-01

    • Key words: Teff (Eragrostis tef (Zuccagni) Trotter), germination, temperature, model, leaf appearance, phyllochron, development rate, lodging, biomechanics, safety factor, flowering, heading, day length, photoperiod. • Background Teff (Eragrostis tef (Zuccagni) Trotter) is a C4 annual grass species (Poaceae) originating from Ethiopia. Teff cultivation in the Netherlands is thought to be economically feasible because teff grains and flour do not contain gluten and are rich in iron....

  3. Absorbable scaphoid screw development: a comparative study on biomechanics

    OpenAIRE

    Xu, Yongqing

    2016-01-01

    Yi Wang, Muguo Song, Yongqing Xu, Xiaoqing He, YueLiang Zhu Department of Orthopedic Surgery, Kunming General Hospital, Chengdu Military Command, People’s Liberation Army, Kunming, Yunnan, People’s Republic of China Background: The scaphoid is critical for maintaining the stability and movement of the wrist joints. This study aimed to develop a new internal fixator absorbable scaphoid screw (ASS) for fixation of the scaphoid waist after fracture and to test the biomechan...

  4. Absorbable scaphoid screw development: a comparative study on biomechanics

    OpenAIRE

    Wang Y; Song MG; Xu YQ; He XQ; Zhu YL

    2016-01-01

    Yi Wang, Muguo Song, Yongqing Xu, Xiaoqing He, YueLiang Zhu Department of Orthopedic Surgery, Kunming General Hospital, Chengdu Military Command, People’s Liberation Army, Kunming, Yunnan, People’s Republic of China Background: The scaphoid is critical for maintaining the stability and movement of the wrist joints. This study aimed to develop a new internal fixator absorbable scaphoid screw (ASS) for fixation of the scaphoid waist after fracture and to test the biomechanical cha...

  5. Absorbable scaphoid screw development: a comparative study on biomechanics

    OpenAIRE

    Wang, Yi; Song, Muguo; Xu, Yongqing; He, Xiaoqing; Zhu, Yueliang

    2016-01-01

    Background The scaphoid is critical for maintaining the stability and movement of the wrist joints. This study aimed to develop a new internal fixator absorbable scaphoid screw (ASS) for fixation of the scaphoid waist after fracture and to test the biomechanical characteristics of ASS. Materials and methods An ASS was prepared using polylactic acids and designed based on scaphoid measurements and anatomic features. Twenty fractured scaphoid waist specimens were randomly divided into experimen...

  6. Biomechanical Evaluation of Capsulotomy and Capsular Repair in the Hip

    OpenAIRE

    Wuerz, Thomas H.; Song, Sang Hoon; Grzybowski, Jeffrey S.; Greenberg, Mitchell; Espinoza, Alejandro; Nho, Shane Jay

    2015-01-01

    Objectives: The use of hip arthroscopy has increased over recent years to treat various forms of hip pathologies including femoroacetabular impingement. While a capsulotomy facilitates adequate visualization and access for diagnostic and interventional purposes, the current literature remains divided over the use of routine capsular closure to address the iatrogenic instability that may be induced by an excessive or unclosed capsulotomy. The purpose of this biomechanical study was to determin...

  7. Biomechanical evaluation of fixation degree of fragments by periosteal osteosynthesis

    Directory of Open Access Journals (Sweden)

    Barabash Yu.A.

    2010-09-01

    Full Text Available Expansion of indications for surgery and plate osteosynthesis of long bones points to increased number of complications caused by instability of fragments, that can be associated in their turn with constructive features or iatrogenic factors. Insufficient rigidity of fragment fixation is due to incorrect technical treatment and wrong choice of fixator. Biomechanical parameters of periosteal fixation rigidity have been experimentally proved, depending on fixator lever

  8. Biomechanics of DNA structures visualized by 4D electron microscopy

    OpenAIRE

    Lorenz, Ulrich J.; Zewail, Ahmed H.

    2013-01-01

    We present a technique for in situ visualization of the biomechanics of DNA structural networks using 4D electron microscopy. Vibrational oscillations of the DNA structure are excited mechanically through a short burst of substrate vibrations triggered by a laser pulse. Subsequently, the motion is probed with electron pulses to observe the impulse response of the specimen in space and time. From the frequency and amplitude of the observed oscillations, we determine the normal modes and eig...

  9. Biomechanical properties of peripheral nerve after acellular treatment

    Institute of Scientific and Technical Information of China (English)

    MA Xin-long; SUN Xiao-lei; YANG Zhao; LI Xiu-lan; MA Jian-xiong; ZHANG Yang; YUAN Zhen-zhen

    2011-01-01

    Background Peripheral nerve injury causes a high rate of disability and a huge economic burden,and is currently one of the serious health problems in the world.The use of nerve grafts plays a vital role in repairing nerve defects.Acellular nerve grafts have been widely used in many experimental models as a peripheral nerve substitute.The purpose of this study was to test the biomechanical properties of acellular nerve grafts.Methods Thirty-four fresh sciatic nerves were obtained from 17 adult male Wistar rats (age of 3 months) and randomly assigned to 3 groups:normal control group,nerve segments underwent no treatment and were put in phosphate buffered saline (pH 7.4) and stored at 4℃ until further use; physical method group,nerve segments were frozen at -196℃ and then thawed at 37℃; and chemical method group,nerve segments were chemically extracted with the detergents Triton X-200,sulfobetaine-10 (SB-10) and sulfobetaine-16 (SB-16).After the acellularization process was completed,the structural changes of in the sciatic nerves in each group were observed by hematoxylin-eosin staining and field emission scanning electron microscopy,then biomechanical properties were tested using a mechanical apparatus (Endura TEC ELF 3200,Bose,Boston,USA).Results Hematoxylin-eosin staining and field emission scanning electron microscopy demonstrated that the effects of acellularization,demyelination,and integrity of nerve fiber tube of the chemical method were better than that of the physical method.Biomechanical testing showed that peripheral nerve grafts treated with the chemical method resulted in some decreased biomechanical properties (ultimate load,ultimate stress,ultimate strain,and mechanical work to fracture) compared with normal control nerves,but the differences were not statistically significant (P >0.05).Conclusion Nerve treated with the chemical method may be more appropriate for use in implantation than nerve treated with the physical method.

  10. Verification, Validation and Sensitivity Studies in Computational Biomechanics

    OpenAIRE

    Anderson, Andrew E.; Ellis, Benjamin J.; Weiss, Jeffrey A.

    2007-01-01

    Computational techniques and software for the analysis of problems in mechanics have naturally moved from their origins in the traditional engineering disciplines to the study of cell, tissue and organ biomechanics. Increasingly complex models have been developed to describe and predict the mechanical behavior of such biological systems. While the availability of advanced computational tools has led to exciting research advances in the field, the utility of these models is often the subject o...

  11. Structural and biomechanical basis of mitochondrial movement in eukaryotic cells

    OpenAIRE

    Wu M; Kalyanasundaram A; Zhu J

    2013-01-01

    Min Wu,1 Aruna Kalyanasundaram,2 Jie Zhu1 1Laboratory of Biomechanics and Engineering, Institute of Biophysics, College of Science, Northwest A&F University, Yangling, Shaanxi, People's Republic of China; 2College of Pharmacology, University of Illinois at Chicago, Chicago, IL, USA Abstract: Mitochondria serve as energy-producing organelles in eukaryotic cells. In addition to providing the energy supply for cells, the mitochondria are also involved in other processes, such as...

  12. Biomechanics and evolution of flight in stick insects

    OpenAIRE

    Zeng, Yu

    2013-01-01

    Many unresolved questions in animal flight evolution relate to the transition between flightless and volant forms. Functional analysis of transitional modes using anatomical intermediates may help to assess the biomechanical underpinnings to such transitional processes. The group of stick insects exhibits tremendous diversity in wing sizes, which is potentially correlated with selection gradient for wing size. This dissertation work uses stick insects as a model system to address the ecologic...

  13. Biomechanics of spontaneous overground walk-to-run transition

    OpenAIRE

    Segers, Veerle; Smet, de, M.D.; Caekenberghe, van, I.; Aerts, Peter; Clercq, de, Willem

    2013-01-01

    Abstract: The purpose of the present study was to describe the biomechanics of spontaneous walk-to-run transitions (WRTs) in humans. After minimal instructions, 17 physically active subjects performed WRTs on an instrumented runway, enabling measurement of speed, acceleration, spatiotemporal variables, ground reaction forces and 3D kinematics. The present study describes (1) the mechanical energy fluctuations of the body centre-of-mass (BCOM) as a reflection of the whole-body dynamics and (2)...

  14. Three-Dimensional Biomechanical Analysis of the Bovine Humerus

    OpenAIRE

    Bouza-Rodríguez, José Benito; Miramontes-Sequeiros, Luz Calia

    2014-01-01

    There are few reports on the biomechanical analysis of the animal humerus. In this study, a three-dimensional finite element model of the bovine humerus was created, and loaded with the physiological forces acting when the cow is falling or jumping (weight and impact forces). Subsequently the corresponding stress and strain distribution in the humerus for different inclined positions of bone was determined.The highest stress concentration occurred in the distal humeral diaphysis, both when on...

  15. Biomechanical model produced from light-activated dental composite resins: a holographic analysis

    Science.gov (United States)

    Pantelić, Dejan; Vasiljević, Darko; Blažić, Larisa; Savić-Šević, Svetlana; Murić, Branka; Nikolić, Marko

    2013-11-01

    Light-activated dental composites, commonly applied in dentistry, can be used as excellent material for producing biomechanical models. They can be cast in almost any shape in an appropriate silicone mold and quickly solidified by irradiation with light in the blue part of the spectrum. In that way, it is possible to obtain any number of nearly identical casts. The models can be used to study the behavior of arbitrary structure under mechanical loads. To test the technique, a simple mechanical model of the tooth with a mesio-occluso-distal cavity was manufactured. Composite resin restoration was placed inside the cavity and light cured. Real-time holographic interferometry was used to analyze the contraction of the composite resin and its effect on the surrounding material. The results obtained in the holographic experiment were in good agreement with those obtained using the finite element method.

  16. Biomechanical model produced from light-activated dental composite resins: a holographic analysis

    International Nuclear Information System (INIS)

    Light-activated dental composites, commonly applied in dentistry, can be used as excellent material for producing biomechanical models. They can be cast in almost any shape in an appropriate silicone mold and quickly solidified by irradiation with light in the blue part of the spectrum. In that way, it is possible to obtain any number of nearly identical casts. The models can be used to study the behavior of arbitrary structure under mechanical loads. To test the technique, a simple mechanical model of the tooth with a mesio–occluso–distal cavity was manufactured. Composite resin restoration was placed inside the cavity and light cured. Real-time holographic interferometry was used to analyze the contraction of the composite resin and its effect on the surrounding material. The results obtained in the holographic experiment were in good agreement with those obtained using the finite element method. (paper)

  17. The importance of carrying a backpack in the rehabilitation of osteoporotic patients (biomechanical analysis).

    Science.gov (United States)

    Wendlova, J

    2011-01-01

    Based on a simple biomechanical analysis available to physicians, the article recommends carrying a backpack regularly as a part of the complex rehabilitation of osteoporotic patients. Carrying a backpack in front or on the back is recommended to patients with uncomplicated osteoporosis, while carrying a backpack on the back only is recommended to patients with osteporotic vertebral fractures. The importance of carrying a backpack is based upon removing the muscular dysbalance of the trunk muscles and upon increasing the bone strength by compressive force acting upon the vertebrae and proximal femur and activating osteoblasts to enhance the process of osteoformation. The backpack load is differentiated--patients with vertebral fractures put a weight up to 1 kg into their backpacks, patients without vertebral fractures increase the load up to 2 kg (Fig. 2, Ref. 12). PMID:21452778

  18. Decreased trabecular bone biomechanical competence, apparent density, IGF-II and IGFBP-5 content in acromegaly

    DEFF Research Database (Denmark)

    Ueland, Thor; Ebbesen, Ebbe Nils; Thomsen, Jesper Skovhus;

    2002-01-01

    BACKGROUND: Earlier studies on the effect of excess growth hormone (GH) on trabecular bone have been conflicting. Since insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) in part mediate the effects of GH, the present study aimed to investigate trabecular bone composition of...... found in trabecular bone content of IGF-I, IGFBP-3, or osteocalcin. However, IGF-II and IGFBP-5 content was decreased (P < 0.001 and P < 0.05, respectively). CONCLUSIONS: The present study demonstrates reduced trabecular biomechanical competence and apparent density in acromegaly, supporting previous...... observations of an unfavourable effect of chronic excess GH on the axial skeleton. Furthermore, we demonstrate decreased trabecular bone content of IGF-II and IGFBP-5 in these patients. However, we found no direct causal relationship between trabecular bone density and bone content of IGF-system components....

