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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.

  2. Biomechanics of the thorax - research evidence and clinical expertise.

    Science.gov (United States)

    Lee, Diane Gail

    2015-07-01

    Understanding the biomechanics of the thorax is critical for understanding its role in multiple conditions since the thorax is part of many integrated systems including the musculoskeletal, respiratory, cardiac, digestive and urogynecological. The thorax is also an integrated system within itself and an element of the whole body/person. Therefore, understanding the biomechanics of the thorax is fundamental to all forms of treatment for multiple conditions. The interpretation of movement examination findings depends on one's view of optimal biomechanics and the influential factors. This article will provide a synopsis of the current state of research evidence as well as observations from clinical experience pertaining to the biomechanics of the thorax in order to help clinicians organise this knowledge and facilitate evidence-based and informed management of the, often complex, patient with or without thoracic pain and impairment. The integrated systems model (ISM) will be introduced as a way to determine when the noted biomechanical findings are relevant to a patient's clinical presentation.

  3. Contribution of biomechanics to clinical practice in orthopaedics.

    Science.gov (United States)

    Woo, Savio L-Y

    2004-01-01

    Biomechanics is a field that has a very long history. It was described in ancient Chinese and Greek literature as early as 400-500 BC. The foundation of biomechanics, however, was laid during a period between the 1500's to 1700's by renowned personalities, da Vinci, Galileo, Borelli, Hooke, Newton, and so (Fung, Y.C., Biomechanics: Mechanical Properties of Living Tissues, 2nd Ed. Springer Verlag, Chapter 1, 1993). Beginning in the 1950's, Muybridge, Steindler, Inman, Lissner, and Hirsch performed the pioneering work on musculoskeletal biomechanics and the foundation of orthopaedic biomechanics was formed. For the following two decades, the field has blossomed and significant contributions in the biomechanics of bone, articular cartilage, soft tissues, upper and lower extremities, spine and so on has been made. More sophisticated equipment, coupled with mathematical modeling and better engineering design, has enabled us to make great strides. Bioengineers, in collaboration with orthopaedic surgeons, have translated many laboratory discoveries into clinical practice, leading to improved patient treatment and outcome. In the past 30 years, my colleagues and I have focused our research on the biomechanics of musculoskeletal soft tissues, ligaments and tendons, in particular. Therefore, in this lecture, the function of knee ligaments, the associated homeostatic responses secondary to immobilization and exercise, and healing of the ligaments will be reviewed. Examples of scientific findings that help to guide the surgical management of injury to ligaments will be given. New ideas on functional tissue engineering to improve the healing of knee ligaments and tendons will be presented. We have learned that tendons and ligaments are indeed complex biological tissues. To fully understand their behavior, healing and remodelling processes, this author advocates major efforts be made to bring molecular biologists, morphologists, biochemists, bioengineers, physical therapists and

  4. Biomechanics: an integral part of sport science and sport medicine.

    Science.gov (United States)

    Elliott, B

    1999-12-01

    Biomechanics is one of the disciplines in the field of Human Movement and Exercise Science and it can be divided into three broad categories from a research perspective. Clinical biomechanics involves research in the areas of gait, neuromuscular control, tissue mechanics, and movement evaluation during rehabilitation from either injury or disease. Occupational biomechanics typically involves research in the areas of ergonomics and human growth or morphology as they influence movement. While these two categories will briefly be discussed, the primary aim of this paper is to show the role of biomechanics in sports science and sports medicine. Research in sports biomechanics may take the form of describing movement from a performance enhancement (such as matching of impulse curves in rowing) or injury reduction perspective (such as diving in swimming or the assessment of knee joint loading during downhill walking). However, the strength of sports biomechanics research is the ability to establish an understanding of causal mechanisms for selected movements (such as the role of internal rotation of the upper arm in hitting or striking, and the influence of elastic energy and muscle pre-stretch in stretch-shorten-cycle actions). The growth of modelling and computer simulation has further enhanced the potential use of sports biomechanics research (such as quantification of knee joint ligament forces from a dynamic model and optimising gymnastics performance through simulation of in-flight movements). Biomechanics research may also play an integral role in reducing the incidence and severity of sporting injuries (such as identification of the causes of back injuries in cricket, and the causes of knee joint injuries in sport). In the following discussion no attempt will be made to reference all papers published in each of these areas because of the enormity of the task. Published and current work from the biomechanics laboratory at the Department of Human Movement and

  5. 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 cli...

  6. 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…

  7. 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…

  8. Translating ocular biomechanics into clinical practice: current state and future prospects.

    Science.gov (United States)

    Girard, Michaël J A; Dupps, William J; Baskaran, Mani; Scarcelli, Giuliano; Yun, Seok H; Quigley, Harry A; Sigal, Ian A; Strouthidis, Nicholas G

    2015-01-01

    Biomechanics is the study of the relationship between forces and function in living organisms and is thought to play a critical role in a significant number of ophthalmic disorders. This is not surprising, as the eye is a pressure vessel that requires a delicate balance of forces to maintain its homeostasis. Over the past few decades, basic science research in ophthalmology mostly confirmed that ocular biomechanics could explain in part the mechanisms involved in almost all major ophthalmic disorders such as optic nerve head neuropathies, angle closure, ametropia, presbyopia, cataract, corneal pathologies, retinal detachment and macular degeneration. Translational biomechanics in ophthalmology, however, is still in its infancy. It is believed that its use could make significant advances in diagnosis and treatment. Several translational biomechanics strategies are already emerging, such as corneal stiffening for the treatment of keratoconus, and more are likely to follow. This review aims to cultivate the idea that biomechanics plays a major role in ophthalmology and that the clinical translation, lead by collaborative teams of clinicians and biomedical engineers, will benefit our patients. Specifically, recent advances and future prospects in corneal, iris, trabecular meshwork, crystalline lens, scleral and lamina cribrosa biomechanics are discussed.

  9. Biomechanical and Clinical Studies in EndoVascular Aortic Repair

    NARCIS (Netherlands)

    Nauta, FJH

    2016-01-01

    Objectives This thesis investigates biomechanical and clinical performances of endovascular repair for thoracic aortic dissection (AD) and aneurysm. Insights from both medical and bio-engineering perspectives are pursued with the aim of providing scientific data that will help guide endovascular aor

  10. 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.

  11. 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

  12. History of spine biomechanics: part I--the pre-Greco-Roman, Greco-Roman, and medieval roots of spine biomechanics.

    Science.gov (United States)

    Naderi, Sait; Andalkar, Niteen; Benzel, Edward C

    2007-02-01

    The roots of spine biomechanics reside in the Antiquity and the Medieval and Renaissance periods. A review of historical treatises reveals detailed information regarding this often historically neglected discipline. Ancient medical, philosophical, and physical documents were reviewed, as they pertained to the historical foundation of spine biomechanics. These included medical case reports and observations of nature and motion by ancient philosophers and scientists. These documents heavily influenced the portion of the scientific literature that we now regard as "spine biomechanics" up through the Renaissance. The focus of Part I of this two-part series is placed on the ancient and medieval biomechanics-related literature and on associated literature that influenced the development of the field of modern spine biomechanics.

  13. Basic kinematics and biomechanics of the patellofemoral joint part 2: the patella in total knee arthroplasty.

    Science.gov (United States)

    Schindler, Oliver S

    2012-02-01

    Patellar and femoral component in total knee arthroplasty are inextricably linked as a functional unit. The configuration of this unit has been a matter of ongoing debate, and the myriad of different patellar and femoral components currently available reflect the lack of consensus with respect to the ideal design. One of the major challenges is to overcome the biomechanical disadvantages of a small contact area through which high contact pressures are transferred, making this mechanical construct the weakest part of the prosthetic knee. Contact areas are highly dependent on the congruency of the patellofemoral joint articulation, and are significantly smaller for dome shaped patellar components compared to those of more anatomic designs. However, when exposed to 3-dimensional movements, the contact areas of the dome shaped patella are significantly greater, indicating enhanced forgiveness regarding patellar malpositioning. Although contact stresses, a function of implant design and surface conformity, can reach levels far beyond the yield strength of UHMWPE, catastrophic failure of resurfaced patellar components, commonly seen in metal backed patellae, fashionable in the 1980s, has rarely been observed since. Although plastic deformation and wear of UHMWPE continue to represent a problem, in the absence of suitable alternatives polyethylene remains the bearing surface of choice. The appreciation of the consequences of the mechanical environment on the behaviour of the patellofemoral joint is of particular importance in the endeavour to develop knee replacement systems which provide satisfactory function together with clinical long-term success.

  14. Stability of the Elbow Joint: Relevant Anatomy and Clinical Implications of In Vitro Biomechanical Studies

    NARCIS (Netherlands)

    J. de Haan (Jeroen); D. Eygendaal (Denise); N.W.L. Schep (Niels); G.J. Kleinrensink (Gert Jan); W.E. Tuinebreijer (Wim); D. den Hartog (Dennis)

    2011-01-01

    textabstractAbstract: The aim of this literature review is to describe the clinical anatomy of the elbow joint based on information from in vitro biomechanical studies. The clinical consequences of this literature review are described and recommendations are given for the treatment of elbow joint di

  15. 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.

  16. Biomechanical considerations for the restoration of endodontically treated teeth: a systematic review of the literature-Part 1. Composition and micro- and macrostructure alterations

    OpenAIRE

    Dietschi, Didier; Duc, Olivier; Krejci, Ivo; Sadan, Avishai

    2007-01-01

    The specific biomechanical alterations related to vitality loss or endodontic procedures are confusing issues for the practitioner and have been controversially approached from a clinical standpoint. The aim of part 1 of this literature review is to present an overview of the current knowledge about composition changes, structural alterations, and status following endodontic therapy and restorative procedures. The basic search process included a systematic review of the PubMed/Medline databas...

  17. Clinical and biomechanical perspectives on pressure injury prevention research: The case of prophylactic dressings.

    Science.gov (United States)

    Gefen, A; Kottner, J; Santamaria, N

    2016-10-01

    In this perspective paper, we discuss clinical and biomechanical viewpoints on pressure injury (or pressure ulcer) prevention research. We have selected to focus on the case of prophylactic dressings for pressure injury prevention, and the background of the historical context of pressure injury research, as an exemplar to illuminate some of the good and not so good in current biomechanical and clinical research in the wound prevention and care arena. Investigators who are conducting medical or clinical research in academia, in medical settings or in industry to determine the efficacy of wound prevention and care products could benefit from applying some basic principles that are detailed in this paper, and that should leverage the research outcomes, thereby contributing to setting higher standards in the field.

  18. Tracking human position and lower body parts using Kalman and particle filters constrained by human biomechanics.

    Science.gov (United States)

    Martinez del Rincon, Jesús; Makris, Dimitrios; Orrite Urunuela, Carlos; Nebel, Jean-Christophe

    2011-02-01

    In this paper, a novel framework for visual tracking of human body parts is introduced. The approach presented demonstrates the feasibility of recovering human poses with data from a single uncalibrated camera by using a limb-tracking system based on a 2-D articulated model and a double-tracking strategy. Its key contribution is that the 2-D model is only constrained by biomechanical knowledge about human bipedal motion, instead of relying on constraints that are linked to a specific activity or camera view. These characteristics make our approach suitable for real visual surveillance applications. Experiments on a set of indoor and outdoor sequences demonstrate the effectiveness of our method on tracking human lower body parts. Moreover, a detail comparison with current tracking methods is presented.

  19. Sports biomechanics in the research of the Department of Biomechanics of University School of Physical Education in Poznań. Part 1. Biomechanics of rowing: tests on rowing ergometers, reconstruction and synthesis.

    Science.gov (United States)

    Dworak, Lechosław B

    2010-01-01

    The purpose of this study is to reconstruct the early phase of scientific research conducted at the Department of Biomechanics of the University School of Physical Education in Poznan, particularly the work on biomechanics of rowing, conducted as part of the Ministerial Project PR 105, entitled "The effectiveness of training and competition as well as regeneration in sports". Three kinds of research have been described, carried out with the use of the rowing ergometers. The first was the research on neuromuscular coordination in the rowing cycle, the second was the research on kinematic and dynamic characteristics of rowing on the Universal Rowing Ergometer UEW - 1, while the last one concerned determination of maximum forces generated by functional muscle groups in two characteristic rowing positions within the closed biochain of the torso and the limbs.

  20. Biomechanical principle of arcus plantaris and its clinical application

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To analyze the principle mechanism of the arcus plantaris and its clinical application. Methods: The states of forces sustained by the arcus plantaris were analyzed and calculated according to the mechanism of the quadratic parabolic arch. Results: The aponeurosis plantaris corresponded to the pull rod of the arcus plantaris. The medial and lateral longitudinal arches formed by the pedal bones were stable with the rod, but unstable without the rod. In the latter condition, on loading, the force sustained by the parabolic arch became a force sustained by a simple beam, and the arcus plantaris tended to disappear and to be flattened.Clinically, 240 feet with talipes equinus were treated with triple arthrodesis. In 34 out of the reexamined 156 feet, the aponeurosis plantaris was cut in addition to the triple arthrodesis and was immobilized with cast for 3 months.One or two years later, their arcus plantaris disappeared,pain developed when walking, and some of them walked with the midtarsai joint against the ground. Then, the triple arthrodesis and shortening of the aponeurosis plantaris were applied on 18 cases, and osteotomy of the calcaneus and reconstruction of the aponeurosis plantaris were made on 10 cases and satisfactory effects were obtained. Conclusions: In order to achieve satisfactory therapeutic effects of the triple arthrodesis, we should reestablish the arcus plantaris and accurately treat the aponeurosis plantaris for the balance of the surrounding muscle force.

  1. Proximal humeral fractures: a biomechanical comparison of locking plate constructs in a cadaveric 3-part fracture model.

    Science.gov (United States)

    Rose, David M; Sutter, Edward G; Mears, Simon C; Gupta, Rohit R; Belkoff, Stephen M

    2010-11-01

    The purpose of our study was to biomechanically compare, under cyclic loading conditions, fracture site motion, humeral head collapse, and intra-articular hardware penetration in simulated 3-part osteoporotic proximal humeral fractures stabilized with 1 of 2 locking-plate constructs. We performed fixation on simulated 3-part proximal humeral fractures in 10 pairs of cadaveric osteoporotic humeri with a Hand Innovations S3 Proximal Humerus Plate (S3 plate) or an LCP Proximal Humerus Plate (LCP plate; 1 each for each pair). The specimens were potted, mounted on a materials testing machine, and subjected to 5000 cycles of abduction in the scapular plane, loading through the supraspinatus tendon. Interfragmentary displacement at 2 virtual points (the most medial aspect of the calcar and the most superior aspect of the osteotomy line between the greater tuberosity and humeral head) was measured using an optical tracking system. Humeral head rotation was also measured. We used a generalized linear latent and mixed model to check for an effect of cyclic loading and treatment on the parameters of interest (significance, P fracture site motion, it is unknown whether the magnitude of the motion is clinically significant.

  2. Proximal Humeral Fractures: A Biomechanical Comparison of Locking Plate Constructs in a Cadaveric 3-Part Fracture Model

    OpenAIRE

    2010-01-01

    The purpose of our study was to biomechanically compare, under cyclic loading conditions, fracture site motion, humeral head collapse, and intra-articular hardware penetration in simulated 3-part osteoporotic proximal humeral fractures stabilized with 1 of 2 locking-plate constructs. We performed fixation on simulated 3-part proximal humeral fractures in 10 pairs of cadaveric osteoporotic humeri with a Hand Innovations S3 Proximal Humerus Plate (S3 plate) or an LCP Proximal Humerus Plate (LCP...

  3. 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.

  4. Acetabular allograft reconstruction in total hip arthroplasty. Part I: Current concepts in biomechanics.

    Science.gov (United States)

    Stiehl, J B

    1991-04-01

    Allograft reconstruction has become an essential tool for restoration of acetabular bone stock lost in failed total hip arthroplasty or resected in tumor reconstruction. This first segment of a two-part review will discuss the current status of allograft applications, together with pertinent biologic and biochemical aspects. Part II will address surgical considerations and recent clinical experience.

  5. Energy storage and release of prosthetic feet. Part 1: Biomechanical analysis related to user benefits.

    Science.gov (United States)

    Postema, K; Hermens, H J; de Vries, J; Koopman, H F; Eisma, W H

    1997-04-01

    The energy storing and releasing behaviour of 2 energy storing feet (ESF) and 2 conventional prosthetic feet (CF) were compared (ESF: Otto Bock Dynamic Pro and Hanger Quantum; CF: Otto Bock Multi Axial and Otto Bock Lager). Ten trans-tibial amputees were selected. The study was designed as a double-blind, randomised trial. For gait analysis a VICON motion analysis system was used with 2 AMTI force platforms. A special measuring device was used for measuring energy storage and release of the foot during a simulated step. The impulses of the anteroposterior component of the ground force showed small, statistically non-significant differences (deceleration phase: 22.7-23.4 Ns; acceleration phase: 17.0-18.4 Ns). The power storage and release phases as well as the net results also showed small differences (maximum difference in net result is 0.03 J kg-1). It was estimated that these differences lead to a maximum saving of 3% of metabolic energy during walking. It was considered unlikely that the subjects would notice this difference. It was concluded that during walking differences in mechanical energy expenditure of this magnitude are probably not of clinical relevance. Ankle power, as an indicator for energy storage and release gave different results to the energy storage and release as measured with the special test device, especially during landing response. In the biomechanical model (based on inverse dynamics) used in the gait analysis the deformation of the material is not taken into consideration and hence this method of gait analysis is probably not suitable for calculation of shock absorption.

  6. Biomechanics of the ankle joint and clinical outcomes of total ankle replacement.

    Science.gov (United States)

    Michael, Junitha M; Golshani, Ashkahn; Gargac, Shawn; Goswami, Tarun

    2008-10-01

    Until the 1970s ankle arthrodesis was considered to be the "gold-standard" to treat arthritis. But the low fusion rate of ankle arthrodeses along with the inability to achieve normal range of motion led to the growing interest in the development of total ankle replacements. Though the short-term outcomes were good, their long-term outcomes were not as promising. To date, most models do not exactly mimic the anatomical functionality of a natural ankle joint. Therefore, research is being conducted worldwide to either enhance the existing models or develop new models while understanding the intricacies of the joint more precisely. This paper reviews the anatomical and biomechanical aspects of the ankle joint. Also, the evolution and comparison of clinical outcomes of various total ankle replacements are presented.

  7. The prevention of diabetic foot ulceration: how biomechanical research informs clinical practice

    Directory of Open Access Journals (Sweden)

    Frank E. DiLiberto

    Full Text Available ABSTRACT Background Implementation of interprofessional clinical guidelines for the prevention of neuropathic diabetic foot ulceration has demonstrated positive effects regarding ulceration and amputation rates. Current foot care recommendations are primarily based on research regarding the prevention of ulcer recurrence and focused on reducing the magnitude of plantar stress (pressure overload. Yet, foot ulceration remains to be a prevalent and debilitating consequence of Diabetes Mellitus. There is limited evidence targeting the prevention of first-time ulceration, and there is a need to consider additional factors of plantar stress to supplement current guidelines. Objectives The first purpose of this article is to discuss the biomechanical theory underpinning diabetic foot ulcerations and illustrate how plantar tissue underloading may precede overloading and breakdown. The second purpose of this commentary is to discuss how advances in biomechanical foot modeling can inform clinical practice in the prevention of first-time ulceration. Discussion Research demonstrates that progressive weight-bearing activity programs to address the frequency of plantar stress and avoid underloading do not increase ulceration risk. Multi-segment foot modeling studies indicate that dynamic foot function of the midfoot and forefoot is compromised in people with diabetes. Emerging research demonstrates that implementation of foot-specific exercises may positively influence dynamic foot function and improve plantar stress in people with diabetes. Conclusion Continued work is needed to determine how to best design and integrate activity recommendations and foot-specific exercise programs into the current interprofessional paradigm for the prevention of first-time ulceration in people with Diabetes Mellitus.

  8. FUNDAMENTALS OF BIOMECHANICS

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    Duane Knudson

    2007-09-01

    Full Text Available DESCRIPTION This book provides a broad and in-depth theoretical and practical description of the fundamental concepts in understanding biomechanics in the qualitative analysis of human movement. PURPOSE The aim is to bring together up-to-date biomechanical knowledge with expert application knowledge. Extensive referencing for students is also provided. FEATURES This textbook is divided into 12 chapters within four parts, including a lab activities section at the end. The division is as follows: Part 1 Introduction: 1.Introduction to biomechanics of human movement; 2.Fundamentals of biomechanics and qualitative analysis; Part 2 Biological/Structural Bases: 3.Anatomical description and its limitations; 4.Mechanics of the musculoskeletal system; Part 3 Mechanical Bases: 5.Linear and angular kinematics; 6.Linear kinetics; 7.Angular kinetics; 8.Fluid mechanics; Part 4 Application of Biomechanics in Qualitative Analysis :9.Applying biomechanics in physical education; 10.Applying biomechanics in coaching; 11.Applying biomechanics in strength and conditioning; 12.Applying biomechanics in sports medicine and rehabilitation. AUDIENCE This is an important reading for both student and educators in the medicine, sport and exercise-related fields. For the researcher and lecturer it would be a helpful guide to plan and prepare more detailed experimental designs or lecture and/or laboratory classes in exercise and sport biomechanics. ASSESSMENT The text provides a constructive fundamental resource for biomechanics, exercise and sport-related students, teachers and researchers as well as anyone interested in understanding motion. It is also very useful since being clearly written and presenting several ways of examples of the application of biomechanics to help teach and apply biomechanical variables and concepts, including sport-related ones

  9. Biomechanical and clinical study on screw hook fixation after direct repair of lumbar spondylolysis

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jian; LIU Fan; SHI Hong-guang; FAN Jian; ZHAO Wei-dong; WANG You-hua; CAI Yu-hui

    2006-01-01

    Objective: To evaluate the biomechanical effect and clinical results of hook screw fixation after direct repair of lumbar spondylous defects in the pars interarticularis.Methods: L2-L6 spines of 8 fresh-frozen and thawed calf cadavers were used for mechanical testing. Bilateral spondylous defects were created in the L4 vertebra. The intervertebral rotation ranges between L4 and Ls were scanned and computerized in various states of motion, such as flexion/extension, lateral bending and torsional loadings applied on the intact spine and the spondylous spine when the spondylous spine was fixed with modified Scott's fixation, hook screw fixation and Buck's fixation sequentially and respectively. Between July 2002 and February 2004, 14 young male patients (aged 15-31 years)suffering from symptomatic lumbar spondylolysis were treated with TSRH hook screw fixation after direct repair of the defects. MacNab criteria1 were used to assess their preand post-operative status.Results: Each fixation technique could significantly increase the intervertebral rotational stiffness and made the stiffness return to nearly the intact level. Hook screw technique provided more rotational stability than the others. Hook screw and Buck's techniques provided more flexion/extension stability than modified Scott's technique.Neither complication nor instrumental failure was observed in this study. The mean follow-up period was 21 months.All the patients except one acquired union during the follow-up period. Thirteen patients had a "good" or "excellent" result according to MacNab criteria.Conclusions: Hook screw fixation shows biomechanical advantages and is safe and effective for young patients with lumbar spondylolysis.

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

    Directory of Open Access Journals (Sweden)

    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

  11. Patellofemoral anatomy and biomechanics.

    Science.gov (United States)

    Sherman, Seth L; Plackis, Andreas C; Nuelle, Clayton W

    2014-07-01

    Patellofemoral disorders are common. There is a broad spectrum of disease, ranging from patellofemoral pain and instability to focal cartilage disease and arthritis. Regardless of the specific condition, abnormal anatomy and biomechanics are often the root cause of patellofemoral dysfunction. A thorough understanding of normal patellofemoral anatomy and biomechanics is critical for the treating physician. Recognizing and addressing abnormal anatomy will optimize patellofemoral biomechanics and may ultimately translate into clinical success.

  12. Biomechanical Role of Bone Anisotropy Estimated on Clinical CT Scans by Image Registration.

    Science.gov (United States)

    Taghizadeh, Elham; Reyes, Mauricio; Zysset, Philippe; Latypova, Adeliya; Terrier, Alexandre; Büchler, Philippe

    2016-08-01

    Image-based modeling is a popular approach to perform patient-specific biomechanical simulations. Accurate modeling is critical for orthopedic application to evaluate implant design and surgical planning. It has been shown that bone strength can be estimated from the bone mineral density (BMD) and trabecular bone architecture. However, these findings cannot be directly and fully transferred to patient-specific modeling since only BMD can be derived from clinical CT. Therefore, the objective of this study was to propose a method to predict the trabecular bone structure using a µCT atlas and an image registration technique. The approach has been evaluated on femurs and patellae under physiological loading. The displacement and ultimate force for femurs loaded in stance position were predicted with an error of 2.5% and 3.7%, respectively, while predictions obtained with an isotropic material resulted in errors of 7.3% and 6.9%. Similar results were obtained for the patella, where the strain predicted using the registration approach resulted in an improved mean squared error compared to the isotropic model. We conclude that the registration of anisotropic information from of a single template bone enables more accurate patient-specific simulations from clinical image datasets than isotropic model.

  13. Kinect One-based biomechanical assessment of upper-limb performance compared to clinical scales in post-stroke patients.

    Science.gov (United States)

    Scano, Alessandro; Caimmi, Marco; Chiavenna, Andrea; Malosio, Matteo; Tosatti, Lorenzo Molinari

    2015-08-01

    This paper presents a Kinect One sensor-based protocol for the evaluation of the motor-performances of the upper limb of neurological patients during rehabilitative sessions. The assessment provides evaluations of kinematic, dynamic, motor and postural control variables. A pilot study was conducted on three post-stroke neurological patients, comparing Kinect-One biomechanical assessment with the outcomes of some of the most common clinical scales for the evaluation of the upper-limb functionality. Preliminary results indicate coherency between the clinical and instrumental evaluation. Moreover, the Kinect-One assessment seems to provide some complementary quantitative information, consistently integrating the clinical assessment.

  14. Hipbone Biomechanical Finite Element Analysis and Clinical Study after the Resection of Ischiopubic Tumors

    Institute of Scientific and Technical Information of China (English)

    Ya-qi He; Xue-lin Zhang; Bing-hang Tang; Ang Yang

    2012-01-01

    Objective To investigate the changes of hipbone biomechanics after the resection of ischiopubic tumors and their relationships with the complications in the convalescent stage,and directing the postoperative pelvic reconstruction.Methods DICOM data were used to create an intact hipbone finite element model and postoperative model.The biomechanical indices on the same region in the two models under the same boundary condition were compared.The differences of displacement,stress,and strain of the two models were analyzed with statistical methods.Results The distribution areas of the hipbone nodes' displacement,stress,and strain were similar before and after the simulated operation.The sacroiliac joint nodes' displacement (P=0.040) and strain (P=0.000),and the acetabular roof nodes' stress (P=0.000) and strain (P=0.005) of two models had signifi-cant differences,respectively.But the sacroiliac joint nodes' stress (P=0.076) and the greater sciatic notch nodes' stress (P=0.825) and strain (P=0.506) did not have significant differences.Conclusions The resection of ischiopubic tumors mainly affect the biomechanical states of the homolateral sacroiliac joint and acetabular roof.The complications in the convalescent stage are due to the biomechanical changes of the sacroiliac joint and the acetabular roof and disappearances of the stabilization and connection functions of the pubic symphysis and superior ramus of pubis.

  15. Fundamentals of Biomechanics

    OpenAIRE

    Duane Knudson

    2007-01-01

    DESCRIPTION This book provides a broad and in-depth theoretical and practical description of the fundamental concepts in understanding biomechanics in the qualitative analysis of human movement. PURPOSE The aim is to bring together up-to-date biomechanical knowledge with expert application knowledge. Extensive referencing for students is also provided. FEATURES This textbook is divided into 12 chapters within four parts, including a lab activities section at the end. The division is as follow...

  16. 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.

  17. Pharmacogenomics: from cell to clinic (Part 1).

    Science.gov (United States)

    Siest, Gérard; Medeiros, Rui; Melichar, Bohuslav; Stathopoulou, Maria; Van Schaik, Ron H N; Cacabelos, Ramon; Abt, Peter Meier; Monteiro, Carolino; Gurwitz, David; Queiroz, Jao; Mota-Filipe, Helder; Ndiaye, Ndieye Coumba; Visvikis-Siest, Sophie

    2014-04-01

    The second international European Society of Pharmacogenomics and Theranostics (ESPT) conference was organized in Lisbon, Portugal, and attracted 250 participants from 37 different countries. The participants could listen to 50 oral presentations, participate in five lunch symposia and were able to view 83 posters and an exhibition. The first part of this Conference Scene will focus on the pharmacogenomics and biomarkers used in medical oncology, and in particular solid tumors. In addition, this article covers the two keynote conference introductory lectures by Ann K Daly and Magnus Ingelman-Sundberg. The second part of this article will discuss the clinical implementation of pharmacogenomic tests; the role of transports and pharmacogenomics; how stem cells and other new tools are helping the development of pharmacogenomics and drug discovery; and an update on the clinical translation of pharmacogenomics to personalized medicine. Part two of this Conference Scene will be featured in the next issue of Pharmacogenomics.

  18. 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.

  19. Osteoarthritis in horses - Part 1: relationship between clinical and radiographic examination for the diagnosis

    Directory of Open Access Journals (Sweden)

    Maria Verônica de Souza

    Full Text Available ABSTRACT Locomotor disorders are very common in the equine clinic, which may be partly due to the different types of activities horses develop. Osteoarthritis (OA, commonly known as degenerative joint disease, presents an considerable role in the series of disorders of the musculoskeletal system and may be associated with other problems such as navicular syndrome, periostitis or osteochondrosis. This affection causes progressive deterioration of articular cartilage, accompanied by bone and soft-tissue periarticular changes. In fact, it results from a complex interaction between biochemical and biomechanical factors. The objective of this article is to review information about clinical and radiographic findings of OA, the biochemical and biomechanical changes manifested in the disease and the importance of the synovial fluid. Additionally, some information on other species is also presented. This review refers to Part 1 of a study whose sequence is entitled "Osteoarthritis in horses - Part 2: a review of the intra-articular use of corticosteroids as a method of treatment."

  20. 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.

  1. Corneal biomechanics: a review.

    Science.gov (United States)

    Piñero, David P; Alcón, Natividad

    2015-03-01

    Biomechanics is often defined as 'mechanics applied to biology'. Due to the variety and complexity of the behaviour of biological structures and materials, biomechanics is better defined as the development, extension and application of mechanics for a better understanding of physiology and physiopathology and consequently for a better diagnosis and treatment of disease and injury. Different methods for the characterisation of corneal biomechanics are reviewed in detail, including those that are currently commercially available (Ocular Response Analyzer and CorVis ST). The clinical applicability of the parameters provided by these devices are discussed, especially in the fields of glaucoma, detection of ectatic disorders and orthokeratology. Likewise, other methods are also reviewed, such as Brillouin microscopy or dynamic optical coherence tomography and others with potential application to clinical practice but not validated for in vivo measurements, such as ultrasonic elastography. Advantages and disadvantages of all these techniques are described. Finally, the concept of biomechanical modelling is revised as well as the requirements for developing biomechanical models, with special emphasis on finite element modelling.

  2. Anterior cruciate ligament biomechanics during robotic and mechanical simulations of physiologic and clinical motion tasks: a systematic review and meta-analysis.

    Science.gov (United States)

    Bates, Nathaniel A; Myer, Gregory D; Shearn, Jason T; Hewett, Timothy E

    2015-01-01

    Investigators use in vitro joint simulations to invasively study the biomechanical behaviors of the anterior cruciate ligament. The aims of these simulations are to replicate physiologic conditions, but multiple mechanisms can be used to drive in vitro motions, which may influence biomechanical outcomes. The objective of this review was to examine, summarize, and compare biomechanical evidence related to anterior cruciate ligament function from in vitro simulations of knee motion. A systematic review was conducted (2004 to 2013) in Scopus, PubMed/Medline, and SPORTDiscus to identify peer-reviewed studies that reported kinematic and kinetic outcomes from in vitro simulations of physiologic or clinical tasks at the knee. Inclusion criteria for relevant studies were articles published in English that reported on whole-ligament anterior cruciate ligament mechanics during the in vitro simulation of physiologic or clinical motions on cadaveric knees that were unaltered outside of the anterior-cruciate-ligament-intact, -deficient, and -reconstructed conditions. A meta-analysis was performed to synthesize biomechanical differences between the anterior-cruciate-ligament-intact and reconstructed conditions. 77 studies met our inclusion/exclusion criteria and were reviewed. Combined joint rotations have the greatest impact on anterior cruciate ligament loads, but the magnitude by which individual kinematic degrees of freedom contribute to ligament loading during in vitro simulations is technique-dependent. Biomechanical data collected in prospective, longitudinal studies corresponds better with robotic-manipulator simulations than mechanical-impact simulations. Robotic simulation indicated that the ability to restore intact anterior cruciate ligament mechanics with anterior cruciate ligament reconstructions was dependent on loading condition and degree of freedom examined.

  3. Mystery of alar ligament rupture: Value of MRI in whiplash injuries - biomechanical, anatomical and clinical studies; Mysterium Ligamentum alare Ruptur: Stellenwert der MRT-Diagnostik des Schleudertraumas - biomechanische, anatomische und klinische Studien

    Energy Technology Data Exchange (ETDEWEB)

    Bitterling, H.; Brueckmann, H. [Abt. fuer Neuroradiologie, Klinikum der LMU, Muenchen (Germany); Staebler, A. [Radiologische Praxis, Radiologie in Muenchen, Harlaching (Germany)

    2007-11-15

    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.)

  4. 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.

  5. Disadvantages of Balloon Kyphoplasty with PMMA - a Clinical and Biomechanical Statement

    Directory of Open Access Journals (Sweden)

    Becker S

    2011-01-01

    Full Text Available Balloon kyphoplasty (BKP and vertebroplasty (VP are clinically effective procedures. However, BKP has been occasionally associated with failure, although the cause has not been established thus far. We believe that, especially in patients with severe osteoporosis and osteonecrosis, BKP fails due to the so-called stress shielding effect and the stiffness of cement. In these patients, other bone-preserving kyphoplastic procedures and vertebroplasty, as well as recently introduced cements adjusted to the severity of osteoporosis, might be beneficial. Furthermore, it is essential to achieve complete straightening intraoperatively when performing BKP, because any persistent residual kyphosis will aggravate the burden on the adjacent vertebral bodies following the creation of a cavity filled with cement. Therefore, it would be meaningful to consider alternative bone-preserving kyphoplastic measures instead of BKP. In cases of older fractures, one should consider the use of VP and the recently introduced cements.

  6. 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.

  7. Biomechanical gait features associated with hip osteoarthritis: Towards a better definition of clinical hallmarks.

    Science.gov (United States)

    Meyer, Christophe A G; Corten, Kristoff; Fieuws, Steffen; Deschamps, Kevin; Monari, Davide; Wesseling, Mariska; Simon, Jean-Pierre; Desloovere, Kaat

    2015-10-01

    Critical appraisal of the literature highlights that the discriminative power of gait-related features in patients with hip osteoarthritis (OA) has not been fully explored. We aimed to reduce the number of gait-related features and define the most discriminative ones comparing the three-dimensional gait analysis of 20 patients with hip osteoarthritis (OA) with those of 17 healthy peers. First, principal component analysis was used to reduce the high-dimensional gait data into a reduced set of interpretable variables for further analysis, including tests for group differences. These differences were indicative for the selection of the top 10 variables to be included into linear discriminant analysis models (LDA). Our findings demonstrated the successful data reduction of hip osteoarthritic-related gait features with a high discriminatory power. The combination of the top variables into LDA models clearly separated groups, with a maximum misclassification error rate of 19%, estimated by cross-validation. Decreased hip/knee extension, hip flexion and internal rotation moment were gait features with the highest discriminatory power. This study listed the most clinically relevant gait features characteristics of hip OA. Moreover, it will help clinicians and physiotherapists understand the movement pathomechanics related to hip OA useful in the management and design of rehabilitation intervention.

  8. Modern scleral lenses part I: clinical features.

    NARCIS (Netherlands)

    Visser, E.S.; Visser, R.; Lier, H.J.J. van; Otten, H.M.

    2007-01-01

    PURPOSE: To evaluate the indications for modern scleral lenses and their clinical performance in patients who were fitted with scleral lenses at the authors' practices. METHODS: In this cross-sectional survey, all the necessary data were obtained at the first follow-up visit during the 5-month study

  9. Dinosaur biomechanics

    OpenAIRE

    Alexander, R. McNeill

    2006-01-01

    Biomechanics has made large contributions to dinosaur biology. It has enabled us to estimate both the speeds at which dinosaurs generally moved and the maximum speeds of which they may have been capable. It has told us about the range of postures they could have adopted, for locomotion and for feeding, and about the problems of blood circulation in sauropods with very long necks. It has made it possible to calculate the bite forces of predators such as Tyrannosaurus, and the stresses they imp...

  10. Clinical issues in occlusion - Part II.

    Science.gov (United States)

    Patel, Mahul; Alani, Aws

    2015-12-01

    Occlusal diagnosis plays an important role in the planning and subsequent delivery of predictable functional and aesthetic restorations and prostheses. Once an occlusal problem is identified there are a number of techniques and materials that can be utilised to record occlusal relationships, subsequently analyse them and incorporate information obtained into the delivery of tooth restoration or replacement. This paper discusses the clinical and technical aspects of occlusal examination and analysis outlining contemporary and traditional techniques in their utilisation. Aspects of occlusal examination will be revisited; the identification and recording of centric occlusion as well as subsequent articulation will be discussed. The requirement for occlusal splint provision will also be discussed and illustrated.