  19. BIOMECHANICS OF FLIGHT PHASE WHEN RUNNING LONG JUMP FROM PLACE OF DIFFERENT QUALIFICATION SPORTSMEN

    Directory of Open Access Journals (Sweden)

    A. V. Razuvanova

    2015-12-01

    Full Text Available Biomechanical features of flight phase when running long jump from place of different qualification sportsmen were investigated by method of Motion Tracking. The obtained results showed that the effective control of body position during the phase of flight can improve the effectiveness of jump actions.. This control is performed by moving parts of the body – bending legs at the knee, extension in the hip joints, the joints of the spine, shoulder joints and, as a consequence, any additional torque, contributing to increase the range of the jumping. In untrained persons the effectiveness of the management body in flight is reduced due to weak coordination and a predominance of actions aimed at safe. All the patterns can be viewed as the result of formation of a particular movement pattern, based on the interaction of vestibular and statokinetic reflexes. 

  20. Biomechanical study athletes’ movement techniques in the hurdles (on example of phase of flight

    Directory of Open Access Journals (Sweden)

    Adashevskiy V.M.

    2014-07-01

    Full Text Available Purpose: To design a theoretical biomechanical model of athletes’ movement techniques in the hurdles and then check there movements on real athletes. Material : In the practical part of the study participated 10 smortsmen. Results : Showing the possibility of constructing a theoretical model of hurdling technique. The basis of constructing a model using the known approaches in theoretical mechanics. Shows the calculated and actual performance movement of the athlete. Conclusions : The developed model provides a good theoretical understanding of the interactions of individual elements of movement and the ability to simulate different situations and to determine the optimal values of the kinematic and dynamic characteristics of the movement of the athlete. The model allows the individual elements of motion correction directly in the process of training. When analyzing art movement should consider specific features of physical development and anthropometric characteristics of the athlete's body.

  1. Biomechanics of the Metalloceramic Bridge Prostheses at the Dental Row Lateral Department Small Defect Substitution

    Directory of Open Access Journals (Sweden)

    Zhulyov E.N.

    2009-12-01

    Full Text Available A method of mathematical simulation was used for prosthetics improvement of patients with the dental row lateral department small defects by combined bridge prostheses with a support on insets. Four types of the metalloceramic bridge prosthesis constructions were used at a study of a biomechanics in a system of ″bridge prosthesis—supporting teeth—periodontium—alveolar part of a jaw″. The investigation results have demonstrated that a distribution of elastic tensions is unfavorable and can cause complications in bridge prostheses with a mesial support on inset and a distal support in a form of artificial crown. It is recommended to use the bridge prostheses with a bilateral support on insets in the mesioocclusive and distal cavities and the prosthesis constructions with a mesial support in a form of artificial crown and a distal support in a form of inset for substitution of the dental row lateral department small defects.

  2. The diagnostic value of transabdominal sonography of the gastrointestinal tract, particularly in cases without clinical signs. Comparison with the endoscopic and radiological studies - part I

    International Nuclear Information System (INIS)

    Recent years have seen progress in transabdominal ultrasonography (TUS) of the stomach and intestine as a result of more exact evaluation of the wall stratification of these organs and the thickness and echogenicity of the layers, some of these caused by interface echo. These echoes are produced at a tissue interface, where the acoustic impedance changes between two tissues. An interface echo layer is different from a histological layer. With careful TUS of the stomach and intestines it is possible to diagnose lesions of these organs despite silent clinical symptoms. The material included 340 patients in whom lesions were detected by means of TUS: 88 cases of stomach lesions, 15 cases of small intestine lesions, 215 cases of large intestine lesions, and 22 cases of pendicitis. Endoscopic and histopathological examinations as well as 42 reliable radiological examinations of these patients were performed. The results of these examinations were subjected to statistical assessment. Of the 88 cases of stomach lesions detected by ultrasonography, 68 were confirmed by gastroscopy and 20 by reliable radiological double-contrast examination. In this group, 72 patients without clinical data and 16 patients with clinical symptoms of stomach pathology were examined. From these data it is evident that correct diagnoses were established using ultrasonography in 84% of the examined patients, whereas 16% of the results were false positive. Of the 16 cases of clinically suspected stomach lesions, the proportion of correct diagnoses established by means of ultrasonography constituted the greater part and amounted to 93% of the examined patients (15 patients). This fact perhaps demonstrates that the examining radiologist, who was made 'sensitive' by the clinician, searched more precisely for lesions and, above all, that the lesions TUS examinations of the stomach and small and large intestine have a high diagnostic value, and each abdominal cavity ultrasonography should include such

  3. Statistics in review. Part 2: generalised linear models, time-to-event and time-series analysis, evidence synthesis and clinical trials.

    Science.gov (United States)

    Moran, John L; Solomon, Patricia J

    2007-06-01

    In Part I, we reviewed graphical display and data summary, followed by a consideration of linear regression models. Generalised linear models, structured in terms of an exponential response distribution and link function, are now introduced, subsuming logistic and Poisson regression. Time-to-event ("survival") analysis is developed from basic principles of hazard rate, and survival, cumulative distribution and density functions. Semi-parametric (Cox) and parametric (accelerated failure time) regression models are contrasted. Time-series analysis is explicated in terms of trend, seasonal, and other cyclical and irregular components, and further illustrated by development of a classical Box-Jenkins ARMA (autoregressive moving average) model for monthly ICU-patient hospital mortality rates recorded over 11 years. Multilevel (random-effects) models and principles of meta-analysis are outlined, and the review concludes with a brief consideration of important statistical aspects of clinical trials: sample size determination, interim analysis and "early stopping". PMID:17536991

  4. Cell biomechanics and its applications in human disease diagnosis

    Science.gov (United States)

    Nematbakhsh, Yasaman; Lim, Chwee Teck

    2015-04-01

    Certain diseases are known to cause changes in the physical and biomechanical properties of cells. These include cancer, malaria, and sickle cell anemia among others. Typically, such physical property changes can result in several fold increases or decreases in cell stiffness, which are significant and can result in severe pathology and eventual catastrophic breakdown of the bodily functions. While there are developed biochemical and biological assays to detect the onset or presence of diseases, there is always a need to develop more rapid, precise, and sensitive methods to detect and diagnose diseases. Biomechanical property changes can play a significant role in this regard. As such, research into disease biomechanics can not only give us an in-depth knowledge of the mechanisms underlying disease progression, but can also serve as a powerful tool for detection and diagnosis. This article provides some insights into opportunities for how significant changes in cellular mechanical properties during onset or progression of a disease can be utilized as useful means for detection and diagnosis. We will also showcase several technologies that have already been developed to perform such detection and diagnosis.

  5. Biomechanical analysis of tibia – double threaded screw fixation

    Directory of Open Access Journals (Sweden)

    W. Walke

    2008-03-01

    Full Text Available Purpose: The aim of the work was determination of biomechanical characteristics of a tibia – double threaded screw system with the use of finite element method.Design/methodology/approach: Geometrical model of the tibia was worked out on the basis of data from computer tomography of real bone. Geometrical model of the double threaded screw was prepared in ANSYS v. 11. Meshing was realized with the use of SOLID95 elements, applied in analyses of volumes. The model was loaded with forces in the range F = 100-2000 N.Findings: Initial biomechanical analysis, carried out with the use of finite element method, showed usefulness of the analyzed form of the double threaded screw made of Ti6Al4V alloy in fractured tibia treatment.Research limitations/implications: Due to applied simplifications of the tibia – double threaded screw fixation model, the analysis results should be experimentally verified in laboratory conditions.Originality/value: The obtained biomechanical characteristics of the tibia – double threaded screw system (u = f(F, σmax = f(F are the basis for selection of degree of strain hardening of the applied metallic biomaterial and optimization of geometrical features of the analyzed form of implant. Appropriate selection of mechanical properties and geometrical features of the implant is the main factor determining a stability of the fixation.

  6. BIOMECHANIC EVALUATION OF CARPENTRY WORKERS IN THE DISTRITO FEDERAL, BRAZIL

    Directory of Open Access Journals (Sweden)

    Nilton Cesar Fiedler

    2010-08-01

    Full Text Available The aim of this study was the biomechanical assessment of carpentry woodworkers, located in Brasília, DF. It was filmed the profile of each worker during the performance of his activities in the carpentry and the forces involved in the work were assessed. The image of each woodworker was congealed to accomplish the measurement of articulation angles. The data were submitted to the software of posture analysis “Winowas” (OWAS Method and to the biomechanic model of posture prognosis and static forces, developed by Michigan University. The OWAS method showed that, for all machines and carpentries assessed, the worst posture occurred when the worker lifted and placed the pieces of wood on the floor and during the feeding in the smoother. The tridimensional biomechanic model registered the worst posture in different phases of the work cycle. In the first one, there were problems in all articulations, except the hips, when placing the pieces on the floor from the smoother. In the second one, there were problems in all articulations, except the elbows and the L5-S1 column disc, by feeding the surface planer. The third one, the ankles were the most injured when feeding the smoother, the surface planer, the circular saw and the band saw. According to the results, the woodworkers should try to eliminate the constant work standing upright, use auxiliary machinery to handle pieces of wood, reduce the load during feeding the machines and improve postures.

  7. Biomechanical effects of dissecting flexor carpi ulnaris.

    Science.gov (United States)

    Kreulen, M; Smeulders, M J C; Hage, J J; Huijing, P A

    2003-08-01

    Our aim was to determine whether the length and function of the flexor carpi ulnaris muscle were affected by separating it from its soft tissue connections. We measured the length of flexor carpi ulnaris before and after its dissection in ten patients with cerebral palsy. After tenotomy, tetanic contraction shortened the muscle by a mean of 8 mm. Subsequent dissection to separate it from all soft tissue connections, resulted in a further mean shortening of 17 mm (p pathway for the transmission of force. This may have clinical implications for the outcome after tendon transfer. PMID:12931805

  8. Biomechanical Analysis of the Proximal Adjacent Segment after Multilevel Instrumentation of the Thoracic Spine: Do Hooks Ease the Transition?

    Science.gov (United States)

    Metzger, Melodie F; Robinson, Samuel T; Svet, Mark T; Liu, John C; Acosta, Frank L

    2016-06-01

    Study Design Biomechanical cadaveric study. Objective Clinical studies indicate that using less-rigid fixation techniques in place of the standard all-pedicle screw construct when correcting for scoliosis may reduce the incidence of proximal junctional kyphosis and improve patient outcomes. The purpose of this study is to investigate whether there is a biomechanical advantage to using supralaminar hooks in place of pedicle screws at the upper-instrumented vertebrae in a multilevel thoracic construct. Methods T7-T12 spines were biomechanically tested: (1) intact; (2) following a two-level pedicles screw fusion from T9 to T11; and after proximal extension of the fusion to T8-T9 with (3) bilateral supra-laminar hooks, (4) a unilateral hook + unilateral screw hybrid, or (5) bilateral pedicle screws. Specimens were nondestructively loaded while three-dimensional kinematics and intradiscal pressure at the supra-adjacent level were recorded. Results Supra-adjacent hypermobility was reduced when bilateral hooks were used in place of pedicle screws at the upper-instrumented level, with statistically significant differences in lateral bending and torsion (p < 0.05 and p < 0.001, respectively). Disk pressures in the supra-adjacent segment were not statistically different among top-off techniques. Conclusions The use of supralaminar hooks at the top of a multilevel posterior fusion construct reduces the stress at the proximal uninstrumented motion segment. Although further data is needed to provide a definitive link to the clinical occurrence of PJK, this in vitro study demonstrates the potential benefit of "easing" the transition between the stiff instrumented spine and the flexible native spine and is the first to demonstrate these results with laminar hooks. PMID:27190735

  9. Is proton beam therapy the future of radiotherapy? Part I: Clinical aspects; La protontherapie: avenir de la radiotherapie? Premiere partie: aspects cliniques

    Energy Technology Data Exchange (ETDEWEB)

    Bouyon-Monteau, A.; Habrand, J.L.; Datchary, J.; Alapetite, C.; Bolle, S.; Dendale, R.; Feuvret, L.; Helfre, S.; Calugaru, V. [Centre de protontherapie d' Orsay, institut Curie, campus universitaire, 91 - Orsay (France); Bouyon-Monteau, A.; Alapetite, C.; Bolle, S.; Dendale, R.; Helfre, S.; Calugaru, V.; Cosset, J.M.; Bey, P. [Departement d' oncologie-radiotherapie, institut Curie, 75 - Paris (France); Habrand, J.L.; Datchary, J. [Departement d' oncologie-radiotherapie, institut de cancerologie Gustave-Roussy, 94 - Villejuif (France); Feuvret, L. [Departement d' oncologie-radiotherapie, hopital Pitie-Salpetriere, 75 - Paris (France)

    2010-12-15

    Proton beam therapy uses positively charged particles, protons, whose physical properties improve dose-distribution (Bragg peak characterized by a sharp distal and lateral penumbra) compared with conventional photon-based radiation therapy (X-ray). These ballistic advantages apply to the treatment of deep-sited tumours located close to critical structures and requiring high-dose levels. [60-250 MeV] proton-beam therapy is now widely accepted as the 'gold standard' in specific indications in adults - ocular melanoma, chordoma and chondrosarcoma of the base of skull - and is regarded as a highly promising treatment modality in the treatment of paediatric malignancies (brain tumours, sarcomas..). This includes the relative sparing of surrounding normal organs from low and mid-doses that can cause deleterious side-effects such as radiation-induced secondary malignancies. Other clinical studies are currently testing proton beam in dose-escalation evaluations, in prostate, lung, hepatocellular cancers, etc. Clinical validation of these new indications appears necessary. To date, over 60, 000 patients worldwide have received part or all of their radiation therapy program by proton beams, in approximately 30 treatment facilities. (authors)

  10. Suggested guidelines for using systemic antimicrobials in bacterial skin infections: part 1—diagnosis based on clinical presentation, cytology and culture

    Science.gov (United States)

    Beco, L.; Guaguère, E.; Méndez, C. Lorente; Noli, C.; Nuttall, T.; Vroom, M.

    2013-01-01

    Systemic antimicrobials are critically important in veterinary healthcare, and resistance is a major concern. Antimicrobial stewardship will be important in maintaining clinical efficacy by reducing the development and spread of antimicrobial resistance. Bacterial skin infections are one of the most common reasons for using systemic antimicrobials in dogs and cats. Appropriate management of these infections is, therefore, crucial in any policy for responsible antimicrobial use. The goals of therapy are to confirm that an infection is present, identify the causative bacteria, select the most appropriate antimicrobial, ensure that the infection is treated correctly, and to identify and manage any underlying conditions. This is the first of two articles that will provide evidence-led guidelines to help practitioners address these issues. This article covers diagnosis, including descriptions of the different clinical presentations of surface, superficial and deep bacterial skin infections, how to perform and interpret cytology, and how to best use bacterial culture and sensitivity testing. Part 2 will discuss therapy, including choice of drug and treatment regimens. PMID:23292951

  11. Athletic groin pain: a biomechanical diagnosis

    OpenAIRE

    Marshall, Brendan; Moran, Kieran; Richter, Chris; Gore, Shane; King, Enda; Franklyn-Miller, Andy; Strike, Siobhan; Falvey, Eanna

    2015-01-01

    Introduction: Chronic athletic groin pain is commonly experienced in a range of football codes including soccer (Holmich et al. 2014) and gaelic football (Murphy et al. 2012). Much debate surrounds the specific aetiology of AGP but several authors have implicated, at least in part, abnormal movement control and loading in and around the hip and pelvis during play (Rabe et al. 2010, Pizarri et al. 2008). Movement control during change of direction cutting is of particular interest as it is thi...

  12. Biomechanics of the unique pterosaur pteroid

    OpenAIRE

    Palmer, Colin; Dyke, Gareth J.

    2009-01-01

    Pterosaurs, flying reptiles from the Mesozoic, had wing membranes that were supported by their arm bones and a super-elongate fourth finger. Associated with the wing, pterosaurs also possessed a unique wrist bone—the pteroid—that functioned to support the forward part of the membrane in front of the leading edge, the propatagium. Pteroid shape varies across pterosaurs and reconstructions of its orientation vary (projecting anteriorly to the wing leading edge or medially, lying alongside it) a...

  13. 尺桡骨中段双骨折四种内固定方法的临床比较研究%Clinical comparison and research of four methods of treatment to middle-part radius and ulna fracture

    Institute of Scientific and Technical Information of China (English)

    张晓峰; 李晓林; 沈国平; 罗轶

    2011-01-01

    目的 通过前瞻性研究,比较尺桡骨中段双骨折四种不同内固定治疗方法的特点和临床疗效,筛选最佳方法.方法 2004 年9 月至2008 年3 月采用尺桡骨髓内钉及加压钢板四种不同组合治疗尺桡骨中段双骨折87 例,所有病例分四组:尺桡骨双钢板(A 组),尺桡骨双髓内钉(B 组),尺骨钢板加桡骨髓内钉(C 组)和尺骨髓内钉加桡骨钢板(D 组).其中A 组21 例,B 组22 例,C 组21例,D 组23 例.分析比较手术时间、伤口大小、骨膜剥离程度、术后并发症情况,术后每月摄X 线片观察骨折愈合情况并根据Anderson 评分标准评估功能恢复情况.结果 87 例患者全部获得了随访.随访时间为12 ~26 个月,平均23.4 个月.在手术创伤评定中,B 组、C 组、D 组较A 组创伤小.并发症发生率D 组小于其他三组.87 例中84 例均获得骨折愈合,3 例骨不连.Anderson 功能评分:A 组:优11 例,良3 例,可5 例,失败2 例.B 组:优11 例,良5 例,可5 例,失败1 例.C 组:优14 例,良3例,可4 例.D 组:优20 例,良2 例,可1 例.D 组骨折愈合率及功能评分明显高于A 组、B 组、C 组(P <0.05).结论 尺桡骨中段双骨折4 种内固定方法治疗都能获得较高的骨折愈合率和功能评分,但尺骨髓内钉加桡骨钢板组手术操作简便,创伤小,骨折愈合率高,并发症少,功能恢复好,在生物力学和生物学固定上达到了良好的组合,是一种比较适合的治疗方法.%Objective A prospective study to compare the effect of using four methods of treatment to middle-part radius and ulna fracture , in order to select the best clinical pathway . Methods We have treated 87 cases of mid-radius and ulna fracture cases from September 2004 to March 2008. These patients were divided into four groups : Double-plate fixation group ( A group ) , Double-intramedullary nail fixation group ( B group) , ulnar plate and radial intramedullary nail group ( C group ) , ulnar

  14. Biomechanical analysis of skilled female gymnasts' motor actions in vaulting «rondat fllick» with the new table

    OpenAIRE

    Хмельницкая, Ирина Валерьевна; Крупеня, Светлана Васильевна

    2011-01-01

    Biomechanics descriptions of technique of motive actions of gymnasts are presented. 20 gymnasts took part in an experiment. The analysis of 72 appearances of gymnasts and 144 supporting jumps is conducted. Errors are considered in the technique of motive actions of gymnasts at implementation of supporting jumps. It is marked that frequency of the use of supporting jump «Rondat Fllick» among all of supporting jumps is 40 %. It is set that the leading elements of motive structure of technique a...

  15. Sino-European Transcontinental Basic and Clinical High-Tech Acupuncture Studies—Part 2: Acute Stimulation Effects on Heart Rate and Its Variability in Patients with Insomnia

    Directory of Open Access Journals (Sweden)

    Gerhard Litscher

    2012-01-01

    Full Text Available This second part of a series of Sino-European high-tech acupuncture studies describes the first clinical transcontinental teleacupuncture measurements in patients with insomnia. Heart rate (HR and heart rate variability (HRV measurements in 28 patients (mean age ± SD: 41.9 ± 14.6 years were performed under standardized conditions in Harbin, China, and the data analysis was performed in Graz, Austria. Similar to the first part of the series, the electrocardiograms (ECGs were recorded by an HRV Medilog AR12 system during acupuncture of the Shenmen point (HT7 on the left hand. HR decreased significantly (P<0.001 during and after acupuncture stimulation of the HT7 acupuncture point. Total HRV increased significantly (P<0.05 immediately after acupuncture stimulation, but there was no long-lasting effect. The values of the low-frequency (LF and high-frequency (HF band increased significantly after the stimulation compared to baseline values; however, the LF/HF ratio showed no significant changes. Together with the results of previous studies, the present results can serve as a solid basis for further development of acupressure or acupuncture stimulation equipment for complementary use in treating insomnia.

  16. Corneal biomechanical changes and intraocular pressure in patients with thyroid orbitopathy

    Science.gov (United States)

    Pniakowska, Zofia; Klysik, Anna; Gos, Roman; Jurowski, Piotr

    2016-01-01

    AIM To determine the relevance of the objective parameters addressing the altered biomechanical properties of cornea for glaucoma monitoring in patients with mild or moderate thyroid associated orbitopathy (TAO), and in healthy individuals. METHODS Twenty-five patients with TAO (group 1) and 25 healthy adults (group 2) were included to the study. Both groups were of a similar age and the ratio women:man. For each patient, the following parameters of both eyes were measured with ocular response analyzer (ORA): corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann correlated intraocular pressure (IOPg) and corneal compensated intraocular pressure (IOPcc). In both groups participating in our study, all measurements were performed within minutes to reduce the diurnal effects. RESULTS The mean age in group 1 was 56±11y and 76% were women, 24% were men. The mean age in group 2 was 64±11y and 68% were women, 32% were men. CH correlated negatively with IOPg in group 1 (r2=0.10, P0.05) and also no significant correlation in group 2 (r2=0.04, P>0.05). CRF mean value in group 2 (11.51±1.72 mm Hg) was higher than in group 1 (10.85±1.45 mm Hg) (P<0.05). IOPg strongly correlated with IOPcc in both groups (group 1: r2=0.79, P<0.0001; group 2: r2=0.85, P<0.0001). There was also strong correlation between CRF and CH in both populations: group 1: (r2=0.58, P<0.0001), group 2: (r2=0.41, P<0.0001). CONCLUSION Biomechanical parameters of cornea, as quantified by CH and CRF, and measured together with IOPcc, precisely reveal glaucoma staging in TAO and thus are reliable for diagnosing and follow-up in clinical practice.