  11. Biomechanical Evaluation of Different Fixation Methods for Mandibular Anterior Segmental Osteotomy Using Finite Element Analysis, Part Two: Superior Repositioning Surgery With Bone Allograft.

    Science.gov (United States)

    Kilinç, Yeliz; Erkmen, Erkan; Kurt, Ahmet

    2016-01-01

    In this study, the biomechanical behavior of different fixation methods used to fix the mandibular anterior segment following various amounts of superior repositioning was evaluated by using Finite Element Analysis (FEA). The three-dimensional finite element models representing 3 and 5 mm superior repositioning were generated. The gap in between segments was assumed to be filled by block bone allograft and resignated to be in perfect contact with the mandible and segmented bone. Six different finite element models with 2 distinct mobilization rate including 3 different fixation configurations, double right L (DRL), double left L (DLL), or double I (DI) miniplates with monocortical screws, correspondingly were created. A comparative evaluation has been made under vertical, horizontal and oblique loads. The von Mises and principal maximum stress (Pmax) values were calculated by finite element solver programme. The first part of our ongoing Finite Element Analysis research has been addressed to the mechanical behavior of the same fixation configurations in nongrafted models. In comparison with the findings of the first part of the study, it was concluded that bone graft offers superior mechanical stability without any limitation of mobilization and less stress on the fixative appliances as well as in the bone.

  12. 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.

  13. Dinosaur biomechanics.

    Science.gov (United States)

    Alexander, R McNeill

    2006-08-07

    Biomechanics has made large contributions to dinosaur biology. It has enabled us to estimate both the speeds at which dinosaurs generally moved and the maximum speeds of which they may have been capable. It has told us about the range of postures they could have adopted, for locomotion and for feeding, and about the problems of blood circulation in sauropods with very long necks. It has made it possible to calculate the bite forces of predators such as Tyrannosaurus, and the stresses they imposed on its skull; and to work out the remarkable chewing mechanism of hadrosaurs. It has shown us how some dinosaurs may have produced sounds. It has enabled us to estimate the effectiveness of weapons such as the tail spines of Stegosaurus. In recent years, techniques such as computational tomography and finite element analysis, and advances in computer modelling, have brought new opportunities. Biomechanists should, however, be especially cautious in their work on animals known only as fossils. The lack of living specimens and even soft tissues oblige us to make many assumptions. It is important to be aware of the often wide ranges of uncertainty that result.

  14. 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.

  15. 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)

  16. Biomechanics in dermatology: Recent advances and future directions.

    Science.gov (United States)

    Lewinson, Ryan T; Haber, Richard M

    2017-02-01

    Biomechanics is increasingly being recognized as an important research area in dermatology. To highlight only a few examples, biomechanics has contributed to the development of novel topical therapies for aesthetic and medical purposes, enhanced our understanding of the pathogenesis of plantar melanoma, and provided insight into the epidemiology of psoriatic disease. This article summarizes the findings from recent studies to demonstrate the important role that biomechanics may have in dermatologic disease and therapy and places these biomechanical findings in a clinical context for the practicing physician. In addition, areas for future biomechanics research and development in dermatology are discussed.

  17. 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…

  18. 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.

  19. 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...

  20. The Use of Bone Age in Clinical Practice - Part 1

    NARCIS (Netherlands)

    D.D. Martin; J.M. Wit; Z.E. Hochberg; L. Sävendahl; R.R. van Rijn; O. Fricke; N. Cameron; J. Caliebe; T. Hertel; D. Kiepe; K. Albertsson-Wikland; H.H. Thodberg; G. Binder; M.B. Ranke

    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 addressed

  1. Clinical transformation of ankle joint biomechanics analyzed by three-dimensional finite element%踝关节三维有限元生物力学研究的临床转化

    Institute of Scientific and Technical Information of China (English)

    郭鹏超; 王成伟

    2014-01-01

      结果与结论:踝关节生物力学机制复杂,各种损伤后都可能打破其周围结构的力学平衡而导致不稳定,诱发创伤性关节炎。踝关节三维有限元模型可准确反映解剖学结构特点、虚拟仿真可以再现手术方式及过程逼真的模拟,模拟压缩、拉伸、弯曲、扭转、抗疲劳等力学实验,并从静态的生物力学转向动态的方向研究,为分析临床疾病进而找到更合适的诊治方案。%BACKGROUND:Ankle joint is a center of body weight, foot pressure buffering and human contact with the ground and easily gets injury. The study of orthopedic biomechanics continues to mature and develop. Models were established with three-dimensional finite element software to analyze ankle biomechanics and to study clinical diseases, which gradual y become a hot research topic. OBJECTIVE:To investigate the current status of three-dimensional finite element analysis of biomechanics in the ankle and to review the clinical research progress. METHODS:China National Knowledge Infrastructure and PubMed (from January 1986 to March 2014) were used to search the related finite element articles about ankle. The retrieval words included ankle, finite element, biomechanics and mechanics research. After excluding objective-independent papers or repeated articles, 47 papers were included for further analysis. RESULTS AND CONCLUSION:Ankle joint complex biomechanics mechanism and variety of injury could break mechanics balance of its surrounding structure and lead to instability and traumatic arthritis. Ankle’s three-dimensional finite element model can accurately reflect anatomical structure and virtual simulation can reappear the operation method in the simulation biomechanics experiment, such as compression, tension, bending, torsion and anti-fatigue mechanics. It makes the direction of the research from biomechanics of static to dynamic, which finds a more suitable solution to diagnose and treat

  2. 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

  3. 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

  4. Conference scene: pharmacogenomics: from cell to clinic (part 2).

    Science.gov (United States)

    Siest, Gérard; Medeiros, Rui; Melichar, Bohuslav; Stathopoulou, Maria; Van Schaik, Ron Hn; Cacabelos, Ramon; Abt, Peter Meier; Monteiro, Carolino; Gurwitz, David; Queiroz, Jao; Mota-Filipe, Helder; Ndiaye, Ndeye Coumba; Visvikis-Siest, Sophie

    2014-04-01

    Second International ESPT Meeting Lisbon, Portugal, 26-28 September 2013 The second European Society of Pharmacogenomics and Theranostics (ESPT) conference was organized in Lisbon, Portugal, and attracted 250 participants from 37 different countries. The participants could listen to 50 oral presentations, participate in five lunch symposia and were able to view 83 posters and an exhibition. Part 1 of this Conference Scene was presented in the previous issue of Pharmacogenomics. This second part will focus on: clinical implementation of pharmacogenomics tests; transporters and pharmacogenomics; stem cells and other new tools for pharmacogenomics and drug discovery; from system pharmacogenomics to personalized medicine; and, finally, we will discuss the Posters and Awards that were presented at the conference.

  5. A multiscale model for the study of cardiac biomechanics in single-ventricle surgeries: a clinical case.

    Science.gov (United States)

    Meoli, Alessio; Cutrì, Elena; Krishnamurthy, Adarsh; Dubini, Gabriele; Migliavacca, Francesco; Hsia, Tain-Yen; Pennati, Giancarlo; Taylor, Andrew; Giardini, Alessandro; Khambadkone, Sachin; Schievano, Silvia; de Leval, Marc; Hsia, T-Y; Bove, Edward; Dorfman, Adam; Baker, G Hamilton; Hlavacek, Anthony; Migliavacca, Francesco; Pennati, Giancarlo; Dubini, Gabriele; Marsden, Alison; Feinstein, Jeffrey; Vignon-Clementel, Irene; Figliola, Richard; McGregor, John

    2015-04-06

    Complex congenital heart disease characterized by the underdevelopment of one ventricular chamber (single ventricle (SV) circulation) is normally treated with a three-stage surgical repair. This study aims at developing a multiscale computational framework able to couple a patient-specific three-dimensional finite-element model of the SV to a patient-specific lumped parameter (LP) model of the whole circulation, in a closed-loop fashion. A sequential approach was carried out: (i) cardiocirculatory parameters were estimated by using a fully LP model; (ii) ventricular material parameters and unloaded geometry were identified by means of the stand-alone, three-dimensional model of the SV; and (iii) the three-dimensional model of SV was coupled to the LP model of the circulation, thus closing the loop and creating a multiscale model. Once the patient-specific multiscale model was set using pre-operative clinical data, the virtual surgery was performed, and the post-operative conditions were simulated. This approach allows the analysis of local information on ventricular function as well as global parameters of the cardiovascular system. This methodology is generally applicable to patients suffering from SV disease for surgical planning at different stages of treatment. As an example, a clinical case from stage 1 to stage 2 is considered here.

  6. 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.

  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. Biomechanically Engineered Athletes.

    Science.gov (United States)

    Perry, Tekla S.

    1991-01-01

    The real-world meeting of electronics, computer monitoring, control systems, and mathematics, introduced in the context of sports, is described. Recent advances in the field of biomechanics and its use in improving athletic performance are discussed. (KR)

  9. 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.

  10. Comparative Analysis between Total Disc Replacement and Posterior Foraminotomy for Posterolateral Soft Disc Herniation with Unilateral Radiculopathy : Clinical and Biomechanical Results of a Minimum 5 Years Follow-up

    Science.gov (United States)

    Kim, Kyoung-Tae; Cho, Dae-Chul; Sung, Joo-Kyung; Kim, Young-Baeg; Kim, Du Hwan

    2017-01-01

    Objective To compare the clinical outcomes and biomechanical effects of total disc replacement (TDR) and posterior cervical foraminotomy (PCF) and to propose relative inclusion criteria. Methods Thirty-five patients who underwent surgery between 2006 and 2008 were included. All patients had single-level disease and only radiculopathy. The overall sagittal balance and angle and height of a functional segmental unit (FSU; upper and lower vertebral body of the operative lesion) were assessed by preoperative and follow-up radiographs. C2–7 range of motion (ROM), FSU, and the adjacent segment were also checked. Results The clinical outcome of TDR (group A) was tended to be superior to that of PCF (group B) without statistical significance. In the group A, preoperative and postoperative upper adjacent segment level motion values were 8.6±2.3 and 8.4±2.0, and lower level motion values were 8.4±2.2 and 8.3±1.9. Preoperative and postoperative FSU heights were 37.0±2.1 and 37.1±1.8. In the group B, upper level adjacent segment motion values were 8.1±2.6 and 8.2±2.8, and lower level motion values were 6.5±3.3 and 6.3±3.1. FSU heights were 37.1±2.0 and 36.2±1.8. The postoperative FSU motion and height changes were significant (p<0.05). The patient’s satisfaction rates for surgery were 88.2% in group A and 88.8% in group B. Conclusion TDR and PCF have favorable outcomes in patients with unilateral soft disc herniation. However, patients have different biomechanical backgrounds, so the patient’s biomechanical characteristics and economic status should be understood and treated using the optimal procedure. PMID:28061490

  11. 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 composite and 129 MPa for metal-plated femurs at the vicinity of nearest screw just proximal to fracture (stage 3), 21 MPa for composite and 24 MPa for metal

  12. Biomechanics and the wheelchair.

    Science.gov (United States)

    McLaurin, C A; Brubaker, C E

    1991-04-01

    Wheelchair biomechanics involves the study of how a wheelchair user imparts power to the wheels to achieve mobility. Because a wheelchair can coast, power input need not be continuous, but each power strike can be followed by a period of recovery, with the stroking frequency depending on user preferences and the coasting characteristics of the wheelchair. The latter is described in terms of rolling resistance, wind resistance and the slope of the surface. From these three factors the power required to propel the wheelchair is determined, and must be matched by the power output of the user. The efficiency of propulsion is the ratio of this power output to the metabolic cost and is typically in the order of 5% in normal use. The features required in a wheelchair depend upon user characteristics and intended activities. The ideal wheelchair for an individual will have the features that closely match these characteristics and activities. Thus prescription is not just choosing a wheelchair, but choosing the components of the wheelchair that best serve the intended purpose. In this paper, each component is examined for available options and how these options effect the performance of the wheelchair for the individual. The components include wheels, tyres, castors, frames, bearings, materials, construction details, seats, backrests, armrests, foot and legrests, headrests, wheel locks, running brakes, handrims, levers, accessories, adjustments and detachable parts. Each component is considered in relation to performance characteristics including rolling resistance, versatility, weight, comfort, stability, maneouvrability, transfer, stowage, durability and maintenance. Where they exist, wheelchair standards are referred to as a source of information regarding these characteristics.

  13. Hansson Pin 治疗股骨颈骨折的生物力学测试与临床应用分析%Biomechanical Experiment and Clinical Application of Hansson Pin for the Treatment of Femoral Neck Fracture

    Institute of Scientific and Technical Information of China (English)

    林博文; 肖德明; 黎伟凡; 麦汉溪; 朱杰诚; 曾纪葵

    2001-01-01

    目的 探讨HanssonPin治疗股骨颈骨折的疗效。方法 临床治疗39例,并作生物力学测试。结果 全部病例得到随访,时间4~36个月,平均23个月。骨性愈合31例,其中12例有滑针、股骨颈缩短表现,半年内出现滑针、塌陷移位3例;股骨头缺血性坏死5例。生物力学性能显示HanssonPin的承力效果优于骨圆针。结论 HanssonPin作为股骨颈内固定操作简单,但术后早期负重行走滑针率较高。%Objective To investigate the clinical therapeatic effectivenessof the femoral neck fracture treated by Hansson pin and biomechanical test was carried out in cadaveri femoral specimens.Methods Thirty-nine cases of femoral neck fracture were treated by Hansson Pin and biomechanical test was carried out in cadaveri femoral specimens.Results All patients were foll owed up for an average duration of 23 months.The results show that 31 cases healed up, as a result of pins sliding, so that femoral neck was shortening in 12 cases; femoral head collapsed was found in 3 cases and ischemic necrosis of femoral head appeared in 5 cases . The biomechanical character of Hansson pin is only better than round pin.Conclusion Hansson pinis easy to be used , but the rate of sliding pin is 38.46%,which is resulted from allowing the patient to wear early

  14. 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...... recessions. Gingival recession is a problem often in the region of the lower incisors. A micro-CT study on human autopsy material, performed at the University of Aarhus, confirmed that the anterior mandibular alveolar envelope is indeed very thin. The prognosis of a gingival recession can be improved...

  15. Biomechanical response of the pediatric abdomen, part 1: development of an experimental model and quantification of structural response to dynamic belt loading.

    Science.gov (United States)

    Kent, Richard; Stacey, Stephen; Kindig, Matthew; Forman, Jason; Woods, William; Rouhana, Stephen W; Higuchi, Kazuo; Tanji, Hiromasa; Lawrence, Schuyler St; Arbogast, Kristy B

    2006-11-01

    The abdomen is the second most commonly injured region in children using adult seat belts, but engineers are limited in their efforts to design systems that mitigate these injuries since no current pediatric dummy has the capability to quantify injury risk from loading to the abdomen. This paper develops a porcine (sus scrofa domestica) model of the 6-year-old human's abdomen, and then defines the biomechanical response of this abdominal model. First, a detailed abdominal necropsy study was undertaken, which involved collecting a series of anthropometric measurements and organ masses on 25 swine, ranging in age from 14 to 429 days (4-101 kg mass). These were then compared to the corresponding human quantities to identify the best porcine representation of a 6-year-old human's abdomen. This was determined to be a pig of age 77 days, and whole-body mass of 21.4 kg. The sub-injury, quasistatic response to belt loading of this porcine model compared well with pediatric human volunteer tests performed with a lap belt on the lower abdomen. A test fixture was designed to produce transverse, dynamic belt loading on the porcine abdomen. A detailed review of field cases identified the following test variables: loading location (upper/lower), penetration magnitude (23%-68% of initial abdominal depth), muscle tensing (yes/no), and belt penetration rate (quasistatic, dynamic 2.9 m/s - 7.8 m/s). Dynamic tests were performed on 47 post-mortem subjects. Belt tension and dorsal reaction force were cross-plotted with abdominal penetration to generate structural response corridors. Subcutaneous stimulation of the anterior abdominal muscle wall stiffened the quasistatic response significantly, but was of negligible importance in the dynamic tests. The upper abdomen exhibited stiffer response quasistatically, and also was more sensitive to penetration rate, with stiffness increasing significantly over the range of dynamic rates tested here. In contrast, the lower abdomen was relatively

  16. Mobile clinics in Haiti, part 2: Lessons learned through service.

    Science.gov (United States)

    Haley, Janice M; Cone, Pamela H

    2016-11-01

    Learning from experience is a positive approach when preparing for mobile clinic service in a developing country. Mobile clinics provide healthcare services to people in hard to reach areas around the world, but preparation for their use needs to be done in collaboration with local leaders and healthcare providers. For over 16 years, Azusa Pacific University School of Nursing has sponsored mobile clinics to rural northern Haiti with the aim to provide culturally sensitive healthcare in collaboration with Haitian leaders. Past Haiti mobile clinic experiences have informed the APU-SON approach on best practices in study abroad, service-learning, and mission trips providing healthcare services. Hopefully, lessons learned from these experiences with mobile clinic service-learning opportunities in Haiti will benefit others who seek to plan study abroad service-learning trips for students in healthcare majors who desire to serve the underserved around the world.

  17. Which Parts of a Clinical Process EPR Needs Special Configuration

    DEFF Research Database (Denmark)

    Barlach, Anders; Simonsen, Jesper

    2007-01-01

    Subject: Which parts of an electronic patient record (EPR) can initially form a stable standard solution to be used by all clinicians? And which parts of an EPR can we predict needs initial as well as on-going re-configuration to meet the needs from diverse medical specialties. Purpose: To analyz...

  18. Implementing clinical supervision: Part 1: laying the ground work.

    Science.gov (United States)

    Lynch, Lisa; Happell, Brenda

    2008-02-01

    Australia, like other countries, is experiencing a crisis in the recruitment and retention of nurses. Clinical supervision has been suggested as a potential strategy to enhance retention. However, there is a paucity of literature regarding the successful implementation of clinical supervision. The aim of this study is to explore and evaluate ways of implementing clinical supervision as undertaken in a rural health-care organization in Victoria. Qualitative methodology was used including a documentation audit and individual interviews with the staff responsible for implementation. The findings demonstrate that the successful implementation had occurred in five interrelated stages. This paper, one in a series of three, focuses on the preimplementation phase leading up to initial implementation. The main themes identified during these stages were: organizational culture, exploring the possibilities, leadership and education and training which will be examined. These issues were essential in laying the foundation for the systematic introduction of clinical supervision.

  19. Risk management in clinical practice. Part 10. Periodontology.

    Science.gov (United States)

    Baker, P; Needleman, I

    2010-12-11

    A sizeable proportion of patients in clinical practice will have some form of periodontal disease and most of these patients can be well managed in primary care. Unfortunately, dento-legal claims regarding inappropriate periodontal care are increasing rapidly and are now one of the most common reasons for litigation in dentistry. In this paper we will look at aspects of contemporary management of periodontal disease in clinical practice and offer guidance for examination, management and referral.

  20. Biomechanics of foetal movement.

    Science.gov (United States)

    Nowlan, N C

    2015-01-02

    Foetal movements commence at seven weeks of gestation, with the foetal movement repertoire including twitches, whole body movements, stretches, isolated limb movements, breathing movements, head and neck movements, jaw movements (including yawning, sucking and swallowing) and hiccups by ten weeks of gestational age. There are two key biomechanical aspects to gross foetal movements; the first being that the foetus moves in a dynamically changing constrained physical environment in which the freedom to move becomes increasingly restricted with increasing foetal size and decreasing amniotic fluid. Therefore, the mechanical environment experienced by the foetus affects its ability to move freely. Secondly, the mechanical forces induced by foetal movements are crucial for normal skeletal development, as evidenced by a number of conditions and syndromes for which reduced or abnormal foetal movements are implicated, such as developmental dysplasia of the hip, arthrogryposis and foetal akinesia deformation sequence. This review examines both the biomechanical effects of the physical environment on foetal movements through discussion of intrauterine factors, such as space, foetal positioning and volume of amniotic fluid, and the biomechanical role of gross foetal movements in human skeletal development through investigation of the effects of abnormal movement on the bones and joints. This review also highlights computational simulations of foetal movements that attempt to determine the mechanical forces acting on the foetus as it moves. Finally, avenues for future research into foetal movement biomechanics are highlighted, which have potential impact for a diverse range of fields including foetal medicine, musculoskeletal disorders and tissue engineering.

  1. Biomechanics of foetal movement

    Directory of Open Access Journals (Sweden)

    N.C. Nowlan

    2015-01-01

    Full Text Available Foetal movements commence at seven weeks of gestation, with the foetal movement repertoire including twitches, whole body movements, stretches, isolated limb movements, breathing movements, head and neck movements, jaw movements (including yawning, sucking and swallowing and hiccups by ten weeks of gestational age. There are two key biomechanical aspects to gross foetal movements; the first being that the foetus moves in a dynamically changing constrained physical environment in which the freedom to move becomes increasingly restricted with increasing foetal size and decreasing amniotic fluid. Therefore, the mechanical environment experienced by the foetus affects its ability to move freely. Secondly, the mechanical forces induced by foetal movements are crucial for normal skeletal development, as evidenced by a number of conditions and syndromes for which reduced or abnormal foetal movements are implicated, such as developmental dysplasia of the hip, arthrogryposis and foetal akinesia deformation sequence. This review examines both the biomechanical effects of the physical environment on foetal movements through discussion of intrauterine factors, such as space, foetal positioning and volume of amniotic fluid, and the biomechanical role of gross foetal movements in human skeletal development through investigation of the effects of abnormal movement on the bones and joints. This review also highlights computational simulations of foetal movements that attempt to determine the mechanical forces acting on the foetus as it moves. Finally, avenues for future research into foetal movement biomechanics are highlighted, which have potential impact for a diverse range of fields including foetal medicine, musculoskeletal disorders and tissue engineering.

  2. [Juvenil idiopathic arthritis. Part 1: diagnosis, pathogenesis and clinical manifestations].

    Science.gov (United States)

    Espada, Graciela

    2009-10-01

    Juvenile idiopathic arthritis is not a single disease and constitutes an heterogeneous group of illnesses or inflammatory disorders. This new nomenclature encompasses different disease categories, each of which has different presentation, clinical signs, symptoms, and outcome. The cause of the disease is still unknown but both environmental and genetic factors seem to be related to its pathogenesis. Is the most common chronic rheumatic disease in children and an important cause of short-term and long-term disability. In this article, clinical manifestation, new classification and approach to diagnosis are reviewed.

  3. Clinical applications of imaging biomarkers. Part 1. The neuroradiologist's perspective

    OpenAIRE

    Smith, E T S

    2011-01-01

    This article is concerned with the application and usage in clinical practice of techniques of detection and measurement of imaging biomarkers. Some commentaries in the article derive from a literature search and include summaries of recently published material compiled and linked to each other by extensive use of the text contained in the material examined.

  4. Mechanisms of electrode induced injury. Part 2: Clinical experience.

    Science.gov (United States)

    Patterson, Terry; Stecker, Mark M; Netherton, Brett L

    2007-06-01

    In the previous paper in this series, basic mechanisms of electrode related injuries were discussed. In this paper, the discussion begins with some of the clinical aspects of burns. This is followed by a summary of the clinical literature on injuries produced by surface and subdermal electrodes. This clinical literature demonstrates that most electrode burns are related to the presence of high frequency electric fields (RF) created either by an electrosurgical unit or a magnetic resonance imaging (MRI) scanner. A smaller number of lesions are produced by low current, long duration direct current (DC) stimulation and during high current stimulation such as defibrillation. A discussion of the clinical complications from indwelling intracranial electrodes centers on electrodes placed for deep brain stimulation (DBS) that are currently used therapeutically in a wide array of neurologic disorders. The probability of considering a post-implant MRI scan is high and the safety of such scans is the focus of discussion. A very small number of adverse incidents have indicated a downward revision in the specific absorption rate recommendations for MRI examination with those patients who present with indwelling DBS leads and internal pulse generators. Continued vigilance when any type of electrode is used is important.

  5. Biomechanical Analysis of Outstanding Female Race-walkers' Part of Technical Characteristics%优秀女竞走运动员部分技术特征的生物力学分析

    Institute of Scientific and Technical Information of China (English)

    李小生

    2013-01-01

    Part of the biomechanical characteristics of outstanding female race-walkers' techniques is gained through plane machine setting photography and it is found that whether individuals or groups, the change value dispersion degree of outstanding 20 km race walkers in China is quite high which should be improved in training. It is suggested that the walkers speed up the pace on the basis of mixed reasonable stable step length so as to enhance athletic performance.%  通过平面定机摄影获得优秀女子竞走队员竞走技术的部分生物力学特征。发现我国优秀女子20km竞走运动员不论是个体还是群体其变化值离散程度均较高,训练中应当加以改进。建议在固定合理稳定的步长基础上加快步频,从而提高运动成绩。

  6. 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

  7. 人工种植牙修复牙列缺损的疗效及生物力学研究%Clinical effect and biomechanical research of dental implant in the restoration of dentition defect

    Institute of Scientific and Technical Information of China (English)

    陈增芳

    2013-01-01

    Objective To observe the clinical effect of dental implant system in the dentition defect repair,and to explore biomechanical properties of instant axial and lateral load to dental implants.Methods Forty-two patients with dentition defect received 67 ITI Straumann dental implants,6 months after which the upper part of the plant was repaired.Three-dimensional finite element models were established to analyze stress changes for dental implants with different immediate loadings.Results Twelve months after planting,94.0% (63/67) dental implants were planted successfully,and the rest of the indicators are good.Both in axial and lateral loads,stress was concentrated in the neck of the implant,stress of middle and apical parts decrease gradually.In 10 °,20 ° and 30 ° lateral load,at the part of 1/3 neck stress dropped sharply,and with the lateral load inclination increase,the neck stress increased.Conclusion Dental implant is an excellent method for repairing defective dentition with satisfactory results.Dental implant is applicable,but dentists should pay attention to the anastomosis angle,to avoid dental implant and foundation piles subject to lateral forces,in order to guarantee satisfying success rate of dental implants.%目的 观察人工种植牙修复牙列缺损的临床效,探讨牙种植体轴向和侧向即刻负载时的生物力学性能.方法 42例牙列缺损患者,共植入ITI Straumann牙种植体67枚,6个月后行种植义齿修复.采用三维有限元法分析种植牙即刻负载时不同负载下种植体骨界面的应力及位移变化.结果 修复后12个月,种植成功率为94.0%(63/67),其余各项指标良好.种植体轴向及侧向负载时,应力均集中在颈部,中部和根尖区应力逐渐较小;10°、20°及30°侧向负载时,颈1/3处落差较大,且随着侧向负载倾斜度增加,颈部应力增大.侧向负载时种植体的即刻负载位移均明显大于轴向负载位移(P<0.05),且种植体的即刻负载

  8. Risk management in clinical practice. Part 4. Endodontics.

    Science.gov (United States)

    Webber, J

    2010-08-28

    Endodontic procedures are challenging and technically demanding. In the UK standards of treatment have been shown to have fallen short of acceptable guidelines, laying many dentists open to litigation on questions of clinical negligence by patients who understand and know what should be considered as current best practice in this area. Failure to communicate with patients about the procedure and not obtaining consent for treatment is a key area of complaint, as is inadequate record keeping. When treatment is undertaken within the framework of accepted guidelines it would be very difficult for a patient to open a claim for clinical negligence should a failure occur. This article looks at potential dento-legal problems in endodontics and how, through compliance with best practice, they may be avoided.

  9. Anatomy and biomechanics of the elbow joint.

    Science.gov (United States)

    Martin, Silvia; Sanchez, Eugenia

    2013-11-01

    Magnetic resonance (MR) imaging provides clinically useful information in assessing the elbow joint. Superior depiction of muscles, ligaments and tendons as well as the ability to directly visualize nerves, bone marrow and hyaline cartilage, are advantages of MR imaging relative to conventional imaging techniques. As the elbow is located superficially, clinical examination is easier for the orthopedic surgeon and only a few cases need a diagnosis for the radiologist, for this reason the elbow joint is little known for the radiologist. To better understand the injuries that occur in the elbow during the sport activities, we need a better understanding of the biomechanics of the joint. And for understanding the biomechanics, it is necessary to know the exact anatomy of the elbow joint and to be able to identify each anatomic structure in the different imaging planes and pulse sequences. This is especially important in MR as the imaging tool that shows a highest soft tissue resolution among other imaging techniques.

  10. The Effect of Chang Run Tong on Biomechanical Colon Remodeling in STZ-Induced Type I Diabetic Rats - Is It Related to Advanced Glycation End Product Formation?

    DEFF Research Database (Denmark)

    Zhao, Jingbo; Gregersen, Hans

    2015-01-01

    BACKGROUND AND AIM: The Chinese medicine Chang Run Tong (CRT) effectively improved senile constipation in the clinics. The aims of the present study were to investigate the effect of CRT on colonic remodeling in streptozotocin (STZ) induced diabetic rats and to explore the mechanisms of the CRT...... regression analysis was done to study association between AGE/RAGE expression with the histomorphometric and biomechanical parameters. RESULTS: The wet weight per unit length to body weight ratio, wall thickness, the cross-sectional wall area,opening angle and absolute values of inner and outer residual...... and biomechanical remodeling parameters. The AGE/RAGE expressions were significantly decreased in the T1 group (P0.05). CONCLUSIONS:CRT (high dose) treatment could partly restore the morphometric and biomechanical remodeling of colon in diabetic rats. One mechanism for CRT...

  11. [Biomechanics of the ankle joint].

    Science.gov (United States)

    Zwipp, H

    1989-03-01

    According to Fick, the tree-dimensional patterns of foot motion are best characterized as jawlike movement. Anatomically and biomechanically, this process represents conjoined, synchronous motion within the three mobile segments of the hindfoot: the ankle joint, the posterior subtalar joint, and the anterior subtalar joint. Foot kinematics can be described more completely if the anterior subtalar joint is defined not only as the talocalcaneal navicular joint, but as including the calcaneocuboid joint, thus representing the transverse joint of the tarsus, i.e., the Chopart joint. The axes of these three joints can be defined precisely. In some parts they represent a screwlike motion, clockwise or counter-clockwise, around the central ligamentous structures (fibulotibial ligament, talocalcaneal interosseous ligament, bifurcate ligament). The individual anatomy and structure of these ligaments provide variations in the degree and direction of foot motion. A precise knowledge of foot kinematics is important in surgical ligament and joint reconstruction and in selective foot arthrodeses.

  12. Biomechanics of Rowing

    Science.gov (United States)

    Hase, Kazunori; Kaya, Motoshi; Yamazaki, Nobutoshi; Andrews, Brian J.; Zavatsky, Amy B.; Halliday, Suzanne E.

    Compared with the other exercise, such as walking and cycling, rowing was expected to have some fitness advantage, while there were some misgivings about the risk of injury. The objectives of this study were to quantify biomechanical characteristics of rowing for fitness and rehabilitation and to offer normative data for the prevention of injury and for determining effective exercise. An experiment was performed to collect the kinematic and kinetic data during rowing by experienced and non-experienced subjects. A three-dimensional whole-body musculo-skeletal model was used to calculate the biomechanical loads, such as the joint moments, the muscular tensions, the joint contact forces and the energy consumption. The results of this study indicate that rowing is an effective exercise for rehabilitation and fitness. However, the non-experienced rower should acquire considerable skill to obtain sufficient exercise. The rowing cadence should be decided according to the purpose of the exercise.

  13. Risk management in clinical practice. Part 9. Dental implants.

    Science.gov (United States)

    Palmer, R M

    2010-11-27

    Patients have high expectations of dental implants in terms of appearance, function and longevity. It is essential that these expectations are realistically managed and that treatment of the highest standard is provided. This involves very careful evaluation, including clinical and radiographic, and presentation of the pros and cons of treatment alternatives. Provision of a successful implant restoration requires many skills including a surgical procedure to place the implant in the best possible position and prosthodontic techniques to provide an aesthetic restoration in occlusal harmony with the rest of the dentition. Recognition of risk factors and long-term maintenance requirements are equally important. Clinicians involved in these treatments must obtain adequate training and develop skills through treatment of straightforward cases using well established protocols before embarking on more demanding cases.

  14. [Polyetheretherketone (PEEK). Part II: application in clinical practice].

    Science.gov (United States)

    Pokorný, D; Fulín, P; Slouf, M; Jahoda, D; Landor, I; Sosna, A

    2010-01-01

    Polyetheretherketone (PEEK) is one of the up-to-date organic polymer thermoplastics with applications in orthopaedics and trauma medicine. This study presents a detailed analysis of its tests and applications in clinical medicine. A wide range of PEEK modifications and composites are commercially available, e.g., PEEK-Classix, PEEK-Optima, Endolign and Motis. They differ in their physical properties, which makes them suitable for different applications. Other forms, so-called PEEK bioactive composites, contain beta-tricalcium phosphate and hydroxyapatite. Research in this field is also concerned with the surface finish of this polymer thermoplastic and involves macroporous titanium and hydroxyapatite layers, or treatment with laser for an exactly defined surface structure. The clinical applications of PEEK and its composites include, in addition to components for spinal surgery, osteosynthesis plates, screws, intramedullary nails or external fixators, which are implants still at the stage of prototypes. In this review, attention is paid to the use of PEEK thermoplastics for joint replacement. Mid-term studies involving hundreds of patients have shown that, for instance, the VerSys Epoch Fullcoat Hip System (Zimmer) has a markedly lower stress-shielding effect. Carbon fibre-reinforced (CFR-PEEK) composites are used to make articulating components for total hip replacement. Their convenient properties allow for production of much thinner liners and an enlargement of the femoral head diameter, thus reducing the wear of joint implants. CFR-PEEK composites are particularly effective for hip resurfacing in which the Mitch PCR (Stryker) acetabular component has been used with good results. The MOTIS polymer acetabular cup (Invibio Ltd.) is another example. Further PEEK applications include the construction of finger-joint prostheses (Mathys AG), suture anchors (Stryker) and various kinds of augmentations (Medin). Based on the information obtained, the authors suggest

  15. 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.

  16. Gait biomechanics in the era of data science.

    Science.gov (United States)

    Ferber, Reed; Osis, Sean T; Hicks, Jennifer L; Delp, Scott L

    2016-12-08

    Data science has transformed fields such as computer vision and economics. The ability of modern data science methods to extract insights from large, complex, heterogeneous, and noisy datasets is beginning to provide a powerful complement to the traditional approaches of experimental motion capture and biomechanical modeling. The purpose of this article is to provide a perspective on how data science methods can be incorporated into our field to advance our understanding of gait biomechanics and improve treatment planning procedures. We provide examples of how data science approaches have been applied to biomechanical data. We then discuss the challenges that remain for effectively using data science approaches in clinical gait analysis and gait biomechanics research, including the need for new tools, better infrastructure and incentives for sharing data, and education across the disciplines of biomechanics and data science. By addressing these challenges, we can revolutionize treatment planning and biomechanics research by capitalizing on the wealth of knowledge gained by gait researchers over the past decades and the vast, but often siloed, data that are collected in clinical and research laboratories around the world.

  17. 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 ...

  18. Biomechanics as a window into the neural control of movement.

    Science.gov (United States)

    Latash, Mark L

    2016-09-01

    Biomechanics and motor control are discussed as parts of a more general science, physics of living systems. Major problems of biomechanics deal with exact definition of variables and their experimental measurement. In motor control, major problems are associated with formulating currently unknown laws of nature specific for movements by biological objects. Mechanics-based hypotheses in motor control, such as those originating from notions of a generalized motor program and internal models, are non-physical. The famous problem of motor redundancy is wrongly formulated; it has to be replaced by the principle of abundance, which does not pose computational problems for the central nervous system. Biomechanical methods play a central role in motor control studies. This is illustrated with studies with the reconstruction of hypothetical control variables and those exploring motor synergies within the framework of the uncontrolled manifold hypothesis. Biomechanics and motor control have to merge into physics of living systems, and the earlier this process starts the better.

  19. A Diagnostic Approach to Autoimmune Disorders: Clinical Manifestations: Part 1.

    Science.gov (United States)

    Sahai, Shashi; Adams, Matthew; Kamat, Deepak

    2016-06-01

    Autoimmune disorders are not commonly encountered in a general pediatric practice, but they may mimic many other disorders. Although they occur infrequently, it is always important to pause and consider an autoimmune disorder in the differential diagnosis. A detailed history and careful physical examination play an important role in guiding laboratory evaluation for these disorders. Many autoimmune disorders present with symptoms that involve multiple organ systems. The common symptoms that may make one consider a rheumatic disorder in the differential diagnosis are fever, fatigue, joint pain, rash, ulcers, and muscle weakness. The most common reason for referral to a pediatric rheumatologist is joint pain. A good joint examination may be performed by the use of the pediatric Gait, Arms, Legs, Spine screen, which is a validated screening tool. A small portion of children with fever of unknown origin may have an autoimmune disorder, with a majority of them having an infectious disease. Some patients with undiagnosed rheumatic disorders may present to the emergency. department. The characteristics of historic and clinical examination features of various autoimmune disorders are discussed in this article. [Pediatr Ann. 2016;45(6):e223-e229.].