  17. Primary fixation of mini slings: a comparative biomechanical study in vivo

    Directory of Open Access Journals (Sweden)

    Paulo Palma

    2012-04-01

    Full Text Available INTRODUCTION AND OBJECTIVES: The mini sling concept for stress urinary incontinence is an anatomical approach that involves placing a midurethral low-tension tape anchored to the obturator internus muscles bilaterally. They overcome the blind passage of long needles and all the related complications. There are many different devices available and because these are outpatient procedures, primary fixation plays an important role in the outcome. The objective is to evaluate the primary fixation of the various devices of attachment of the commercially available mini-slings through biomechanical tests. MATERIALS AND METHODS: A total of 45 Wistar rats were divided in 3 groups of 15 rats each. They underwent 5 subcutaneous implantation of different mini slings and one polipropilene mesh (control, as follows: TVT-Secur® (Gynecare, USA, Type 1 polypropylene mesh (control; Ophira Mini Sling System® (Promedon, Argentina, Tissue Fixation System® (TFS PTY, Australia, Zipper Sling® and "T device" (Prosurg, USA. The abdominal wall was removed on bloc at different times after implant for biomechanical evaluation, which consisted in application of unidirectional force to the extremity of the fixation system or mesh, until it was completely removed from the tissue using a tension meter (Nexygen 3.0 Universal Testing Machine - LLOYD Instruments. The force was measured in Newtons (N. RESULTS: There was significant difference in the resistance to extraction among the different fixation systems. At 7 days the Ophira Mini Sling System® presented the best fixation and "T dispositive" the worst. CONCLUSION: Ophira mini sling System® presented the best primary fixation at 7º, 14º and 30º days. The impact of this feature in the clinical setting needs to be verified.

  18. Biomechanical abnormalities and ulcers of the great toe in patients with diabetes.

    Science.gov (United States)

    Boffeli, Troy J; Bean, Jeffrey K; Natwick, James R

    2002-01-01

    A prospective analysis was conducted to identify structural and biomechanical first ray abnormalities in consecutive diabetic patients presenting with their first great toe ulcer. Twenty-six patients (33 feet) met the inclusion criteria, with seven patients having bilateral hallux ulcers. There was no other history of ulcer, trauma, or surgery on the respective limb. Data were obtained during the patients' initial presentation with a great toe ulcer and included verbal history, standardized weight bearing radiographs, and standardized objective clinical measurements. Four patients (four feet) with subungual ulcers were included because of mechanical etiology. Twenty-four of the remaining 29 involved limbs exhibited gastrocnemius/soleus equinus and two other limbs had gastrocnemius equinus. Twenty-eight of 29 had structural hallux limitus. Twenty-four had hallux interphalangeal abductus. Twenty of the 33 ulcers were located plantar-medially at the interphalangeal joint area. Other frequent findings were first ray elevatus or dorsiflexion deformity (18 of 29), functional hallux limitus (14 of 29), interphalangeal joint sesamoid bone (13 of 29), hyperextended interphalangeal joint (13 of 29), and a prominent plantar-medial condyle of the proximalaspect of the distalphalanx (7 of 29). Halluxmalleus was less common (4 of 29), but consistently associated with plantar-distal tip ulceration. Metatarsus primus adductus was also infrequent (6 of 29). This study identifies and illustrates the importance of several biomechanical and structural factors present on initial presentation of great toe ulcers. Addressing these factors may improve the success of treatment and lessen the occurrence of this common and complex problem. PMID:12500786

  19. Detection of the early keratoconus based on corneal biomechanical properties in the refractive surgery candidates

    Directory of Open Access Journals (Sweden)

    Zofia Pniakowska

    2016-01-01

    Full Text Available Context: Subclinical keratoconus is contraindication to refractive surgery. The currently used methods of preoperative screening do not always allow differentiating between healthy eyes and those with subclinical keratoconus. Aim: To evaluate biomechanical parameters of the cornea, waveform score (WS, and intraocular pressure (IOP as potentially useful adjuncts to the diagnostic algorithm for precise detection of the early keratoconus stages and selection of refractive surgery candidates. Settings and Design: Department of Ophthalmology and prospective cross-sectional study. Patients and Methods: Patients enrolled in the study were diagnosed with refractive disorders. We assessed parameters of corneal biomechanics such as corneal hysteresis (CH, corneal resistance factor (CRF, Goldman-correlated IOP (IOPg, corneal compensated IOP, WS, and keratoconus match index (KMI. They were classified into one of three groups based on the predefined KMI range: Group 1 (from 0.352 to 0.757 – 45 eyes, Group 2 (from −0.08 to 0.313 – 52 eyes, and Group 0 - control group (from 0.761 to 1.642 – 80 eyes. Results: In both study groups, IOPg, CRF, and CH were decreased when compared to control (P < 0.0001. In control group, there was positive correlation between CH and KMI (P < 0.05, with no correlations in any of the two study groups. CRF correlated positively with KMI in control (P < 0.0001 and in Group 2 (P < 0.05. Conclusions: CH and CRF, together with WS and IOPg, consist a clinically useful adjunct to detect subclinical keratoconus in patients referred for refractive surgery when based on KMI staging.

  20. L4、5侧路单枚cage椎间融合术式的生物力学及临床研究%Biomechanical and Clinical Study of L4.5 Lateral Lumbar Interbody Fusion Using Single Anatomical Threaded Cage

    Institute of Scientific and Technical Information of China (English)

    郑忠; 翁绳健; 吴立忠; 李炜明; 陈国龄

    2011-01-01

    Objective To evaluate the relative stability of L4.5 lateral lumbar interbodyfusion using single anatomical threaded cage.Methods Twelve calf spine models and dimensional element models of lateral and posterior approach were established.Pure moment and forces were applied to the top of spinal eolumn. The motion range of all the specimens was measured during the experiment. The improvement rate of lumbar pain in 33 patients who took operation from Dec. 2003 to Dec. 2006 was evaluated. Results The stability in lateral group was superior to posterior group. The effective rate of operation was 100%. The improvement rate of lumbar pain was 93.94%.The patients's satisfactory rate was 100%.Conclusion Interbody fusion of L4.5 through lateral approach using single anatomical threaded cage without internal fixation is a mini-invasive operation process. It can provide instant posterior biomechanical stiffness. It is an effective operation process of interbody fusion in lumbar.%目的 评价L4、5侧路单枚椎间融合器融合术式的稳定性及力学合理性.方法 建立L4、5侧路与后路单枚椎间融合器融合术式的三维有限元模型及小牛脊柱模型,测定二者的位移变化.临床随访2003年12月~2006年12月行侧路单枚椎间融合器融合术式33例,评价腰痛改善率.结果 实验显示侧路模型的稳定性优于后路模型.临床研究显示手术有效率100%,腰痛改善率93.94%,患者满意率100%.结论 侧路植入单枚椎间融合器融合术式是一种微创的术式,不使用椎弓根固定系统而又能够提供足够的术后即刻生物力学刚度,是一种合理有效的腰椎椎间融合术式.

  1. A prática clínica baseada em evidências: parte II - buscando as Evidências em Fontes de Informação Evidence based clinical practice: part II - searching evidence databases

    Directory of Open Access Journals (Sweden)

    Wanderley Marques Bernardo

    2004-12-01

    Full Text Available A busca da resposta a uma questão clínica bem construída pode ser realizada em inúmeras fontes de informação científica. Na dependência de onde obtemos a informação, a decisão clínica não será sustentada pelas melhores evidências disponíveis na atualidade, expondo o paciente a um risco desnecessário. A busca pode ser realizada em bases primárias, que disponibilizam os trabalhos originais, cabendo ao leitor o ônus de selecionar e analisar criticamente a validade de seus resultados. A busca pode também ser realizada em bases secundárias, que economizam o tempo do leitor na seleção metodológica e avaliação crítica. Entre as bases primárias, recomendamos o Medline e o SciELO, onde a busca pode ter início com a utilização das palavras-chaves, obtidas na construção da pergunta estruturada segundo o acrônimo P.I.C.O., em seguida, organizadas com a adição dos booleanos AND, OR ou NOT. Entre as bases secundárias que acrescem qualidade científica na seleção das evidências apresentadas, algumas fornecem respostas fundamentadas em trabalhos inviduais, como o ACPJournal Club, o Evidence Based Medicine e o InfoPoems, outras abordam questões clínicas organizadas em forma de livro, como o Clinical Evidence e o UpToDate. A Cochrane Review apresenta evidências de boa qualidade a partir de revisões sistemáticas de ensaios clínicos preferencialmente aleatorizados. A obtenção de estudos que respondem a uma questão clínica faz parte do atendimento que procura integrar a melhor evidência científica às necessidades de atendimento do paciente. Para tanto, conta com recursos tecnológicos, como os PDAs, Palmtops e Notebooks, cada vez mais adaptados para trazer a última informação divulgada pela Internet que auxilia na tomada de decisão clínica à beira do leito.The inadequacy of most of traditional sources for medical information, like textbook and review article, do not sustained the clinical decision based on

  2. A prática clínica baseada em evidências: parte II - buscando as evidências em fontes de informação Evidence based clinical practice: part II - searching evidence databases

    Directory of Open Access Journals (Sweden)

    Wanderley Marques Bernardo

    2004-01-01

    Full Text Available A busca da resposta a uma questão clínica bem construída pode ser realizada em inúmeras fontes de informação científica. Na dependência de onde obtemos a informação, a decisão clínica não será sustentada pelas melhores evidências disponíveis na atualidade, expondo o paciente a um risco desnecessário. A busca pode ser realizada em bases primárias, que disponibilizam os trabalhos originais, cabendo ao leitor o ônus de selecionar e analisar criticamente a validade de seus resultados. A busca pode também ser realizada em bases secundárias, que economizam o tempo do leitor na seleção metodológica e avaliação crítica. Entre as bases primárias, recomendamos o Medline e o SciELO, onde a busca pode ter início com a utilização das palavras-chaves, obtidas na construção da pergunta estruturada segundo o acrônimo P.I.C.O., em seguida, organizadas com a adição dos booleanos AND, OR ou NOT. Entre as bases secundárias que acrescem qualidade científica na seleção das evidências apresentadas, algumas fornecem respostas fundamentadas em trabalhos inviduais, como o ACP Journal Club, o Evidence Based Medicine e o InfoPoems, outras abordam questões clínicas organizadas em forma de livro, como o Clinical Evidence e o UpToDate. A Cochrane Review apresenta evidências de boa qualidade a partir de revisões sistemáticas de ensaios clínicos preferencialmente aleatorizados. A obtenção de estudos que respondem a uma questão clínica faz parte do atendimento que procura integrar a melhor evidência científica às necessidades de atendimento do paciente. Para tanto, conta com recursos tecnológicos, como os PDAs, Palmtops e Notebooks, cada vez mais adaptados para trazer a última informação divulgada pela Internet que auxilia na tomada de decisão clínica à beira do leito.The inadequacy of most of traditional sources for medical information, like textbook and review article, do not sustained the clinical decision based on

  3. [Biomechanics of combined Kirschner wire osteosynthesis in the human model of unstable dorsal, distal radius fractures (Colles type)].

    Science.gov (United States)

    Fritz, T; Heyer, T; Krieglstein, C; Mattern, R; Kallieris, D; Friedl, W

    1997-05-01

    In an experimental study, the biomechanical qualities of the combined Kirschner wire osteosynthesis (KWO) in the unstable Colles' fracture were analyzed. This type of pin fixation is our preferred osteosynthesis in the treatment of unstable Colles' fracture because it allows immediate functional therapy. It represents a modification of Kapandji's dynamic KWO, compensating for the insufficient volar stability by means of the conventional static KWO. Clinical experience according to the anatomical and functional results, was very encouraging suggesting that a clinical concept based on the biomechanical principles of combined KWO and its single components should be constituted. Simulation of the unstable Colles' fracture was realized by dorsal wedge osteotomy of the distal end of the radius using cadaveric material. This fracture model was subsequently pinned using the different KWO types and tested by a standardized vector energy testing device regarding its stability in the four main loading directions. The combined KWO unifies the advantage of volar stability of the conventional KWO with the high dorsal stability of dynamic KWO. The main functional principle of dynamic KWO with regard to its axial stability consists in the repositioning of the dorsal bone fragmentation zone and hence the reconstitution of cortical load transmission. Besides its good stabilization, dynamic KWO also leads to optimal alignment of the distal metaphyseal fragment. Furthermore, the experiments yielded important information about technical aspects of the surgical procedure, which helps us to avoid anatomical and functional deficiencies. Based on these experimental findings, the surgical technique of combined KWO was standardized. PMID:9303839

  4. Research Progress on Biomechanics of Vibration Therapy%振法的生物力学研究进展

    Institute of Scientific and Technical Information of China (English)

    张仲博; 房敏; 蒋诗超; 张昊; 周强

    2012-01-01

    Vibration therapy is one of the common massage techniques,which has the broad application in clinic. But,for vibration therapy operation of the norms movement,the operating frequency,the operation dynamics,operation time,many textbooks failed to give clear specification and description. At the same time,there are no detailed records for the vibration therapy kinematics and dynamics, biomechanics effect. Therefore, either the scientific research or clinical therapy should strengthen the research of the vibration therapy standardization. The paper will be related with the combination of literature and materials for vibration biomechanics research method.%振法是推拿常见治疗手法之一,在临床上有这广泛的运用.但是,对于振法操作的动作规范,操作频率,操作力度,操作时间,诸多教材描述比较模糊,未能给予清晰的规范和描述.同时,振法运动学,动力学,生物力学效应,未有详细的记录.因此,无论科研还是临床都亟需加强振法规范化的研究,文章将结合相关的教材与文献对振法的生物力学研究进行相关的梳理和综述.

  5. Sequential compression biomechanical device versus primary amputation in patients with critical limb ischemia.

    LENUS (Irish Health Repository)

    Tawfick, Wael A

    2013-10-01

    Introduction: Patients with critical limb ischemia (CLI), who are unsuitable for intervention, face the consequence of primary amputation. Sequential compression biomechanical device (SCBD) therapy provides a limb salvage option for these patients. Objectives: To assess the outcome of SCBD in patients with severe CLI who are unsuitable for revascularization. Primary end points were limb salvage and 30-day mortality. Methods: From 2005 to 2012, 189 patients with severe CLI were not suitable for revascularization. In all, 171 joined the SCBD program. We match controlled 75 primary amputations. Results: All patients were Rutherford category 4 or higher. Sustained clinical improvement was 68% at 1 year. Mean toe pressure increased from 19.9 to 35.42 mm Hg, P < .0001. Mean popliteal flow increased from 35.44 to 55.91 cm\\/sec, P < .0001. The 30-day mortality was 0.6%. Limb salvage was 94% at 5 years. Freedom from major adverse clinical events was 62.5%. All-cause survival was 69%. Median cost of managing a primary amputation patient is €29 815 compared to €3985 for SCBD. We treated 171 patients with artassist at a cost of €681 965. However, primary amputation for 75 patients cost €2 236 125. Conclusion: The SCBD therapy is a cost-effective and clinically effective solution in patients with CLI having no option of revascularization. It provides adequate limb salvage while providing relief of rest pain without any intervention.

  6. L4 fractures, biomechanics of cure foretold

    Directory of Open Access Journals (Sweden)

    Daniel Alberto Ramírez Islas

    2014-12-01

    Full Text Available Objectives: To analyze the clinical and radiographic outcomes in fracture of the fourth lumbar vertebra, under conservative or surgical treatment. Methods: Patients diagnosed with L4 fracture with or without neurological injury were studied and to whom conservative or surgical treatment was provided. Radiographic measurements were performed taking into account the kyphosis angle, the sagittal index, loss of vertebral body height, percentage of canal occlusion and height compression percentage. Results: Twenty-five patients were treated, five conservatively and 20 surgically. The vertebral kyphosis angle in both groups was 12°, no regional kyphosis was present, the sagittal index was 11.9 (Farcy, the loss of vertebral body height was 53.17%, the percentage of canal occlusion was 23% and the height compression percentage was 38.06%. The residual pain according to the visual analog scale was two in both groups. Conclusions: Patients with a fractured L4 have a satisfactory outcome with both treatments, the height of the vertebral body remains the same, the lordosis is preserved and therefore the sagittal balance, allowing recovering the mechanical functions of the spine as opposed to other segment fractures.

  7. [Biomechanics and injury prevention in road traffic].

    Science.gov (United States)

    Walz, E

    1997-05-01

    The main predicting factor for the injury severity is "speed". This fact is predominantly important with regard to the protection of pedestrians and two wheelers. Today's safety features such as new steering and breaking systems, car body construction, seat belts, head restraints and crash helmets etc. let us sometimes overlook the hazards on the road. However, further improvements can be expected from advanced restraint system combinations, reinforced frontal and lateral car structures and padding, perhaps side air bags and automatically adjusted head restraint systems. Collision reconstruction and assessment of causality are needed, e.g., in cases of soft tissue neck injuries, questionable overrunning, walking direction of impacted pedestrians, uncertain belt or helmet wearing etc. Considerable legal problems arise if the causality is judged only from clinical point of view while the important criterion of collision mechanics is not taken into account in acceptable quantitative detail. Therefore it is recommended that determining the causality of a mechanical event should be left to specially trained professionals. PMID:9244993

  8. Co-focused ultrasound and optical coherence elastography system for the study of age-related changes of biomechanical properties of crystalline lens in rabbit eyes

    Science.gov (United States)

    Wu, Chen; Han, Zhaolong; Wang, Shang; Li, Jiasong; Singh, Manmohan; Liu, Chih-hao; Aglyamov, Salavat; Emelianov, Stanislav; Manns, Fabrice; Larin, Kirill V.

    2015-03-01

    In this study, we utilize a confocal ultrasound and phase-sensitive optical coherence elastography (OCE) system to assess age-related changes in biomechanical properties of the crystalline lens in intact rabbit eyes in situ. Lowamplitude elastic deformations, induced on the surface of the lens by localized acoustic radiation force, were measured using phase-sensitive OCT. The results demonstrate that the displacements induced in young rabbit lenses are significantly larger than those in the mature lenses. Temporal analyses of the elastic waves are also demonstrated significant difference between young and old lenses, indicating that the stiffness of lens increases with the age. These results demonstrate possibility of OCE for completely noninvasive analysis and quantification of lens biomechanical properties, which could be used in many clinical and basic science applications such as surgeries and studies on lens physiology and function.

  9. Biomechanical response of two fast-growing tropical seagrass species subjected to in situ shading and sediment fertilization

    NARCIS (Netherlands)

    La Nafie, Y.A.; de los Santos, C.B.; Brun, F.G.; Mashoreng, S.; van Katwijk, M.M.; Bouma, T.J.

    2013-01-01

    Although seagrasses experience strong hydrodynamic forces, little is known about their biomechanical response in spite of the potential importance for their ecological success. We investigated how light reduction and sediment-nutrient enrichment affect biomechanical and morphological properties of t

  10. Biomechanics of front and back squat exercises

    International Nuclear Information System (INIS)

    Squat constitutes one of the most popular exercises to strengthen the muscles of the lower limbs. It is considered one of the most widely spread exercises for muscle sport training and is part of the competition movements comprised within olympic weight-lifting. In physical rehabilitation, squats are used for muscular recovery after different injuries of the lower limbs, especially the knee. In previous anterior cruciate ligament injuries, the mini-squats are generally used, in a knee flexion motion range from 0 deg. to 50 deg. because in this range the shear forces, the tibiofemoral and patellofemoral compression forces decrease related to greater flexion angles. The aim of this work is to make a comparative bidimensional study of the kinematic and dynamic variables of the excecution of the parallel squat exercise with the front and back bar. It is observed in the knee a better development of energy with the front bar, allowing a better muscular exercise with the same load. The mean power absorbed by the hip with the back bar is considerably greater, associated to the speed of the gesture

  11. Effects of conventional and slanted ventral slot procedures on the biomechanical behavior of the C5-C6 vertebral motion unit in dogs.

    Science.gov (United States)

    Yang, Haisheng; Lambrechts, Nicolaas E; Lehner, Michael; Adam, Gremah M; Packer, Rebecca A; Moore, Trevor W; Main, Russell P

    2016-08-01

    OBJECTIVE To compare the effects of conventional and slanted ventral slot procedures on the biomechanical behavior of the C5-C6 vertebral motion unit (VMU) in dogs. SAMPLE 14 vertebral columns (C4 through C7) from canine cadavers. PROCEDURES Specimens were assigned to a conventional or slanted ventral slot group (n = 7/group). For each specimen, the C5-C6 VMU was tested in ventral and dorsal bending and positive and negative axial torsion before and after surgery. Range of motion (ROM), stiffness, and energy absorption were compared between the 2 groups. RESULTS Both procedures significantly increased the ROM and stiffness and significantly decreased the energy absorption of the C5-C6 VMU in ventral and dorsal bending. Both procedures also increased the ROM in positive and negative axial torsion. In negative torsion, total stiffness and stiffness over the maximum ROM tested decreased less for the slanted slot procedure than for the conventional slot procedure. There were no significant differences between procedures for any of the other biomechanical outcomes examined. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the biomechanical response of the C5-C6 VMU to the conventional and slanted ventral slot procedures was not significantly different, especially when considering postsurgical instability induced by both procedures. This was most likely due to disruption of the nucleus pulposus and dorsal annulus fibrosus of the disk with both procedures. On the basis of these findings, neither procedure appeared biomechanically superior. Comparative clinical studies are warranted to further evaluate the 2 procedures. PMID:27463547

  12. Muscle-skeletal model of the thigh: a tool for understanding the biomechanics of gait in patients with cerebral palsy

    Science.gov (United States)

    Ravera, Emiliano Pablo; Catalfamo Formento, Paola Andrea; José Crespo, Marcos; Andrés Braidot, Ariel

    2011-12-01

    Cerebral Palsy represents the most common cause of physical disability in modern world and within the pediatrics orthopedics units. The gait analysis provides great contributions to the understanding of gait disorders in CP. Giving a more comprehensive treatment plan, including or excluding surgical procedures that can potentially decrease the number of surgical interventions in the life of these patients. Recommendations for orthopedic surgery may be based on a quantitative description of how to alter the properties probably muscle force generation, and how this affects the action of the muscle to determine how these muscles, impaired by disease or surgery, contributing to the movement of the segments of the limb during crouch gait. So the causes and appropriate treatment of gait abnormalities are difficult to determine because the movements generated by the muscular forces of these patients are not clearly understood. A correct determination of the etiology of abnormal patterns of the knee is the key to select the appropriate therapy, presenting a major challenge at present since there is no theoretical basis to determine the biomechanical causes of abnormal gait of these patients. The potential and necessity of using correct biomechanical models that consistently study the abnormalities becomes clear. Reinforcing and correcting a simple gait analysis and eliminating the unknowns when selecting the appropriate treatment is crucial in clinical settings. In this paper a computer muscle-skeletal model is proposed. The model represents a person's thigh simulating the six most representative muscles and joints of the hip and knee. In this way you can have a better understanding of gait abnormalities present in these patients. So the quality of these estimates of individual muscle dynamics facilitate better understanding of the biomechanics of gait pathologies helping to reach better diagnosis prior to surgery and rehabilitation treatments.