  20. 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.

  1. Anatomical and biomechanical traits of broiler chickens across ontogeny. Part II. Body segment inertial properties and muscle architecture of the pelvic limb

    Directory of Open Access Journals (Sweden)

    Heather Paxton

    2014-07-01

    Full Text Available In broiler chickens, genetic success for desired production traits is often shadowed by welfare concerns related to musculoskeletal health. Whilst these concerns are clear, a viable solution is still elusive. Part of the solution lies in knowing how anatomical changes in afflicted body systems that occur across ontogeny influence standing and moving. Here, to demonstrate these changes we quantify the segment inertial properties of the whole body, trunk (legs removed and the right pelvic limb segments of five broilers at three different age groups across development. We also consider how muscle architecture (mass, fascicle length and other properties related to mechanics changes for selected muscles of the pelvic limb. All broilers used had no observed lameness, but we document the limb pathologies identified post mortem, since these two factors do not always correlate, as shown here. The most common leg disorders, including bacterial chondronecrosis with osteomyelitis and rotational and angular deformities of the lower limb, were observed in chickens at all developmental stages. Whole limb morphology is not uniform relative to body size, with broilers obtaining large thighs and feet between four and six weeks of age. This implies that the energetic cost of swinging the limbs is markedly increased across this growth period, perhaps contributing to reduced activity levels. Hindlimb bone length does not change during this period, which may be advantageous for increased stability despite the increased energetic costs. Increased pectoral muscle growth appears to move the centre of mass cranio-dorsally in the last two weeks of growth. This has direct consequences for locomotion (potentially greater limb muscle stresses during standing and moving. Our study is the first to measure these changes in the musculoskeletal system across growth in chickens, and reveals how artificially selected changes of the morphology of the pectoral apparatus may cause

  2. Biomechanical issues in endovascular device design.

    Science.gov (United States)

    Moore, James E

    2009-02-01

    The biomechanical nature of the arterial system and its major disease states provides a series of challenges to treatment strategies. Endovascular device design objectives have mostly centered on short-term challenges, such as deployability and immediate restoration of reliable flow channels. The resulting design features may be at odds with long-term clinical success. In-stent restenosis, endoleaks, and loss of device structural integrity (e.g., strut fractures) are all manifestations of a lack of compatibility between the host vessel biomechanical environment and the implant design. Initial attempts to adapt device designs for increased compatibility, including drug-eluting and bioabsorbable stents, barely begin to explore the ways in which implant design can be modulated in time to minimize risk of failure. Biomechanical modeling has the potential to provide a virtual vascular environment in which new designs can be tested for their implications on long-term tissue reaction. These models will be based on high quality, highly resolved imaging information, as well as mechanobiology experiments from the cellular to the whole tissue level. These models can then be extended to incorporate biodegradation mechanics, facilitating the next generations of devices whose designs (including drug delivery profiles) change with time to enhance healing. The possibility of initiating changes in device design or drug release according to information on vascular healing (through clinical intervention or automated methods) provides the opportunity for truly individualized dynamic device design optimization.

  3. Cervical spondylosis anatomy: pathophysiology and biomechanics.

    Science.gov (United States)

    Shedid, Daniel; Benzel, Edward C

    2007-01-01

    Cervical spondylosis is the most common progressive disorder in the aging cervical spine. It results from the process of degeneration of the intervertebral discs and facet joints of the cervical spine. Biomechanically, the disc and the facets are the connecting structures between the vertebrae for the transmission of external forces. They also facilitate cervical spine mobility. Symptoms related to myelopathy and radiculopathy are caused by the formation of osteophytes, which compromise the diameter of the spinal canal. This compromise may also be partially developmental. The developmental process, together with the degenerative process, may cause mechanical pressure on the spinal cord at one or multiple levels. This pressure may produce direct neurological damage or ischemic changes and, thus, lead to spinal cord disturbances. A thorough understanding of the biomechanics, the pathology, the clinical presentation, the radiological evaluation, as well as the surgical indications of cervical spondylosis, is essential for the management of patients with cervical spondylosis.

  4. Parameters that effect spine biomechanics following cervical disc replacement.

    Science.gov (United States)

    Goel, Vijay K; Faizan, Ahmad; Palepu, Vivek; Bhattacharya, Sanghita

    2012-06-01

    Total disc replacement (TDR) is expected to provide a more physiologic alternative to fusion. However, long-term clinical data proving the efficacy of the implants is lacking. Limited clinical data suggest somewhat of a disagreement between the in vitro biomechanical studies and in vivo assessments. This conceptual paper presents the potential biomechanical challenges affecting the TDR that should be addressed with a hope to improve the clinical outcomes and our understanding of the devices. Appropriate literature and our own research findings comparing the biomechanics of different disc designs are presented to highlight the need for additional investigations. The biomechanical effects of various surgical procedures are analyzed, reiterating the importance of parameters like preserving uncinate processes, disc placement and its orientation within the cervical spine. Moreover, the need for a 360° dynamic system for disc recipients who may experience whiplash injuries is explored. Probabilistic studies as performed already in the lumbar spine may explore high risk combinations of different parameters and explain the differences between "standard" biomechanical investigations and clinical studies. Development of a patient specific optimized finite element model that takes muscle forces into consideration may help resolve the discrepancies between biomechanics of TDR and the clinical studies. Factors affecting long-term performance such as bone remodeling, subsidence, and wear are elaborated. In vivo assessment of segmental spine motion has been, and continues to be, a challenge. In general, clinical studies while reporting the data have placed lesser emphasis on kinematics following intervertebral disc replacements. Evaluation of in vivo kinematics following TDR to analyze the quality and quantity of motion using stereoradiogrammetric technique may be needed.

  5. Hyposplenism: a comprehensive review. Part II: clinical manifestations, diagnosis, and management.

    Science.gov (United States)

    William, Basem M; Thawani, Nitika; Sae-Tia, Sutthichai; Corazza, Gino R

    2007-04-01

    In the first part of this review, we described the physiological basis of splenic function and hypofunction. We also described the wide spectrum of diseases that can result in functional hyposplenism. In the second part of this review, we will be discussing the clinical picture, including complications, diagnostic methods, and management of hyposplenism.

  6. Minicomputer For Biomechanical Research

    Science.gov (United States)

    Shierman, Gail; Rhymes, Tom

    1982-02-01

    The increased capabilities of minicomputers today allows a biomechanics laboratory to establish a self-contained computer system for a reasonable price. The system includes a microprocessor, a printer and a CRT. Analog to digital conversion is an important feature to consider as well as the ability to interface with a mainframe computer. A minicomputer adapted for film analysis should be a consideration for data analysis when developing a cinematography laboratory. For the past 10-15 years the area of biomechanics has enjoyed the advances in technology. Equipment and instrumentation once used exclusively by engineers and physicists have become readily available to those involved with snorts analyses. Among the various pieces of equipment accessible to biomechanists today, probably the most important one is the computer. At this time several biomechanics laboratories are using the computer to analyze kinematic and kinetic data obtained from film. The computer in use at each school is generally the main University or College computer with a remote terminal set-up in the biomechanics laboratory. This system functions well if there is adequate response from the time-sharing system of the main computer, and if there is at least one knowledgeable technician available. With the trend toward minicomputers today, their increased capabilities, and their ease of use, a self-contained minicomputer system in the biomechanics laboratory appears to be a viable alternative. The computer system in use in the ,Biomechanics Laboratory at the University of Oklahoma is based around the Cromemco Z2D computer connected to a PCD motion analyzer (Figure 1). The data acquisition system consists of the eight-bit microprocessor-based minicomputer connected to an analog to digital converter (ADC). As a terminal for the computer, we have either a video display unit or a Model 43 Teletype. The Model 43 provides a hard copy out-put while the video terminal provides much faster I/O, useful for

  7. CURRENT CONCEPTS IN BIOMECHANICAL INTERVENTIONS FOR PATELLOFEMORAL PAIN

    Science.gov (United States)

    Meira, Erik P.

    2016-01-01

    Patellofemoral pain (PFP) has historically been a complex and enigmatic issue. Many of the factors thought to relate to PFP remain after patients' symptoms have resolved making their clinical importance difficult to determine. The tissue homeostasis model proposed by Dye in 2005 can assist with understanding and implementing biomechanical interventions for PFP. Under this model, the goal of interventions for PFP should be to re-establish patellofemoral joint (PFJ) homeostasis through a temporary alteration of load to the offended tissue, followed by incrementally restoring the envelope of function to the baseline level or higher. High levels of PFJ loads, particularly in the presence of an altered PFJ environment, are thought to be a factor in the development of PFP. Clinical interventions often aim to alter the biomechanical patterns that are thought to result in elevated PFJ loads while concurrently increasing the load tolerance capabilities of the tissue through therapeutic exercise. Biomechanics may play a role in PFJ load modification not only when addressing proximal and distal components, but also when considering the involvement of more local factors such as the quadriceps musculature. Biomechanical considerations should consider the entire kinetic chain including the hip and the foot/ankle complex, however the beneficial effects of these interventions may not be the result of long-term biomechanical changes. Biomechanical alterations may be achieved through movement retraining, but the interventions likely need to be task-specific to alter movement patterns. The purpose of this commentary is to describe biomechanical interventions for the athlete with PFP to encourage a safe and complete return to sport. Level of Evidence 5 PMID:27904791

  8. 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.

  9. 颈椎复合骨块融合的生物力学基础与疗效观察%Biomechanical basis and clinical aplication of combined bone graft in anterior cervical fusion

    Institute of Scientific and Technical Information of China (English)

    王春; 郭卫中; 刘成招; 郑立槟; 王以进

    2001-01-01

    目的 探讨颈椎前路复合骨植骨块融合的生物力学基础,为临床手术提供理论依据。方法 利用6具颈椎新鲜标本,采用复合骨块与常规髂骨块制成颈前路减压植骨融合标本,以实验应力分析手段观察和评定颈椎的三维稳定性及术后颈椎强度等生物力学指标的变化。并对临床运用复合骨块行颈椎植骨融合21例进行回故并与常规植骨融合病例对照。结果 复合骨块融合组的生物力学性能均优于常规髂骨融合组。(P<0.01)结论 颈椎前路复合骨块融合方便、稳定。是目前较好的植骨融合方法之一。%Objective To understand the biomechanical basis and evaluate clinical application of combined bone graft in anterior cervical fusion.Methods The cervical speciments of 6 cadavers prepared from decompressing and transplanting fusion anterior with combined iliac bone graft.It was evaluated that the cervical stability and intensity by stress determination.21 patients with combined bone graft in anterior cervical fusion were analyzed.The comparision of the cervical aligment and hight on disc space between the combine bone graft and the biomechanical standard.Result The patient with combine bone graft was significantly greater at cervical height of disc space and stability than routine iliac bone graft.Conclusion The combine bone graft is better method in anterior cervical fusion.

  10. 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…

  11. Time-Dependent Lagrangian Biomechanics

    CERN Document Server

    Ivancevic, Tijana T

    2009-01-01

    In this paper we present the time-dependent generalization of an 'ordinary' autonomous human musculo-skeletal biomechanics. We start with the configuration manifold of human body, given as a set of its all active degrees of freedom (DOF). 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. On this extended configuration space we develop time-dependent biomechanical Lagrangian dynamics, using derived jet spaces of velocities and accelerations, as well as the underlying geometric evolution of the mass-inertia matrix. Keywords: Human time-dependent biomechanics, configuration manifold, jet spaces, geometric evolution

  12. 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...

  13. Inside the 2016 American Society of Clinical Oncology Genitourinary Cancers Symposium: part 1 - kidney cancer.

    Science.gov (United States)

    Buti, Sebastiano; Ciccarese, Chiara; Iacovelli, Roberto; Bersanelli, Melissa; Scarpelli, Marina; Lopez-Beltran, Antonio; Cheng, Liang; Montironi, Rodolfo; Tortora, Giampaolo; Massari, Francesco

    2016-09-01

    The American Society of Clinical Oncology Genitourinary Cancers Symposium, Moscone West Building, San Francisco, CA, USA, 7-9 January 2016 The American Society of Clinical Oncology (ASCO) Genitourinary Cancers Symposium, held in San Francisco (CA, USA), from 7 to 9 January 2016, focused on 'patient-centric care: translating research to results'. Every year, this meeting is a must for anyone studying genitourinary tumors to keep abreast of the most recent innovations in this field, exchange views on behaviors customarily adopted in daily clinical practice, and discuss future topics of scientific research. This two-part report highlights the key themes presented at the 2016 ASCO Genitourinary Cancers Symposium, with part 1 reporting the main novelties of kidney cancer and part 2 discussing the most relevant issues which have emerged for bladder and prostate tumors.

  14. Developmental biomechanics of the cervical spine: Tension and compression.

    Science.gov (United States)

    Nuckley, David J; Ching, Randal P

    2006-01-01

    Epidemiological data and clinical indicia reveal devastating consequences associated with pediatric neck injuries. Unfortunately, neither injury prevention nor clinical management strategies will be able to effectively reduce these injuries or their effects on children, without an understanding of the cervical spine developmental biomechanics. Thus, we investigated the relationship between spinal development and the functional (stiffness) and failure biomechanical characteristics of the cervical spine in a baboon model. A correlation study design was used to define the relationships between spinal tissue maturation and spinal biomechanics in both tension and compression. Eighteen baboon cervical spine specimens distributed across the developmental spectrum (1-26 human equivalent years) were dissected into osteoligamentous functional spinal units. Using a servo-hydraulic MTS, these specimens (Oc-C2, C3-C4, C5-C6, C7-T1) were non-destructively tested in tension and compression and then displaced to failure in tension while measuring the six-axes of loads and displacements. The functions describing the developmental biomechanical response of the cervical spine for stiffness and normalized stiffness exhibited a significant direct relationship in both tension and compression loading. Similarly, the tensile failure load and normalized failure load demonstrated significant maturational increases. Further, differences in biomechanical response were observed between the spinal levels examined and all levels exhibited clinically relevant failure patterns. These data support our understanding of the child cervical spine from a developmental biomechanics perspective and facilitate the development of injury prevention or management schema for the mitigation of child spine injuries and their deleterious effects.

  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. The biomechanics of soccer: a review.

    Science.gov (United States)

    Lees, A; Nolan, L

    1998-04-01

    This review considers the biomechanical factors that are relevant to success in the game of soccer. Three broad areas are covered: (1) the technical performance of soccer skills; (2) the equipment used in playing the game; and (3) the causative mechanisms of specific soccer injuries. Kicking is the most widely studied soccer skill. Although there are many types of kick, the variant most widely reported in the literature is the maximum velocity instep kick of a stationary ball. In contrast, several other skills, such as throwing-in and goalkeeping, have received little attention; some, for example passing and trapping the ball, tackling, falling behaviour, jumping, running, sprinting, starting, stopping and changing direction, have not been the subject of any detailed biomechanical investigation. The items of equipment reviewed are boots, the ball, artificial and natural turf surfaces and shin guards. Little of the research conducted by equipment manufacturers is in the public domain; this part of the review therefore concentrates on the mechanical responses of equipment, player-equipment interaction, and the effects of equipment on player performance and protection. Although the equipment has mechanical characteristics that can be reasonably well quantified, the player-equipment interaction is more difficult to establish; this makes its efficacy for performance or protection difficult to predict. Some soccer injuries may be attributable to the equipment used. The soccer boot has a poor protective capability, but careful design can have a minor influence on reducing the severity of ankle inversion injuries. Performance requirements limit the scope for reducing these injuries; alternative methods for providing ankle stability are necessary. Artificial surfaces result in injury profiles different from those on natural turf pitches. There is a tendency for fewer serious injuries, but more minor injuries, on artificial turf than on natural turf pitches. Players adapt to

  17. Biomechanics of sport concussion: quest for the elusive injury threshold.

    Science.gov (United States)

    Guskiewicz, Kevin M; Mihalik, Jason P

    2011-01-01

    Previous concussion biomechanics research has relied heavily on the animal model or laboratory reconstruction of concussive injuries captured on video footage. Real-time data collection involves a novel approach to better understanding the medical issues related to sport concussion. Recent studies suggest that a concussive injury threshold is elusive and may, in fact, be irrelevant when predicting the clinical outcome.

  18. Biomechanics of metastatic disease in the vertebral column.

    Science.gov (United States)

    Whyne, Cari M

    2014-06-01

    Metastatic disease in the vertebral column compromises the structural stability of the spine leading to increased risk of fracture. The complex patterns of osteolytic and osteoblastic disease within the bony spine have motivated a multimodal approach to better characterize the biomechanics of tumor-involved bone. This review presents our current understanding of the biomechanical behavior of metastatically involved vertebrae, and experimental and computational image-based approaches that have been employed to quantify structural integrity in preclinical models with translation to clinical data sets.

  19. Biomechanics of whiplash injury

    Institute of Scientific and Technical Information of China (English)

    CHEN Hai-bin; King H YANG; WANG Zheng-guo

    2009-01-01

    Despite a large number of rear-end collisions on the road and a high frequency of whiplash injuries reported, the mechanism of whiplash injuries is not completely understood. One of the reasons is that the injury is not necessarily accompanied by obvious tissue damage detectable by X-ray or MRI. An extensive series of biomechanics studies, including injury epidemiology, neck kinematics,facet capsule ligament mechanics, injury mechanisms and injury criteria, were undertaken to help elucidate these whiplash injury mechanisms and gain a better understanding of cervical facet pain. These studies provide the following evidences to help explain the mechanisms of the whiplash injury: (1) Whiplash injuries are generally considered to be a soft tissue injury of the neck with symptoms such as neck pain and stiffness, shoulder weakness, dizziness, headache and memory loss, etc. (2) Based on kinematical studies on the cadaver and volunteers, there are three distinct periods that have the potential to cause injury to the neck. In the first stage, flexural deformation of the neck is observed along with a loss of cervical lordosis; in the second stage, the cervical spine assumes an S-shaped curve as the lower vertebrae begin to extend and gradually cause the upper vertebrae to extend; during the final stage, the entire neck is extended due to the extension moments at both ends. (3)The in vivo environment afforded by rodent models of injury offers particular utility for linking mechanics, nociception and behavioral outcomes. Experimental findings have examined strains across the facet joint as a mechanism of whiplash injury, and suggested a capsular strain threshold or a vertebral distraction threshold for whiplash-related injury,potentially producing neck pain. (4) Injuries to the facet capsule region of the neck are a major source of post-crash pain. There are several hypotheses on how whiplash-associated injury may occur and three of these injuries are related to strains within

  20. Biomechanics of whiplash injury.

    Science.gov (United States)

    Chen, Hai-bin; Yang, King H; Wang, Zheng-guo

    2009-10-01

    Despite a large number of rear-end collisions on the road and a high frequency of whiplash injuries reported, the mechanism of whiplash injuries is not completely understood. One of the reasons is that the injury is not necessarily accompanied by obvious tissue damage detectable by X-ray or MRI. An extensive series of biomechanics studies, including injury epidemiology, neck kinematics, facet capsule ligament mechanics, injury mechanisms and injury criteria, were undertaken to help elucidate these whiplash injury mechanisms and gain a better understanding of cervical facet pain. These studies provide the following evidences to help explain the mechanisms of the whiplash injury: (1) Whiplash injuries are generally considered to be a soft tissue injury of the neck with symptoms such as neck pain and stiffness, shoulder weakness, dizziness, headache and memory loss, etc. (2) Based on kinematical studies on the cadaver and volunteers, there are three distinct periods that have the potential to cause injury to the neck. In the first stage, flexural deformation of the neck is observed along with a loss of cervical lordosis; in the second stage, the cervical spine assumes an S-shaped curve as the lower vertebrae begin to extend and gradually cause the upper vertebrae to extend; during the final stage, the entire neck is extended due to the extension moments at both ends. (3) The in vivo environment afforded by rodent models of injury offers particular utility for linking mechanics, nociception and behavioral outcomes. Experimental findings have examined strains across the facet joint as a mechanism of whiplash injury, and suggested a capsular strain threshold or a vertebral distraction threshold for whiplash-related injury, potentially producing neck pain. (4) Injuries to the facet capsule region of the neck are a major source of post-crash pain. There are several hypotheses on how whiplash-associated injury may occur and three of these injuries are related to strains

  1. Aging and facial changes--documenting clinical signs, part 1: clinical changes of the aging face.

    Science.gov (United States)

    Nkengne, Alex; Bertin, Christiane

    2012-01-01

    The process of aging induces the transformation of the face with changes that are usually classified as either chronological or photo induced and that affect the shape, the texture, and the color of the face. Facial shape is mainly transformed by the evolution of bones and soft tissues (muscles, fat, and skin) in addition to noticeable effects of gravity. Skin texture is mainly determined by wrinkles, which arise from atrophy of the skin layers, elastosis, and facial expressions. Skin color is related to the distribution of skin chromophores and the structure of the dermis, which affects light scattering. All facial changes are dependant on sex, ethnicity, and lifestyle. They affect self-perception and social interactions and can sometimes be slowed down or reversed using appropriate clinical procedures (e.g., dermatological, surgical, and cosmetic interventions).

  2. Benefits of Repetitive Transcranial Magnetic Stimulation (rTMS for Spastic Subjects: Clinical, Functional, and Biomechanical Parameters for Lower Limb and Walking in Five Hemiparetic Patients

    Directory of Open Access Journals (Sweden)

    Luc Terreaux

    2014-01-01

    Full Text Available Introduction. Spasticity is a disabling symptom resulting from reorganization of spinal reflexes no longer inhibited by supraspinal control. Several studies have demonstrated interest in repetitive transcranial magnetic stimulation in spastic patients. We conducted a prospective, randomized, double-blind crossover study on five spastic hemiparetic patients to determine whether this type of stimulation of the premotor cortex can provide a clinical benefit. Material and Methods. Two stimulation frequencies (1 Hz and 10 Hz were tested versus placebo. Patients were assessed clinically, by quantitative analysis of walking and measurement of neuromechanical parameters (H and T reflexes, musculoarticular stiffness of the ankle. Results. No change was observed after placebo and 10 Hz protocols. Clinical parameters were not significantly modified after 1 Hz stimulation, apart from a tendency towards improved recruitment of antagonist muscles on the Fügl-Meyer scale. Only cadence and recurvatum were significantly modified on quantitative analysis of walking. Neuromechanical parameters were modified with significant decreases in Hmax⁡ /Mmax⁡ and T/Mmax⁡ ratios and stiffness indices 9 days or 31 days after initiation of TMS. Conclusion. This preliminary study supports the efficacy of low-frequency TMS to reduce reflex excitability and stiffness of ankle plantar flexors, while clinical signs of spasticity were not significantly modified.

  3. Benefits of Repetitive Transcranial Magnetic Stimulation (rTMS) for Spastic Subjects: Clinical, Functional, and Biomechanical Parameters for Lower Limb and Walking in Five Hemiparetic Patients

    Science.gov (United States)

    Gross, Raphael; Leboeuf, Fabien; Desal, Hubert; Hamel, Olivier; Nguyen, Jean Paul; Pérot, Chantal; Buffenoir, Kévin

    2014-01-01

    Introduction. Spasticity is a disabling symptom resulting from reorganization of spinal reflexes no longer inhibited by supraspinal control. Several studies have demonstrated interest in repetitive transcranial magnetic stimulation in spastic patients. We conducted a prospective, randomized, double-blind crossover study on five spastic hemiparetic patients to determine whether this type of stimulation of the premotor cortex can provide a clinical benefit. Material and Methods. Two stimulation frequencies (1 Hz and 10 Hz) were tested versus placebo. Patients were assessed clinically, by quantitative analysis of walking and measurement of neuromechanical parameters (H and T reflexes, musculoarticular stiffness of the ankle). Results. No change was observed after placebo and 10 Hz protocols. Clinical parameters were not significantly modified after 1 Hz stimulation, apart from a tendency towards improved recruitment of antagonist muscles on the Fügl-Meyer scale. Only cadence and recurvatum were significantly modified on quantitative analysis of walking. Neuromechanical parameters were modified with significant decreases in Hmax⁡ /Mmax⁡ and T/Mmax⁡ ratios and stiffness indices 9 days or 31 days after initiation of TMS. Conclusion. This preliminary study supports the efficacy of low-frequency TMS to reduce reflex excitability and stiffness of ankle plantar flexors, while clinical signs of spasticity were not significantly modified. PMID:24883390

  4. Applied Biomechanics Research for the United States Ski Team.

    Science.gov (United States)

    Dillman, Charles J.

    1982-01-01

    Assisted by a team of physicians and sports scientists, the United States Ski Team has developed its own sports medicine program, the purpose of which is to assist coaches and athletes in controlling and optimizing factors which influence skiing performance. A number of biomechanical research projects which have been undertaken as part of this…

  5. Biomechanics and functionality of hepatocytes in liver cirrhosis.

    Science.gov (United States)

    Sun, Shan; Song, Zhenyuan; Cotler, Scott J; Cho, Michael

    2014-06-27

    Cirrhosis is a life-threatening condition that is generally attributed to overproduction of collagen fibers in the extracellular matrix that mechanically stiffens the liver. Chronic liver injury due to causes including viral hepatitis, inherited and metabolic liver diseases and external factors such as alcohol abuse can result in the development of cirrhosis. Progression of cirrhosis leads to hepatocellular dysfunction. While extensive studies to understand the complexity underlying liver fibrosis have led to potential application of anti-fibrotic drugs, no such FDA-approved drugs are currently available. Additional studies of hepatic fibrogenesis and cirrhosis primarily have focused on the extracellular matrix, while hepatocyte biomechanics has received limited attention. The role of hepatocyte biomechanics in liver cirrhosis remains elusive, and how the cell stiffness is correlated with biological functions of hepatocytes is also unknown. In this study, we demonstrate that the biomechanical properties of hepatocytes are correlated with their functions (e.g., glucose metabolism), and that hepatic dysfunction can be restored through modulation of the cellular biomechanics. Furthermore, our results indicate the hepatocyte functionality appears to be regulated through a crosstalk between the Rho and Akt signaling. These novel findings may lead to biomechanical intervention of hepatocytes and the development of innovative tissue engineering for clinical treatment to target liver cells rather than exclusively focusing on the extracellular matrix alone in liver cirrhosis.

  6. 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.

  7. 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...

  8. 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.

  9. Pilot assessment of patient satisfaction and clinical impact of Medicare Part D in diabetic geriatric patients

    Directory of Open Access Journals (Sweden)

    Kim SL

    2008-09-01

    Full Text Available Objectives: To assess patients’ 1 satisfaction with their decision to enroll or not enroll in the Medicare Part D program, and 2 clinical status of diabetes before and after decision to enroll in Medicare Part D.Methods: Patients 65 years or older were enrolled in the study from November 2006 through February 2007. Patients were screened by a clinical pharmacist at their clinician visit and administered a Medicare Part D satisfaction survey. Upon completion of the survey, a retrospective chart review was completed in diabetic patients who were enrolled in Medicare Part D to assess goal attainment of glycosylated hemoglobin (HbA1c, low-density lipoprotein (LDL and blood pressure. Pre-enrollment values were obtained in the 6 months prior to the start of Medicare Part D enrollment (July 1- December 31, 2005. Post-enrollment values were obtained after enrollment was complete for the 2006 year (May 1- October 31, 2006.Results: Results show that 74% (60/81 of patients surveyed were enrolled into the Medicare Part D program, including patients who have dual eligibility. Of the 60 patients who were enrolled in Medicare Part D, 48 patients (80.0% responded that they were satisfied with their decision to enroll. Clinical outcomes were unchanged from the pre-enrollment to the post-enrollment periods. Mean HbA1c was 7.47% in the pre-enrollment period and 7.25% post-enrollment (differencepre-post = 0.23; 95%CI = -0.28 to 0.73. There was no change in LDL in the two time periods (pre = 79.4 mg/dL; post = 79.7; differencepre-post = -0.25; 95%CI = -13.6 to 13.1. Similarly, there were no significant differences observed for blood pressure. Mean systolic blood pressure was 129.5 in the pre-enrollment period and 131.6 in the post-enrollment period (differencepre-post = -2.1; 95%CI = -7.0 to 2.7. Mean diastolic blood pressure was 70.3 for the pre-enrollment period and 70.7 for the post-enrollment period (differencepre-post = -0.4; 95%CI = -4.2 to 3.4.Conclusion

  10. The biomechanics of seed germination.

    Science.gov (United States)

    Steinbrecher, Tina; Leubner-Metzger, Gerhard

    2016-12-07

    From a biomechanical perspective, the completion of seed (and fruit) germination depends on the balance of two opposing forces: the growth potential of the embryonic axis (radicle-hypocotyl growth zone) and the restraint of the seed-covering layers (endosperm, testa, and pericarp). The diverse seed tissues are composite materials which differ in their dynamic properties based on their distinct cell wall composition and water uptake capacities. The biomechanics of embryo cell growth during seed germination depend on irreversible cell wall loosening followed by water uptake due to the decreasing turgor, and this leads to embryo elongation and eventually radicle emergence. Endosperm weakening as a prerequisite for radicle emergence is a widespread phenomenon among angiosperms. Research into the biochemistry and biomechanics of endosperm weakening has demonstrated that the reduction in puncture force of a seed's micropylar endosperm is environmentally and hormonally regulated and involves tissue-specific expression of cell wall remodelling proteins such as expansins, diverse hydrolases, and the production of directly acting apoplastic reactive oxygen. The endosperm-weakening biomechanics and its underlying cell wall biochemistry differ between the micropylar (ME) and chalazal (CE) endosperm domains. In the ME, they involve cell wall loosening, cell separation, and programmed cell death to provide decreased and localized ME tissue resistance, autolysis, and finally the formation of an ME hole required for radicle emergence. Future work will further unravel the molecular mechanisms, environmental regulation, and evolution of the diverse biomechanical cell wall changes underpinning the control of germination by endosperm weakening.

  11. 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)

  12. 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.

  13. [Quality assurance and quality improvement in medical practice. Part 3: Clinical audit in medical practice].

    Science.gov (United States)

    Godény, Sándor

    2012-02-01

    The first two articles in the series were about the definition of quality in healthcare, the quality approach, the importance of quality assurance, the advantages of quality management systems and the basic concepts and necessity of evidence based medicine. In the third article the importance and basic steps of clinical audit are summarised. Clinical audit is an integral part of quality assurance and quality improvement in healthcare, that is the responsibility of any practitioner involved in medical practice. Clinical audit principally measures the clinical practice against clinical guidelines, protocols and other professional standards, and sometimes induces changes to ensure that all patients receive care according to principles of the best practice. The clinical audit can be defined also as a quality improvement process that seeks to identify areas for service improvement, develop and carry out plans and actions to improve medical activity and then by re-audit to ensure that these changes have an effect. Therefore, its aims are both to stimulate quality improvement interventions and to assess their impact in order to develop clinical effectiveness. At the end of the article key points of quality assurance and improvement in medical practice are summarised.

  14. 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....

  15. 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.

  16. Biomechanical changes and clinical characteristics of cervical pedicle screws internal fixation%颈椎椎弓根螺钉置入内固定的生物力学变化及其临床特性

    Institute of Scientific and Technical Information of China (English)

    王华刚; 杨飞

    2011-01-01

    背景:颈椎椎弓根钉由于其独特的三维稳定性,越来越多的学者对其进行更加广泛的研究.目的:综述颈椎椎弓根解剖特点及椎弓根螺钉置钉的安全性和临床应用.方法:应用计算机检索1994-01/2010-09 CNKI及PubMed数据库相关文章,中文检索词为"颈椎弓根螺钉",英文检索词为"cervical pedicle screws",共检索到文献292篇,最终纳入符合标准的文献43篇.结果与结论:通过文献检索获得目前一致的观点认为颈椎弓根内固定由于是三维固定,因此可以获得良好的生物力学.但是,由于颈椎弓根周围毗邻部特殊的解剖结构,潜在血管、神经根和颈髓损伤的危险性,置入内固定风险及难度大,所以临床应用要做到个体化置钉.%BACKGROUND: More and more scholars have focused on cervical pedicle screws because of their unique three-dimensional stability.OBJECTIVE: To review the anatomic characteristics of the cervical pedicle, and to investigate the safety and clinical application of cervical pedicle screws.METHODS: The literature concerning the cervical pedicle screw internal fixation in recent years were extensively searched from CNKl and PubMed databases (1994-01/2010-09) using the keywords of "cervical pedicle screws" in Chinese and English. Forty-three articles of 292 were included in the result analysis.RESULTS AND CONCLUSION: Cervical pedicle screw fixation can obtain a good biomechanics based on its three-dimensional fixation. However, due to the special anatomic structures of the cervical pedicle adjacent to the surrounding, potential risks of blood vessel, nerve root and cervical spinal cord injuries, it is difficult to the internal fixation of cervical pedicle screws with a certain risk. The clinical application of pedicle screws should be individualized.

  17. Adapting social neuroscience measures for schizophrenia clinical trials, Part 1: ferrying paradigms across perilous waters.

    Science.gov (United States)

    Green, Michael F; Lee, Junghee; Ochsner, Kevin N

    2013-11-01

    Social cognitive impairment is prominent in schizophrenia, and it is closely related to functional outcome. Partly for these reasons, it has rapidly become a target for both training and psychopharmacological interventions. However, there is a paucity of reliable and valid social cognitive endpoints that can be used to evaluate treatment response in clinical trials. Also, clinical studies in schizophrenia have benefited rather little from the surge of activity and knowledge in nonclinical social neuroscience. The National Institute of Mental Health-sponsored study, "Social Cognition and Functioning in Schizophrenia" (SCAF), attempted to address this translational challenge by selecting paradigms from social neuroscience that could be adapted for use in schizophrenia. The project also evaluated the psychometric properties and external validity of the tasks to determine their suitability for multisite clinical trials. This first article in the theme section presents the goals, conceptual background, and rationale for the SCAF project.

  18. Angiotensin-converting enzyme inhibition in myocardial infarction--Part 1: Clinical data.

    Science.gov (United States)

    Huckell, V F; Bernstein, V; Cairns, J A; Crowell, R; Dagenais, G R; Higginson, L A; Isserow, S; Laramée, P; Liu, P; McCans, J L; Orchard, R C; Prewitt, R; Quinn, B P; Samson, M; Turazza, F; Warnica, J W; Wielgosz, A

    1997-02-01

    There is an increasing body of clinical trial evidence to support the use of angiotensin-converting enzyme (ACE) inhibitors in the management of patients following myocardial infarction (MI). Enthusiasm for the use of ACE inhibitors in the acute phase of MI had previously been tempered by the adverse results of an early trial. However, exciting new information is available from several large, randomized studies that has not only quelled those initial concerns but also attests to the efficacy of using this class of medication in the first 24 h after an acute MI. A Canadian National Opinion Leader Symposium was held in November 1995 to review the results of the major ACE inhibitor clinical trials and to discuss key issues and controversies surrounding their use in acute MI. The focus of this paper, the first of two parts, is on the results of the major ACE inhibitor clinical trials.

  19. 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.

  20. Inelastic mechanics: A unifying principle in biomechanics.

    Science.gov (United States)

    Gralka, Matti; Kroy, Klaus

    2015-11-01

    Many soft materials are classified as viscoelastic. They behave mechanically neither quite fluid-like nor quite solid-like - rather a bit of both. Biomaterials are often said to fall into this class. Here, we argue that this misses a crucial aspect, and that biomechanics is essentially damage mechanics, at heart. When deforming an animal cell or tissue, one can hardly avoid inducing the unfolding of protein domains, the unbinding of cytoskeletal crosslinkers, the breaking of weak sacrificial bonds, and the disruption of transient adhesions. We classify these activated structural changes as inelastic. They are often to a large degree reversible and are therefore not plastic in the proper sense, but they dissipate substantial amounts of elastic energy by structural damping. We review recent experiments involving biological materials on all scales, from single biopolymers over cells to model tissues, to illustrate the unifying power of this paradigm. A deliberately minimalistic yet phenomenologically very rich mathematical modeling framework for inelastic biomechanics is proposed. It transcends the conventional viscoelastic paradigm and suggests itself as a promising candidate for a unified description and interpretation of a wide range of experimental data. This article is part of a Special Issue entitled: Mechanobiology.

  1. [Evidence-based clinical practice. Part II--Searching evidence databases].

    Science.gov (United States)

    Bernardo, Wanderley Marques; Nobre, Moacyr Roberto Cuce; Jatene, Fábio Biscegli

    2004-01-01

    The inadequacy of most of traditional sources for medical information, like textbook and review article, do not sustained the clinical decision based on the best evidence current available, exposing the patient to a unnecessary risk. Although not integrated around clinical problem areas in the convenient way of textbooks, current best evidence from specific studies of clinical problems can be found in an increasing number of Internet and electronic databases. The sources that have already undergone rigorous critical appraisal are classified as secondary information sources, others that provide access to original article or abstract, as primary information source, where the quality assessment of the article rely on the clinician oneself . The most useful primary information source are SciELO, the online collection of Brazilian scientific journals, and Medline, the most comprehensive database of the USA National Library of Medicine, where the search may start with use of keywords, that were obtained at the structured answer construction (P.I.C.O.), with the addition of boolean operators "AND", "OR", "NOT". Between the secondary information sources, some of them provide critically appraised articles, like ACP Journal Club, Evidence Based Medicine and InfoPOEMs, others provide evidences organized as online texts, such as "Clinical Evidence" and "UpToDate", and finally, Cochrane Library are composed by systematic reviews of randomized controlled trials. To get studies that could answer the clinical question is part of a mindful practice, that is, becoming quicker and quicker and dynamic with the use of PDAs, Palmtops and Notebooks.

  2. 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

  3. Load-Speed Interaction Effects on the Biomechanics of Backpack Load Carriage

    Science.gov (United States)

    2001-05-01

    Backpack Load Carriage DISTRIBUTION: Approved for public release, distribution unlimited This paper is part of the following report: TITLE: Soldier...1 Load-Speed Interaction Effects on the Biomechanics of Backpack Load Carriage Everett Harman, Ki-Hoon Han, and Peter Frykman U.S. Army Research...Institute of Environmental Medicine Natick, MA, 01760-5007, U.S.A. Summary We biomechanically examined how backpack load and walking speed interact in

  4. An Update on Crown Lengthening. Part 2: Increasing Clinical Crown Height to Facilitate Predictable Restorations.

    Science.gov (United States)

    Kalsi, Harpoonam Jeet; Bomfim, Deborah Iola; Darbar, Ulpee

    2015-04-01

    This is the second paper in this two-part series. Paper one provided an overview of managing gingival tissue excess and paper two will focus on increasing clinical crown height to facilitate restorative treatment. Crown lengthening is a surgical procedure aimed at the removal of gingival tissue with or without adjunctive bone removal. The different types of procedure undertaken will be discussed over the two papers. In order to provide predictable restorations, care must be taken to ensure the integrity of the margins. If this is not taken into account it can lead to an impingement on the biologic width, which may in turn lead to chronic inflammation resulting in recession or the development of periodontal problems which can be hard to manage. Clinical Relevance: This paper aims to reinforce the need for thorough diagnosis and treatment planning and provides an overview of the various procedures that can be undertaken.

  5. Adaptive sports technology and biomechanics: prosthetics.

    Science.gov (United States)

    De Luigi, Arthur Jason; Cooper, Rory A

    2014-08-01

    With the technologic advances in medicine and an emphasis on maintaining physical fitness, the population of athletes with impairments is growing. It is incumbent upon health care practitioners to make every effort to inform these individuals of growing and diverse opportunities and to encourage safe exercise and athletic participation through counseling and education. Given the opportunities for participation in sports for persons with a limb deficiency, the demand for new, innovative prosthetic designs is challenging the clinical and technical expertise of the physician and prosthetist. When generating a prosthetic prescription, physicians and prosthetists should consider the needs and preferences of the athlete with limb deficiency, as well as the functional demands of the chosen sporting activity. The intent of this article is to provide information regarding the current advancements in the adaptive sports technology and biomechanics in the field of prosthetics, and to assist clinicians and their patients in facilitating participation in sporting activities.

  6. 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.

  7. Awake surgery between art and science. Part I: clinical and operative settings.

    Science.gov (United States)

    Talacchi, Andrea; Santini, Barbara; Casagrande, Francesca; Alessandrini, Franco; Zoccatelli, Giada; Squintani, Giovanna M

    2013-01-01

    Awake surgery requires coordinated teamwork and communication between the surgeon and the anesthesiologist, as he monitors the patient, the neuroradiologist as he interprets the images for intraoperative confirmation, and the neuropsychologist and neurophysiologist as they evaluate in real-time the patient's responses to commands and questions. To improve comparison across published studies on clinical assessment and operative settings in awake surgery, we reviewed the literature, focusing on methodological differences and aims. In complex, interdisciplinary medical care, such differences can affect the outcome and the cost-benefit ratio of the treatment. Standardization of intraoperative mapping and related controversies will be discussed in Part II.

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

    Institute of Scientific and Technical Information of China (English)

    苏英锋; 孙秀珍

    2015-01-01

    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用进行讨论,对现今建立人体器官生物数值模型研究价值进行探索与展望。%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

  9. 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.

  10. BIOMECHANICAL ANALYSIS OF RUNNING IN THE HIGH JUMP

    Directory of Open Access Journals (Sweden)

    Leite Werlayne

    2013-02-01

    Full Text Available The aim of this paper is to analyze the biomechanics of running at high jump. To this study was realized a bibliographic revision. The running phase is the one which starts when the athlete is set in movement for the jump until the moment that he touches the ground with the takeoff foot in front of the bar, this phase can be divided into two parts: the running in straight line and the running in curve. On the other hand, for better understanding and due to a biomechanical complexity, the running in curve will be divided into three other parts: the three last strides, the two last strides and the last strides. Besides that, we could mention important factors for an efficient approach run: the radius of the curve, the distance and length of the takeoff run.

  11. The Biomechanics of Cervical Spondylosis

    Directory of Open Access Journals (Sweden)

    Lisa A. Ferrara

    2012-01-01

    Full Text Available Aging is the major risk factor that contributes to the onset of cervical spondylosis. Several acute and chronic symptoms can occur that start with neck pain and may progress into cervical radiculopathy. Eventually, the degenerative cascade causes desiccation of the intervertebral disc resulting in height loss along the ventral margin of the cervical spine. This causes ventral angulation and eventual loss of lordosis, with compression of the neural and vascular structures. The altered posture of the cervical spine will progress into kyphosis and continue if the load balance and lordosis is not restored. The content of this paper will address the physiological and biomechanical pathways leading to cervical spondylosis and the biomechanical principles related to the surgical correction and treatment of kyphotic progression.

  12. The biomechanics of cervical spondylosis.

    Science.gov (United States)

    Ferrara, Lisa A

    2012-01-01

    Aging is the major risk factor that contributes to the onset of cervical spondylosis. Several acute and chronic symptoms can occur that start with neck pain and may progress into cervical radiculopathy. Eventually, the degenerative cascade causes desiccation of the intervertebral disc resulting in height loss along the ventral margin of the cervical spine. This causes ventral angulation and eventual loss of lordosis, with compression of the neural and vascular structures. The altered posture of the cervical spine will progress into kyphosis and continue if the load balance and lordosis is not restored. The content of this paper will address the physiological and biomechanical pathways leading to cervical spondylosis and the biomechanical principles related to the surgical correction and treatment of kyphotic progression.

  13. Biomechanics of Gait during Pregnancy

    OpenAIRE

    2014-01-01

    Introduction. During pregnancy women experience several changes in the body’s physiology, morphology, and hormonal system. These changes may affect the balance and body stability and can cause discomfort and pain. The adaptations of the musculoskeletal system due to morphological changes during pregnancy are not fully understood. Few studies clarify the biomechanical changes of gait that occur during pregnancy and in postpartum period. Purposes. The purpose of this re...

  14. State-of-the-art human gene therapy: part II. Gene therapy strategies and clinical applications.

    Science.gov (United States)

    Wang, Dan; Gao, Guangping

    2014-09-01

    In Part I of this Review (Wang and Gao, 2014), we introduced recent advances in gene delivery technologies and explained how they have powered some of the current human gene therapy applications. In Part II, we expand the discussion on gene therapy applications, focusing on some of the most exciting clinical uses. To help readers to grasp the essence and to better organize the diverse applications, we categorize them under four gene therapy strategies: (1) gene replacement therapy for monogenic diseases, (2) gene addition for complex disorders and infectious diseases, (3) gene expression alteration targeting RNA, and (4) gene editing to introduce targeted changes in host genome. Human gene therapy started with the simple idea that replacing a faulty gene with a functional copy can cure a disease. It has been a long and bumpy road to finally translate this seemingly straightforward concept into reality. As many disease mechanisms unraveled, gene therapists have employed a gene addition strategy backed by a deep knowledge of what goes wrong in diseases and how to harness host cellular machinery to battle against diseases. Breakthroughs in other biotechnologies, such as RNA interference and genome editing by chimeric nucleases, have the potential to be integrated into gene therapy. Although clinical trials utilizing these new technologies are currently sparse, these innovations are expected to greatly broaden the scope of gene therapy in the near future.

  15. Biomechanics of Pediatric Manual Wheelchair Mobility

    OpenAIRE

    2015-01-01

    Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting and stopping tasks. A Vicon motion analysis system ...

  16. 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...

  17. Tardive Dyskinesia Revisited: A Clinical Priority Perspective-Diagnosis and Assessment (Part A

    Directory of Open Access Journals (Sweden)

    Vernon M Neppe

    2016-06-01

    Full Text Available In this series of papers under the umbrella of tardive dyskinesia (TD, five major related issues are discussed pertaining to TD. These are integrated together. In Part A we evaluate how to diagnose, screen for physical signs and scales for tardive dyskinesia, and in Part B, we focus on the management. Tardive dyskinesia (TD is a relatively new condition associated with abnormal involuntary movements caused by or aggravated by so-called “neuroleptic” drugs. Neuroleptics are used to manage psychotic conditions, as well as nausea and acid reflux, and latterly are prescribed as adjunct medications to depression and anxiety. Tardive dyskinesia (TD has also become a major problem forensically, because of the challenge of management, the lack of patient’s being appropriately warned, and insufficient monitoring of patients at risk. In this Part A series of articles we examine several special important priorities in TD. a. First, what is tardive dyskinesia and how does one make the diagnosis? b. The second issue is the need to regularly evaluate patients on neuroleptics because they are at risk for tardive dyskinesia. Measuring and monitoring for symptoms of tardive dyskinesia allows ensuring early detection. The author’s clinical STRAW test has thus far been seldom used, but it may be the best way to monitor TD over time. It appears an improvement over the standard test, the AIMS, as it is broader in ranking (0-10 and is the only scale that measures both frequency and severity, so that monitoring of change is more sensitive. In the series that follows, Part B, we emphasize management and theory, particularly high dose buspirone management, justify the dopamine super sensitivity hypothesis, and re-evaluate the neuroleptics in that context. e1

  18. 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

    collected among nursing students by focus group interviews. Findings: Nursing students increased knowledge of both own and other professions. Similarly, they realised the importance of inter-professional teamwork. However, they problematized that it was difficult to see the relevance and to 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 skills....... It is, however, important to stress the importance of basic nursing tasks being the foundation for nursing assessments in the final part of the education....

  19. Biomechanical researches on tissue engineering bone constructed by deproteinated bone

    Institute of Scientific and Technical Information of China (English)

    JIAN Yue-kui; TIAN Xiao-bin; LI Qi-hong; LI Bo; PENG Zhi; ZHAO Wei-feng; WANG Yuan-zheng; YANG Zhen

    2010-01-01

    Objective:To study biomechanical changes of newly formed bones 24 weeks after repairing large defects of long bones of goats using heterogeneous deproteinated bone(DPB)prepared by modified methods as an engineering scaffold.Methods:According to a fully randomized design,18 goats were evenly divided into three groups:normal bone control group(Group A),autologous bone group(Group B)and experimental group(Group C).Each goat in Groups B and C were subjected to the periosteum and bone defect at middle-lower part of the fight tibia(20% of the whole tibia in length),followed by autologous bone or DPB plus autologous MSCs + rhBMP2 implantation,respectively and semiring slot fixation;while goats in Group A did not perform osteotomy.At 24 weeks after surgery,biomechanical tests were carried out on the tibias.Results:At 24 weeks after surgery,the results of anticompression test on tibias in three groups were recorded by a functional recorder presented as linear pressure-deformation curve.The shapes of the curves and their change tendency were similar among three groups.The ultimate pressure values were 10.74 Mpa±1.23 Mpa,10.11 Mpa±1.35 Mpa and 10.22 Mpa±1.32 Mpa and fracture compression rates were 26.82%±0.87%,27.17%±0.75% and 28.22%±1.12% in Groups A,B and C,respectively.Comparisons of anti-compression ultimate pressures and fracture compression rates among three groups demonstrated no significant difference(P_(AB)=0.415,P_(BC)=0.494).Three-point antibend test on tibias was recorded as load-deformation curves,and the shapes of the curves and their change tendency were similar among three groups.The ultimate pressure values of the anti-bend test were 481.52 N±12.45 N,478.34 N±14.68 N and 475.62 N±13.41 N and the fracture bend rates were 2.62 mm±0.12 mm,2.61 mm±0.15 mm and 2.81 mm±0.13 mm in Groups A,B and C,respectively.There was no significant difference between groups(P_(AB)=0.7,P_(BC)=0.448).The ultirates were 29.51°±1.64°,28.88°±1.46° and 28.81°±1.33

  20. Fractals in the neurosciences, Part II: clinical applications and future perspectives.

    Science.gov (United States)

    Di Ieva, Antonio; Esteban, Francisco J; Grizzi, Fabio; Klonowski, Wlodzimierz; Martín-Landrove, Miguel

    2015-02-01

    It has been ascertained that the human brain is a complex system studied at multiple scales, from neurons and microcircuits to macronetworks. The brain is characterized by a hierarchical organization that gives rise to its highly topological and functional complexity. Over the last decades, fractal geometry has been shown as a universal tool for the analysis and quantification of the geometric complexity of natural objects, including the brain. The fractal dimension has been identified as a quantitative parameter for the evaluation of the roughness of neural structures, the estimation of time series, and the description of patterns, thus able to discriminate different states of the brain in its entire physiopathological spectrum. Fractal-based computational analyses have been applied to the neurosciences, particularly in the field of clinical neurosciences including neuroimaging and neuroradiology, neurology and neurosurgery, psychiatry and psychology, and neuro-oncology and neuropathology. After a review of the basic concepts of fractal analysis and its main applications to the basic neurosciences in part I of this series, here, we review the main applications of fractals to the clinical neurosciences for a holistic approach towards a fractal geometry model of the brain.

  1. Biomechanics of climbing palms and how they climb.

    Science.gov (United States)

    Rowe, Nick; Isnard, Sandrine

    2009-09-01

    Climbing plants have fascinated botanists since the pioneering works of Darwin and his contemporaries in the 19(th) century. Diverse plants have evolved different ways of climbing and a wide range of attachment devices and stem biomechanics to cope with the particular physical demands of life as a climber. We investigated the biomechanics of attachment in a range of climbing palms, including true rattans from Southeast Asia and the genus Desmoncus from South America. We found that hook strength and orientation is coordinated with rachis geometry and rigidity. These findings support the notion of a ratchet-type attachment mechanism and partly explain why these spiny plants are so catchy and efficient at attaching to supports.

  2. Multiscale modeling methods in biomechanics.

    Science.gov (United States)

    Bhattacharya, Pinaki; Viceconti, Marco

    2017-01-19

    More and more frequently, computational biomechanics deals with problems where the portion of physical reality to be modeled spans over such a large range of spatial and temporal dimensions, that it is impossible to represent it as a single space-time continuum. We are forced to consider multiple space-time continua, each representing the phenomenon of interest at a characteristic space-time scale. Multiscale models describe a complex process across multiple scales, and account for how quantities transform as we move from one scale to another. This review offers a set of definitions for this emerging field, and provides a brief summary of the most recent developments on multiscale modeling in biomechanics. Of all possible perspectives, we chose that of the modeling intent, which vastly affect the nature and the structure of each research activity. To the purpose we organized all papers reviewed in three categories: 'causal confirmation,' where multiscale models are used as materializations of the causation theories; 'predictive accuracy,' where multiscale modeling is aimed to improve the predictive accuracy; and 'determination of effect,' where multiscale modeling is used to model how a change at one scale manifests in an effect at another radically different space-time scale. Consistent with how the volume of computational biomechanics research is distributed across application targets, we extensively reviewed papers targeting the musculoskeletal and the cardiovascular systems, and covered only a few exemplary papers targeting other organ systems. The review shows a research subdomain still in its infancy, where causal confirmation papers remain the most common. For further resources related to this article, please visit the WIREs website.

  3. Exploring the biomechanics of taurodontism

    Science.gov (United States)

    Benazzi, Stefano; Nguyen, Huynh N; Kullmer, Ottmar; Hublin, Jean-Jacques

    2015-01-01

    Taurodontism (i.e. enlarged pulp chamber with concomitant apical displacement of the root bi/trifurcation) is considered a dental anomaly with relatively low incidence in contemporary societies, but it represents a typical trait frequently found in Neandertal teeth. Four hypotheses can be envisioned to explain the high frequency in Neandertals: adaptation to a specific occlusal loading regime (biomechanical advantage), adaptation to a high attrition diet, pleiotropic or genetic drift effects. In this contribution we used finite element analysis (FEA) and advanced loading concepts based on macrowear information to evaluate whether taurodontism supplies some dental biomechanical advantages. Loads were applied to the digital model of the lower right first molar (RM1) of the Neandertal specimen Le Moustier 1, as well as to the digital models of both a shortened and a hyper-taurodontic version of Le Moustier RM1. Moreover, we simulated a scenario where an object is held between teeth and pulled in different directions to investigate whether taurodontism might be useful for para-masticatory activities. Our results do not show any meaningful difference among all the simulations, pointing out that taurodontism does not improve the functional biomechanics of the tooth and does not favour para-masticatory pulling activities. Therefore, taurodontism should be considered either an adaptation to a high attrition diet or most likely the result of pleiotropic or genetic drift effects. Finally, our results have important implications for modern dentistry during endodontic treatments, as we observed that filling the pulp chamber with dentine-like material increases tooth stiffness, and ultimately tensile stresses in the crown, thus favouring tooth failure. PMID:25407030

  4. 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.

  5. Fruit biomechanics based on anatomy: a review

    Science.gov (United States)

    Li, Zhiguo; Yang, Hongling; Li, Pingping; Liu, Jizhan; Wang, Jizhang; Xu, Yunfeng

    2013-01-01

    Fruit biomechanics is needed for quality determination, multiscale modelling and engineering design of fruit processes and equipments. However, these determined fruit biomechanics data often have obvious differences for the same fruit or tissue. In order to investigate it, the fruit biomechanics based on anatomy was reviewed in this paper. First, the anatomical characteristics of fruit biomaterials were described at the macroscopic `tissue' level and microscopic `cellular' level. Subsequently, the factors affecting fruit biomechanics based on anatomy and the relationships between fruit biomechanics, texture and mechanical damage were summarised according to the published literature. Fruit biomechanics is mainly affected by size, number and arrangement of cells, quantity and volume of intracellular spaces, structure, thickness, chemical composition and permeability of cell walls, and pectin degradation level and turgor pressure within cells based on microanatomy. Four test methods and partial determined results of fruit biomechanics were listed and reviewed. The determined mechanical properties data of fruit are only approximate values by using the existing four test methods, owing to the fruit biomaterials being non-homogeneous and living. Lastly, further aspects for research on fruit biomechanics were proposed for the future.

  6. 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…

  7. 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).

  8. Biomechanical performance of orthopedic gloves.

    Science.gov (United States)

    Jackson, E M; Neal, J G; Williams, F M; Stern, C A; Suber, F; Thacker, J G; Edlich, R F

    1999-01-01

    The purpose of this study was to compare the biomechanical performance of commercially available orthopedic gloves to that of a single surgical glove, as well as a double glove system. The orthopedic gloves were found to be thicker than the single surgical glove. This increased thickness of the orthopedic glove was associated with a greater resistance to glove puncture. The thickest orthopedic gloves also had reduced tactile sensitivity when compared to the single surgical glove. In addition, the glove donning forces and glove hydration rates varied considerably. These latter biomechanical performance parameters were not significantly related to glove thickness. The double glove systems tested in this study had similar performance characteristics in regard to many of the orthopedic gloves. The glove donning forces for the double glove systems were the lowest of the gloves tested. In addition, the double glove systems displayed the greatest resistance to glove hydration of the gloves tested. Their performance in the glove hydration tests and the force required to don the double glove systems were much more desirable than any of the orthopedic gloves. The results of this study indicate that the double glove systems may provide a desirable alternative to the use of the single orthopedic gloves.

  9. 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.

  10. Graphic-based musculoskeletal model for biomechanical analyses and animation.

    Science.gov (United States)

    Chao, Edmund Y S

    2003-04-01

    The ability to combine physiology and engineering analyses with computer sciences has opened the door to the possibility of creating the 'Virtual Human' reality. This paper presents a broad foundation for a full-featured biomechanical simulator for the human musculoskeletal system physiology. This simulation technology unites the expertise in biomechanical analysis and graphic modeling to investigate joint and connective tissue mechanics at the structural level and to visualize the results in both static and animated forms together with the model. Adaptable anatomical models including prosthetic implants and fracture fixation devices and a robust computational infrastructure for static, kinematic, kinetic, and stress analyses under varying boundary and loading conditions are incorporated on a common platform, the VIMS (Virtual Interactive Musculoskeletal System). Within this software system, a manageable database containing long bone dimensions, connective tissue material properties and a library of skeletal joint system functional activities and loading conditions are also available and they can easily be modified, updated and expanded. Application software is also available to allow end-users to perform biomechanical analyses interactively. This paper details the design, capabilities, and features of the VIMS development at Johns Hopkins University, an effort possible only through academic and commercial collaborations. Examples using these models and the computational algorithms in a virtual laboratory environment are used to demonstrate the utility of this unique database and simulation technology. This integrated system will impact on medical education, basic research, device development and application, and clinical patient care related to musculoskeletal diseases, trauma, and rehabilitation.

  11. 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.

  12. CLINICAL APPLICATION OF SHOCK WAVE THERAPY IN MUSCULOSKELETAL DISORDERS: PART I.

    Science.gov (United States)

    Saggini, R; Di Stefano, A; Saggini, A; Bellomo, R G

    2015-01-01

    The shock wave has been widely recognized in literature as a biological regulator; therefore we carried out a review on the activity performed by shock waves on the bone-myofascial tissue system. To date, the application of Shock Wave Therapy (SWT) in musculoskeletal disorders has been primarily used in the treatment of tendinopathies (proximal plantar fasciopathy, lateral elbow tendinopathy, calcific tendinopathy of the shoulder, and patellar tendinopathy, etc.) and bone defects (delayed- and non-union of bone fractures, avascular necrosis of femoral head, etc.). Although the mechanism of their therapeutic effects is still unknown, the majority of published papers have shown positive and beneficial effects of using SWT as a treatment for musculoskeletal disorders, with a success rate ranging from 65 to 91%, while the complications are low or negligible. The purpose of this paper is to inform the reader about the published data on the clinical application of SWT in the treatment of musculoskeletal disorders. In this paper, with the help of a literature review, indications and success rates for SWT in the treatment of musculoskeletal disorders are outlined, while adequate SWT parameters (e.g., rate of impulses, energy flux density, etc.) are defined according to the present state of knowledge. Given the abundance of the argument, it seems appropriate to subdivide the review into two parts, the first concerning the evidence of Extracorporeal Shock Wave Therapy (ESWT) on bone disorders, the second concerning findings on tendon and muscle treatment.

  13. Inside the 2016 American Society of Clinical Oncology Genitourinary Cancers Symposium: part 2 - prostate and bladder cancer.

    Science.gov (United States)

    Buti, Sebastiano; Ciccarese, Chiara; Iacovelli, Roberto; Bersanelli, Melissa; Scarpelli, Marina; Lopez-Beltran, Antonio; Cheng, Liang; Montironi, Rodolfo; Tortora, Giampaolo; Massari, Francesco

    2016-09-01

    The American Society of Clinical Oncology Genitourinary Cancers Symposium, Moscone West Building, San Francisco, CA, USA, 7-9 January 2016 The American Society of Clinical Oncology (ASCO) Genitourinary Cancers Symposium, held in San Francisco (CA, USA), from 7 to 9 January 2016, focused on 'patient-centric care: translating research to results'. Every year, this meeting is a must for anyone studying genitourinary tumors to keep abreast of the most recent innovations in this field, exchange views on behaviors customarily adopted in daily clinical practice and discuss future topics of scientific research. This two-part report highlights the key themes presented at the 2016 ASCO Genitourinary Cancers Symposium, with part 1 reporting the main novelties of kidney cancer and part 2 discussing the most relevant issues which have emerged for bladder and prostate tumors.

  14. Biomechanics and analysis of running gait.

    Science.gov (United States)

    Dugan, Sheila A; Bhat, Krishna P

    2005-08-01

    Physical activity, including running, is important to general health by way of prevention of chronic illnesses and their precursors. To keep runners healthy, it is paramount that one has sound knowledge of the biomechanics of running and assessment of running gait. More so, improving performance in competitive runners is based in sound training and rehabilitation practices that are rooted firmly in biomechanical principles. This article summarized the biomechanics of running and the means with which one can evaluate running gait. The gait assessment techniques for collecting and analyzing kinetic and kinematic data can provide insights into injury prevention and treatment and performance enhancement.

  15. 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.

  16. 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.

  17. Investigation of the influence of design details on short implant biomechanics using colorimetric photoelastic analysis: a pilot study

    OpenAIRE

    Zielak, João César; Archetti, Felipe Belmonte; Scotton,Ricardo; Filietaz,Marcelo; Carmen Lucia Mueller STORRER; Giovanini,Allan Fernando; Tatiana Miranda DELIBERADOR

    2015-01-01

    Introduction : The clinical survival of a dental implant is directly related to its biomechanical behavior. Since short implants present lower bone/implant contact area, their design may be more critical to stress distribution to surrounding tissues. Photoelastic analysis is a biomechanical method that uses either simple qualitative results or complex calculations for the acquisition of quantitative data. In order to simplify data acquisition, we performed a pilot study to demonstrate the inv...

  18. 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...

  19. Biomechanics of knife stab attacks.

    Science.gov (United States)

    Chadwick, E K; Nicol, A C; Lane, J V; Gray, T G

    1999-10-25

    Equipment, materials and methods for the measurement of the biomechanical parameters governing knife stab attacks have been developed and data have been presented that are relevant to the improvement of standards for the testing of stab-resistant materials. A six-camera Vicon motion analysis system was used to measure velocity, and derive energy and momentum during the approach phase of the attack and a specially developed force-measuring knife was used to measure three-dimensional forces and torque during the impact phase. The body segments associated with the knife were modelled as a series of rigid segments: trunk, upper arm, forearm and hand. The velocities of these segments, together with knowledge of the mass distribution from biomechanical tables, allowed the calculation of the individual segment energy and momentum values. The instrumented knife measured four components of load: axial force (along the length of the blade), cutting force (parallel to the breadth of the blade), lateral force (across the blade) and torque (twisting action) using foil strain gauges. Twenty volunteers were asked to stab a target with near maximal effort. Three styles of stab were used: a short thrust forward, a horizontal style sweep around the body and an overhand stab. These styles were chosen based on reported incidents, providing more realistic data than had previously existed. The 95th percentile values for axial force and energy were 1885 N and 69 J, respectively. The ability of current test methods to reproduce the mechanical parameters measured in human stab attacks has been assessed. It was found that current test methods could reproduce the range of energy and force values measured in the human stab attacks, although the simulation was not accurate in some respects. Non-axial force and torque values were also found to be significant in the human tests, but these are not reproduced in the standard mechanical tests.

  20. Elbow joint biomechanics for preclinical evaluation of total elbow prostheses.

    Science.gov (United States)

    Kincaid, Brian L; An, Kai-Nan

    2013-09-27

    Total elbow arthroplasty is a clinically successful procedure, yet long-term implant survival rates have historically lagged behind those reported for total hips and knees. Clinical complications associated with implant wear, osteolysis, stem loosening and device fracture have been implicated as reasons for limited long-term survivorship. Unfortunately, there is little published information on the biomechanics and method(s) for preclinical evaluation of total elbow prostheses that could provide insight into the mechanisms of failure. Additionally, there are no consensus testing standards or summaries of loading profiles of the humero-ulnar joint associated with a range of activities of daily living. Such data would facilitate the standardized preclinical assessment of total elbow devices such is commonplace for other large joints. The objective of the work here is therefore to provide a comprehensive review of elbow joint biomechanics as it relates to preclinical evaluation of total elbow implants. This summary includes a review of elbow joint forces, kinematics, the types and frequency of humero-ulnar joint motions associated with activities of daily living and clinical outcomes, as well as proposing a methodology for deriving humero-ulnar joint reaction force magnitudes and vector orientations as a function of a known mass/force at the hand. From these data, a scalable, bi-axial loading profile is proposed as a foundation for the development of clinically relevant, laboratory simulations for assessment of total elbow prostheses performance.

  1. THE CENTER FOR MILITARY BIOMECHANICS RESEARCH

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for Military Biomechanics Research is a 7,500 ft2 dedicated laboratory outfitted with state-of-the-art equipment for 3-D analysis of movement, measurement...

  2. Biomechanical patterns of text-message distraction.

    Science.gov (United States)

    Le, Peter; Hwang, Jaejin; Grawe, Sarah; Li, Jing; Snyder, Alison; Lee, Christina; Marras, William S

    2015-01-01

    The objective of this study was to identify biomechanical measures that can distinguish texting distraction in a laboratory-simulated driving environment. The goal would be to use this information to provide an intervention for risky driving behaviour. Sixteen subjects participated in this study. Three independent variables were tested: task (texting, visual targeting, weighted and non-weighted movements), task direction (front and side) and task distance (close and far). Dependent variables consisted of biomechanical moments, head displacement and the length of time to complete each task. Results revealed that the time to complete each task was higher for texting compared to other tasks. Peak moments during texting were only distinguishable from visual targeting. Peak head displacement and cumulative biomechanical exposure measures indicated that texting can be distinguished from other tasks. Therefore, it may be useful to take into account both temporal and biomechanical measures when considering warning systems to detect texting distraction.

  3. Biomechanical study of intervertebral disc degeneration

    OpenAIRE

    González Guitiérrez, Ramiro Arturo

    2012-01-01

    Degeneration and age affect the biomechanics of the intervertebral disc, by reducing its stiffness, flexibility and shock absorption capacities against daily movement and spinal load. The biomechanical characterization of intervertebral discs is achieved by conducting mechanical testing to vertebra-disc-vertebra segments and applying axial, shear, bend and torsion loads, statically or dynamically, with load magnitudes corresponding to the physiological range. However, traditional testing does...

  4. Harnessing Biomechanics to Develop Cartilage Regeneration Strategies

    OpenAIRE

    Athanasiou, KA; Responte, DJ; Brown, WE; Hu, JC

    2015-01-01

    Copyright © 2015 by ASME. As this review was prepared specifically for the American Society of Mechanical Engineers H.R. Lissner Medal, it primarily discusses work toward cartilage regeneration performed in Dr. Kyriacos A. Athanasiou's laboratory over the past 25 years. The prevalence and severity of degeneration of articular cartilage, a tissue whose main function is largely biomechanical, have motivated the development of cartilage tissue engineering approaches informed by biomechanics. Thi...

  5. Community health clinical education in Canada: part 1--"state of the art".

    Science.gov (United States)

    Cohen, Benita E; Gregory, David

    2009-01-01

    This paper presents the findings of a survey of community health clinical education in twenty-four Canadian pre-licensure baccalaureate nursing programs. A qualitative research design was used, involving a content analysis of Canadian course syllabi and supporting documents for community health courses. This study afforded a cross-sectional understanding of the "state of the art" of community health clinical education in Canadian schools of nursing. Clinical course conceptual approaches, course objectives, types of clinical sites, format and number of clinical hours, and methods of student evaluation are identified. The findings suggest the need for a national dialogue or consensus building exercise regarding curriculum content for community health nursing. Informing this dialogue are several strengths including the current focus on community health (as opposed to community-based) nursing education, and a solid socio-environmental perspective informing clinical learning and practice. The national data set generated by this study may have relevance to nursing programs globally.

  6. Biomechanics of high-grade spondylolisthesis with and without reduction.

    Science.gov (United States)

    Wang, Wenhai; Aubin, Carl-Eric; Cahill, Patrick; Baran, George; Arnoux, Pierre-Jean; Parent, Stefan; Labelle, Hubert

    2016-04-01

    The clinical advantages of reducing spondylolisthesis over fusion in situ have several intuitive reasons such as restore the spinal column into a more anatomic relationship and alignment. However, there is only little evidence in the literature supporting the theoretical advantages of reduction, and its effect on spinopelvic alignment remains poorly defined. In this study, a comprehensive finite element model was developed to analyze the biomechanics of the spine after spinal fusion at L5-S1 in both types of high-grade spondylolisthesis (balanced and unbalanced pelvis). The relevant clinical indices (i.e. spondylolisthesis grade and Dubousset lumbosacral angle), the displacement of L4-L5, pressure within the annulus and nucleus, and stress at L4-L5 were evaluated and compared. The model can well predict the changes of the important clinical indices during the surgery. For a balanced pelvis, the reduction has a minimal effect on the biomechanical conditions at the adjacent level during postsurgical activities. In the unbalanced case, reduction induced larger deformation in the lumbosacral region and a higher stress concentration at adjacent level. Whether such a stress concentration can lead to long-term disc degeneration is not known. The results provide additional information for the clinician considering reduction of high-grade spondylolisthesis.

  7. Cementless anatomical prosthesis for the treatment of 3-part and 4-part proximal humerus fractures: cadaver study and prospective clinical study with minimum 2 years followup

    Directory of Open Access Journals (Sweden)

    Obert Laurent

    2016-01-01

    Full Text Available Introduction: The purpose of this study was to evaluate the functional and radiological outcomes of a cementless, trauma-specific locked stem for 3- and 4-part proximal humeral fractures. Materials and methods: This study consisted of two parts: a cadaver study with 22 shoulders and a multicenter prospective clinical study of 23 fracture patients evaluated at least 2 years after treatment. In the cadaver study, the locked stem (HumelockTM, FX Solutions and its instrumentation were evaluated. In the clinical study, five senior surgeons at four different hospitals performed the surgical procedures. An independent surgeon evaluated the patients using clinical (Constant score, QuickDASH and radiological (X-rays, CT scans outcome measures. Results: The cadaver study allowed us to validate the height landmarks relative to the pectoralis major tendon. In the clinical study, at the review, abduction was 95° (60–160, forward flexion was 108° (70–160, external rotation (elbow at body was 34° (0–55, the QuickDASH was 31 (4.5–59, the overall Constant score was 54 (27–75, and the weighted Constant score was 76 (31.5–109. Discussion: This preliminary study of hemiarthroplasty (HA with a locked stem found results that were at least equivalent to published series. As all patients had at least a 2-year follow-up, integration of the locked stem did not cause any specific complications. These results suggest that it is possible to avoid using cement when hemiarthroplasty is performed for the humeral stem. This implant makes height adjustment and transosseous suturing of the tuberosities more reproducible.

  8. The clinical physiology of water metabolism. Part II: Renal mechanisms for urinary concentration; diabetes insipidus.

    Science.gov (United States)

    Weitzman, R E; Kleeman, C R

    1979-12-01

    The renal reabsorption of water independent of solute is the result of the coordinated function of the collecting duct and the ascending limb of the loop of Henle. The unique juxtaposition of the ascending and descending portions of the loop of Henle and of the vasa recta permits the function of a counter-current multiplier system in which water is removed from the tubular lumen and reabsorbed into the circulation. The driving force for reabsorption is the osmotic gradient in the renal medulla which is dependent, in part, on chloride (followed by sodium) pumping from the thick ascending loop of Henle. Urea trapping is also thought to play an important role in the generation of a hypertonic medullary interstitium. Arginine vasopressin (AVP) acts by binding to receptors on the cell membrane and activating adenylate cyclase. This, inturn, results in the intracellular accumulation of cyclic adenosine monophosphate (AMP) which in some fashion abruptly increases the water permeability of the luminal membrane of cells in the collecting duct. As a consequence, water flows along an osmotic gradient out of the tubular lumen into the medullary interstitium. Diabetes insipidus is the clinical condition associated with either a deficiency of or a resistance to AVP. Central diabetes insipidus is due to diminished release of AVP following damage to either the neurosecretory nuclei or the pituitary stalk. Possible causes include idiopathic, familial, trauma, tumor, infection or vascular lesions. Patients present with polyuria, usually beginning over a period of a few days. The diagnosis is made by showing that urinary concentration is impaired after water restriction but that there is a good response to exogenous vasopressin therapy. Nephrogenic diabetes insipidus can be identified by a patient's lack of response to AVP. Nephrogenic diabetes insipidus is caused by a familial defect, although milder forms can be acquired as a result of various forms of renal disease. Central

  9. Biomechanics-based in silico medicine: the manifesto of a new science.

    Science.gov (United States)

    Viceconti, Marco

    2015-01-21

    In this perspective article we discuss the role of contemporary biomechanics in the light of recent applications such as the development of the so-called Virtual Physiological Human technologies for physiology-based in silico medicine. In order to build Virtual Physiological Human (VPH) models, computer models that capture and integrate the complex systemic dynamics of living organisms across radically different space-time scales, we need to re-formulate a vast body of existing biology and physiology knowledge so that it is formulated as a quantitative hypothesis, which can be expressed in mathematical terms. Once the predictive accuracy of these models is confirmed against controlled experiments and against clinical observations, we will have VPH model that can reliably predict certain quantitative changes in health status of a given patient, but also, more important, we will have a theory, in the true meaning this word has in the scientific method. In this scenario, biomechanics plays a very important role, biomechanics is one of the few areas of life sciences where we attempt to build full mechanistic explanations based on quantitative observations, in other words, we investigate living organisms like physical systems. This is in our opinion a Copernican revolution, around which the scope of biomechanics should be re-defined. Thus, we propose a new definition for our research domain "Biomechanics is the study of living organisms as mechanistic systems".