  13. Muscle-skeletal model of the thigh: a tool for understanding the biomechanics of gait in patients with cerebral palsy

    International Nuclear Information System (INIS)

    Cerebral Palsy represents the most common cause of physical disability in modern world and within the pediatrics orthopedics units. The gait analysis provides great contributions to the understanding of gait disorders in CP. Giving a more comprehensive treatment plan, including or excluding surgical procedures that can potentially decrease the number of surgical interventions in the life of these patients. Recommendations for orthopedic surgery may be based on a quantitative description of how to alter the properties probably muscle force generation, and how this affects the action of the muscle to determine how these muscles, impaired by disease or surgery, contributing to the movement of the segments of the limb during crouch gait. So the causes and appropriate treatment of gait abnormalities are difficult to determine because the movements generated by the muscular forces of these patients are not clearly understood. A correct determination of the etiology of abnormal patterns of the knee is the key to select the appropriate therapy, presenting a major challenge at present since there is no theoretical basis to determine the biomechanical causes of abnormal gait of these patients. The potential and necessity of using correct biomechanical models that consistently study the abnormalities becomes clear. Reinforcing and correcting a simple gait analysis and eliminating the unknowns when selecting the appropriate treatment is crucial in clinical settings. In this paper a computer muscle-skeletal model is proposed. The model represents a person's thigh simulating the six most representative muscles and joints of the hip and knee. In this way you can have a better understanding of gait abnormalities present in these patients. So the quality of these estimates of individual muscle dynamics facilitate better understanding of the biomechanics of gait pathologies helping to reach better diagnosis prior to surgery and rehabilitation treatments.

  14. Dietary water affects human skin hydration and biomechanics

    Directory of Open Access Journals (Sweden)

    Palma L

    2015-08-01

    Full Text Available Lídia Palma,1 Liliana Tavares Marques,1 Julia Bujan,2,3 Luís Monteiro Rodrigues1,4 1CBIOS – Research Center for Health Science and Technologies, Universidade Lusófona, Campo Grande, Lisboa, Portugal; 2Department of Medicine and Medical Specialities, Universidad de Alcalá de Henares, Madrid, Spain; 3CIBER-BBN, Madrid, España, Spain; 4Department of Pharmacological Sciences, School of Pharmacy, Universidade de Lisboa, Lisboa, Portugal Abstract: It is generally assumed that dietary water might be beneficial for the health, especially in dermatological (age preventing terms. The present study was designed to quantify the impact of dietary water on major indicators of skin physiology. A total of 49 healthy females (mean 24.5±4.3 years were selected and characterized in terms of their dietary daily habits, especially focused in water consumption, by a Food Frequency Questionnaire. This allowed two groups to be set – Group 1 consuming less than 3,200 mL/day (n=38, and Group 2 consuming more than 3,200 mL/day (n=11. Approximately 2 L of water were added to the daily diet of Group 2 individuals for 1 month to quantify the impact of this surplus in their skin physiology. Measurements involving epidermal superficial and deep hydration, transepidermal water loss, and several biomechanical descriptors were taken at day 0 (T0, 15 (T1, and 30 (T2 in several anatomical sites (face, upper limb, and leg. This stress test (2 L/day for 30 days significantly modified superficial and deep skin hydration, especially in Group 1. The same impact was registered with the most relevant biomechanical descriptors. Thus, in this study, it is clear that higher water inputs in regular diet might positively impact normal skin physiology, in particular in those individuals with lower daily water consumptions. Keywords: dietary water, water consume, skin hydration, TEWL, skin biomechanics

  15. Absorbable scaphoid screw development: a comparative study on biomechanics

    Science.gov (United States)

    Wang, Yi; Song, Muguo; Xu, Yongqing; He, Xiaoqing; Zhu, YueLiang

    2016-01-01

    Background The scaphoid is critical for maintaining the stability and movement of the wrist joints. This study aimed to develop a new internal fixator absorbable scaphoid screw (ASS) for fixation of the scaphoid waist after fracture and to test the biomechanical characteristics of ASS. Materials and methods An ASS was prepared using polylactic acids and designed based on scaphoid measurements and anatomic features. Twenty fractured scaphoid waist specimens were randomly divided into experimental and control groups (n=10/group). Reduction and internal fixation of the scaphoid were achieved with either Kirschner wires (K-wires) or ASS. A moving target simulator was used to test palmar flexion and dorsal extension, with the range of testing (waist movement) set from 5° of palmar flexion to 25° of dorsal extension. Flexion and extension were repeated 2,000 times for each specimen. Fracture gap displacements were measured with a computerized tomography scanning. Scaphoid tensile and bending strengths were measured by using a hydraulic pressure biomechanical system. Results Prior to biomechanical fatigue testing, fracture gap displacements were 0.16±0.02 mm and 0.22±0.02 mm in the ASS and K-wire groups, respectively. After fatigue testing, fracture gap displacements in the ASS and the K-wire groups were 0.21±0.03 mm and 1.52±0.07 mm, respectively. The tensile strengths for the ASS and K-wire groups were 0.95±0.02 MPa and 0.63±0.02 MPa, respectively. Conclusion Fixation using an ASS provided sufficient mechanical support for the scaphoid after fracture. PMID:27217756

  16. Blunt impacts to the back: Biomechanical response for model development.

    Science.gov (United States)

    Forman, Jason; Perry, Brandon; Henderson, Kyvory; Gjolaj, Joseph P; Heltzel, Sara; Lessley, David; Riley, Patrick; Salzar, Robert; Walilko, Tim

    2015-09-18

    The development of advanced injury prediction models requires biomechanical and injury tolerance information for all regions of the body. While numerous studies have investigated injury mechanics of the thorax under frontal impact, there remains a dearth of information on the injury mechanics of the torso under blunt impact to the back. A series of hub-impact tests were performed to the back surface of the mid-thorax of four mid-size male cadavers. Repeated tests were performed to characterize the biomechanical and injury response of the thorax under various impact speeds (1.5m/s, 3m/s and 5.5m/s). Deformation of the chest was recorded with a 59-gage chestband. Subject kinematics were also recorded with a high-speed optoelectronic 3D motion capture system. In the highest-severity tests, peak impact forces ranged from 6.9 to 10.5 kN. The peak change in extension angle measured between the 1st thoracic vertebra and the lumbar spine ranged from 39 to 62°. The most commonly observed injuries were strains of the costovertebral/costotransverse joint complexes, rib fractures, and strains of the interspinous and supraspinous ligaments. The majority of the rib fractures occurred in the rib neck between the costovertebral and costotransverse joints. The prevalence of rib-neck fractures suggests a novel, indirect loading mechanism resulting from bending moments generated in the rib necks caused by motion of the spine. In addition to the injury information, the biomechanical responses quantified here will facilitate the future development and validation of human body models for predicting injury risk during impact to the back. PMID:26184586

  17. Biomechanical Analysis of a Filiform Mechanosensory Hair Socket of Crickets.

    Science.gov (United States)

    Joshi, Kanishka; Mian, Ahsan; Miller, John

    2016-08-01

    Filiform mechanosensory hairs of crickets are of great interest to engineers because of the hairs' highly sensitive response to low-velocity air-currents. In this study, we analyze the biomechanical properties of filiform hairs of the cercal sensory system of a common house cricket. The cercal sensory system consists of two antennalike appendages called cerci that are situated at the rear of the cricket's abdomen. Each cercus is covered with 500-750 flow sensitive filiform mechanosensory hairs. Each hair is embedded in a complex viscoelastic socket that acts as a spring and dashpot system and guides the movement of the hair. When a hair deflects due to the drag force induced on its length by a moving air-current, the spiking activity of the neuron that innervates the hair changes and the combined spiking activity of all hairs is extracted by the cercal sensory system. Filiform hairs have been experimentally studied by researchers, though the basis for the hairs' biomechanical characteristics is not fully understood. The socket structure has not been analyzed experimentally or theoretically from a mechanical standpoint, and the characterization that exists is mathematical in nature and only provides a very rudimentary approximation of the socket's spring nature. This study aims to understand and physically characterize the socket's behavior and interaction with the filiform hair by examining hypotheses about the hair and socket biomechanics. A three-dimensional computer-aided design (CAD) model was first created using confocal microscopy images of the hair and socket structure of the cricket, and then finite-element analyses (FEAs) based on the physical conditions that the insect experiences were simulated. The results show that the socket can act like a spring; however, it has two-tier rotational spring constants during pre- and postcontacts of iris and hair bulge due to its constitutive nonstandard geometric shapes. PMID:27322099

  18. Diagnostic Assessment of Preparedness of Level One Sports Science Students for Biomechanics Modules

    Science.gov (United States)

    Dixon, Sharon J.

    2005-01-01

    The primary objective of this study was to investigate the use of a diagnostic test to assess the preparedness of level one students for a sports biomechanics module. During their first week at university, a cohort of 108 students completed a diagnostic test at the end of their first lecture in sports biomechanics, with no prior notice. Upon…

  19. How Can Sport Biomechanics Contribute to the Advance of World Record and Best Athletic Performance?

    Science.gov (United States)

    Li, Li

    2012-01-01

    Modern history has evidence that sport biomechanics provide valuable contribution in the pursuit of "faster, higher, and stronger." In this article, the contribution of sport biomechanics to the Olympic Games has been divided into three different categories: improve the physical capacity of the athletes, develop innovative techniques in a given…

  20. Mathematical simulation of the biomechanical system bone-fixator

    Science.gov (United States)

    Krasnoschekov, Viktor V.; Maslov, Leonid B.

    2001-02-01

    Problems of static and dynamic simulation of the biomechanical system consisting of the human tibia bone and external fixator apparatus as the simplest frame construction are considered. The finite element method implemented as the program code MechanicsFE3D_ESO on the basis of 20 nodal isoparametric elements is utilized. Both general stressed-deformed state of the construction under transversal loading and basic frequencies and forms of free oscillations of the system were defined by the numerical analysis. The results obtained can be used as the theoretical fundament to developing of static and vibration resonance methods for physiological state diagnostics of the regenerating osseous tissue in fracture zone.

  1. Radiological features and biomechanical patterns in Perthes disease

    International Nuclear Information System (INIS)

    This paper examines the relationship between radiologic features and biomechanical patterns in Perthes disease as shown in finite element models. A two-dimensional finite element model of a child's hip that allowed for movement at the joint line was loaded to simulate normal heel strike. The finite element method is a computer-based technique of mathematical modeling that permits calculation of the magnitude and direction of stresses, deformation, and dynamic behavior of continuous structures. In the normal hip model, maximum compressive stresses occur superolaterally and inferomedially in the femoral head, corresponding to the radiographic features of flattening and increased tear drop distance, attributable to cartilage thickening, seen in Perthes disease

  2. Interpretation Of Biomechanical Data To A Gymnastics Coach

    Science.gov (United States)

    Shierman, Gail

    1982-02-01

    Several trials of many different gymnastics skills on various pieces of apparatus were filmed and the results were studied with the coach. The time to accomplish the entire skill as well as the time for each segment of the skill was important to the coach. He was also interested in angle of release or push-off and the path of the center of gravity. Lastly, graphs of velocities and accelerations of limb segments were revealing to the coach. Biomechanical analysis has helped him see why the performances were good; he is more interested in working with the investigator in all the events in gymnastics through the medium of cinematography.