  10. Authorship and sampling practice in selected biomechanics and sports science journals.

    Science.gov (United States)

    Knudson, Duane V

    2011-06-01

    In some biomedical sciences, changes in patterns of collaboration and authorship have complicated the assignment of credit and responsibility for research. It is unclear if this problem of "promiscuous coauthorship" or "hyperauthorship" (defined as six or more authors) is also apparent in the applied research disciplines within sport and exercise science. This study documented the authorship and sampling of patterns of original research reports in three applied biomechanics (Clinical Biomechanics, Journal of Applied Biomechanics, and Sports Biomechanics) and five similar subdisciplinary journals within sport and exercise science (International Journal of Sports Physiology and Performance, Journal of Sport Rehabilitation, Journal of Teaching Physical Education, Measurement in Physical Education and Exercise Sciences, and Motor Control). Original research reports from the 2009 volumes of these biomechanics and sport and exercise journals were reviewed. Single authorship of papers was rare (2.6%) in these journals, with the mean number of authors ranging from 2.7 to 4.5. Sample sizes and the ratio of sample to authors varied widely, and these variables tended not to be associated with number of authors. Original research reports published in these journals in 2009 tended to be published by small teams of collaborators, so currently there may be few problems with promiscuous coauthorship in these subdisciplines of sport and exercise science.

  11. Development and Use of Challenge Exams for Clinical Laboratory Nursing 2: Part 2 Final Report.

    Science.gov (United States)

    Hattstaedt, Mary Jane; Isaac, Margaret M.

    The report describes the development of a set of equivalency tests for students in Nursing 2 who have had prior clinical laboratory training or experience in pediatrics, obstetrics, or geriatrics. For each of the three areas the examination packet includes: the course clinical objectives, the challenge examination objectives, a self-study guide, a…

  12. 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

  13. 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.

  14. From conventional sensors to fibre optic sensors for strain and force measurements in biomechanics applications: a review.

    Science.gov (United States)

    Roriz, Paulo; Carvalho, Lídia; Frazão, Orlando; Santos, José Luís; Simões, José António

    2014-04-11

    In vivo measurement, not only in animals but also in humans, is a demanding task and is the ultimate goal in experimental biomechanics. For that purpose, measurements in vivo must be performed, under physiological conditions, to obtain a database and contribute for the development of analytical models, used to describe human biomechanics. The knowledge and control of the mechanisms involved in biomechanics will allow the optimization of the performance in different topics like in clinical procedures and rehabilitation, medical devices and sports, among others. Strain gages were first applied to bone in a live animal in 40's and in 80's for the first time were applied fibre optic sensors to perform in vivo measurements of Achilles tendon forces in man. Fibre optic sensors proven to have advantages compare to conventional sensors and a great potential for biomechanical and biomedical applications. Compared to them, they are smaller, easier to implement, minimally invasive, with lower risk of infection, highly accurate, well correlated, inexpensive and multiplexable. The aim of this review article is to give an overview about the evolution of the experimental techniques applied in biomechanics, from conventional to fibre optic sensors. In the next sections the most relevant contributions of these sensors, for strain and force in biomechanical applications, will be presented. Emphasis was given to report of in vivo experiments and clinical applications.

  15. The Objective Structured Clinical Examination (OSCE): AMEE Guide No. 81. Part I: an historical and theoretical perspective.

    Science.gov (United States)

    Khan, Kamran Z; Ramachandran, Sankaranarayanan; Gaunt, Kathryn; Pushkar, Piyush

    2013-09-01

    The Objective Structured Clinical Examination (OSCE) was first described by Harden in 1975 as an alternative to the existing methods of assessing clinical performance (Harden et al. 1975). The OSCE was designed to improve the validity and reliability of assessment of performance, which was previously assessed using the long case and short case examinations. Since then the use of the OSCE has become widespread within both undergraduate and postgraduate clinical education. We recognise that the introduction of the OSCE into an existing assessment programme is a challenging process requiring a considerable amount of theoretical and practical knowledge. The two parts of this Guide are designed to assist all those who intend implementing the OSCE into their assessment systems. Part I addresses the theoretical aspects of the OSCE, exploring its historical development, its place within the range of assessment tools and its core applications. Part II offers more practical information on the process of implementing an OSCE, including guidance on developing OSCE stations, choosing scoring rubrics, training examiners and standardised patients and managing quality assurance processes. Together we hope these two parts will act as a useful resource both for those choosing to implement the OSCE for the first time and also those wishing to quality assure their existing OSCE programme.

  16. Clinical indications for digital imaging in dento-alveolar trauma. Part 1: traumatic injuries.

    Science.gov (United States)

    Cohenca, Nestor; Simon, James H; Roges, Ramon; Morag, Yoav; Malfaz, Jose Maria

    2007-04-01

    Traumatized teeth present a clinical challenge with regard to their diagnosis, treatment plan, and prognosis. Recent developments in imaging systems have enabled clinicians to visualize structural changes effectively. Computed tomography, magnetic resonance imaging and cone beam computed tomography are among the most commonly used systems for dental and maxillofacial surgery. The purpose of this review is to describe the advantages and disadvantages of each technique and the clinical application for dento-alveolar trauma. Three clinical cases are described to illustrate the potential use of the NewTom 3G for diagnosis and treatment plan of dento-alveolar traumatic injuries.

  17. 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.

  18. 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

  19. 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

  20. On a soma-psychotic part of the personality: a clinical and theoretical approach to the somatic.

    Science.gov (United States)

    Vaslamatzis, Grigoris; Chatzistavrakis, George

    2012-04-01

    Inspired by Bion, the concept of a soma-psychotic part of the personality is suggested. The authors present four clinical vignettes to illustrate certain clinical phenomena in which the body played a key role in the patient's personal history, during the analytic process, or both. Certain aspects of analytic technique with these severely disturbed patients are briefly referred to, including the analyst's reverie and transformational capacity, and some observations made in these cases lead to tentative generalizations on mental functioning and psychosomatic unity. A theoretical model is constructed to contain both data and conclusions, and to offer a solution for the integration of the somatic in psychoanalytic theory.

  1. 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...

  2. 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...

  3. The business of palliative medicine--part 6: clinical operations in a comprehensive integrated program.

    Science.gov (United States)

    Lagman, Ruth L; Walsh, Declan; LeGrand, Susan B; Davis, Mellar P

    2011-03-01

    The medical care of individuals with advanced disease is complex and has historically been fragmented and suboptimal. Palliative medicine attempts to address these needs. The Harry R. Horvitz Center for Palliative Medicine at the Cleveland Clinic is an established comprehensive integrated program. Structured and seamless clinical operations are important to ensure the best delivery of high-quality medical care and continuity for those affected by life-limiting illness.

  4. Developmental biomechanics of the human cervical spine.

    Science.gov (United States)

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

    2013-04-05

    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 (pcervical 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.

  5. 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.

  6. 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...

  7. Biomechanics and physiology in active manual wheelchair propulsion

    NARCIS (Netherlands)

    van der Woude, L H; Veeger, DirkJan (H. E. J.); Dallmeijer, A J; Janssen, T W; Rozendaal, L A

    2001-01-01

    Manual wheelchair propulsion in daily life and sports is increasingly being studied. Initially, an engineering and physiological perspective was taken. More recently a concomitant biomechanics interest is seen. Themes of biomechanical and physiological studies today are performance enhancing aspects

  8. Clinical imaging guidelines part 4: challenges in identifying, engaging and collaborating with stakeholders.

    Science.gov (United States)

    Bettmann, Michael A; Oikarinen, Helja; Rehani, Madan; Holmberg, Ola; del Rosario Perez, Maria; Naidoo, Anusha; Do, Kyung-Hyun; Dreyer, Keith; Ebdon-Jackson, Steve

    2015-04-01

    The effective development and use of clinical imaging guidelines requires an understanding of who the stakeholders are, what their interests in the process are, and what roles they should play. If the appropriate stakeholders are not engaged in the right roles, it is unlikely that clinical imaging guidelines will be successfully developed, relied on, and actually used. Some stakeholders are obvious: for the development of clinical imaging guidelines, both imagers and those who request examinations, such as general practitioners, internists, and medical specialists, must be involved. To gain acceptance, other relevant groups are stakeholders, including medical societies, other health care professionals, insurers, health IT experts and vendors, and patients. The role of stakeholders must be dictated by their specific interest. For some, involvement in the creation of guidelines is the right role. For others, such as regulators or insurers, reviews or invitations to comment are required, and for others, such as medical educators, it is probably sufficient to provide information and create awareness. Only through a careful consideration of who the stakeholders are and what are their interests are the successful development, acceptance, and use of clinical imaging guidelines likely to occur. Future efforts must focus on collaboration, particularly among groups that create clinical imaging guidelines and those that can support their use, and on regulatory roles and mandates.

  9. 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.

  10. Bloqueio do nervo supraescapular: procedimento importante na prática clínica. Parte II Suprascapular nerve block: important procedure in clinical practice. Part II

    Directory of Open Access Journals (Sweden)

    Marcos Rassi Fernandes

    2012-08-01

    Full Text Available O bloqueio do nervo supraescapular é um método de tratamento reprodutível, confiável e extremamente efetivo no controle da dor no ombro. Esse método tem sido amplamente utilizado por profissionais na prática clínica, como reumatologistas, ortopedistas, neurologistas e especialistas em dor, na terapêutica de enfermidades crônicas, como lesão irreparável do manguito rotador, artrite reumatoide, sequelas de AVC e capsulite adesiva, o que justifica a presente revisão (Parte II. O objetivo deste estudo foi descrever as técnicas do procedimento e suas complicações descritas na literatura, já que a primeira parte reportou as indicações clínicas, drogas e volumes utilizados em aplicação única ou múltipla. Apresentamse, detalhadamente, os acessos para a realização do procedimento tanto direto como indireto, anterior e posterior, lateral e medial, e superior e inferior. Diversas são as opções para se realizar o bloqueio do nervo supraescapular. Apesar de raras, as complicações podem ocorrer. Quando bem indicado, este método deve ser considerado.The suprascapular nerve block is a reproducible, reliable, and extremely effective treatment method in shoulder pain control. This method has been widely used by professionals in clinical practice such as rheumatologists, orthopedists, neurologists, and pain specialists in the treatment of chronic diseases such as irreparable rotator cuff injury, rheumatoid arthritis, stroke sequelae, and adhesive capsulitis, which justifies the present review (Part II. The objective of this study was to describe the techniques and complications of the procedure described in the literature, as the first part reported the clinical indications, drugs, and volumes used in single or multiple procedures. We present in details the accesses used in the procedure: direct and indirect, anterior and posterior, lateral and medial, upper and lower. There are several options to perform suprascapular nerve block

  11. Mobile clinics in Haiti, part 1: Preparing for service-learning.

    Science.gov (United States)

    Cone, Pamela H; Haley, Janice M

    2016-11-01

    Mobile clinics have been used successfully to provide healthcare services to people in hard to reach areas around the world, but their use is sometimes controversial. There are advantages to using mobile clinics among rural underserved populations, and providing access to those who are vulnerable will improve health and decrease morbidity and mortality. However, some teams use inappropriate approaches to international service. For over 15 years, Azusa Pacific University School of Nursing has sponsored mobile clinics to rural northern Haiti with the aim to provide culturally sensitive healthcare in collaboration with Haitian leaders. Experience and exploring the literature have informed the APU-SoN approach on best practices for planning and preparing study abroad, service-learning trips that provide healthcare services. The authors hope that this description of the preparation and planning needed for appropriate and culturally sensitive service-learning experiences abroad will benefit others who seek to provide healthcare study abroad opportunities around the world.

  12. 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 employed...

  13. The biomechanical mechanism of how strength and power training improves walking speed in old adults remains unknown

    NARCIS (Netherlands)

    Beijersbergen, C. M. I.; Granacher, U.; Vandervoort, A. A.; DeVita, P.; Hortobagyi, T.

    2013-01-01

    Maintaining and increasing walking speed in old age is clinically important because this activity of daily living predicts functional and clinical state. We reviewed evidence for the biomechanical mechanisms of how strength and power training increase gait speed in old adults. A systematic search yi

  14. 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...

  15. 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.

  16. Primary care clinical placements: The views of Australian registered nurse mentors and pre-registration nursing students (part 2).

    Science.gov (United States)

    McInnes, Susan; Peters, Kath; Hardy, Jennifer; Halcomb, Elizabeth

    2015-11-01

    An increased burden of chronic and complex conditions treated in the community and an aging population have exacerbated the primary care workload. Predicted nursing shortages will place further stressors on this workforce. High quality clinical placements may provide a strategic pathway to introduce and recruit new nurses to this speciality. This paper is Part 2 of a two part series reporting the findings of a mixed methods project. Part 1 reported on the qualitative study and Part 2 reports on the quantitative study. Forty-five pre-registration nursing students from a single Australian tertiary institution and 22 primary care Registered Nurse (RN) mentors who supervised student learning completed an online survey. Students largely regarded their primary care placement positively and felt this to be an appropriate learning opportunity. Most RNs were satisfied with mentoring pre-registration nursing students in their setting. Furthermore, the RNs desire to mentor students and the support of general practitioners (GPs) and consumers were seen as key enablers of pre-registration nursing placements. Findings from this study provide a preliminary impression of primary care clinical placements from the perspective of pre-registration nursing students and registered nurse mentors. Further research should examine whether a broader scope of non-traditional health settings such as non-government organisations, charities, pharmacies, welfare and social services can also provide appropriate learning environments for pre-registration nursing students.

  17. Pseudoelasticity and thermoelasticity of nickel-titanium alloys: a clinically oriented review. Part II: Deactivation forces.

    Science.gov (United States)

    Santoro, M; Nicolay, O F; Cangialosi, T J

    2001-06-01

    The purpose of this review was to organize a systematic reference to help orthodontists evaluate commonly used orthodontic nickel-titanium alloys. Part I of the article reviewed the data available in the literature regarding the temperature transitional ranges of the alloys. The thermomechanical behavior of these compounds is, in fact, strictly dependent upon the correlation between the temperature transitional range and the oral temperature range. Part II focuses on the mechanical characteristics of the alloys, such as the magnitude of the forces delivered and correlations with the temperature transitional range and oral temperature.

  18. Pancreatic islet fibrosis in rock hyraxes (Procavia capensis), Part 1: Case histories, clinical pathology, and epizootiology.

    Science.gov (United States)

    Gamble, Kathryn C; Garner, Michael M; Krause, Laura; Alvarado, Thomas P

    2004-09-01

    Two adult female rock hyraxes (Procavia capensis) at the Dallas Zoo were confirmed with spontaneous diabetes mellitus from 1997-2000, whereas a third animal with a similar clinical presentation never became hyperglycemic. The pancreas in all three animals showed pancreatic islet fibrosis (PIF). Retrospective examination of medical records for rock hyraxes acquired by this collection or born into it from 1991-2002 identified eight more animals affected with PIE All affected animals, including three males and eight females, were 1-7 yr of age and presented either with vague clinical signs of soft feces and rough hair coat or were acutely moribund or dead. Clinical pathology data was available for seven of the animals before onset of overt clinical signs and revealed inappropriate hyperglycemia in six, as well as elevated serum concentrations of creatine phosphokinase, amylase, and lipase in all seven animals. Pedigree evaluation did not support a familial pattern for PIE Review of the histopathology findings from nine other zoologic collections with rock hyrax deaths during the study period identified six institutions with 12 additional cases genetically unrelated to the incident collection. Histopathology and viral serology did not support an infectious cause. Analysis of serum anti-islet and anti-insulin antibodies did not suggest autoimmune disease, and none of the animals had known exposure to toxic substances. Limited nutritional analyses did not support a nutritional basis for the condition, and the cause for PIF remains unknown.

  19. 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.

  20. 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.

  1. Mild cognitive impairment (part 1: clinical characteristics and predictors of dementia

    Directory of Open Access Journals (Sweden)

    Orestes V. Forlenza

    2013-06-01

    Full Text Available Objective: To critically review and evaluate existing knowledge on the conceptual limits and clinical usefulness of the diagnosis of mild cognitive impairment (MCI and the neuropsychological assessment and short- and long-term prognosis thereof. Methods: We conducted a systematic search of the PubMed and Web of Science electronic databases, limited to articles published in English between 1999 and 2012. Based on the search terms mild cognitive impairment or MCI and epidemiology or diagnosis, we retrieved 1,698 articles, of which 248 were critically eligible (cross-sectional and longitudinal studies; the abstracts of the remaining 1,450 articles were also reviewed. Results: A critical review on the MCI construct is provided, including conceptual and diagnostic aspects; epidemiological relevance; clinical assessment; prognosis; and outcome. The distinct definitions of cognitive impairment, MCI included, yield clinically heterogeneous groups of individuals. Those who will eventually progress to dementia may present with symptoms consistent with the definition of MCI; conversely, individuals with MCI may remain stable or return to normal cognitive function. Conclusion: On clinical grounds, the cross-sectional diagnosis of MCI has limited prognostic relevance. The characterization of persistent and/or progressive cognitive deficits over time is a better approach for identification of cases at the pre-dementia stages, particularly if these cognitive abnormalities are consistent with the natural history of incipient Alzheimer's disease.

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

    NARCIS (Netherlands)

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

    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 obt

  3. Young People's Experiences of Participation in Clinical Trials : Reasons for Taking Part

    NARCIS (Netherlands)

    Luchtenberg, Malou; Maeckelberghe, Els; Locock, Louise; Powell, Lesley; Verhagen, A. A. Eduard

    2015-01-01

    Given the lack of knowledge about safety and efficacy of many treatments for children, pediatric clinical trials are important, but recruitment for pediatric research is difficult. Little is known about children's perspective on participating in trials. The purpose of this study was to understand th

  4. 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.

  5. 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

  6. Anatomy and biomechanics of the craniovertebral junction.

    Science.gov (United States)

    Lopez, Alejandro J; Scheer, Justin K; Leibl, Kayla E; Smith, Zachary A; Dlouhy, Brian J; Dahdaleh, Nader S

    2015-04-01

    The craniovertebral junction (CVJ) has unique anatomical structures that separate it from the subaxial cervical spine. In addition to housing vital neural and vascular structures, the majority of cranial flexion, extension, and axial rotation is accomplished at the CVJ. A complex combination of osseous and ligamentous supports allow for stability despite a large degree of motion. An understanding of anatomy and biomechanics is essential to effectively evaluate and address the various pathological processes that may affect this region. Therefore, the authors present an up-to-date narrative review of CVJ anatomy, normal and pathological biomechanics, and fixation techniques.

  7. 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

  8. Costing clinical biochemistry services as part of an operational management budgeting system.

    Science.gov (United States)

    Tarbit, I F

    1986-08-01

    The process of costing clinical biochemistry tests as a component of the commissioning of a unit management budgeting system based on an International Computers Limited (ICL) minicomputer system was examined. Methods of apportioning consumable and labour costs under direct and indirect cost headings and as test and request charges were investigated, and in this currently operational system it was found that 38% of consumable costs and 57% of labour costs were not a direct component of the routine analysis function. Means of assigning test costs to a given request source and the incorporation of such charges into clinical budget statements were looked at. A reduction in laboratory workload did not produce a comparable reduction in laboratory costs. For a theoretical reduction in workload of 20% only a 3.8% laboratory saving in recoverable costs could be expected.

  9. Clinical indications for digital imaging in dento-alveolar trauma. Part 2: root resorption.

    Science.gov (United States)

    Cohenca, Nestor; Simon, James H; Mathur, Aeshna; Malfaz, Jose Maria

    2007-04-01

    Common complications of dento-alveolar trauma are pulp necrosis, pulp canal obliteration, periapical pathosis and root resorption. Different types of root resorption have been identified with traumatic injuries. Repair-related (surface), infection-related (inflammatory), ankylosis-related (osseous replacement) or extraradicular invasive cervical resorption are among the most common. Recent developments in imaging systems have enabled clinicians to visualize structural changes effectively. The diagnosis and three-dimensional imaging assessment of the resorption is important in order to determine the treatment complexity and expected outcome based on the location and extension of the root defect. This article discusses and illustrates the clinical application of cone beam computed tomography for diagnosis and treatment plan of root resorption. Four clinical cases are presented to illustrate the potential use of the NewTom 3G for root resorption.

  10. Screening, Brief Intervention, and Referral to Treatment in a rural Ryan White Part C HIV clinic.

    Science.gov (United States)

    Graham, Lucy J; Davis, Amy L; Cook, Paul F; Weber, Mary

    2016-01-01

    About 24% of people living with HIV nationally are identified as needing treatment for alcohol or illicit drug use. Screening, Brief Intervention, and Referral to Treatment (SBIRT) has evolved as a strategy to assess and intervene with substance abuse behaviors in various clinical settings. However, less is known about the processes and outcomes of using the SBIRT intervention in outpatient HIV clinics. This paper presents a descriptive analysis of de-identified existing SBIRT results data from an outpatient HIV clinic located in western Colorado. From 2008 to 2013, a total of 1616 SBIRT evaluations were done, which included duplicate patients because some individual patients were screened more than once in a given year. Over this time period, 37-49% of encounters per year were notable for tobacco use, 8-21% for alcohol use, 6-16% for marijuana use, 3-9% for amphetamine use, and 0-2% for illicit opioid use. Unique, unduplicated patient data from 2013 revealed 40% of patients used tobacco, 16% used alcohol, and 11% used methamphetamine. Analyses highlighted that the majority of our patient population (58% in 2013) used and/or abused tobacco, alcohol, and/or illicit substances. An alarming finding was the increase in methamphetamine use over time with more than 50-fold prevalence of use in our population compared to national rates.

  11. Temporomandibular joint ankylosis as part of the clinical spectrum of Carey-Fineman-Ziter syndrome?

    Science.gov (United States)

    Pasetti, Martina; Mazzoleni, Fabio; Novelli, Giorgio; Iascone, Maria; Bozzetti, Alberto; Selicorni, Angelo

    2016-08-01

    The Carey-Finema-Ziter syndrome (CFZS, MIM 254940) is an apparently autosomal recessively inherited disorder consisting of the combination of non-progressive congenital myopathy with Moebius and Pierre Robin sequence, facial anomalies and growth delay. Mental development has been described as normal or delayed. Temporomandibular joint (TMJ) ankylosis is the immobility of the joint caused by ankylotic fusion of the mandible to the cranial base or zygoma. It is a serious and disabling condition that may cause problems in mastication, digestion, speech, appearance, and oral hygiene. Most often is a true ankylosis of the TMJ but other pathological mechanisms are described (i.e., the fusion of the coronoid process to temporal bone or with the zygoma, or a variety of soft tissues disorders like Fibrodysplasia Ossificans Progressiva). Here we report a 2-year-old girl fitting with a clinical diagnosis of CFZS associated with a limited mouth opening in which temporomandibular joint ankylosis was suspected. Because it has been postulated that many clinical features in CFZS may only be secondary effects of brainstem anomalies and muscle weakness during development, the limited opening of the mouth observed in our patient could represent a rare clinical feature of CFZS itself. © 2016 Wiley Periodicals, Inc.

  12. Adapting social neuroscience measures for schizophrenia clinical trials, part 3: fathoming external validity.

    Science.gov (United States)

    Olbert, Charles M; Penn, David L; Kern, Robert S; Lee, Junghee; Horan, William P; Reise, Steven P; Ochsner, Kevin N; Marder, Stephen R; Green, Michael F

    2013-11-01

    It is unknown whether measures adapted from social neuroscience linked to specific neural systems will demonstrate relationships to external variables. Four paradigms adapted from social neuroscience were administered to 173 clinically stable outpatients with schizophrenia to determine their relationships to functionally meaningful variables and to investigate their incremental validity beyond standard measures of social and nonsocial cognition. The 4 paradigms included 2 that assess perception of nonverbal social and action cues (basic biological motion and emotion in biological motion) and 2 that involve higher level inferences about self and others' mental states (self-referential memory and empathic accuracy). Overall, social neuroscience paradigms showed significant relationships to functional capacity but weak relationships to community functioning; the paradigms also showed weak correlations to clinical symptoms. Evidence for incremental validity beyond standard measures of social and nonsocial cognition was mixed with additional predictive power shown for functional capacity but not community functioning. Of the newly adapted paradigms, the empathic accuracy task had the broadest external validity. These results underscore the difficulty of translating developments from neuroscience into clinically useful tasks with functional significance.

  13. Adapting social neuroscience measures for schizophrenia clinical trials, Part 2: trolling the depths of psychometric properties.

    Science.gov (United States)

    Kern, Robert S; Penn, David L; Lee, Junghee; Horan, William P; Reise, Steven P; Ochsner, Kevin N; Marder, Stephen R; Green, Michael F

    2013-11-01

    The psychometric properties of 4 paradigms adapted from the social neuroscience literature were evaluated to determine their suitability for use in clinical trials of schizophrenia. This 2-site study (University of California, Los Angeles and University of North Carolina) included 173 clinically stable schizophrenia outpatients and 88 healthy controls. The social cognition battery was administered twice to the schizophrenia group (baseline, 4-week retest) and once to the control group. The 4 paradigms included 2 that assess perception of nonverbal social and action cues (basic biological motion and emotion in biological motion) and 2 that involve higher level inferences about self and others' mental states (self-referential memory and empathic accuracy). Each paradigm was evaluated on (1) patient vs healthy control group differences, (2) test-retest reliability, (3) utility as a repeated measure, and (4) tolerability. Of the 4 paradigms, empathic accuracy demonstrated the strongest characteristics, including large between-group differences, adequate test-retest reliability (.72), negligible practice effects, and good tolerability ratings. The other paradigms showed weaker psychometric characteristics in their current forms. These findings highlight challenges in adapting social neuroscience paradigms for use in clinical trials.

  14. 多爪钳夹式颈椎固定器的生物力学测试及临床应用%Biomechanical Study and Clinical Application of Multiclaw Cliplike Cervical Spinal Fixator

    Institute of Scientific and Technical Information of China (English)

    黄令坚; 王以进; 等

    2001-01-01

    Objective To improve the results of treatment for cervical spine injury with a new device. Methods A new device, multiclaw cliplike spinal fixator (MSCF) was designed by authors. The experiments were performed on 10 cadaveric cervical spines to compare the biomechanical characteristic of MCSF, articular process plate and the intact Spines. Fifteen cases of lower cervical spine injury were treated with MCSF. Results MCSF had advantage over the articular process plate and the intact spines in anti-axial compression, antibending and antirotation. In the 15 cases. the cervical spine normal carvature and the height of the vertebra injuried had been restored after operation. The follow-up of 24.3 months showed there were no loosening of the device, recurence of deformation and so on. Conclusiou MCSF posseses adequate strength and good stability and the technique is simple and safe. The authors consider this device is one of ideal fixators for cervical spine and is worthy recommending.%目的 提高颈椎内固定的效果。方法自行设计一种新型的脊柱固定器(MCSF)。经临床治疗下颈椎损伤15例,并用10具新鲜尸体脊柱标本(C1~T1)进行力学测定,比较MCSF、关节突钢板及正常脊柱的生物力学特性。结果在抗轴向压缩、弯曲及旋转应力方面,MCSF明显优于关节突钢板及正常脊柱。而临床应用显示术后颈椎的生理曲线和伤椎高度完全得到恢复,平均随访时间24.3个月,未见固定器松脱及畸形矫正度丢失现象。结论MCSF符合生物力学原理,有良好的固定作用,手术操作安全简便,是颈椎后路理想的固定器之一,值得推广应用。

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

    CERN Document Server

    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 exhaustion of biochemical resources) is closely related to the Ricci flow on the biomechanical configuration manifold. Keywords: Time-dependent biomechanics, extended configuration manifold, configuration bundle, jet manifolds, Ricci flow diffusion

  16. 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

  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.

    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.

  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.

    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.

  19. 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.

  20. Stents: Biomechanics, Biomaterials, and Insights from Computational Modeling.

    Science.gov (United States)

    Karanasiou, Georgia S; Papafaklis, Michail I; Conway, Claire; Michalis, Lampros K; Tzafriri, Rami; Edelman, Elazer R; Fotiadis, Dimitrios I

    2017-04-01

    Coronary stents have revolutionized the treatment of coronary artery disease. Improvement in clinical outcomes requires detailed evaluation of the performance of stent biomechanics and the effectiveness as well as safety of biomaterials aiming at optimization of endovascular devices. Stents need to harmonize the hemodynamic environment and promote beneficial vessel healing processes with decreased thrombogenicity. Stent design variables and expansion properties are critical for vessel scaffolding. Drug-elution from stents, can help inhibit in-stent restenosis, but adds further complexity as drug release kinetics and coating formulations can dominate tissue responses. Biodegradable and bioabsorbable stents go one step further providing complete absorption over time governed by corrosion and erosion mechanisms. The advances in computing power and computational methods have enabled the application of numerical simulations and the in silico evaluation of the performance of stent devices made up of complex alloys and bioerodible materials in a range of dimensions and designs and with the capacity to retain and elute bioactive agents. This review presents the current knowledge on stent biomechanics, stent fatigue as well as drug release and mechanisms governing biodegradability focusing on the insights from computational modeling approaches.

  1. Clinical diversity of ankylosing spondylitis in the real practice of a rheumatologist in Russia (Part 1

    Directory of Open Access Journals (Sweden)

    Evgeny Vladimirovich Volnukhin

    2012-01-01

    Full Text Available Objective: to study the clinical picture of ankylosing spondylitis (AS, the association of its manifestations with the degree of disability in the real practice of a rheumatologist in Russia. Subjects and methods. The investigation enrolled 464 patients with AS, who had consecutively visited rheumatologists for 4 months in 24 cities and towns of the Russian Federation. A specially designed clinical card was filled out for all patients. Later on, the diagnosis of the disease was verified at the Research Institute of Rheumatology, Russian Academy of Medical Sciences, according to the 1984 modified New York criteria and pelvic survey X-ray films were assessed by two independent experts in a blind fashion. Results. The valid diagnosis of AS was confirmed in 330 (71.1% out of all 464 patients included into the study; their mean age was 39.7±10.2 years; the mean duration of disease was 14.6±2.6 years; 86% were men and 14% were women. About half (47% of the patients had peripheral arthritis and 56% had clinical signs of coxitis. The mean BASDAI and BASFI scores were 4.8±2.1 and 4.3±2.6, respectively. 61% of the patients had a BASDAI score of >4.0. Uveitis was the most common extravertebral manifestation (22%. One third of the patients did not work because of health reasons; 45% of the patients changed their work activities due to disease. Conclusion. In Russia, AS is characterized by its high activity, frequent involvement of hip joints and poor functional status in the patients on average 15 years after the onset of the disease. Loss of working capacity was observed in one-third of the patients. In the country, AS is diagnosed very late, on average 9 years after the disease onset.

  2. Anatomical Characteristics and Biomechanical Properties of the Oblique Popliteal Ligament

    Science.gov (United States)

    Wu, Xiang-Dong; Yu, Jin-Hui; Zou, Tao; Wang, Wei; LaPrade, Robert F.; Huang, Wei; Sun, Shan-Quan

    2017-01-01

    This anatomical study sought to investigate the morphological characteristics and biomechanical properties of the oblique popliteal ligament (OPL). Embalmed cadaveric knees were used for the study. The OPL and its surrounding structures were dissected; its morphology was carefully observed, analyzed and measured; its biomechanical properties were investigated. The origins and insertions of the OPL were relatively similar, but its overall shape was variable. The OPL had two origins: one originated from the posterior surface of the posteromedial tibia condyle, merged with fibers from the semimembranosus tendon, the other originated from the posteromedial part of the capsule. The two origins converged and coursed superolaterally, then attached to the fabella or to the tendon of the lateral head of the gastrocnemius and blended with the posterolateral joint capsule. The OPL was classified into Band-shaped, Y-shaped, Z-shaped, Trident-shaped, and Complex-shaped configurations. The mean length, width, and thickness of the OPL were 39.54, 22.59, and 1.44 mm, respectively. When an external rotation torque (18 N·m) was applied both before and after the OPL was sectioned, external rotation increased by 8.4° (P = 0.0043) on average. The OPL was found to have a significant role in preventing excessive external rotation and hyperextension of the knee. PMID:28205540

  3. WFUMB Guidelines and Recommendations on the Clinical Use of Ultrasound Elastography: Part 4. Thyroid.

    Science.gov (United States)

    Cosgrove, David; Barr, Richard; Bojunga, Joerg; Cantisani, Vito; Chammas, Maria Cristina; Dighe, Manjiri; Vinayak, Sudhir; Xu, Jun-Mei; Dietrich, Christoph F

    2017-01-01

    The World Federation for Ultrasound in Medicine and Biology (WFUMB) has produced guidelines for the use of elastography techniques including basic science, breast and liver. Here we present elastography in thyroid diseases. For each available technique, procedure, reproducibility, results and limitations are analyzed and recommendations are given. Finally, recommendations are given based on the level of evidence of the published literature and on the WFUMB expert group's consensus. The document has a clinical perspective and is aimed at assessing the usefulness of elastography in the management of thyroid diseases.

  4. 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...... 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...

  5. [Masticatory muscles. Part III. Biomechanics of the masticatory muscles].

    Science.gov (United States)

    Koolstra, J H

    1997-08-01

    The masticatory muscles are able to produce forces. These forces may cause movements of the lower jaw. Furthermore, they can be applied by the teeth for the generation of bite or chewing forces. During these kind of processes the temporomandibular joints will be loaded also. The interaction between forces and movements in the masticatory system is complex but obeys the relatively simple laws of mechanics. By application of these laws the development of joint loading, force patterns and movements during masticatory function and dysfunction can be understood. This is illustrated by a few examples of both statical and dynamical masticatory performance.

  6. 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

  7. Biomechanics of Distance Running: A Longitudinal Study

    Science.gov (United States)

    Nelson, Richard C.; Gregor, Robert J.

    1976-01-01

    Training for distance running over a long period produces meaningful changes in the running mechanics of experienced runners, as revealed in this longitudinal study of the biomechanical components of stride length, stride rate, stride time, and support and nonsupport time. (MB)

  8. 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.…

  9. Biomechanics of Pediatric Manual Wheelchair Mobility.

    Science.gov (United States)

    Slavens, Brooke A; Schnorenberg, Alyssa J; Aurit, Christine M; Tarima, Sergey; Vogel, Lawrence C; Harris, Gerald F

    2015-01-01

    Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting, and stopping tasks. A Vicon motion analysis system captured movement, while a SmartWheel simultaneously collected three-dimensional forces and moments occurring at the handrim. A custom pediatric inverse dynamics model was used to evaluate three-dimensional upper extremity joint motions, forces, and moments of 14 children with spinal cord injury (SCI) during the functional tasks. Additionally, pain and health-related quality of life outcomes were assessed. This research found that joint demands are significantly different amongst functional tasks, with greatest demands placed on the shoulder during the starting task. Propulsion was significantly different from starting and stopping at all joints. We identified multiple stroke patterns used by the children, some of which are not standard in adults. One subject reported average daily pain, which was minimal. Lower than normal physical health and higher than normal mental health was found in this population. It can be concluded that functional tasks should be considered in addition to propulsion for rehabilitation and SCI treatment planning. This research provides wheelchair users and clinicians with a comprehensive, biomechanical, mobility assessment approach for wheelchair prescription, training, and long-term care of children with SCI.

  10. 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…

  11. Surface driven biomechanical breast image registration

    Science.gov (United States)

    Eiben, Björn; Vavourakis, Vasileios; Hipwell, John H.; Kabus, Sven; Lorenz, Cristian; Buelow, Thomas; Williams, Norman R.; Keshtgar, M.; Hawkes, David J.

    2016-03-01

    Biomechanical modelling enables large deformation simulations of breast tissues under different loading conditions to be performed. Such simulations can be utilised to transform prone Magnetic Resonance (MR) images into a different patient position, such as upright or supine. We present a novel integration of biomechanical modelling with a surface registration algorithm which optimises the unknown material parameters of a biomechanical model and performs a subsequent regularised surface alignment. This allows deformations induced by effects other than gravity, such as those due to contact of the breast and MR coil, to be reversed. Correction displacements are applied to the biomechanical model enabling transformation of the original pre-surgical images to the corresponding target position. The algorithm is evaluated for the prone-to-supine case using prone MR images and the skin outline of supine Computed Tomography (CT) scans for three patients. A mean target registration error (TRE) of 10:9 mm for internal structures is achieved. For the prone-to-upright scenario, an optical 3D surface scan of one patient is used as a registration target and the nipple distances after alignment between the transformed MRI and the surface are 10:1 mm and 6:3 mm respectively.

  12. A Biomechanical Analysis of the Karate Chop.

    Science.gov (United States)

    Cavanagh, Peter R.; Landa, Jean

    Although the sport of karate has been somewhat neglected by scientists, the following two isolated biomechanical studies exist in literature: (1) tracings of a karate chop in two planes were presented, but no data was given concerning the rates of movement of the limb segments, and (2) pre- and postimpact phenomena of five subjects were studied,…

  13. Ultrasonographic assessment of carpal tunnel biomechanics

    NARCIS (Netherlands)

    van Doesburg, M.H.M.

    2012-01-01

    In this thesis, we searched for a way to assess flexor tendon and median nerve biomechanics, as well as subsynovial connective tissue thickness (SSCT) in the carpal tunnel with ultrasound, and tried to see if these patterns would give a clue towards understanding the etiology of carpal tunnel syndro

  14. Biomechanics of Pediatric Manual Wheelchair Mobility

    Science.gov (United States)

    Slavens, Brooke A.; Schnorenberg, Alyssa J.; Aurit, Christine M.; Tarima, Sergey; Vogel, Lawrence C.; Harris, Gerald F.

    2015-01-01

    Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting, and stopping tasks. A Vicon motion analysis system captured movement, while a SmartWheel simultaneously collected three-dimensional forces and moments occurring at the handrim. A custom pediatric inverse dynamics model was used to evaluate three-dimensional upper extremity joint motions, forces, and moments of 14 children with spinal cord injury (SCI) during the functional tasks. Additionally, pain and health-related quality of life outcomes were assessed. This research found that joint demands are significantly different amongst functional tasks, with greatest demands placed on the shoulder during the starting task. Propulsion was significantly different from starting and stopping at all joints. We identified multiple stroke patterns used by the children, some of which are not standard in adults. One subject reported average daily pain, which was minimal. Lower than normal physical health and higher than normal mental health was found in this population. It can be concluded that functional tasks should be considered in addition to propulsion for rehabilitation and SCI treatment planning. This research provides wheelchair users and clinicians with a comprehensive, biomechanical, mobility assessment approach for wheelchair prescription, training, and long-term care of children with SCI. PMID:26442251

  15. 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…

  16. Biomechanics of the pelvic floor musculature

    NARCIS (Netherlands)

    Janda, S.

    2006-01-01

    The present thesis was motivated by two main goals. The first research goal of the thesis was to understand the complex biomechanical behaviour of the pelvic floor muscles. The second goal was to study the mechanism of the pelvic organ prolapse (genital prolapse). The pelvic floor in humans is a ve

  17. Identifying nonlinear biomechanical models by multicriteria analysis

    Science.gov (United States)

    Srdjevic, Zorica; Cveticanin, Livija

    2012-02-01

    In this study, the methodology developed by Srdjevic and Cveticanin (International Journal of Industrial Ergonomics 34 (2004) 307-318) for the nonbiased (objective) parameter identification of the linear biomechanical model exposed to vertical vibrations is extended to the identification of n-degree of freedom (DOF) nonlinear biomechanical models. The dynamic performance of the n-DOF nonlinear model is described in terms of response functions in the frequency domain, such as the driving-point mechanical impedance and seat-to-head transmissibility function. For randomly generated parameters of the model, nonlinear equations of motion are solved using the Runge-Kutta method. The appropriate data transformation from the time-to-frequency domain is performed by a discrete Fourier transformation. Squared deviations of the response functions from the target values are used as the model performance evaluation criteria, thus shifting the problem into the multicriteria framework. The objective weights of criteria are obtained by applying the Shannon entropy concept. The suggested methodology is programmed in Pascal and tested on a 4-DOF nonlinear lumped parameter biomechanical model. The identification process over the 2000 generated sets of parameters lasts less than 20 s. The model response obtained with the imbedded identified parameters correlates well with the target values, therefore, justifying the use of the underlying concept and the mathematical instruments and numerical tools applied. It should be noted that the identified nonlinear model has an improved accuracy of the biomechanical response compared to the accuracy of a linear model.

  18. 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.

  19. ”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.

  20. Imaging of juvenile idiopathic arthritis. Part I: Clinical classifications and radiographs.

    Science.gov (United States)

    Sudoł-Szopińska, Iwona; Matuszewska, Genowefa; Gietka, Piotr; Płaza, Mateusz; Walentowska-Janowicz, Marta

    2016-09-01

    Juvenile idiopathic arthritis is the most common autoimmune systemic disease of the connective tissue affecting individuals at the developmental age. Radiography is the primary modality employed in the diagnostic imaging in order to identify changes typical of this disease entity and rule out other bone-related pathologies, such as neoplasms, posttraumatic changes, developmental defects and other forms of arthritis. The standard procedure involves the performance of comparative joint radiographs in two planes. Radiographic changes in juvenile idiopathic arthritis are detected in later stages of the disease. Bone structures are assessed in the first place. Radiographs can also indirectly indicate the presence of soft tissue inflammation (i.e. in joint cavities, sheaths and bursae) based on swelling and increased density of the soft tissue as well as dislocation of fat folds. Signs of articular cartilage defects are also seen in radiographs indirectly - based on joint space width changes. The first part of the publication presents the classification of juvenile idiopathic arthritis and discusses its radiographic images. The authors list the affected joints as well as explain the spectrum and specificity of radiographic signs resulting from inflammatory changes overlapping with those caused by the maturation of the skeletal system. Moreover, certain dilemmas associated with the monitoring of the disease are reviewed. The second part of the publication will explain issues associated with ultrasonography and magnetic resonance imaging, which are more and more commonly applied in juvenile idiopathic arthritis for early detection of pathological features as well as the disease complications.

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

    Science.gov (United States)

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

    2014-06-01

    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 review other autoinflammatory disorders including hyper IgD, tumor necrosis factor receptor-associated periodic syndrome (TRAPS), cryopyrin associated periodic syndromes, autoinflammatory bone disorders and some other rare autoinflammatory disorders such as Sweet's and Blau syndromes. In cryopyrin associated periodic syndromes group, we discussed chronic infantile neurologic cutaneous and articular (CINCA) syndrome, Muckle-Wells syndrome and familial cold autoinflammatory syndrome. Autoinflammatory bone disorders are categorized to monogenic disorders such as pyogenic arthritis, pyoderma ;gangraenosum and acne (PAPA) syndrome, the deficiency of interleukine-1 receptor antagonist (DIRA) and Majeed syndrome and polygenic background or sporadic group such as chronic recurrent multifocal osteomyelitis (CRMO) or synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome are classified in sporadic group. Other autoinflammatory syndromes are rare causes of periodic fever in Iranian system registry.

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

    Science.gov (United States)

    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 review other autoinflammatory disorders including hyper IgD, tumor necrosis factor receptor–associated periodic syndrome (TRAPS), cryopyrin associated periodic syndromes, autoinflammatory bone disorders and some other rare autoinflammatory disorders such as Sweet’s and Blau syndromes. In cryopyrin associated periodic syndromes group, we discussed chronic infantile neurologic cutaneous and articular (CINCA) syndrome, Muckle-Wells syndrome and familial cold autoinflammatory syndrome. Autoinflammatory bone disorders are categorized to monogenic disorders such as pyogenic arthritis, pyoderma ;gangraenosum and acne (PAPA) syndrome, the deficiency of interleukine-1 receptor antagonist (DIRA) and Majeed syndrome and polygenic background or sporadic group such as chronic recurrent multifocal osteomyelitis (CRMO) or synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome are classified in sporadic group. Other autoinflammatory syndromes are rare causes of periodic fever in Iranian system registry. PMID:25562014

  3. 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

  4. The role of health informatics in clinical audit: part of the problem or key to the solution?

    Science.gov (United States)

    Georgiou, Andrew; Pearson, Michael

    2002-05-01

    The concepts of quality assurance (for which clinical audit is an essential part), evaluation and clinical governance each depend on the ability to derive and record measurements that describe clinical performance. Rapid IT developments have raised many new possibilities for managing health care. They have allowed for easier collection and processing of data in greater quantities. These developments have encouraged the growth of quality assurance as a key feature of health care delivery. In the past most of the emphasis has been on hospital information systems designed predominantly for the administration of patients and the management of financial performance. Large, hi-tech information system capacity does not guarantee quality information. The task of producing information that can be confidently used to monitor the quality of clinical care requires attention to key aspects of the design and operation of the audit. The Myocardial Infarction National Audit Project (MINAP) utilizes an IT-based system to collect and process data on large numbers of patients and make them readily available to contributing hospitals. The project shows that IT systems that employ rigorous health informatics methodologies can do much to improve the monitoring and provision of health care.

  5. Risk factors for clinical mastitis in a random sample of dairy herds from the southern part of The Netherlands.

    Science.gov (United States)

    Elbers, A R; Miltenburg, J D; De Lange, D; Crauwels, A P; Barkema, H W; Schukken, Y H

    1998-02-01

    The incidence of clinical mastitis in dairy cows was estimated in 171 randomly selected dairy herds from the southern part of The Netherlands. A total of 1103 quarter cases was reported. The mean annual incidence rate was 12.7 quarter cases/yr per 100 cows. The modeling incidence rate of clinical mastitis at the herd level indicated that a number of risk factors were associated with a higher rate of clinical mastitis: one or more cows that were leaking milk, one or more cows with trampled teats, no disinfection of the maternity area after calving, consistent use of post-milking teat disinfection, Red and White cattle (Meuse-Rhine-Yssel) as the predominant breed, and an annual bulk milk somatic cell count teats, no disinfection of the maternity area after calving, consistent use of post-milking teat disinfection, use of a thick layer of bedding in the stall, and the stripping of foremilk before cluster attachment. The following risk factors were associated with a higher rate of clinical mastitis caused by Staphylococcus aureus: Red and White cattle (Meuse-Rhine-Yssel) as the predominant breed, cows with trampled teats, the stripping of foremilk before cluster attachment, no regular disinfection of the stall, no regular replacement of stall bedding, and an annual bulk milk somatic cell count < 150,000 cells/ml.

  6. Current considerations concerning endodontically treated teeth: alteration of hard dental tissues and biomechanical properties following endodontic therapy.

    Science.gov (United States)

    Dimitriu, Bogdan; Vârlan, Constantin; Suciu, Ioana; Vârlan, Virginia; Bodnar, Dana

    2009-01-01

    The aim of this general article is to present an overview of the current knowledge about composition and structural changes and also about specific biomechanical alterations related to vitality loss or endodontic therapy. For a long time, these issues have been controversially approached from a clinical standpoint and are therefore still confusing for many practitioners. Vitality loss or endodontic procedures seem to induce only negligible changes in hard dental tissue moisture. Physico-chemical properties of dentin can be modified by some of the endodontic chemical products used for chemo-mechanical debridement. On the other hand, tooth biomechanical behavior is affected, since tooth strength is reduced proportionally to coronal tissue loss, due to either pre-existent carious/non-carious lesions or cavity acces preparation, besides restorative procedures. The related literature shows the lack of accepted clinical standards and consensus regarding the optimal way of approaching the specific tooth biomechanics following endodontic therapy.

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

    Science.gov (United States)

    Jensen, K; Gluud, C

    1994-10-01

    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 intermediate diameter that contain intermediate filament components (e.g., cytokeratins) observable by conventional light microscopy or immunohistochemical methods, identical in structure regardless of initiating factors or putative pathogenesis. Although three morphological types can be identified under 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, including estimates on the combined light microscopic and immunohistochemical prevalences and kinetics. Emphasis is placed on proper confounder control (in particular, alcohol history), which is highly essential but often inadequate. These conditions include (mean prevalence of Mallory bodies in parentheses): Indian childhood cirrhosis (73%), alcoholic hepatitis (65%), alcoholic cirrhosis (51%), Wilson's disease (25%), primary biliary cirrhosis (24%), nonalcoholic cirrhosis (24%), hepatocellular carcinoma (23%), morbid obesity (8%) and intestinal bypass surgery (6%). Studies in alcoholic hepatitis strongly suggest a hit-and-run effect of alcohol, whereas other chronic liver diseases show evidence of gradual increase in prevalence of Mallory bodies with severity of hepatic pathology. Mallory bodies in cirrhosis do not imply alcoholic pathogenesis. Obesity, however, is associated with alcoholism and diabetes, and Mallory bodies are only present in diabetic patients if alcoholism or obesity complicates the condition. In addition, case studies on diseases in which Mallory bodies

  8. Clinical pharmacokinetics of anxiolytics and hypnotics in the elderly. Therapeutic considerations (Part I).

    Science.gov (United States)

    Greenblatt, D J; Harmatz, J S; Shader, R I

    1991-09-01

    Anxiolytic and hypnotic drugs are extensively prescribed for elderly individuals throughout Western society. Old age may be associated with an altered clinical response to this class of compounds, and there is a considerable ethical and economic stake in understanding these changes so that therapy may be approached with a maximum likelihood of therapeutic benefit and a minimum risk of side effects. Old age may lead to altered pharmacokinetics of sedative-anxiolytic drugs, causing higher plasma concentrations (relative to young individuals) after single or multiple doses. By far the majority of the available scientific data refer to the benzodiazepines, which have become the most widely prescribed class of sedative-anxiolytic drugs. Although there is not complete consistency in the available data, the weight of evidence indicates that old age is associated with impaired clearance of the benzodiazepines which are biotransformed by microsomal oxidation (such as diazepam, desmethyldiazepam, desalkylflurazepam, bromazepam, alprazolam, triazolam and others). For those benzodiazepines metabolised mainly by glucuronide conjugation (oxazepam, lorazepam, temazepam) or nitroreduction (nitrazepam), there are minimal, if any, age-related decrements in clearance. Only in the case of triazolam is there direct evidence linking impaired clearance to enhanced clinical effects in the elderly. The logical suggestion that benzodiazepines biotransformed by conjugation or by nitroreduction may be safer for the elderly than those biotransformed by oxidation has not yet been directly validated. Reasonable epidemiological evidence has linked the use of long (versus short) half-life benzodiazepines (regardless of the specific metabolic pathway) with an increased incidence of adverse reactions such as confusion, falls and hip fractures in elderly persons. However, the decreased clearance and increased accumulation of the benzodiazepines in question are not clearly validated as the cause of

  9. [Contrast in static images in clinical magnetic resonance imaging. Part 2: Sequences for various contrast weightings and applications].

    Science.gov (United States)

    Schick, F

    2013-08-01

    The second part of this educational article focuses on sequence techniques in magnetic resonance imaging (MRI) and on suitable parameter sets for different contrast weightings. The content is based on the recently published part 1 of this educational article providing a survey on tissue properties relevant for most important contrast mechanisms. Characteristics of contrast weightings are presented in exemplary images recorded from healthy volunteers. Typical clinical applications of the most commonly used contrast weightings are described and discussed. Sequences for the following contrast weightings are included: proton density (density of hydrogen in small mobile molecules), relaxation times T1 and T2, chemical shift (water and fat), effects of magnetic susceptibility, restricted diffusion of water molecules and magnetization transfer between macromolecules and water molecules.

  10. 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.

  11. Current aspects of the clinic, diagnosis and treatment of acquired myasthenia gravis (review. Part 1: diagnostics

    Directory of Open Access Journals (Sweden)

    S. N. Bardakov

    2016-01-01

    Full Text Available Acquired myasthenia gravis is an autoimmune disease, based on the imbalance of humoral and cellular immunity, characterized by weakness and fatigue of skeletal muscles, and in some cases involvement of the heart muscle. In most cases, the object of the autoimmune destruction is peripheral nicotinic acetylcholine receptors of the postsynaptic membrane of the neuromuscular synapse. In myasthenia gravis there has been identified a number of other antigenic targets: muscle-specific tyrosine kinase, lowdensity lipoprotein receptor-related protein 4, titin, and ryanodine receptors skeletal muscles. Their specificity and pathogenetic role have been disclosed, but it is about 15-20% of seronegative forms that require further immunological research. Accurate diagnosis depends on the efficient detection of clinical forms of myasthenia gravis and full analysis of the autoimmune mechanisms underlying the disease.

  12. [Treatment with neutrons: hadrontherapy part II: physical basis and clinical experience].

    Science.gov (United States)

    Noël, G; Feuvret, L; Ferrand, R; Mazeron, J-J

    2003-10-01

    Neutrons have radiobiological characteristics, which differ from those of conventional radiotherapy beams (photons) and which offer a theoretical advantage over photons to fight radioresistance by the differential relative biological effect of them between normal and tumour tissues. Neutron therapy beneficed of great interest between 1975 and 1985. Many of phase III trials were conducted and indications have been definitively deducted of them. After briefly describing the properties of neutron beams, this review discusses the indication of neutron therapy on the basis of the clinical results. Salivary, prostate tumours and sarcomas are the main indications of neutron therapy. In concern to the prostate cancers, other alternative treatments reduce the neutron therapy field. For sarcomas, the lack of randomised trials limits the impact of the interest of neutrons. For other tumours, the ratio benefice/risk of neutron therapy is inferior to these obtained with photons and they could not be considered like classical indications.

  13. 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......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......, including estimates on the combined light microscopic and immunohistochemical prevalences and kinetics. Emphasis is placed on proper confounder control (in particular, alcohol history), which is highly essential but often inadequate. These conditions include (mean prevalence of Mallory bodies in parentheses...

  14. 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.

  15. 女性下肢力线旋转与髌股关节疼痛的临床研究%Clinical research of lower extremity biomechanical rotation and patellofemoral pain in women

    Institute of Scientific and Technical Information of China (English)

    凡廷旭; 黄伟; 胡宁; 陈诚

    2014-01-01

    Objective The purpose of this investigation was to discuss the relationship between the rotation of lower extremity biomechanics and patellofemoral pain(PFP) .Methods With normal volunteers as controls ,patients with PFP were scanned by ul‐trathin CT ,keeping the bilateral lower extremity straight neutral .The anatomy parameters were measured and analysed ,such as femoral neck anteversion(FNA) ,femoral neck shaft angle(NSA) ,posterior condylar angle(PCA) ,femoral rotation relative to tibia (FRRT) ,tibial torsion angle(TTA) and patella tilt angle(PTA) .Results Compared with control group ,the PFP group FNA ,FR‐RT ,PCA ,TTA and PTA increase statistically significant (P0 .05) .It could be found that PTA had the most obvious influence on the VAS score ,followed by FNA and TTA ;and PTA had the most obvious influence on the WOMAC function score ,followed by TTA ;and significant negative correlation could be found between PTA and age (r= -0 .548 ,P<0 .05) .Conclusion PTA is a sensitive indicator to assess VAS score and WOMAC function score for individ‐uals with PFPS .Increases of PTA ,FNA ,PCA ,FRRT and TTA are associated with PFP for women .%目的:探讨国人女性下肢力线旋转与髌股关节疼痛(PFP)的关系。方法以健康志愿者作对照组,对PFP患者行双下肢伸直中立位超薄CT扫描,分别对股骨前倾角(FNA)、颈干角(NSA)、后髁角(PCA)、股骨相对胫骨旋转角(FRRT)、胫骨扭转角(TTA)及髌骨倾斜角(PTA)进行测量、分析。结果PFP组与对照组FNA、FRRT、PCA、TTA及PTA比较均增大,差异有统计学意义(P<0.05),而NSA差异无统计学意义(P>0.05)。多元线性回归分析发现,PTA对视觉模拟评分法(VAS)评分影响最明显,其次是FNA,再次是TTA;PTA对骨性关节炎指数评分表(WOMAC)功能评分影响最明显,其次是TTA。PTA与年龄存在显著负相关(r=-0.548,P<0.05)。结论PTA是衡

  16. Diabetes and vascular disease: pathophysiology, clinical consequences, and medical therapy: part I.

    Science.gov (United States)

    Paneni, Francesco; Beckman, Joshua A; Creager, Mark A; Cosentino, Francesco

    2013-08-01

    Hyperglycemia and insulin resistance are key players in the development of atherosclerosis and its complications. A large body of evidence suggest that metabolic abnormalities cause overproduction of reactive oxygen species (ROS). In turn, ROS, via endothelial dysfunction and inflammation, play a major role in precipitating diabetic vascular disease. A better understanding of ROS-generating pathways may provide the basis to develop novel therapeutic strategies against vascular complications in this setting. Part I of this review will focus on the most current advances in the pathophysiological mechanisms of vascular disease: (i) emerging role of endothelium in obesity-induced insulin resistance; (ii) hyperglycemia-dependent microRNAs deregulation and impairment of vascular repair capacities; (iii) alterations of coagulation, platelet reactivity, and microparticle release; (iv) epigenetic-driven transcription of ROS-generating and proinflammatory genes. Taken together these novel insights point to the development of mechanism-based therapeutic strategies as a promising option to prevent cardiovascular complications in diabetes.

  17. The Objective Structured Clinical Examination (OSCE): AMEE Guide No. 81. Part II: organisation & administration.

    Science.gov (United States)

    Khan, Kamran Z; Gaunt, Kathryn; Ramachandran, Sankaranarayanan; Pushkar, Piyush

    2013-09-01

    The organisation, administration and running of a successful OSCE programme need considerable knowledge, experience and planning. Different teams looking after various aspects of OSCE need to work collaboratively for an effective question bank development, examiner training and standardised patients' training. Quality assurance is an ongoing process taking place throughout the OSCE cycle. In order for the OSCE to generate reliable results it is essential to pay attention to each and every element of quality assurance, as poorly standardised patients, untrained examiners, poor quality questions and inappropriate scoring rubrics each will affect the reliability of the OSCE. The validity will also be influenced if the questions are not realistic and mapped against the learning outcomes of the teaching programme. This part of the Guide addresses all these important issues in order to help the reader setup and quality assure their new or existing OSCE programmes.

  18. 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

    2014-01-01

    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

  19. 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

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

    Science.gov (United States)

    Gonzalez, Albin; Bauer, Lisa; Kinney, Vicki; Crooks, Cheryl

    2008-03-01

    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

  1. Fad diets and obesity--Part I: Measuring weight in a clinical setting.

    Science.gov (United States)

    Moyad, Mark A

    2004-04-01

    Obesity is a recognized epidemic in many regions around the world and billions of dollars are spent each year in attempting to combat this problem. However, before a discussion of the different conventional and alternative treatments for obesity can be initiated, it is first critical to determine whether or not a certain individual is actually overweight, obese, or has an excess of adipose tissue. Therefore, a review of the various popular and unpopular measurements of obesity is needed. A variety of measurements exist such as bioelectrical impedance, body mass index (BMI), crude weight, densitometry, dual energy x-ray absorptiometry (DEXA), lean body mass (LBM), skinfold thickness, and waist-to-hip ratio (WHR). All of these measurements contain inherent advantages and disadvantages, but many of these can still be used in a clinical setting. Health professionals should acquaint themselves with these different measurements in order to take the first step in bringing attention to and potentially treating a condition that affects virtually every medical discipline.

  2. [Ultrasound spatial clinical analysis of the orbital part of the lacrimal gland in health].

    Science.gov (United States)

    Avetisov, S E; Kharlap, S I; Markosian, A G; Safonova, T N; Likhvantseva, V G; Nasnikova, I Iu

    2006-01-01

    The paper presents an algorithm of ultrasound spatial analysis of the unaltered lacrimal gland. The algorithm has been used to define its shape, size, density, structural features and the pattern of blood supply, as well as the anatomic and topographic position in the orbit. The study was conducted in the B- and 3D-modes of color and energy Doppler mapping on both sides. The procedure was based on the clinical examination of 40 healthy individuals aged 20 to 75 years who had no systemic vascular and lymphoid tissue lesions or functional impairments of the lacrimal gland itself. The study defined the mean values of the ultrasound section of the lacrimal gland: 1-1.8 and 0.5-0.8 cm for vertical and horizontal ones, respectively; the mean volume of the lacrimal gland of 0.66 to 1 cm(3) and the densitometric parameters (density and vasculogenicity index); three types of structural manifestations of the unaltered lacrimal gland were identified. The proposed algorithm of ultrasound study of the lacrimal gland may enhance the accuracy and validity of results in the differential diagnosis of various orbital diseases.

  3. 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

  4. Characterization of levofloxacin non-susceptible clinical Streptococcus pyogenes isolated in the central part of Italy.

    Science.gov (United States)

    Petrelli, D; Di Luca, M C; Prenna, M; Bernaschi, P; Repetto, A; Vitali, L A

    2014-02-01

    We investigated the prevalence, genetics, and clonality of fluoroquinolone non-susceptible isolates of Streptococcus pyogenes in the central part of Italy. S. pyogenes strains (n = 197) were isolated during 2012 from patients with tonsillopharyngitis, skin, wound or invasive infections and screened for fluoroquinolone non-susceptibility (resistance to norfloxacin and levofloxacin minimum inhibitory concentration (MIC) = 2 mg/L) following EUCAST guidelines. First-step topoisomerase parC and gyrA substitutions were investigated using sequencing analysis. Clonality was determined by pulsed field gel electrophoresis (PFGE; SmaI digestion) and by emm typing. The fluoroquinolone non-susceptible phenotype was identified in 18 isolates (9.1 %) and correlated with mutations in parC, but not in gyrA, the most frequent leading to substitution of the serine at position 79 with an alanine. Most of the fluoroquinolone non-susceptible isolates belonged to the emm-type 6, even if other emm-types were also represented (emm75, emm89, and emm2). A significant level of association was measured between PFGE and both emm type and substitutions in parC. The prevalence of fluoroquinolone non-susceptible Streptococcus pyogenes isolates in Italy is of concern and, although the well-known emm type 6 is dominant, other types are appearing and spreading.

  5. Technique of the biomechanical analysis of execution of upward jump piked

    Directory of Open Access Journals (Sweden)

    Nataliya Batieieva

    2016-12-01

    Full Text Available Purpose: the biomechanical analysis of execution of upward jump piked. Material & Methods: the following methods of the research were used: theoretical analysis and synthesis of data of special scientific and methodical literature; photographing, video filming, biomechanical computer analysis, pedagogical observation. Students (n=8 of the chair of national choreography of the department of choreographic art of Kiev national university of culture and art took part in carrying out the biomechanical analysis of execution of upward jump piked. Results: the biomechanical analysis of execution of upward jump piked is carried out, the kinematic characteristics (way, speed, acceleration, effort of the general center of weight (GCW and center of weight (CW of biolinks of body of the executor are received (feet, shins, hips, shoulder, forearm, hands. Biokinematic models (phases are constructed. Power characteristics are defined – mechanical work and kinetic energy of links of legs and hands at execution of upward jump piked. Conclusions: it is established that the technique of execution of upward jump piked considerably influences the level of technical training of the qualified sportsmen in gymnastics (sports, in aerobic gymnastics (aerobics, diving and dancing sports.

  6. Tardive Dyskinesia Revisited-A Clinical Management Priority Perspective: A Voyage into High Dose Buspirone Part B

    Directory of Open Access Journals (Sweden)

    Vernon M Neppe

    2016-06-01

    Full Text Available We discuss several major related and integrated issues in this two-part series of papers on tardive dyskinesia (TD. In this, the second paper, Part B, the management and mechanisms are emphasized; in Part A the diagnosis and assessment of tardive dyskinesia was discussed. In this Part B series of articles we examine several special important priorities in this condition associated with sometimes permanent involuntary abnormal movements associated with the neuroleptic drugs. We particularly examine the management of this enormously important condition. After the diagnosis and assessment of TD, comes the clinical approach to management and the options and theories behind that approach. There remain no approved medications for the management of tardive dyskinesia. Therefore, all treatments are “out of labeling”. The purpose of this paper is to shed light on high dose buspirone treatment, originally described by the author in 1989 [1], and which after more than a quarter century requires re-evaluation as it still appears, in the author’s opinion, to be the logical and most appropriate management for TD. A major issue focuses, on the updated experience of more than a quarter century with generally almost completely positive effects of high-dose buspirone (HDB treatment of tardive dyskinesia (TD and the next issue provides an important, major theoretical demonstration of the mechanism of tardive dyskinesia. The dopamine 2 or 2-3 supersensitivity hypothesis as a cause of TD is strongly supported by HDB. In Part B, the issue of choice of medication for psychosis and related medical conditions becomes pertinent. The choices relate to the newer second generation atypical neuroleptics (SGAs compared with the older typical, first generation neuroleptics (FGAs. The generally more expensive SGA drugs have become far the most used anti-psychotic agents in wealthy countries such as the United States, because of their efficacy and ostensible safety

  7. Extracellular volume fraction mapping in the myocardium, part 2: initial clinical experience

    Directory of Open Access Journals (Sweden)

    Kellman Peter

    2012-09-01

    Full Text Available Abstract Background Diffuse myocardial fibrosis, and to a lesser extent global myocardial edema, are important processes in heart disease which are difficult to assess or quantify with cardiovascular magnetic resonance (CMR using conventional late gadolinium enhancement (LGE or T1-mapping. Measurement of the myocardial extracellular volume fraction (ECV circumvents factors that confound T1-weighted images or T1-maps. We hypothesized that quantitative assessment of myocardial ECV would be clinically useful for detecting both focal and diffuse myocardial abnormalities in a variety of common and uncommon heart diseases. Methods A total of 156 subjects were imaged including 62 with normal findings, 33 patients with chronic myocardial infarction (MI, 33 with hypertrophic cardiomyopathy (HCM, 15 with non-ischemic dilated cardiomyopathy (DCM, 7 with acute myocarditis, 4 with cardiac amyloidosis, and 2 with systemic capillary leak syndrome (SCLS. Motion corrected ECV maps were generated automatically from T1-maps acquired pre- and post-contrast calibrated by blood hematocrit. Abnormally-elevated ECV was defined as >2SD from the mean ECV in individuals with normal findings. In HCM the size of regions of LGE was quantified as the region >2 SD from remote. Results Mean ECV of 62 normal individuals was 25.4 ± 2.5% (m ± SD, normal range 20.4%-30.4%. Mean ECV within the core of chronic myocardial infarctions (without MVO (N = 33 measured 68.5 ± 8.6% (p  Conclusions ECV mapping appears promising to complement LGE imaging in cases of more homogenously diffuse disease. The ability to display ECV maps in units that are physiologically intuitive and may be interpreted on an absolute scale offers the potential for detection of diffuse disease and measurement of the extent and severity of abnormal regions.

  8. [Expert evidence in whiplash injury: interdisciplinary orthopaedic and biomechanical approach].

    Science.gov (United States)

    Magin, M N; Auer, C

    2014-03-01

    Considering the controversially discussed issue of whiplash injury a pragmatic approach based on our own experience in the area of forensic expert opinion is presented. Findings of accident analysis and biomechanics are correlated with the individual situation after the accident (initial clinical appearance), the course of the ailment and the indispensable physical examination. The latter leads to determination of the individual vulnerability (not increased/increased) which is important for the evaluation of the physical condition and estimation of the physical stress limit. These limits vary widely between individuals and must be considered carefully when relating dose and effect of accident severity to a possible physical injury. Determination of the accident severity is especially important when there are no objective signs of injury and the existence of a minor whiplash injury (Quebec Task Force degree 1 or 2) is in question.

  9. The anatomy and biomechanics of acute and chronic whiplash injury.

    Science.gov (United States)

    Siegmund, Gunter P; Winkelstein, Beth A; Ivancic, Paul C; Svensson, Mats Y; Vasavada, Anita

    2009-04-01

    Whiplash injury is the most common motor vehicle injury, yet it is also one of the most poorly understood. Here we examine the evidence supporting an organic basis for acute and chronic whiplash injuries and review the anatomical sites within the neck that are potentially injured during these collisions. For each proposed anatomical site--facet joints, spinal ligaments, intervertebral discs, vertebral arteries, dorsal root ganglia, and neck muscles--we present the clinical evidence supporting that injury site, its relevant anatomy, the mechanism of and tolerance to injury, and the future research needed to determine whether that site is responsible for some whiplash injuries. This article serves as a snapshot of the current state of whiplash biomechanics research and provides a roadmap for future research to better understand and ultimately prevent whiplash injuries.

  10. Advancements in identifying biomechanical determinants for abdominal aortic aneurysm rupture.

    Science.gov (United States)

    Kontopodis, Nikolaos; Metaxa, Eleni; Papaharilaou, Yannis; Tavlas, Emmanouil; Tsetis, Dimitrios; Ioannou, Christos

    2015-02-01

    Abdominal aortic aneurysms are a common health problem and currently the need for surgical intervention is determined based on maximum diameter and growth rate criteria. Since these universal variables often fail to predict accurately every abdominal aortic aneurysms evolution, there is a considerable effort in the literature for other markers to be identified towards individualized rupture risk estimations and growth rate predictions. To this effort, biomechanical tools have been extensively used since abdominal aortic aneurysm rupture is in fact a material failure of the diseased arterial wall to compensate the stress acting on it. The peak wall stress, the role of the unique geometry of every individual abdominal aortic aneurysm as well as the mechanical properties and the local strength of the degenerated aneurysmal wall, all confer to rupture risk. In this review article, the assessment of these variables through mechanical testing, advanced imaging and computational modeling is reviewed and the clinical perspective is discussed.

  11. The psychopharmacology of aggressive behavior: a translational approach: part 2: clinical studies using atypical antipsychotics, anticonvulsants, and lithium.

    Science.gov (United States)

    Comai, Stefano; Tau, Michael; Pavlovic, Zoran; Gobbi, Gabriella

    2012-04-01

    Patients experiencing mental disorders are at an elevated risk for developing aggressive behavior. In the past 10 years, the psychopharmacological treatment of aggression has changed dramatically owing to the introduction of atypical antipsychotics on the market and the increased use of anticonvulsants and lithium in the treatment of aggressive patients.This review (second of 2 parts) uses a translational medicine approach to examine the neurobiology of aggression, discussing the major neurotransmitter systems implicated in its pathogenesis (serotonin, glutamate, norepinephrine, dopamine, and γ-aminobutyric acid) and the neuropharmacological rationale for using atypical antipsychotics, anticonvulsants, and lithium in the therapeutics of aggressive behavior. A critical review of all clinical trials using atypical antipsychotics (aripiprazole, clozapine, loxapine, olanzapine, quetiapine, risperidone, ziprasidone, and amisulpride), anticonvulsants (topiramate, valproate, lamotrigine, and gabapentin), and lithium are presented. Given the complex, multifaceted nature of aggression, a multifunctional combined therapy, targeting different receptors, seems to be the best strategy for treating aggressive behavior. This therapeutic strategy is supported by translational studies and a few human studies, even if additional randomized, double-blind, clinical trials are needed to confirm the clinical efficacy of this framework.

  12. 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.)

  13. Discrimination of biomechanically possible and impossible hand movements at birth.

    Science.gov (United States)

    Longhi, Elena; Senna, Irene; Bolognini, Nadia; Bulf, Hermann; Tagliabue, Paolo; Cassia, Viola Macchi; Turati, Chiara

    2015-01-01

    The development of human body perception has long been investigated, but little is known about its early origins. This study focused on how a body part highly relevant to the human species, namely the hand, is perceived a few days after birth. Using a preferential-looking paradigm, 24- to 48-hr-old newborns watched biomechanically possible and impossible dynamic hand gestures (Experiment 1, N = 15) and static hand postures (Experiment 2, N = 15). In Experiment 1, newborns looked longer at the impossible, compared to the possible, hand movement, whereas in Experiment 2 no visual preference emerged. These findings suggest that early in life the representation of the human body may be shaped by sensory-motor experience.

  14. Biomechanical remodeling of the chronically obstructed Guinea pig small intestine.

    Science.gov (United States)

    Storkholm, Jan Henrik; Zhao, Jingbo; Villadsen, Gerda E; Hager, H; Jensen, Steen L; Gregersen, Hans

    2007-02-01

    Small intestinal obstruction is a frequently encountered clinical problem. To understand the mechanisms behind obstruction and the clinical consequences, data are needed on the relation between the morphologic and biomechanical remodeling that takes place in the intestinal wall during chronic obstruction. We sought to determine the effect of partial obstruction on mechanical and morphologic properties of the guinea pig small intestine. Partial obstruction was created surgically in 2 groups of animals living for 2 and 4 weeks. Controls were sham operated and lived for 4 weeks. A combined impedance planimetry-high-frequency ultrasound system was designed to measure the luminal cross-sectional area and wall thickness. These measures were used to compute the circumferential stress and strain of the excised intestinal segments. The incremental elastic modulus was obtained by using nonlinear fitting of the stress-strain curve. Histologic analysis and the measurements of total wall collagen were also performed. The luminal cross-sectional area, wall thickness, and elastic modulus in circumferential direction increased in a time-dependent manner proximal to the obstruction site (P 0.25). The circumferential stress-strain curves of the proximal segments in 2- and 4-week groups shifted to the left, indicating the intestinal wall became stiffer. Histologic examination revealed a massive increase in the thickness of the muscle layer especially the circular smooth muscle layer (P < 0.05). The collagen content proximal to the obstruction site was significantly larger in the partially obstructed animals compared to controls (P < 0.05). No difference was found distal to the obstruction site. Strong correlation was found between the collagen content and the elastic modulus at stress levels of 70 kPa stress (P < 0.01) and 10 kPa (P < 0.05) proximal to the obstruction site suggesting that the alteration of collagen has great impact on the mechanical remodeling. The morphologic and

  15. Supplementing biomechanical modeling with EMG analysis

    Science.gov (United States)

    Lewandowski, Beth; Jagodnik, Kathleen; Crentsil, Lawton; Humphreys, Bradley; Funk, Justin; Gallo, Christopher; Thompson, William; DeWitt, John; Perusek, Gail

    2016-01-01

    It is well established that astronauts experience musculoskeletal deconditioning when exposed to microgravity environments for long periods of time. Spaceflight exercise is used to counteract these effects, and the Advanced Resistive Exercise Device (ARED) on the International Space Station (ISS) has been effective in minimizing musculoskeletal losses. However, the exercise devices of the new exploration vehicles will have requirements of limited mass, power and volume. Because of these limitations, there is a concern that the exercise devices will not be as effective as ARED in maintaining astronaut performance. Therefore, biomechanical modeling is being performed to provide insight on whether the small Multi-Purpose Crew Vehicle (MPCV) device, which utilizes a single-strap design, will provide sufficient physiological loading to maintain musculoskeletal performance. Electromyography (EMG) data are used to supplement the biomechanical model results and to explore differences in muscle activation patterns during exercises using different loading configurations.

  16. 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.

  17. The anatomy and biomechanics of running.

    Science.gov (United States)

    Nicola, Terry L; Jewison, David J

    2012-04-01

    To understand the normal series of biomechanical events of running, a comparative assessment to walking is helpful. Closed kinetic chain through the lower extremities, control of the lumbopelvic mechanism, and overall symmetry of movement has been described well enough that deviations from normal movement can now be associated with specific overuse injuries experienced by runners. This information in combination with a history of the runner's errors in their training program will lead to a more comprehensive treatment and prevention plan for related injuries.