  3. Towards a Biomechanical Understanding of Tempo in the Golf Swing

    CERN Document Server

    Grober, R D; Cholewicki, Jacek; Grober, Robert D.

    2006-01-01

    It is proposed that aspects of the tempo of the golf swing can be understood in terms of a biomechanical clock. This model explains several aspects of tempo in the golf swing; including total duration of the golf swing, the ratio of backswing to downswing time, and the relative insensitivity of tempo on the length of the golf shot. We demonstrate that this clock and the resulting tempo are defined by of the rotational inertia of the body/club system and the elastic properties of the body, yielding a system which can be modeled as a simple harmonic oscillator.

  4. Absorbable scaphoid screw development: a comparative study on biomechanics

    Directory of Open Access Journals (Sweden)

    Wang Y

    2016-04-01

    Full Text Available Yi Wang, Muguo Song, Yongqing Xu, Xiaoqing He, YueLiang Zhu Department of Orthopedic Surgery, Kunming General Hospital, Chengdu Military Command, People’s Liberation Army, Kunming, Yunnan, People’s Republic of China Background: The scaphoid is critical for maintaining the stability and movement of the wrist joints. This study aimed to develop a new internal fixator absorbable scaphoid screw (ASS for fixation of the scaphoid waist after fracture and to test the biomechanical characteristics of ASS.Materials and methods: An ASS was prepared using polylactic acids and designed based on scaphoid measurements and anatomic features. Twenty fractured scaphoid waist specimens were randomly divided into experimental and control groups (n=10/group. Reduction and internal fixation of the scaphoid were achieved with either Kirschner wires (K-wires or ASS. A moving target simulator was used to test palmar flexion and dorsal extension, with the range of testing (waist movement set from 5° of palmar flexion to 25° of dorsal extension. Flexion and extension were repeated 2,000 times for each specimen. Fracture gap displacements were measured with a computerized tomography scanning. Scaphoid tensile and bending strengths were measured by using a hydraulic pressure biomechanical system.Results: Prior to biomechanical fatigue testing, fracture gap displacements were 0.16±0.02 mm and 0.22±0.02 mm in the ASS and K-wire groups, respectively. After fatigue testing, fracture gap displacements in the ASS and the K-wire groups were 0.21±0.03 mm and 1.52±0.07 mm, respectively. The tensile strengths for the ASS and K-wire groups were 0.95±0.02 MPa and 0.63±0.02 MPa, respectively.Conclusion: Fixation using an ASS provided sufficient mechanical support for the scaphoid after fracture. Keywords: absorbable scaphoid screw, biomechanics, internal fixator, Kirschner wires

  5. Implementation of reflex loops in a biomechanical finite element model.

    Science.gov (United States)

    Salin, Dorian; Arnoux, Pierre-Jean; Kayvantash, Kambiz; Behr, Michel

    2016-11-01

    In the field of biomechanics, the offer of models which are more and more realistic requires to integrate a physiological response, in particular, the controlled muscle bracing and the reflexes. The following work aims to suggest a unique methodology which couples together a sensory and motor loop with a finite element model. Our method is applied to the study of the oscillation of the elbow in the case of a biceps brachial stretch reflex. The results obtained are promising in the purpose of the development of reactive human body models. PMID:27108871

  6. Biomechanical Analysis of Treadmill Locomotion on the International Space Station

    Science.gov (United States)

    De Witt, J. K.; Fincke, R. S.; Guilliams, M. E.; Ploutz-Snyder, L. L.

    2011-01-01

    Treadmill locomotion exercise is an important aspect of ISS exercise countermeasures. It is widely believed that an optimized treadmill exercise protocol could offer benefits to cardiovascular and bone health. If training heart rate is high enough, treadmill exercise is expected to lead to improvements in aerobic fitness. If impact or bone loading forces are high enough, treadmill exercise may be expected to contribute to improved bone outcomes. Ground-based research suggests that joint loads increase with increased running speed. However, it is unknown if increases in locomotion speed results in similar increases in joint loads in microgravity. Although data exist regarding the biomechanics of running and walking in microgravity, a majority were collected during parabolic flight or during investigations utilizing a microgravity analog. The Second Generation Treadmill (T2) has been in use on the International Space Station (ISS) and records the ground reaction forces (GRF) produced by crewmembers during exercise. Biomechanical analyses will aid in understanding potential differences in typical gait motion and allow for modeling of the human body to determine joint and muscle forces during exercise. By understanding these mechanisms, more appropriate exercise prescriptions can be developed that address deficiencies. The objective of this evaluation is to collect biomechanical data from crewmembers during treadmill exercise prior to and during flight. The goal is to determine if locomotive biomechanics differ between normal and microgravity environments and to determine how combinations of subject load and speed influence joint loading during in-flight treadmill exercise. Further, the data will be used to characterize any differences in specific bone and muscle loading during locomotion in these two gravitational conditions. This project maps to the HRP Integrated Research Plan risks including Risk of Bone Fracture (Gap B15), Risk of Early Onset Osteoporosis Due to

  7. Biomechanical Factors and Injury Risk in High-Severity Rollovers

    OpenAIRE

    Moore, Tara L. A.; Vijayakumar, Vinod; Steffey, Duane L.; Ramachandran, Karuna; Corrigan, Catherine Ford

    2005-01-01

    The number of rolls, as well as other factors, has been associated with increased injury risk in rollovers. Data from NASS-CDS from 1995–2003 were used to evaluate the biomechanical implications of vehicle kinematics during multiple rolls and to evaluate the risk of injuries to different body regions during rollovers. The data showed that the risk of injury increased with increasing number of rolls. The rate of increase in risk varied by the region of the body affected and injury severity. Th...

  8. Biomechanical Analysis of the Swim-Start: A Review

    OpenAIRE

    Julien Vantorre, Didier Chollet, Ludovic Seifert

    2014-01-01

    This review updates the swim-start state of the art from a biomechanical standpoint. We review the contribution of the swim-start to overall swimming performance, the effects of various swim-start strategies, and skill effects across the range of swim-start strategies identified in the literature. The main objective is to determine the techniques to focus on in swimming training in the contemporary context of the sport. The phases leading to key temporal events of the swim-start, like water e...

  9. The genetic basis of inherited anomalies of the teeth. Part 1: clinical and molecular aspects of non-syndromic dental disorders.

    Science.gov (United States)

    Bailleul-Forestier, Isabelle; Molla, Muriel; Verloes, Alain; Berdal, Ariane

    2008-01-01

    The genetic control of dental development represents a complex series of events, which can very schematically be divided in two pathways: specification of type, size and position of each dental organ, and specific processes for the formation of enamel and dentin. Several genes linked with early tooth positioning and development, belong to signalling pathways and have morphogenesis regulatory functions in morphogenesis of other organs where they are associated with the signalling pathways. Their mutations often show pleïotropic effects beyond dental morphogenesis resulting in syndromic developmental disorders. Some genes affecting early tooth development (MSX1, AXIN2) are associated with tooth agenesis and systemic features (cleft palate, colorectal cancer). By contrast, genes involved in enamel (AMELX, ENAM, MMP20, and KLK4) and dentin (DSPP) structures are highly specific for tooth. Mutations in these genes have been identified as causes of amelogenesis imperfecta, dentinogenesis imperfecta, dentin dysplasias and anomalies of teeth number (hypo-, oligo and anodontia), which only partially overlap with the classical phenotypic classifications of dental disorders. This review of genetic basis of inherited anomalies describes, in this first paper, the molecular bases and clinical features of inherited non-syndromic teeth disorders. And in a second part, the review focus on genetic syndromes with dental involvement. PMID:18499550

  10. Osteoarthritis: new insights. Part 2: treatment approaches.

    Science.gov (United States)

    Felson, D T; Lawrence, R C; Hochberg, M C; McAlindon, T; Dieppe, P A; Minor, M A; Blair, S N; Berman, B M; Fries, J F; Weinberger, M; Lorig, K R; Jacobs, J J; Goldberg, V

    2000-11-01

    Osteoarthritis is the most common form of arthritis, affecting millions of people in the United States. It is a complex disease whose etiology bridges biomechanics and biochemistry. Evidence is growing for the role of systemic factors, such as genetics, diet, estrogen use, and bone density, and local biomechanical factors, such as muscle weakness, obesity, and joint laxity. These risk factors are particularly important in the weight-bearing joints, and modifying them may help prevent osteoarthritis-related pain and disability. Major advances in management to reduce pain and disability are yielding a panoply of available treatments ranging from nutriceuticals to chondrocyte transplantation, new oral anti-inflammatory medications, and health education. This article is part 2 of a two-part summary of a National Institutes of Health conference that brought together experts in osteoarthritis from diverse backgrounds and provided a multidisciplinary and comprehensive summary of recent advances in the prevention of osteoarthritis onset, progression, and disability. Part 2 focuses on treatment approaches; evidence for the efficacy of commonly used oral therapies is reviewed and information on alternative therapies, including nutriceuticals and acupuncture, is presented. Biomechanical interventions, such as exercise and bracing, and behavioral interventions directed toward enhancing self-management are reviewed. Current surgical approaches are described and probable future biotechnology-oriented approaches to treatment are suggested. PMID:11074906

  11. Incidence of Hyperpronation in the ACL Injured Knee: A Clinical Perspective

    OpenAIRE

    Beckett, Mark E.; Massie, Denise L.; Bowers, K. Douglas; Stoll, David A.

    1992-01-01

    Assessing abnormal biomechanics when treating various lower extremity pathologies provides the athlete with comprehensive management and promotes injury prevention. However, there have been few previous investigations of abnormal biomechanical forces on ligamentous pathologies of the knee. During this clinical study we investigated the incidence of hyperpronation in subjects who have had an anterior cruciate ligament (ACL) injury. Fifty subjects with a past medical history of ACL rupture and ...

  12. Biomechanical analysis of kinematic structure of skilled female gymnasts' technique in «Handspring» vault with a «vaulting table»

    Directory of Open Access Journals (Sweden)

    Khmelnitska I.V.

    2012-09-01

    Full Text Available The special program of perfection of sporting technique of skilled gymnasts is presented in a supporting jump. 20 skilled gymnasts took part in a pedagogical experiment. A pedagogical experiment was conducted in the conditions of preparation to the main starts of world and Ukrainian championships during 12 months. The table of contents of the special program was made by seven complexes for 5 special physical exercises (only 35 exercises. The method of biomechanics analysis of kinematics structure of motive actions of sportswomen is offered. Attention on 7 phases of supporting jump is accented, in each of which tasks decide on achievement of optimum individual biomechanics indexes. Descriptions of such constituents of perfection of technique of sportswomen are recommended: physical preparedness, rational motive mode, maximum possible parameters of the physical loadings in employment.