  18. Development of a biomechanical energy harvester

    OpenAIRE

    Donelan J Maxwell; Naing Veronica; Li Qingguo

    2009-01-01

    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 em...

  19. Biomechanics of pediatric manual wheelchair mobility

    Directory of Open Access Journals (Sweden)

    Brooke A. Slavens

    2015-09-01

    Full Text Available Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting and stopping tasks. A Vicon motion analysis system captured movement, while a SmartWheel simultaneously collected three-dimensional forces and moments occurring at the hand-rim. A custom pediatric inverse dynamics model was used to evaluate three-dimensional upper extremity joint motions, forces and moments of 14 children with spinal cord injury (SCI during the functional tasks. Additionally, pain and health-related quality of life outcomes were assessed. This research found that joint demands are significantly different amongst functional tasks, with greatest demands placed on the shoulder during the starting task. Propulsion was significantly different from starting and stopping at all joints. We identified multiple stroke patterns used by the children, some of which are not standard in adults. One subject reported average daily pain, which was minimal. Lower than normal physical health and higher than normal mental health was found in this population. It can be concluded that functional tasks should be considered in addition to propulsion for rehabilitation and SCI treatment planning. This research provides wheelchair users and clinicians with a comprehensive, biomechanical, mobility assessment approach for wheelchair prescription, training, and long-term care of children with SCI.

  20. Ergonomic Evaluation of Biomechanical Hand Function

    OpenAIRE

    Lee, Kyung-Sun; Jung, Myung-Chul

    2014-01-01

    The human hand is a complex structure that performs various functions for activities of daily living and occupations. This paper presents a literature review on the methodologies used to evaluate hand functions from a biomechanics standpoint, including anthropometry, kinematics, kinetics, and electromyography (EMG). Anthropometry describes the dimensions and measurements of the hand. Kinematics includes hand movements and the range of motion of finger joints. Kinetics includes hand models for...

  1. A Biomechanical Modeling Guided CBCT Estimation Technique.

    Science.gov (United States)

    Zhang, You; Tehrani, Joubin Nasehi; Wang, Jing

    2017-02-01

    Two-dimensional-to-three-dimensional (2D-3D) deformation has emerged as a new technique to estimate cone-beam computed tomography (CBCT) images. The technique is based on deforming a prior high-quality 3D CT/CBCT image to form a new CBCT image, guided by limited-view 2D projections. The accuracy of this intensity-based technique, however, is often limited in low-contrast image regions with subtle intensity differences. The solved deformation vector fields (DVFs) can also be biomechanically unrealistic. To address these problems, we have developed a biomechanical modeling guided CBCT estimation technique (Bio-CBCT-est) by combining 2D-3D deformation with finite element analysis (FEA)-based biomechanical modeling of anatomical structures. Specifically, Bio-CBCT-est first extracts the 2D-3D deformation-generated displacement vectors at the high-contrast anatomical structure boundaries. The extracted surface deformation fields are subsequently used as the boundary conditions to drive structure-based FEA to correct and fine-tune the overall deformation fields, especially those at low-contrast regions within the structure. The resulting FEA-corrected deformation fields are then fed back into 2D-3D deformation to form an iterative loop, combining the benefits of intensity-based deformation and biomechanical modeling for CBCT estimation. Using eleven lung cancer patient cases, the accuracy of the Bio-CBCT-est technique has been compared to that of the 2D-3D deformation technique and the traditional CBCT reconstruction techniques. The accuracy was evaluated in the image domain, and also in the DVF domain through clinician-tracked lung landmarks.

  2. 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...

  3. The Corneoscleral Shell of the Eye: an Age-Related Analysis of Structural Biomechanical Properties. Literature review

    Directory of Open Access Journals (Sweden)

    E. N. Iomdina

    2016-01-01

    Full Text Available Structural biomechanical properties of the ocular corneoscleral shell largely determine its anatomic and optical parameters and its supporting and protective function. Therefore, changes related to age restructuring processes may affect the state of the cornea and the sclera, which should be taken into account in diagnosing eye diseases, especially age-related. According to actual literary data, age-related changes of the corneoscleral shell affecting its biomechanical properties involve all connective tissue components of the extracellular matrix: fibrous proteins (collagen and elastin and intermediate substance components (proteoglycans and glycosaminoglycans. Aged patients have a larger diameter of elastic fiber fibrils in the external part of the sclera and a lower density of fibrils in the center as compared to young patients, which is an evidence of elastin damage at the molecular level and fibril degeneration. Age-related changes of proteoglycans are primarilymanifested in hydration loss, which leads to an increase in corneal and sclera density and regional thinning of tissues. Agerelated changes of collagen are less expressed than those of elastin and proteoglycans. Yet, the distance between collagen fibrils in the cornea becomes smaller with age; they are subject to destruction, and small spaces devoid of collagen tend to appear in the posterior stroma. The most pronounced age-related degenerative changes of collagen in the deeper layers of the corneal stroma occur in the limb, which accumulates more cross striated collagen fibrils. Recent years of research have shown that the formation of cross-linked chemical bonds, i.e. intra- and intermolecular cross links of collagen is the most important structural factor. It is this particular process that is responsible for structural stability of the corneal and scleral tissue, which tends to change with age or due to certain eye diseases, such as keratoconus or progressive myopia

  4. Redefining lumbosacral transitional vertebrae (LSTV) classification: integrating the full spectrum of morphological alterations in a biomechanical continuum.

    Science.gov (United States)

    Mahato, Niladri Kumar

    2013-07-01

    In light of advancements in imaging techniques and basic science studies, this study proposes modifications in the existing Castellvi's classification for better clinical and biomechanical correlation of LSTV subtypes. LSTVs are commonly occurring variations of the lower spine. The current system does not include functionally important structural variations of the neural arch components and sacral auricular surfaces induced by LSTV afflictions within the classification. This study is an attempt to integrate vital biomechanical correlates into the proposed modification. Emerging diagnostic and clinical evidence also point out the need of understating subdivisions within LSTV anomalies as distinctly stratified entities to get a better correlation with the biomechanical continuum involved with LSTV associated low back pain. Important neural arch element and sacral auricular surface alterations associated with each LSTV subtypes were studied from a large number of osseous samples and data available from published LSTV related clinical and morphological studies. Sacralisation and lumbarisation were designated separate stratifications in the proposed revision, with arrangement of the LSTV subtypes as members of a LSTV anatomical 'array' extending cranio-caudally at the lumbo-sacral junction. The proposed modification is capable of identifying LSTV associated structural defects (in anterior and posterior elements), their exact level of occurrence and status of facet and auricular surface morphologies. Coding for the inclusion of biomechanically important alterations associated with LSTV types within the proposed new classification would probably be helpful in better clinical correlation of LSTV.

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. An Evidence-Based Videotaped Running Biomechanics Analysis.

    Science.gov (United States)

    Souza, Richard B

    2016-02-01

    Running biomechanics play an important role in the development of injuries. Performing a running biomechanics analysis on injured runners can help to develop treatment strategies. This article provides a framework for a systematic video-based running biomechanics analysis plan based on the current evidence on running injuries, using 2-dimensional (2D) video and readily available tools. Fourteen measurements are proposed in this analysis plan from lateral and posterior video. Identifying simple 2D surrogates for 3D biomechanic variables of interest allows for widespread translation of best practices, and have the best opportunity to impact the highly prevalent problem of the injured runner.

  10. Biomechanics of subcellular structures by non-invasive Brillouin microscopy

    Science.gov (United States)

    Antonacci, Giuseppe; Braakman, Sietse

    2016-11-01

    Cellular biomechanics play a pivotal role in the pathophysiology of several diseases. Unfortunately, current methods to measure biomechanical properties are invasive and mostly limited to the surface of a cell. As a result, the mechanical behaviour of subcellular structures and organelles remains poorly characterised. Here, we show three-dimensional biomechanical images of single cells obtained with non-invasive, non-destructive Brillouin microscopy with an unprecedented spatial resolution. Our results quantify the longitudinal elastic modulus of subcellular structures. In particular, we found the nucleoli to be stiffer than both the nuclear envelope (p biomechanics and its role in pathophysiology.

  11. 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

  12. 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

  13. 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.

  14. Application of techniques of biomechanics in the status evaluation and pathology correction of locomotor system

    Directory of Open Access Journals (Sweden)

    Romakina N.A.

    2015-09-01

    Full Text Available The article deals with the problem of development and the modern state of biomechanics as a scientific and practical direction in medicine under the context of technological advance herein a specific attention is paid to the achievements of the Russian schools. It is shown a necessity of wide usage of instrumental biomechanical diagnostics of locomotive disorders for intrinsic substantiation of rehabilitation treatment tactics and monitoring of its medical efficiency particularly for persons with remote effects of surgical interventions such as osteosynthesis, spondylosynthesis, total joint replacements. Non-invasive technique, possibility of its multiple application and rather low cost make actual using of locomotion clinical analysis techniques for rehabilitation treatment of concerned patients of different age groups.

  15. Evaluating the biomechanics of the pediatric foot in Turner syndrome: a case report.

    Science.gov (United States)

    Morrison, Stewart C; Izod, Alexander; Mahaffey, Ryan

    2012-01-01

    Turner syndrome is a genetic disorder that can present clinically with multiple concurrent comorbidities. This case report describes a 12-year-old girl with Turner syndrome who was referred for podiatric medical assessment and explores the application of optoelectronic stereophotogrammetry in the biomechanical assessment of the foot and lower limb. A four-segment kinematic foot model using 14-mm reflective markers was applied to the foot and lower limb of the patient to track motion at the tibia, rearfoot, forefoot, and hallux. Kinematic results presented in this case study illustrate evidence of excessive foot pronation throughout the stance phase of gait. Whether excessive pronation is a general characteristic of foot function in Turner syndrome remains to be confirmed, but the findings presented suggest that a comprehensive evaluation of foot biomechanics in patients with Turner syndrome may be warranted.

  16. 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.

  17. 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.

  18. 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

  19. Aortic biomechanics in hypertrophic cardiomyopathy

    Science.gov (United States)

    Badran, Hala Mahfouz; Soltan, Ghada; Faheem, Nagla; Elnoamany, Mohamed Fahmy; Tawfik, Mohamed; Yacoub, Magdi

    2015-01-01

    phenotype, not LV deformation, is interrelated to aortic stiffness in patients with HCM. The increased aortic stiffness seems to be promising module that can be added as clinical risk parameter in HCM. PMID:26566526

  20. 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…

  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. 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…

  3. 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...

  4. BIOMECHANICS AND PATHOMECHANICS OF THE PATELLOFEMORAL JOINT.

    Science.gov (United States)

    Loudon, Janice K

    2016-12-01

    The patellofemoral joint is a joint that can be an area of concern for athletes of various sports and ages. The joint is somewhat complex with multiple contact points and numerous tissues that attach to the patella. Joint forces are variable and depend on the degree of knee flexion and whether the foot is in contact with the ground. The sports medicine specialist must have a good working knowledge of the anatomy and biomechanics of the patellofemoral joint in order to treat it effectively.

  5. 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...

  6. Optic nerve head biomechanics in aging and disease.

    Science.gov (United States)

    Downs, J Crawford

    2015-04-01

    This nontechnical review is focused upon educating the reader on optic nerve head biomechanics in both aging and disease along two main themes: what is known about how mechanical forces and the resulting deformations are distributed in the posterior pole and ONH (biomechanics) and what is known about how the living system responds to those deformations (mechanobiology). We focus on how ONH responds to IOP elevations as a structural system, insofar as the acute mechanical response of the lamina cribrosa is confounded with the responses of the peripapillary sclera, prelaminar neural tissues, and retrolaminar optic nerve. We discuss the biomechanical basis for IOP-driven changes in connective tissues, blood flow, and cellular responses. We use glaucoma as the primary framework to present the important aspects of ONH biomechanics in aging and disease, as ONH biomechanics, aging, and the posterior pole extracellular matrix (ECM) are thought to be centrally involved in glaucoma susceptibility, onset and progression.

  7. Biomechanical and clinical researches of cervical spine locking plate for treatment of cervical bursting fracture%颈椎前路带锁钢板治疗颈椎爆裂骨折的试验及临床研究

    Institute of Scientific and Technical Information of China (English)

    陈福文; 周密; 贾连顺; 张树明; 王剑平; 宋迪煜; 朱方正; 朱泽兴

    2012-01-01

    Objective To evaluate the stability and clinical feasibility of cervical spine locking plate (CSLP)for the treatment of cervical fractures. Methods Six fresh cadaver cervical specimens (from C2-6) were used for test. The normal three -dimension motions of C3_5 segments were measured on a three-dimensional spinal motion test machine. Then C4 bursting fracture models were built to measure the range of motions (ROM). Iliac bony grafts were implanted and the ROM were tested once more. Finally the injured segments were fixed with AO cervical spine locking plate to measure the ROM. Thirty-two cases of lower cervical spine fractures were treated surgically with anterior decompression and fusion, and were internally fixed with CSLP. Results After bony implantation and CSLP fixation, the ROM of cervical spines in flexion/extension, left/right bending, and left/right axial rotation reduced significantly. Compared with normal ROM, flexion/extension and left/right bending were reduced significantly while left/right axial rotation didn't change significantly. After 6-48 months follow-up, all fracture were reduced completely and implanted bone was fused. Postoperative X-ray showed plates and screws were in their correct position, no loosening and breakage of both plates and screws was found. Conclusion CSLP is an ideal fixation apparatus for treatment of cervical fracture in cervical spine and can restore stability in three-dimensional ROM.%目的 评价颈椎前路带锁钢板固定系统(CSLP)治疗颈椎骨折的稳定性及临床有效性.方法 将6具新鲜成人颈椎标本(C2~6)置于脊柱三维测量仪上测定C3~5节段的ROM,制造C4爆裂骨折,测定其三维运动变化后分别进行植骨、植骨+CSLP固定,并重复测量其三维运动.对32例下颈椎骨折行前路减压融合,并以CSLP进行内固定治疗.结果 植骨+CSLP固定后在屈伸、侧弯、旋转方向较损伤后明显下降,与正常值相比,屈伸和侧弯运动均明显减少,但

  8. Energy storage and release of prosthetic feet Part 2: Subjective ratings of 2 energy storing and 2 conventional feet, user choice of foot and deciding factor

    NARCIS (Netherlands)

    Postema, K.; Hermens, H.J.; Vries, de J.; Koopman, H.F.J.M.; Eisma, W.H.

    1997-01-01

    This paper is the second part of a study on biomechanical and functional properties of prosthetic feet. The first part dealt with a biomechanical analysis related to user benefits. This part deals with subjective ratings and deciding factors for trans-tibial amputees using 2 energy storing feet (ESF

  9. C2-fractures: part II. A morphometrical analysis of computerized atlantoaxial motion, anatomical alignment and related clinical outcomes.

    Science.gov (United States)

    Koller, Heiko; Acosta, Frank; Forstner, Rosemarie; Zenner, Juliane; Resch, Herbert; Tauber, Mark; Lederer, Stefan; Auffarth, Alexander; Hitzl, Wolfgang

    2009-08-01

    Knowledge on the outcome of C2-fractures is founded on heterogenous samples with cross-sectional outcome assessment focusing on union rates, complications and technical concerns related to surgical treatment. Reproducible clinical and functional outcome assessments are scant. Validated generic and disease specific outcome measures were rarely applied. Therefore, the aim of the current study is to investigate the radiographic, functional and clinical outcome of a patient sample with C2-fractures. Out of a consecutive series of 121 patients with C2 fractures, 44 met strict inclusion criteria and 35 patients with C2-fractures treated either nonsurgically or surgically with motion-preserving techniques were surveyed. Outcome analysis included validated measures (SF-36, NPDI, CSOQ), and a functional CT-scanning protocol for the evaluation of C1-2 rotation and alignment. Mean follow-up was 64 months and mean age of patients was 52 years. Classification of C2-fractures at injury was performed using a detailed morphological description: 24 patients had odontoid fractures type II or III, 18 patients had fracture patterns involving the vertebral body and 11 included a dislocated or a burst lateral mass fracture. Thirty-one percent of patients were treated with a halo, 34% with a Philadelphia collar and 34% had anterior odontoid screw fixation. At follow-up mean atlantoaxial rotation in left and right head position was 20.2 degrees and 20.6 degrees, respectively. According to the classification system of posttreatment C2-alignment established by our group in part I of the C2-fracture study project, mean malunion score was 2.8 points. In 49% of patients the fractures healed in anatomical shape or with mild malalignment. In 51% fractures healed with moderate or severe malalignment. Self-rated outcome was excellent or good in 65% of patients and moderate or poor in 35%. The raw data of varying nuances allow for comparison in future benchmark studies and metaanalysis. Detailed

  10. [The biomechanics of hyperextension injuries of the subaxial cervical spine].

    Science.gov (United States)

    Stein, G; Meyer, C; Ingenhoff, L; Bredow, J; Müller, L P; Eysel, P; Schiffer, G

    2016-05-24

    Hyperextension injuries of the subaxial cervical spine are potentially hazardous due to relevant destabilization. Depending on the clinical condition, neurologic or vascular damage may occur. Therefore an exact knowledge of the factors leading to destabilization is essential. In a biomechanical investigation, 10 fresh human cadaver cervical spine specimens were tested in a spine simulator. The tested segments were C4 to 7. In the first step, physiologic motion was investigated. Afterwards, the three steps of injury were dissection of the anterior longitudinal ligament, removal of the intervertebral disc/posterior longitudinal ligament, and dissection of the interspinous ligaments/ligamentum flavum. After each step, the mobility was determined. Regarding flexion and extension, an increase in motion of 8.36 % after the first step, 90.45 % after the second step, and 121.67 % after the last step was observed. Testing of lateral bending showed an increase of mobility of 7.88 %/27.48 %/33.23 %; axial rotation increased by 2.87 %/31.16 %/45.80 %. Isolated dissection of the anterior longitudinal ligament led to minor destabilization, whereas the intervertebral disc has to be seen as a major stabilizer of the cervical spine. Few finite-element studies showed comparable results. If a transfer to clinical use is undertaken, an isolated rupture of the anterior longitudinal ligament can be treated without surgical stabilization.

  11. [Application of finite element analysis in Chinese cervical manipulation biomechanics].

    Science.gov (United States)

    Wang, Huihao; Chen, Bo; Zhan, Hongsheng; Wang, Huihao; Chen, Bo; Zhan, Hongsheng

    2013-10-01

    Clinical advantages of Chinese spinal manipulation therapy (CSMT) were recognized for spinal chronic lesions of soft tissues and bones, such as cervical spondylosis, etc. However, the security of CSMT and the hypotheses of practice mechanisms were questioned for lacking of the relevant basic researches. Researches have proved that these methods could be used to observe the dynamic effects of spine with application of finite element analysis (FEA) computer technology. Combining with other biomechanical experimental methods and applying advanced FEA technology for mechanical problems of CSMT, we may not only find the mechanisms of action and provide theoretical supports for the traditional Chinese therapy, but also standardize the key techniques and optimize the treatment options improving clinical outcomes, and even promote spreading of CSMT. Computer models are ideally suited for studying phenomena that cannot be satisfactorily investigated with other models. However, computer models of CSMT practice remain to be further refined. The results which had been acquired so far not only verified some of the traditional points of view, but also revised and specified some perspectives of the past. This paper intends to review FEA studies with Chinese cervical manipulation therapy (CCMT) for cervical spinal chronic lesions of soft tissues and bones, involving different effects for cervical spine joints (pulling/traction and thrusting) with practice techniques and cervical spine soft tissues (including vessels and its hemodynamics, muscles and fasciae, etc).

  12. Adaptive sports technology and biomechanics: wheelchairs.

    Science.gov (United States)

    Cooper, Rory A; De Luigi, Arthur Jason

    2014-08-01

    Wheelchair sports are an important tool in the rehabilitation of people with severe chronic disabilities and have been a driving force for innovation in technology and practice. In this paper, we will present an overview of the adaptive technology used in Paralympic sports with a special focus on wheeled technology and the impact of design on performance (defined as achieving the greatest level of athletic ability and minimizing the risk of injury). Many advances in manual wheelchairs trace their origins to wheelchair sports. Features of wheelchairs that were used for racing and basketball 25 or more years ago have become integral to the manual wheelchairs that people now use every day; moreover, the current components used on ultralight wheelchairs also have benefitted from technological advances developed for sports wheelchairs. For example, the wheels now used on chairs for daily mobility incorporate many of the components first developed for sports chairs. Also, advances in manufacturing and the availability of aerospace materials have driven current wheelchair design and manufacture. Basic principles of sports wheelchair design are universal across sports and include fit; minimizing weight while maintaining high stiffness; minimizing rolling resistance; and optimizing the sports-specific design of the chair. However, a well-designed and fitted wheelchair is not sufficient for optimal sports performance: the athlete must be well trained, skilled, and use effective biomechanics because wheelchair athletes face some unique biomechanical challenges.

  13. 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.

  14. Biomechanics of Counterweighted One-Legged Cycling.

    Science.gov (United States)

    Elmer, Steven J; McDaniel, John; Martin, James C

    2016-02-01

    One-legged cycling has served as a valuable research tool and as a training and rehabilitation modality. Biomechanics of one-legged cycling are unnatural because the individual must actively lift the leg during flexion, which can be difficult to coordinate and cause premature fatigue. We compared ankle, knee, and hip biomechanics between two-legged, one-legged, and counterweighted (11.64 kg) one-legged cycling. Ten cyclists performed two-legged (240 W), one-legged (120 W), and counterweighted one-legged (120 W) cycling (80 rpm). Pedal forces and limb kinematics were recorded to determine work during extension and flexion. During counterweighted one-legged cycling relative ankle dorsiflexion, knee flexion, and hip flexion work were less than one-legged but greater than two-legged cycling (all P cycling were greater than one-legged but less than two-legged cycling (all P cycling reduced but did not eliminate differences in joint flexion and extension actions between one- and two-legged cycling. Even with these differences, counterweighted one-legged cycling seemed to have advantages over one-legged cycling. These results, along with previous work highlighting physiological characteristics and training adaptations to counterweighted one-legged cycling, demonstrate that this exercise is a viable alternative to one-legged cycling.

  15. 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.

  16. Biomechanical consequences of epiphytism in intertidal macroalgae.

    Science.gov (United States)

    Anderson, Laura M; Martone, Patrick T

    2014-04-01

    Epiphytic algae grow on other algae rather than hard substrata, perhaps circumventing competition for space in marine ecosystems. Aquatic epiphytes are widely thought to negatively affect host fitness; it is also possible that epiphytes benefit from associating with hosts. This study explored the biomechanical costs and benefits of the epiphytic association between the intertidal brown algal epiphyte Soranthera ulvoidea and its red algal host Odonthalia floccosa. Drag on epiphytized and unepiphytized hosts was measured in a recirculating water flume. A typical epiphyte load increased drag on hosts by ~50%, increasing dislodgment risk of epiphytized hosts compared with hosts that did not have epiphytes. However, epiphytes were more likely to dislodge from hosts than hosts were to dislodge from the substratum, suggesting that drag added by epiphytes may not be mechanically harmful to hosts if epiphytes break first. Concomitantly, epiphytes experienced reduced flow when attached to hosts, perhaps allowing them to grow larger or live in more wave-exposed areas. Biomechanical interactions between algal epiphytes and hosts are complex and not necessarily negative, which may partially explain the evolution and persistence of epiphytic relationships.

  17. 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.

  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. Morphology and biomechanical properties of cerebellar arteries in adults

    Directory of Open Access Journals (Sweden)

    Olga A. Fomkina

    2016-06-01

    Full Text Available The goal was to analyze the variability of a number of morphometric and biomechanical parameters of cerebellar arteries in adults aged 20-74 years. Material and Methods ― 179 samples of cerebellar arteries, obtained by autopsy of adults without acute cerebrovascular pathology have been studied; 24 preparations of arterial complexes «arterial circle – cerebral arteries» from scientific collection of Human Anatomy Department of Saratov State Medical University (Saratov, Russia have been also investigated. Research methods were: preparation, microscopy, experiments on uniaxial longitudinal stretching at a tensile testing machine Tira Test 28005 (TIRA GmbH, Germany. We studied outer diameter, angle of divergence, overall strength and maximal relative deformation of superior (SCA, anterior inferior (AICA and posterior inferior cerebellar arteries (PICA. Results and Conclusion ― It was revealed that SCA was characterized by the largest diameter and angle of divergence, the most strength and extensibility. AICA and PICA had no significant differences of the studied parameters. It was noted that AICA originated in the lower third part of basilar artery 1.5 times more likely than in the middle third part of this artery.

  20. Correlation between Intrinsic Patellofemoral Pain Syndrome in Young Adults and Lower Extremity Biomechanics.

    Science.gov (United States)

    Kwon, Ohjeoung; Yun, Mijung; Lee, Wanhee

    2014-07-01

    [Purpose] The purpose of this study was to evaluate the correlation between intrinsic patellofemoral pain syndrome (PFPS) in young adults and lower extremity biomechanics. [Subjects] This experiment was carried out with sixty (24 men and 32 women), who are normal university students as subjects. [Methods] All subjects underwent 3 clinical evaluations. For distinguishing the intrinsic PFPS from controls, we used the Modified Functional Index Questionnaire (MFIQ), Clarke's test and the Eccentric step test. Based on the results of the tests, subjects who were classified as positive for 2 more tests were allocated to the bilateral or unilateral intrinsic PFPS group (n=14), and the others were allocated to the control group (n=42). These two groups were tested for hamstring tightness, foot overpronation, and static Q-angle and dynamic Q-angle. These are the four lower extremity biomechanic, cited as risk factors of patellofemoral pain syndrome. [Results] The over pronation, static Q-angle and the dynamic Q-angle were not significantly different between the two groups. However, the hamstring tightness of the PFPS group was significantly greater than that of the controls. [Conclusion] We examined individuals for intrinsic patellofemoral pain syndrome in young adults and lower extremity biomechanics. We found a strong correlation between intrinsic PFPS and hamstring tightness.

  1. Cataract surgery causes biomechanical alterations to the eye detectable by Corvis ST tonometry

    Science.gov (United States)

    Kato, Yoshitake; Nakakura, Shunsuke; Asaoka, Ryo; Matsuya, Kanae; Fujio, Yuki; Kiuchi, Yoshiaki

    2017-01-01

    Purpose Modern cataract surgery is generally considered to bring about modest and sustained intraocular pressure (IOP) reduction. However, the pathophysiological mechanism for this remains unclear. Moreover, a change in ocular biomechanical properties after surgery can affect the measurement of IOP. The aim of the study is to investigate ocular biomechanics, before and following cataract surgery, using Corvis ST tonometry (CST). Patients and methods Fifty-nine eyes of 59 patients with cataract were analyzed. IOP with Goldmann applanation tonometry (IOP-G), axial length, corneal curvature and CST parameters were measured before cataract surgery and, up to 3 months, following surgery. Since CST parameters are closely related to IOP-G, linear modeling was carried out to investigate whether there was a change in CST measurements following cataract surgery, adjusted for a change in IOP-G. Results IOP-G significantly decreased after surgery (mean±standard deviation: 11.8±3.1 mmHg) compared to pre-surgery (15.2±4.3 mmHg, Pcataract surgery (Pcataract surgery (Pcataract surgery. Conclusion Corneal biomechanical properties, as measured with CST, were observed to change significantly following cataract surgery. Trial registration Japan Clinical Trials Registry UMIN000014370 PMID:28222145

  2. Finite Element-Derived Surrogate Models of Locked Plate Fracture Fixation Biomechanics.

    Science.gov (United States)

    Wee, Hwabok; Reid, J Spence; Chinchilli, Vernon M; Lewis, Gregory S

    2017-03-01

    Internal fixation of bone fractures using plates and screws involves many choices-implant type, material, sizes, and geometric configuration-made by the surgeon. These decisions can be important for providing adequate stability to promote healing and prevent implant mechanical failure. The purpose of this study was to develop mathematical models of the relationships between fracture fixation construct parameters and resulting 3D biomechanics, based on parametric computer simulations. Finite element models of hundreds of different locked plate fixation constructs for midshaft diaphyseal fractures were systematically assembled using custom algorithms, and axial, torsional, and bending loadings were simulated. Multivariate regression was used to fit response surface polynomial equations relating fixation design parameters to outputs including maximum implant stresses, axial and shear strain at the fracture site, and construct stiffness. Surrogate models with as little as three regressors showed good fitting (R (2) = 0.62-0.97). Inner working length was the strongest predictor of maximum plate and screw stresses, and a variety of quadratic and interaction terms influenced resulting biomechanics. The framework presented in this study can be applied to additional types of bone fractures to provide clinicians and implant designers with clinical insight, surgical optimization, and a comprehensive mathematical description of biomechanics.

  3. [Biomechanical characteristics of human fetal membranes. Preterm fetal membranes are stronger than term fetal membranes].

    Science.gov (United States)

    Rangaswamy, N; Abdelrahim, A; Moore, R M; Uyen, L; Mercer, B M; Mansour, J M; Kumar, D; Sawady, J; Moore, J J

    2011-06-01

    The purpose of this study was to determine the biomechanical characteristics of human fetal membranes (FM) throughout gestation. Biomechanical properties were determined for 115 FM of 23-41 weeks gestation using our previously described methodology. The areas of membrane immediately adjacent to the strongest and weakest tested spots were sampled for histomorphometric analysis. Clinical data on the patients whose FM were examined were also collected. FM less than 28 weeks gestation were associated with higher incidence of abruption and chorioamnionitis. Topographically FM at all gestations had heterogeneous biomechanical characteristics over their surfaces with distinct weak areas. The most premature membranes were the strongest. FM strength represented by rupture force and work to rupture decreased with increasing gestation in both weak and strong regions of FM. This decrease in FM strength was most dramatic at more than 38 weeks gestation. The FM component amnion-chorion sublayers were thinner in the weak areas compared to strong areas. Compared to term FM, preterm FM are stronger but have similar heterogeneous weak and strong areas. Following a gradual increase in FM weakness with increasing gestation, there is a major drop-off at term 38 weeks gestation. The FM weak areas are thinner than the stronger areas. Whether the difference in thickness is enough to account for the strength differences is unknown.

  4. Long-latency reflexes account for limb biomechanics through several supraspinal pathways

    Directory of Open Access Journals (Sweden)

    Isaac Louis Kurtzer

    2015-01-01

    Full Text Available Accurate control of body posture is enforced by a multitude of corrective actions operating over a range of time scales. The earliest correction is the short-latency reflex which occurs between 20-45 ms following a sudden displacement of the limb and is generated entirely by spinal circuits. In contrast, voluntary reactions are generated by a highly distributed network but at a significantly longer delay after stimulus onset (greater than 100 ms. Between these two epochs is the long-latency reflex (around 50-100 ms which but acts more rapidly than of voluntary reactions but shares some supraspinal pathways and functional capabilities. In particular, the long-latency reflex accounts for the arm’s biomechanical properties rather than only responding to local muscle stretch like the short-latency reflex. This paper will review how the long-latency reflex accounts for the arm’s biomechanical properties and the supraspinal pathways supporting this ability. Relevant experimental paradigms include clinical studies, non-invasive brain stimulation, neural recordings in monkeys, and human behavioral studies. The sum of this effort indicates that primary motor cortex and reticular formation contribute to the the long-latency reflex either by generating or scaling its structured response appropriate for the arm’s biomechanics whereas the cerebellum scales the magnitude of the feedback response. Additional putative pathways are discussed as well as potential research lines.

  5. Spastic paretic stiff-legged gait: biomechanics of the unaffected limb.

    Science.gov (United States)

    Kerrigan, D C; Frates, E P; Rogan, S; Riley, P O

    1999-01-01

    A concern for individuals with hemiparesis affecting their gait, which heretofore has never been studied, is the possibility that various compensations occurring in the unaffected limb may strain or fatigue the muscles or ligaments and/or predispose to joint injury in that limb. We studied the biomechanics of the unaffected limb during walking in 20 subjects with hemiparesis who had stiff-legged gait as a result of stroke. An optoelectronic motion analysis and force platform system was used to estimate torques in all three planes about the hip, knee, and ankle. Sagittal plane joint motion and power about the unaffected hip, knee, and ankle were also studied. Data were compared with control walking data collected from 20 able-bodied controls. On average, peak torques and powers were all either reduced or the same compared with controls, even though in some instances values were >2 standard deviations (SD) above the control means. Our findings suggest that on average the probability of excessive muscular-tendon effort and the risk for biomechanical injury in the unaffected limb are minimal compared with able-bodied, walking controls. However, given individual variability, we recommend routine clinical gait analysis for all people with stiff-legged gait to eliminate excessive values in certain biomechanical parameters, which could, if not addressed, predispose to muscle-tendon strain or joint or ligamentous injury.

  6. Open Knee: Open Source Modeling and Simulation in Knee Biomechanics.

    Science.gov (United States)

    Erdemir, Ahmet

    2016-02-01

    Virtual representations of the knee joint can provide clinicians, scientists, and engineers the tools to explore mechanical functions 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. Interested parties can immediately utilize readily available models for scientific discovery and 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 the detailed anatomical representation of the joint's major tissue structures and 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 is 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

  7. Teaching undergraduate biomechanics with Just-in-Time Teaching.

    Science.gov (United States)

    Riskowski, Jody L

    2015-06-01

    Biomechanics education is a vital component of kinesiology, sports medicine, and physical education, as well as for many biomedical engineering and bioengineering undergraduate programmes. Little research exists regarding effective teaching strategies for biomechanics. However, prior work suggests that student learning in undergraduate physics courses has been aided by using the Just-in-Time Teaching (JiTT). As physics understanding plays a role in biomechanics understanding, the purpose of study was to evaluate the use of a JiTT framework in an undergraduate biomechanics course. This two-year action-based research study evaluated three JiTT frameworks: (1) no JiTT; (2) mathematics-based JiTT; and (3) concept-based JiTT. A pre- and post-course assessment of student learning used the biomechanics concept inventory and a biomechanics concept map. A general linear model assessed differences between the course assessments by JiTT framework in order to evaluate learning and teaching effectiveness. The results indicated significantly higher learning gains and better conceptual understanding in a concept-based JiTT course, relative to a mathematics-based JiTT or no JiTT course structure. These results suggest that a course structure involving concept-based questions using a JiTT strategy may be an effective method for engaging undergraduate students and promoting learning in biomechanics courses.

  8. 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.

  9. The scapular neck fracture : biomechanical, clinical and surgical aspects

    NARCIS (Netherlands)

    Noort, Arthur van

    2005-01-01

    After a short introduction to the topics of this thesis, in chapter 2 we described the functional and radiological results of a retrospective study in patients with an ipsilateral scapular neck and clavicular shaft fracture (floating shoulder). Forty-six patients were treated between 1991 and 1996.

  10. Frontiers in Head and Neck Trauma: Clinical and Biomechanical.

    Science.gov (United States)

    2007-11-02

    the frontal, parietal and occipital bones that form the bulk of the convexity on top . The lateral aspect of the sphenoid bone meets the temporal bone...Bones The facial bones consist of fourteen bones: two nasal, two superior maxillary , two lachrymal, two malar, two palate, two inferior turbinate...vomer and inferior maxillary bones. These bones form the housing for most of the sensory structures of the human, including sight, smell and taste

  11. "Pinching subacromial problems” - A clinical and biomechanical approach -

    NARCIS (Netherlands)

    Witte, Pieter Bas de

    2015-01-01

    The Subacromial Impingement Syndrome (SIS) is the most prevalent disorder of the shoulder in primary health care. Acromionplasty, as the main surgical treatment of SIS, is one of the most performed orthopedic surgeries. However, its results are highly variable. Possibly, there are different etiologi

  12. Graft Biomechanics Following Three Corneal Transplantation Techniques

    Science.gov (United States)

    Feizi, Sepehr; Montahai, Talieh; Moein, Hamidreza

    2015-01-01

    Purpose: To compare corneal biomechanical properties following three different transplantation techniques, including Descemet stripping automated endothelial keratoplasty (DSAEK), deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in comparison to normal eyes. Methods: This cross-sectional comparative study included 118 eyes: 17 eyes of 17 patients received DSAEK, 23 eyes of 21 patients underwent DALK using Anwar's big bubble technique, and 45 eyes of 36 patients had PK; 33 right eyes of 33 normal subjects served as the control group. Using the ocular response analyzer (ORA, Reichert Ophthalmic Instruments, Buffalo, New York, USA), corneal hysteresis (CH) and corneal resistance factor (CRF) were measured and compared among the study groups at least 3 months after all sutures were removed. Results: Mean patient age was 26.9 ± 5.0 years in the control group, 28.8 ± 4.2 in the PK group, 27.2 ± 6.5 in the DALK group, and 62.5 ± 16.8 in the DSAEK group (P < 0.001). Central corneal thickness (CCT) was 539.0 ± 24.8, 567.5 ± 38.8, 547.0 ± 42.6 and 631.1 ± 84.8 μm, respectively (P < 0.001). CH and CRF were significantly lower in the DSAEK group (7.79 ± 2.0 and 7.88 ± 1.74 mmHg, respectively) as compared to the PK (10.23 ± 2.07 and 10.13 ± 2.22 mmHg, respectively) and DALK (9.64 ± 2.07 and 9.36 ± 2.09 mmHg, respectively) groups. The two latter groups demonstrated biomechanical parameters comparable to normal subjects (9.84 ± 1.59 and 9.89 ± 1.73 mmHg, respectively). Conclusion: Graft biomechanical parameters after DSAEK are lower than those following PK and DALK. After PK and DALK in keratoconic eyes, these metrics are increased to normal values. These differences may have implications for interpreting intraocular pressure or planning graft refractive surgery after keratoplasty. PMID:26730307

  13. 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).