  13. Biphasic modeling of brain tumor biomechanics and response to radiation treatment.

    Science.gov (United States)

    Angeli, Stelios; Stylianopoulos, Triantafyllos

    2016-06-14

    Biomechanical forces are central in tumor progression and response to treatment. This becomes more important in brain cancers where tumors are surrounded by tissues with different mechanical properties. Existing mathematical models ignore direct mechanical interactions of the tumor with the normal brain. Here, we developed a clinically relevant model, which predicts tumor growth accounting directly for mechanical interactions. A three-dimensional model of the gray and white matter and the cerebrospinal fluid was constructed from magnetic resonance images of a normal brain. Subsequently, a biphasic tissue growth theory for an initial tumor seed was employed, incorporating the effects of radiotherapy. Additionally, three different sets of brain tissue properties taken from the literature were used to investigate their effect on tumor growth. Results show the evolution of solid stress and interstitial fluid pressure within the tumor and the normal brain. Heterogeneous distribution of the solid stress exerted on the tumor resulted in a 35% spatial variation in cancer cell proliferation. Interestingly, the model predicted that distant from the tumor, normal tissues still undergo significant deformations while it was found that intratumoral fluid pressure is elevated. Our predictions relate to clinical symptoms of brain cancers and present useful tools for therapy planning. PMID:27086116

  14. Biomechanics of the press-fit phenomenon in dental implantology: an image-based finite element analysis

    Directory of Open Access Journals (Sweden)

    Frisardi Gianni

    2012-05-01

    Full Text Available Abstract Background A fundamental pre-requisite for the clinical success in dental implant surgery is the fast and stable implant osseointegration. The press-fit phenomenon occurring at implant insertion induces biomechanical effects in the bone tissues, which ensure implant primary stability. In the field of dental surgery, the understanding of the key factors governing the osseointegration process still remains of utmost importance. A thorough analysis of the biomechanics of dental implantology requires a detailed knowledge of bone mechanical properties as well as an accurate definition of the jaw bone geometry. Methods In this work, a CT image-based approach, combined with the Finite Element Method (FEM, has been used to investigate the effect of the drill size on the biomechanics of the dental implant technique. A very accurate model of the human mandible bone segment has been created by processing high resolution micro-CT image data. The press-fit phenomenon has been simulated by FE analyses for different common drill diameters (DA = 2.8 mm, DB = 3.3 mm, and DC = 3.8 mm with depth L = 12 mm. A virtual implant model has been assumed with a cylindrical geometry having height L = 11 mm and diameter D = 4 mm. Results The maximum stresses calculated for drill diameters DA, DB and DC have been 12.31 GPa, 7.74 GPa and 4.52 GPa, respectively. High strain values have been measured in the cortical area for the models of diameters DA and DB, while a uniform distribution has been observed for the model of diameter DC . The maximum logarithmic strains, calculated in nonlinear analyses, have been ϵ = 2.46, 0.51 and 0.49 for the three models, respectively. Conclusions This study introduces a very powerful, accurate and non-destructive methodology for investigating the effect of the drill size on the biomechanics of the dental implant technique. Further studies could aim at understanding how different drill

  15. Persistent Biomechanical Alterations After ACL Reconstruction Are Associated With Early Cartilage Matrix Changes Detected by Quantitative MR

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    Amano, Keiko; Pedoia, Valentina; Su, Favian; Souza, Richard B.; Li, Xiaojuan; Ma, C. Benjamin

    2016-01-01

    Background: The effectiveness of anterior cruciate ligament (ACL) reconstruction in preventing early osteoarthritis is debated. Restoring the original biomechanics may potentially prevent degeneration, but apparent pathomechanisms have yet to be described. Newer quantitative magnetic resonance (qMR) imaging techniques, specifically T1ρ and T2, offer novel, noninvasive methods of visualizing and quantifying early cartilage degeneration. Purpose: To determine the tibiofemoral biomechanical alterations before and after ACL reconstruction using magnetic resonance imaging (MRI) and to evaluate the association between biomechanics and cartilage degeneration using T1ρ and T2. Study Design: Cohort study; Level of evidence, 2. Methods: Knee MRIs of 51 individuals (mean age, 29.5 ± 8.4 years) with unilateral ACL injuries were obtained prior to surgery; 19 control subjects (mean age, 30.7 ± 5.3 years) were also scanned. Follow-up MRIs were obtained at 6 months and 1 year. Tibial position (TP), internal tibial rotation (ITR), and T1ρ and T2 were calculated using an in-house Matlab program. Student t tests, repeated measures, and regression models were used to compare differences between injured and uninjured sides, observe longitudinal changes, and evaluate correlations between TP, ITR, and T1ρ and T2. Results: TP was significantly more anterior on the injured side at all time points (P < .001). ITR was significantly increased on the injured side prior to surgery (P = .033). At 1 year, a more anterior TP was associated with elevated T1ρ (P = .002) and T2 (P = .026) in the posterolateral tibia and with decreased T2 in the central lateral femur (P = .048); ITR was associated with increased T1ρ in the posteromedial femur (P = .009). ITR at 6 months was associated with increased T1ρ at 1 year in the posteromedial tibia (P = .029). Conclusion: Persistent biomechanical alterations after ACL reconstruction are related to significant changes in cartilage T1ρ and T2 at 1 year

  16. Endothelial cells and cathepsins: Biochemical and biomechanical regulation.

    Science.gov (United States)

    Platt, Manu O; Shockey, W Andrew

    2016-03-01

    Cathepsins are mechanosensitive proteases that are regulated not only by biochemical factors, but are also responsive to biomechanical forces in the cardiovascular system that regulate their expression and activity to participate in cardiovascular tissue remodeling. Their elastinolytic and collagenolytic activity have been implicated in atherosclerosis, abdominal aortic aneurysms, and in heart valve disease, all of which are lined by endothelial cells that are the mechanosensitive monolayer of cells that sense and respond to fluid shear stress as the blood flows across the surfaces of the arteries and valve leaflets. Inflammatory cytokine signaling is integrated with biomechanical signaling pathways by the endothelial cells to transcribe, translate, and activate either the cysteine cathepsins to remodel the tissue or to express their inhibitors to maintain healthy cardiovascular tissue structure. Other cardiovascular diseases should now be included in the study of the cysteine cathepsin activation because of the additional biochemical cues they provide that merges with the already existing hemodynamics driving cardiovascular disease. Sickle cell disease causes a chronic inflammation including elevated TNFα and increased numbers of circulating monocytes that alter the biochemical stimulation while the more viscous red blood cells due to the sickling of hemoglobin alters the hemodynamics and is associated with accelerated elastin remodeling causing pediatric strokes. HIV-mediated cardiovascular disease also occurs earlier in than the broader population and the influence of HIV-proteins and antiretrovirals on endothelial cells must be considered to understand these accelerated mechanisms in order to identify new therapeutic targets for prevention. PMID:26458976

  17. Biomechanical modelling and evaluation of construction jobs for performance improvement.

    Science.gov (United States)

    Parida, Ratri; Ray, Pradip Kumar

    2012-01-01

    Occupational risk factors, such as awkward posture, repetition, lack of rest, insufficient illumination and heavy workload related to construction-related MMH activities may cause musculoskeletal disorders and poor performance of the workers, ergonomic design of construction worksystems was a critical need for improving their health and safety wherein a dynamic biomechanical models were required to be empirically developed and tested at a construction site of Tata Steel, the largest steel making company of India in private sector. In this study, a comprehensive framework is proposed for biomechanical evaluation of shovelling and grinding under diverse work environments. The benefit of such an analysis lies in its usefulness in setting guidelines for designing such jobs with minimization of risks of musculoskeletal disorders (MSDs) and enhancing correct methods of carrying out the jobs leading to reduced fatigue and physical stress. Data based on direct observations and videography were collected for the shovellers and grinders over a number of workcycles. Compressive forces and moments for a number of segments and joints are computed with respect to joint flexion and extension. The results indicate that moments and compressive forces at L5/S1 link are significant for shovellers while moments at elbow and wrist are significant for grinders. PMID:22317733

  18. Biomechanical determinants of elite rowing technique and performance.

    Science.gov (United States)

    Buckeridge, E M; Bull, A M J; McGregor, A H

    2015-04-01

    In rowing, the parameters of injury, performance, and technique are all interrelated and in dynamic equilibrium. Whilst rowing requires extreme physical strength and endurance, a high level of skill and technique is essential to enable an effective transfer of power through the rowing sequence. This study aimed to determine discrete aspects of rowing technique, which strongly influence foot force production and asymmetries at the foot-stretchers, as these are biomechanical parameters often associated with performance and injury risk. Twenty elite female rowers performed an incremental rowing test on an instrumented rowing ergometer, which measured force at the handle and foot-stretchers, while three-dimensional kinematic recordings of the ankle, knee, hip, and lumbar-pelvic joints were made. Multiple regression analyses identified hip kinematics as a key predictor of foot force output (R(2)  = 0.48), whereas knee and lumbar-pelvic kinematics were the main determinants in optimizing the horizontal foot force component (R(2)  = .41). Bilateral asymmetries of the foot-stretchers were also seen to significantly influence lumbar-pelvic kinematics (R(2)  = 0.43) and pelvic twisting (R(2)  = 0.32) during the rowing stroke. These results provide biomechanical evidence toward aspects of technique that can be modified to optimize force output and performance, which can be of direct benefit to coaches and athletes. PMID:25039605

  19. Biomechanical properties of decellularized porcine pulmonary valve conduits.

    Science.gov (United States)

    Seebacher, Gernot; Grasl, Christian; Stoiber, Martin; Rieder, Erwin; Kasimir, Marie-Theres; Dunkler, Daniela; Simon, Paul; Weigel, Günter; Schima, Heinrich

    2008-01-01

    Tissue-engineered heart valves constructed from a xenogeneic or allogeneic decellularized matrix might overcome the disadvantages of current heart valve substitutes. One major necessity besides effective decellularization is to preserve the biomechanical properties of the valve. Native and decellularized porcine pulmonary heart valve conduits (PPVCs) (with [n = 10] or without [n = 10] cryopreservation) were compared to cryopreserved human pulmonary valve conduits (n = 7). Samples of the conduit were measured for wall thickness and underwent tensile tests. Elongation measurement was performed with a video extensometer. Decellularized PPVC showed a higher failure force both in longitudinal (+73%; P < 0.01) and transverse (+66%; P < 0.001) direction compared to human homografts. Failure force of the tissue after cryopreservation was still higher in the porcine group (longitudinal: +106%, P < 0.01; transverse: +58%, P < 0.001). In comparison to human homografts, both decellularized and decellularized cryopreserved porcine conduits showed a higher extensibility in longitudinal (decellularized: +61%, P < 0.001; decellularized + cryopreserved: +51%, P < 0.01) and transverse (decellularized: +126%, P < 0.001; decellularized + cryopreserved: +118%, P < 0.001) direction. Again, cryopreservation did not influence the biomechanical properties of the decellularized porcine matrix. PMID:18181800

  20. Rotational biomechanics of the elite golf swing: benchmarks for amateurs.

    Science.gov (United States)

    Meister, David W; Ladd, Amy L; Butler, Erin E; Zhao, Betty; Rogers, Andrew P; Ray, Conrad J; Rose, Jessica

    2011-08-01

    The purpose of this study was to determine biomechanical factors that may influence golf swing power generation. Three-dimensional kinematics and kinetics were examined in 10 professional and 5 amateur male golfers. Upper-torso rotation, pelvic rotation, X-factor (relative hip-shoulder rotation), O-factor (pelvic obliquity), S-factor (shoulder obliquity), and normalized free moment were assessed in relation to clubhead speed at impact (CSI). Among professional golfers, results revealed that peak free moment per kilogram, peak X-factor, and peak S-factor were highly consistent, with coefficients of variation of 6.8%, 7.4%, and 8.4%, respectively. Downswing was initiated by reversal of pelvic rotation, followed by reversal of upper-torso rotation. Peak X-factor preceded peak free moment in all swings for all golfers, and occurred during initial downswing. Peak free moment per kilogram, X-factor at impact, peak X-factor, and peak upper-torso rotation were highly correlated to CSI (median correlation coefficients of 0.943, 0.943, 0.900, and 0.900, respectively). Benchmark curves revealed kinematic and kinetic temporal and spatial differences of amateurs compared with professional golfers. For amateurs, the number of factors that fell outside 1-2 standard deviations of professional means increased with handicap. This study identified biomechanical factors highly correlated to golf swing power generation and may provide a basis for strategic training and injury prevention. PMID:21844613