  14. Comparison of expansive pedicle screw and polymethylmethacrylate-augmented pedicle screw in osteoporotic sheep lumbar vertebrae: biomechanical and interfacial evaluations.

    Directory of Open Access Journals (Sweden)

    Da Liu

    Full Text Available BACKGROUND: It was reported that expansive pedicle screw (EPS and polymethylmethacrylate-augmented pedicle screw (PMMA-PS could be used to increase screw stability in osteoporosis. However, there are no studies comparing the two kinds of screws in vivo. Thus, we aimed to compare biomechanical and interfacial performances of EPS and PMMA-PS in osteoporotic sheep spine. METHODOLOGY/PRINCIPAL FINDINGS: After successful induction of osteoporotic sheep, lumbar vertebrae in each sheep were randomly divided into three groups. The conventional pedicle screw (CPS was inserted directly into vertebrae in CPS group; PMMA was injected prior to insertion of CPS in PMMA-PS group; and the EPS was inserted in EPS group. Sheep were killed and biomechanical tests, micro-CT analysis and histological observation were performed at both 6 and 12 weeks post-operation. At 6-week and 12-week, screw stabilities in EPS and PMMA-PS groups were significantly higher than that in CPS group, but there were no significant differences between EPS and PMMA-PS groups at two study periods. The screw stability in EPS group at 12-week was significantly higher than that at 6-week. The bone trabeculae around the expanding anterior part of EPS were more and denser than that in CPS group at 6-week and 12-week. PMMA was found without any degradation and absorption forming non-biological "screw-PMMA-bone" interface in PMMA-PS group, however, more and more bone trabeculae surrounded anterior part of EPS improving local bone quality and formed biological "screw-bone" interface. CONCLUSIONS/SIGNIFICANCE: EPS can markedly enhance screw stability with a similar effect to the traditional method of screw augmentation with PMMA in initial surgery in osteoporosis. EPS can form better biological interface between screw and bone than PMMA-PS. In addition, EPS have no risk of thermal injury, leakage and compression caused by PMMA. We propose EPS has a great application potential in augmentation of

  15. Biomechanics trends in modeling and simulation

    CERN Document Server

    Ogden, Ray

    2017-01-01

    The book presents a state-of-the-art overview of biomechanical and mechanobiological modeling and simulation of soft biological tissues. Seven well-known scientists working in that particular field discuss topics such as biomolecules, networks and cells as well as failure, multi-scale, agent-based, bio-chemo-mechanical and finite element models appropriate for computational analysis. Applications include arteries, the heart, vascular stents and valve implants as well as adipose, brain, collagenous and engineered tissues. The mechanics of the whole cell and sub-cellular components as well as the extracellular matrix structure and mechanotransduction are described. In particular, the formation and remodeling of stress fibers, cytoskeletal contractility, cell adhesion and the mechanical regulation of fibroblast migration in healing myocardial infarcts are discussed. The essential ingredients of continuum mechanics are provided. Constitutive models of fiber-reinforced materials with an emphasis on arterial walls ...

  16. Research in biomechanics of occupant protection.

    Science.gov (United States)

    King, A I; Yang, K H

    1995-04-01

    This paper discusses the biomechanical bases for occupant protection against frontal and side impact. Newton's Laws of Motion are used to illustrate the effect of a crash on restrained and unrestrained occupants, and the concept of ride down is discussed. Occupant protection through the use of energy absorbing materials is described, and the mechanism of injury of some of the more common injuries is explained. The role of the three-point belt and the airbag in frontal protection is discussed along with the potential injuries that can result from the use of these restraint systems. Side impact protection is more difficult to attain but some protection can be derived from the use of padding or a side impact airbag. It is concluded that the front seat occupants are adequately protected against frontal impact if belts are worn in an airbag equipped vehicle. Side impact protection may not be uniform in all vehicles.

  17. Biomechanics of Posterior Dynamic Stabilization Systems

    Directory of Open Access Journals (Sweden)

    D. U. Erbulut

    2013-01-01

    Full Text Available Spinal rigid instrumentations have been used to fuse and stabilize spinal segments as a surgical treatment for various spinal disorders to date. This technology provides immediate stability after surgery until the natural fusion mass develops. At present, rigid fixation is the current gold standard in surgical treatment of chronic back pain spinal disorders. However, such systems have several drawbacks such as higher mechanical stress on the adjacent segment, leading to long-term degenerative changes and hypermobility that often necessitate additional fusion surgery. Dynamic stabilization systems have been suggested to address adjacent segment degeneration, which is considered to be a fusion-associated phenomenon. Dynamic stabilization systems are designed to preserve segmental stability, to keep the treated segment mobile, and to reduce or eliminate degenerative effects on adjacent segments. This paper aimed to describe the biomechanical aspect of dynamic stabilization systems as an alternative treatment to fusion for certain patients.

  18. Biomechanics of the elbow in sports.

    Science.gov (United States)

    Loftice, Jeremy; Fleisig, Glenn S; Zheng, Nigel; Andrews, James R

    2004-10-01

    In throwing activities, the elbow is sometimes stressed to its biomechanical limits. In this article, forces, torques, angular velocities, and muscle activity about the elbow are reviewed for the baseball pitch, the football pass, the javelin throw, the windmill softball pitch, the tennis serve, and the golf swing. The elbow goes through rapid extension in baseball pitching (about 2400 degrees/s) and rapid flexion in the javelin throw (about 1900 degrees/s). During baseball pitching, the elbow joint is subject to a valgus torque reaching 64 Nm, and requires proximal forces as high as 1000 N to prevent elbow distraction. The ulnar collateral ligament (UCL) rupture in baseball pitching, lateral epicondylitis in the tennis backhand, and other injury mechanisms are also discussed.

  19. Fibrillin: from microfibril assembly to biomechanical function.

    Science.gov (United States)

    Kielty, Cay M; Baldock, Clair; Lee, David; Rock, Matthew J; Ashworth, Jane L; Shuttleworth, C Adrian

    2002-02-28

    Fibrillins form the structural framework of a unique and essential class of extracellular microfibrils that endow dynamic connective tissues with long-range elasticity. Their biological importance is emphasized by the linkage of fibrillin mutations to Marfan syndrome and related connective tissue disorders, which are associated with severe cardiovascular, ocular and skeletal defects. These microfibrils have a complex ultrastructure and it has proved a major challenge both to define their structural organization and to relate it to their biological function. However, new approaches have at last begun to reveal important insights into their molecular assembly, structural organization and biomechanical properties. This paper describes the current understanding of the molecular assembly of fibrillin molecules, the alignment of fibrillin molecules within microfibrils and the unique elastomeric properties of microfibrils.

  20. 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.

  1. Integrative Role Of Cinematography In Biomechanics Research

    Science.gov (United States)

    Zernicke, Ronald F.; Gregor, Robert J.

    1982-02-01

    Cinematography is an integral element in the interdisciplinary biomechanics research conducted in the Department of Kinesiology at the University of California, Los Angeles. For either an isolated recording of a movement phenomenon or as a recording component which is synchronized with additional transducers and recording equipment, high speed motion picture film has been effectively incorporated into resr'arch projects ranging from two and three dimensional analyses of human movements, locomotor mechanics of cursorial mammals and primates, to the structural responses and dynamic geometries of skeletal muscles, tendons, and ligaments. The basic equipment used in these studies includes three, 16 mm high speed, pin-registered cameras which have the capacity for electronic phase-locking. Crystal oscillators provide the generator pulses to synchronize the timing lights of the cameras and the analog-to-digital recording equipment. A rear-projection system with a sonic digitizer permits quantification of film coordinates which are stored on computer disks. The capacity for synchronizing the high speed films with additional recording equipment provides an effective means of obtaining not only position-time data from film, but also electromyographic, force platform, tendon force transducer, and strain gauge recordings from tissues or moving organisms. During the past few years, biomechanics research which comprised human studies has used both planar and three-dimensional cinematographic techniques. The studies included planar analyses which range from the gait characteristics of lower extremity child amputees to the running kinematics and kinetics of highly skilled sprinters and long-distance runners. The dynamics of race cycling and kinetics of gymnastic maneuvers were studied with cinematography and either a multi-dimensional force platform or a bicycle pedal with strain gauges to determine the time histories of the applied forces. The three-dimensional technique

  2. Pathogenesis of varicose veins - lessons from biomechanics.

    Science.gov (United States)

    Pfisterer, Larissa; König, Gerd; Hecker, Markus; Korff, Thomas

    2014-03-01

    The development of varicose veins or chronic venous insufficiency is preceded by and associated with the pathophysiological remodelling of the venous wall. Recent work suggests that an increase in venous filling pressure is sufficient to promote varicose remodelling of veins by augmenting wall stress and activating venous endothelial and smooth muscle cells. In line with this, known risk factors such as prolonged standing or an obesity-induced increase in venous filling pressure may contribute to varicosis. This review focuses on biomechanically mediated mechanisms such as an increase in wall stress caused by venous hypertension or alterations in blood flow, which may be involved in the onset of varicose vein development. Finally, possible therapeutic options to counteract or delay the progress of this venous disease are discussed.

  3. 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.

  4. 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.

  5. Development of a biomechanical energy harvester

    Science.gov (United States)

    Li, Qingguo; Naing, Veronica; Donelan, J Maxwell

    2009-01-01

    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. PMID:19549313

  6. Biomechanics of sprint running. A review.

    Science.gov (United States)

    Mero, A; Komi, P V; Gregor, R J

    1992-06-01

    Understanding of biomechanical factors in sprint running is useful because of their critical value to performance. Some variables measured in distance running are also important in sprint running. Significant factors include: reaction time, technique, electromyographic (EMG) activity, force production, neural factors and muscle structure. Although various methodologies have been used, results are clear and conclusions can be made. The reaction time of good athletes is short, but it does not correlate with performance levels. Sprint technique has been well analysed during acceleration, constant velocity and deceleration of the velocity curve. At the beginning of the sprint run, it is important to produce great force/power and generate high velocity in the block and acceleration phases. During the constant-speed phase, the events immediately before and during the braking phase are important in increasing explosive force/power and efficiency of movement in the propulsion phase. There are no research results available regarding force production in the sprint-deceleration phase. The EMG activity pattern of the main sprint muscles is described in the literature, but there is a need for research with highly skilled sprinters to better understand the simultaneous operation of many muscles. Skeletal muscle fibre characteristics are related to the selection of talent and the training-induced effects in sprint running. Efficient sprint running requires an optimal combination between the examined biomechanical variables and external factors such as footwear, ground and air resistance. Further research work is needed especially in the area of nervous system, muscles and force and power production during sprint running. Combining these with the measurements of sprinting economy and efficiency more knowledge can be achieved in the near future.

  7. Non-clinical studies in the process of new drug development - Part II: Good laboratory practice, metabolism, pharmacokinetics, safety and dose translation to clinical studies

    Directory of Open Access Journals (Sweden)

    E.L. Andrade

    Full Text Available The process of drug development involves non-clinical and clinical studies. Non-clinical studies are conducted using different protocols including animal studies, which mostly follow the Good Laboratory Practice (GLP regulations. During the early pre-clinical development process, also known as Go/No-Go decision, a drug candidate needs to pass through several steps, such as determination of drug availability (studies on pharmacokinetics, absorption, distribution, metabolism and elimination (ADME and preliminary studies that aim to investigate the candidate safety including genotoxicity, mutagenicity, safety pharmacology and general toxicology. These preliminary studies generally do not need to comply with GLP regulations. These studies aim at investigating the drug safety to obtain the first information about its tolerability in different systems that are relevant for further decisions. There are, however, other studies that should be performed according to GLP standards and are mandatory for the safe exposure to humans, such as repeated dose toxicity, genotoxicity and safety pharmacology. These studies must be conducted before the Investigational New Drug (IND application. The package of non-clinical studies should cover all information needed for the safe transposition of drugs from animals to humans, generally based on the non-observed adverse effect level (NOAEL obtained from general toxicity studies. After IND approval, other GLP experiments for the evaluation of chronic toxicity, reproductive and developmental toxicity, carcinogenicity and genotoxicity, are carried out during the clinical phase of development. However, the necessity of performing such studies depends on the new drug clinical application purpose.

  8. Non-clinical studies in the process of new drug development - Part II: Good laboratory practice, metabolism, pharmacokinetics, safety and dose translation to clinical studies.

    Science.gov (United States)

    Andrade, E L; Bento, A F; Cavalli, J; Oliveira, S K; Schwanke, R C; Siqueira, J M; Freitas, C S; Marcon, R; Calixto, J B

    2016-12-12

    The process of drug development involves non-clinical and clinical studies. Non-clinical studies are conducted using different protocols including animal studies, which mostly follow the Good Laboratory Practice (GLP) regulations. During the early pre-clinical development process, also known as Go/No-Go decision, a drug candidate needs to pass through several steps, such as determination of drug availability (studies on pharmacokinetics), absorption, distribution, metabolism and elimination (ADME) and preliminary studies that aim to investigate the candidate safety including genotoxicity, mutagenicity, safety pharmacology and general toxicology. These preliminary studies generally do not need to comply with GLP regulations. These studies aim at investigating the drug safety to obtain the first information about its tolerability in different systems that are relevant for further decisions. There are, however, other studies that should be performed according to GLP standards and are mandatory for the safe exposure to humans, such as repeated dose toxicity, genotoxicity and safety pharmacology. These studies must be conducted before the Investigational New Drug (IND) application. The package of non-clinical studies should cover all information needed for the safe transposition of drugs from animals to humans, generally based on the non-observed adverse effect level (NOAEL) obtained from general toxicity studies. After IND approval, other GLP experiments for the evaluation of chronic toxicity, reproductive and developmental toxicity, carcinogenicity and genotoxicity, are carried out during the clinical phase of development. However, the necessity of performing such studies depends on the new drug clinical application purpose.

  9. Investigation of the influence of design details on short implant biomechanics using colorimetric photoelastic analysis: a pilot study

    Directory of Open Access Journals (Sweden)

    João César Zielak

    Full Text Available Introduction : The clinical survival of a dental implant is directly related to its biomechanical behavior. Since short implants present lower bone/implant contact area, their design may be more critical to stress distribution to surrounding tissues. Photoelastic analysis is a biomechanical method that uses either simple qualitative results or complex calculations for the acquisition of quantitative data. In order to simplify data acquisition, we performed a pilot study to demonstrate the investigation of biomechanics via correlation of the findings of colorimetric photoelastic analysis (stress transition areas; STAs of design details between two types of short dental implants under axial loads. Methods Implants were embedded in a soft photoelastic resin and axially loaded with 10 and 20 N of force. Implant design features were correlated with the STAs (mm2 of the colored fringes of colorimetric photoelastic analysis. Results Under a 10 N load, the surface area of the implants was directly related to STA, whereas under a 20 N load, the surface area and thread height were inversely related to STA. Conclusion A smaller external thread height seemed to improve the biomechanical performance of the short implants investigated.

  10. Trunk biomechanics and its association with hip and knee kinematics in patients with and without patellofemoral pain.

    Science.gov (United States)

    Nakagawa, Theresa Helissa; Maciel, Carlos Dias; Serrão, Fábio Viadanna

    2015-02-01

    Patellofemoral pain (PFP) is a common lower extremity condition observed in sports clinics. Recently, it has been suggested that trunk motion could affect hip and knee biomechanics in the frontal plane. Thus, the purpose of the study was compare trunk kinematics, strength and muscle activation between people with PFP and healthy participants. In addition, the associations among trunk biomechanics, hip and knee kinematics were analysed. Thirty people with PFP and thirty pain-free individuals participated. The peak ipsilateral trunk lean, hip adduction, and knee abduction were evaluated with an electromagnetic tracking system, and the surface electromyographic signals of the iliocostalis and external oblique muscle were recorded during single-leg squats. Trunk extension and trunk flexion with rotation isometric strength and side bridge tests were quantified using a handheld dynamometer. Compared with the control group, the PFP group demonstrated increased ipsilateral trunk lean, hip adduction and knee abduction (p = 0.02-0.04) during single-leg squat accompanied with decreased trunk isometric strength (p = biomechanics were found in people with PFP. No relationship among trunk, hip and knee biomechanics was found in the PFP group, suggesting that people with PFP show different movement patterns compared to the control group.

  11. Biomechanical and biocompatibility characteristics of electrospun polymeric tracheal scaffolds.

    Science.gov (United States)

    Ajalloueian, Fatemeh; Lim, Mei Ling; Lemon, Greg; Haag, Johannes C; Gustafsson, Ylva; Sjöqvist, Sebastian; Beltrán-Rodríguez, Antonio; Del Gaudio, Costantino; Baiguera, Silvia; Bianco, Alessandra; Jungebluth, Philipp; Macchiarini, Paolo

    2014-07-01

    The development of tracheal scaffolds fabricated based on electrospinning technique by applying different ratios of polyethylene terephthalate (PET) and polyurethane (PU) is introduced here. Prior to clinical implantation, evaluations of biomechanical and morphological properties, as well as biocompatibility and cell adhesion verifications are required and extensively performed on each scaffold type. However, the need for bioreactors and large cell numbers may delay the verification process during the early assessment phase. Hence, we investigated the feasibility of performing biocompatibility verification using static instead of dynamic culture. We performed bioreactor seeding on 3-dimensional (3-D) tracheal scaffolds (PET/PU and PET) and correlated the quantitative and qualitative results with 2-dimensional (2-D) sheets seeded under static conditions. We found that an 8-fold reduction for 2-D static seeding density can essentially provide validation on the qualitative and quantitative evaluations for 3-D scaffolds. In vitro studies revealed that there was notably better cell attachment on PET sheets/scaffolds than with the polyblend. However, the in vivo outcomes of cell seeded PET/PU and PET scaffolds in an orthotopic transplantation model in rodents were similar. They showed that both the scaffold types satisfied biocompatibility requirements and integrated well with the adjacent tissue without any observation of necrosis within 30 days of implantation.

  12. Keratoconus: A biomechanical perspective on loss of corneal stiffness

    Directory of Open Access Journals (Sweden)

    Abhijit Sinha Roy

    2013-01-01

    Full Text Available Keratoconus (KC is progressive disease of corneal thinning, steepening and collagen degradation. Biomechanics of the cornea is maintained by the intricate collagen network, which is responsible for its unique shape and function. With the disruption of this collagen network, the cornea loses its shape and function, resulting in progressive visual degradation. While KC is essentially a stromal disease, there is evidence that the epithelium undergoes significant thinning similar to the stroma. Several topographical approaches have been developed to detect KC early. However, it is now hypothesized that biomechanical destabilization of the cornea may precede topographic evidence of KC. Biomechanics of KC has been investigated only to a limited extent due to lack of in vivo measurement techniques and/or devices. In this review, we focus on recent work performed to characterize the biomechanical characteristics of KC.

  13. Sex differences in E-navigation: Biomechanics versus Cognition

    OpenAIRE

    2011-01-01

    Van Mierlo, C. M., Jarodzka, H., Kirschner, F., & Kirschner, P. A. (2011, 8 September). Sex differences in E-navigation: Biomechanics versus Cognition. Presentation at Learning & Cognition Plenair, Heerlen, The Netherlands.

  14. On seed physiology, biomechanics and plant phenology in Eragrostis tef

    NARCIS (Netherlands)

    Delden, van S.H.

    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 g

  15. 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'.

  16. Biomechanics and biomimetics in insect-inspired flight systems

    Science.gov (United States)

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

    2016-01-01

    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 104–105 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

  17. Biomechanical analysis of the main masticatory muscles in the rabbit.

    Science.gov (United States)

    Baron, P; Debussy, T

    1980-09-01

    The main masticatory muscles of the Rabbit (Oryctolagus cuniculus L.) were divided into their 25 component bundles per side. 5 dry skulls were used to determine points of origin and insertion which were then projected onto 3 planes perpendicular to each other, for the establishment of a biomechanical model. By interpreting this model and by examining various mandibular movements, the bundles were classified into 16 functional groups. The findings of other biomechanical studies are contrasted with the results of the study.

  18. The effect of breast support on running biomechanics

    OpenAIRE

    Milligan, Alexandra

    2013-01-01

    Whilst sports bras have been reported to significantly reduce breast kinematics and exercise-related breast pain, little is known about the effect of breast support on running biomechanics. This research area has novel applications and many potential benefits to female athletes. Papers available within this area hypothesise that the reduction of breast kinematics and exercise-related breast pain, provided by a high breast support, ensures running biomechanics are maintained and potentially en...

  19. Interpreting locomotor biomechanics from the morphology of human footprints.

    Science.gov (United States)

    Hatala, Kevin G; Wunderlich, Roshna E; Dingwall, Heather L; Richmond, Brian G

    2016-01-01

    Fossil hominin footprints offer unique direct windows to the locomotor behaviors of our ancestors. These data could allow a clearer understanding of the evolution of human locomotion by circumventing issues associated with indirect interpretations of habitual locomotor patterns from fossil skeletal material. However, before we can use fossil hominin footprints to understand better the evolution of human locomotion, we must first develop an understanding of how locomotor biomechanics are preserved in, and can be inferred from, footprint morphologies. In this experimental study, 41 habitually barefoot modern humans created footprints under controlled conditions in which variables related to locomotor biomechanics could be quantified. Measurements of regional topography (depth) were taken from 3D models of those footprints, and principal components analysis was used to identify orthogonal axes that described the largest proportions of topographic variance within the human experimental sample. Linear mixed effects models were used to quantify the influences of biomechanical variables on the first five principal axes of footprint topographic variation, thus providing new information on the biomechanical variables most evidently expressed in the morphology of human footprints. The footprint's overall depth was considered as a confounding variable, since biomechanics may be linked to the extent to which a substrate deforms. Three of five axes showed statistically significant relationships with variables related to both locomotor biomechanics and substrate displacement; one axis was influenced only by biomechanics and another only by the overall depth of the footprint. Principal axes of footprint morphological variation were significantly related to gait type (walking or running), kinematics of the hip and ankle joints and the distribution of pressure beneath the foot. These results provide the first quantitative framework for developing hypotheses regarding the

  20. Integrative biomechanics for tree ecology: beyond wood density and strength

    OpenAIRE

    Fournier, Mériem; Dlouhà, Jana; Jaouen, Gaëlle; Almeras, Tancrède

    2013-01-01

    International audience; Functional ecology has long considered the support function as important, but its biomechanical complexity is only just being elucidated. We show here that it can be described on the basis of four biomechanical traits, two safety traits against winds (SW) and self-buckling (SB), and two motricity traits involved in sustaining an upright position, tropic motion velocity (MV) and posture control (PC). All these traits are integrated at the tree scale, combining tree size...

  1. Iliotibial Band Syndrome in Runners: Biomechanical Implications and Exercise Interventions.

    Science.gov (United States)

    Baker, Robert L; Fredericson, Michael

    2016-02-01

    Iliotibial band syndrome (ITBS) has known biomechanical factors with an unclear explanation based on only strength and flexibility deficits. Neuromuscular coordination has emerged as a likely reason for kinematic faults guiding research toward motor control. This article discusses ITBS in relation to muscle performance factors, fascial considerations, epidemiology, functional anatomy, strength deficits, kinematics, iliotibial strain and strain rate, and biomechanical considerations. Evidence-based exercise approaches are reviewed for ITBS, including related methods used to train the posterior hip muscles.

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

    Science.gov (United States)

    Sun, Fei; Crisóstomo, Verónica; Báez-Díaz, Claudia; Sánchez, Francisco M

    2016-01-01

    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.

  3. 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.

  4. Biomechanics and biorheology of red blood cells in sickle cell anemia

    Science.gov (United States)

    Li, Xuejin; Dao, Ming; Lykotrafitis, George; Karniadakis, George Em

    2017-01-01

    Sickle cell anemia (SCA) is an inherited blood disorder that causes painful crises due to vaso-occlusion of small blood vessels. The primary cause of the clinical phenotype of SCA is the intracellular polymerization of sickle hemoglobin resulting in sickling of red blood cells (RBCs) in deoxygenated conditions. In this review, we discuss the biomechanical and biorheological characteristics of sickle RBCs and sickle blood as well as their implications toward a better understanding of the pathophysiology and pathogenesis of SCA. Additionally, we highlight the adhesive heterogeneity of RBCs in SCA and their specific contribution to vaso-occlusive crisis. PMID:27876368

  5. Biomechanics and biorheology of red blood cells in sickle cell anemia.

    Science.gov (United States)

    Li, Xuejin; Dao, Ming; Lykotrafitis, George; Karniadakis, George Em

    2017-01-04

    Sickle cell anemia (SCA) is an inherited blood disorder that causes painful crises due to vaso-occlusion of small blood vessels. The primary cause of the clinical phenotype of SCA is the intracellular polymerization of sickle hemoglobin resulting in sickling of red blood cells (RBCs) in deoxygenated conditions. In this review, we discuss the biomechanical and biorheological characteristics of sickle RBCs and sickle blood as well as their implications toward a better understanding of the pathophysiology and pathogenesis of SCA. Additionally, we highlight the adhesive heterogeneity of RBCs in SCA and their specific contribution to vaso-occlusive crisis.

  6. The Scandinavian Total Ankle Replacement and the ideal biomechanical requirements of ankle replacements.

    Science.gov (United States)

    Robati, Shibby; Salih, Alan; Ghosh, Koushik; Vinayakam, Parthiban

    2016-03-01

    The complex anatomy of the articular bone surfaces, ligaments, tendon attachments and muscles makes the ankle joint difficult to replicate in prosthetic replacements. Ever since the early 1970s, which saw the dawn of the first total ankle replacements, there have been numerous other attempts at replicating the joint, often with poor clinical outcomes. The anatomy of the ankle is discussed, followed by evidence of the normal ankle biomechanics and the ideal requirements of an ankle replacement. We focus on the Scandinavian Total Ankle Replacement and evaluate whether these requirements have been met.

  7. 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.

  8. 临床护理兼职教师培训模式的研究%Study on the training model of clinical nursing part-time teachers

    Institute of Scientific and Technical Information of China (English)

    汪建国; 鲁娟; 曾友燕

    2010-01-01

    本文介绍了教学医院临床护理兼职教师培训模式的实践过程,探讨了临床护理兼职教师的聘任条件、选聘程序、教学培训、绩效考评等师资队伍建设关键环节的举措.强调要提高临床护理教学质量,必须树立以学生为中心的教育观,建立兼职教师准入制度、设立有效的竞争激励机制和科学、公正的兼职教师教学评价体系,稳定和促进临床护理兼职教师队伍的可持续发展.%An effective training model of clinical part-time nursing teachers was introduced in this article, and its key measures including the part-time teachers' qualification, the procedure to engage, teaching skill training plan, performance review were defined.It emphasize that the students-centered educational view, scientific part-time nursing teachers' admittance system, effective competition mechanism and fair teaching evaluation system are not only helpful for the stability and continual development of clinical part-time nursing staff but also improving the quality of clinical nursing education.

  9. Current status of temporomandibular joint disorders and the therapeutic system derived from a series of biomechanical, histological, and biochemical studies

    OpenAIRE

    Kazuo Tanne; Yuki Okamoto; Shao-Ching Su; Tomomi Mitsuyoshi; Yuki Asakawa-Tanne; Kotaro Tanimoto

    2015-01-01

    This article was designed to report the current status of temporomandibular joint disorders (TMDs) and the therapeutic system on the basis of a series of clinical, biomechanical, histological and biochemical studies in our research groups. In particular, we have focused on the association of degenerative changes of articular cartilage in the mandibular condyle and the resultant progressive condylar resorption with mechanical stimuli acting on the condyle during the stomatognathic function. In...

  10. Tips for a physician in getting the right job, part IV: types of interviews for a clinical position.

    Science.gov (United States)

    Harolds, Jay A

    2013-11-01

    Most physicians interviewing for a job are seeking a clinical position. There are many different types of interviews for such employment, and this article enumerates the types of interviews and some characteristics of each.

  11. Consensus statement on continuous EEG in critically Ill adults and children, Part II: Personnel, technical specifications, and clinical practice

    OpenAIRE

    Herman, ST; Abend, NS; Bleck, TP; Chapman, KE; Drislane, FW; Emerson, RG; Gerard, EE; Hahn, CD; Husain, AM; Kaplan, PW; LaRoche, SM; Nuwer, MR; Quigg, M; Riviello, JJ; Schmitt, SE

    2015-01-01

    © 2015 by the American Clinical Neurophysiology Society.. Introduction: Critical Care Continuous EEG (CCEEG) is a common procedure to monitor brain function in patients with altered mental status in intensive care units. There is significant variability in patient populations undergoing CCEEG and in technical specifications for CCEEG performance. Methods: The Critical Care Continuous EEG Task Force of the American Clinical Neurophysiology Society developed expert consensus recommendations on ...

  12. C2-fractures: part II. A morphometrical analysis of computerized atlantoaxial motion, anatomical alignment and related clinical outcomes

    OpenAIRE

    Koller, Heiko; Acosta, Frank; Forstner, Rosemarie; Zenner, Juliane; Resch,Herbert; Tauber, Mark; Lederer, Stefan; Auffarth, Alexander; Hitzl, Wolfgang

    2009-01-01

    Knowledge on the outcome of C2-fractures is founded on heterogenous samples with cross-sectional outcome assessment focusing on union rates, complications and technical concerns related to surgical treatment. Reproducible clinical and functional outcome assessments are scant. Validated generic and disease specific outcome measures were rarely applied. Therefore, the aim of the current study is to investigate the radiographic, functional and clinical outcome of a patient sample with C2-fractur...

  13. [Angle-fixed plate fixation or double-plate osteosynthesis in fractures of the proximal humerus: a biomechanical study].

    Science.gov (United States)

    Hessmann, Martin H; Korner, Jan; Hofmann, Alexander; Sternstein, Werner; Rommens, Pol M

    2008-06-01

    Internal fixation of fractures of the proximal humerus needs a high stability of fixation to avoid secondary loss of fixation. This is especially important in osteoporotic bone. In an experimental study, the biomechanical properties of the angle-fixed Philos plate (internal fixator) and a double-plate osteosynthesis using two one-third tubular plates were assessed. The fracture model was an unstable three-part fracture (AO type B2). Eight pairs of human cadaveric humeri were submitted to axial load and torque. In the first part of the study, it was assessed to which degree the original stiffness of the humeri could be restored after the osteotomy by the osteosynthesis procedure. Subsequently, subsidence during 200 cycles of axial loading and torque was analysed. During axial loading, the Philos plate was significantly stiffer and showed less irreversible deformation. Two double-plate fixations, but none of the Philos plate osteosynthesis, failed. During torsion, there were no significant differences between the two implants. From the biomechanical point of view, the angle-fixed Philos plate represents the implant of choice for the surgical fixation of highly unstable three-part fractures of the proximal humerus, as the internal fixator system is characterised by superior biomechanical properties.

  14. Digital image measurement of specimen deformation based on CCD cameras and Image J software: an application to human pelvic biomechanics

    Science.gov (United States)

    Jia, Yongwei; Cheng, Liming; Yu, Guangrong; Lou, Yongjian; Yu, Yan; Chen, Bo; Ding, Zuquan

    2008-03-01

    A method of digital image measurement of specimen deformation based on CCD cameras and Image J software was developed. This method was used to measure the biomechanics behavior of human pelvis. Six cadaveric specimens from the third lumbar vertebra to the proximal 1/3 part of femur were tested. The specimens without any structural abnormalities were dissected of all soft tissue, sparing the hip joint capsules and the ligaments of the pelvic ring and floor. Markers with black dot on white background were affixed to the key regions of the pelvis. Axial loading from the proximal lumbar was applied by MTS in the gradient of 0N to 500N, which simulated the double feet standing stance. The anterior and lateral images of the specimen were obtained through two CCD cameras. Based on Image J software, digital image processing software, which can be freely downloaded from the National Institutes of Health, digital 8-bit images were processed. The procedure includes the recognition of digital marker, image invert, sub-pixel reconstruction, image segmentation, center of mass algorithm based on weighted average of pixel gray values. Vertical displacements of S1 (the first sacral vertebrae) in front view and micro-angular rotation of sacroiliac joint in lateral view were calculated according to the marker movement. The results of digital image measurement showed as following: marker image correlation before and after deformation was excellent. The average correlation coefficient was about 0.983. According to the 768 × 576 pixels image (pixel size 0.68mm × 0.68mm), the precision of the displacement detected in our experiment was about 0.018 pixels and the comparatively error could achieve 1.11\\perthou. The average vertical displacement of S1 of the pelvis was 0.8356+/-0.2830mm under vertical load of 500 Newtons and the average micro-angular rotation of sacroiliac joint in lateral view was 0.584+/-0.221°. The load-displacement curves obtained from our optical measure system

  15. Anatomy and biomechanics of quadratus lumborum.

    Science.gov (United States)

    Phillips, S; Mercer, S; Bogduk, N

    2008-02-01

    Various actions on the lumbar spine have been attributed to quadratus lumborum, but they have not been substantiated by quantitative data. The present study was undertaken to determine the magnitude of forces and moments that quadratus lumborum could exert on the lumbar spine. The fascicular anatomy of quadratus lumborum was studied in six embalmed cadavers. For each fascicle, the sites of attachment, orientation, and physiological cross-sectional area were determined. The fascicular anatomy varied considerably, between sides and between specimens, with respect to the number of fascicles, their prevalence, and their sizes. Approximately half of the fascicles act on the twelfth rib, and the rest act on the lumbar spine. The more consistently present fascicles were incorporated, as force-equivalents, into a model of quadratus lumborum in order to determine its possible actions. The magnitudes of the compression forces exerted by quadratus lumborum on the lumbar spine, the extensor moment, and the lateral bending moment, were each no greater than 10 per cent of those exerted by erector spinae and multifidus. These data indicate that quadratus lumborum has no more than a modest action on the lumbar spine, in quantitative terms. Its actual role in spinal biomechanics has still to be determined.

  16. Biomechanics of seat belt restraint system.

    Science.gov (United States)

    Sances, Anthony; Kumaresan, Srirangam; Herbst, Brian; Meyer, Steve; Hock, Davis

    2004-01-01

    Seat belt system restrains and protects occupants in motor vehicle crashes and any slack in seat belt system induces additional loading on occupant. Signs of belt loading are more obvious in high-speed frontal collisions with heavy occupants. However subtle changes may occur at low speeds or with low forces from occupants during rollovers. In certain cases, the seat belt webbing is twisted and loaded by the occupant. The loading of webbing induces an observable fold/crimp on the seat belt. The purpose of the study is to biomechanically evaluate the force required to produce such marks using an anthropometric physical test dummy. Two tests were conducted to determine the amount of force required to put an observable fold/crimp in a shoulder belt. A head form designed by Voight Hodgson was used to represent the neck which interacted with the belt. The force was applied with a pneumatic pull ram (central hydraulic 89182 N) and the force was measured with a 44,000 N transducer load cell (DSM-10K). Results indicate that the force of over 1,000 N produced a fold or crimp in the belt.

  17. Physiological and biomechanical aspects of orienteering.

    Science.gov (United States)

    Creagh, U; Reilly, T

    1997-12-01

    Orienteering is an endurance running event which differs from other running sports both in its cognitive element and in the type of terrain encountered. The demands of overcoming this terrain are not manifest in significant differences between orienteers and road runners in somatotype, though elite female orienteers have consistently been shown to have higher levels of adiposity (> 19%) than elite road runners. High aerobic power in orienteers (up to 63 and 76 ml/kg/min in women and men, respectively) is coupled with lower anaerobic performance. While leg strength is generally not high when compared with other athletic specialties, female orienteers have relatively good leg flexion strength. The energy cost of running is greatly increased in rough terrain. Oxygen cost was 26% higher while running in a forest when compared with road running. Biomechanical differences in stride pattern contribute towards this increased demand. Despite the high energy demands during competition, orienteers pace themselves such that their mean heart rate remains within the range of 167 to 172 beats/min, despite large fluctuations. The rough terrain encountered in orienteering results not only in a high energy cost but also in a higher incidence of sport-specific injuries, particularly to the ankle. Minor injuries such as cuts and bruises are common during competition.

  18. Biomechanics of fencing sport: A scoping review

    Science.gov (United States)

    Chen, Tony Lin-Wei; Wong, Duo Wai-Chi; Wang, Yan; Ren, Sicong; Yan, Fei

    2017-01-01

    Objectives The aim of our scoping review was to identify and summarize current evidence on the biomechanics of fencing to inform athlete development and injury prevention. Design Scoping review. Method Peer-reviewed research was identified from electronic databases using a structured keyword search. Details regarding experimental design, study group characteristics and measured outcomes were extracted from retrieved studies, summarized and information regrouped under themes for analysis. The methodological quality of the evidence was evaluated. Results Thirty-seven peer-reviewed studies were retrieved, the majority being observational studies conducted with experienced and elite athletes. The methodological quality of the evidence was “fair” due to the limited scope of research. Male fencers were the prevalent group studied, with the lunge and use of a foil weapon being the principal movement evaluated. Motion capture and pedabarography were the most frequently used data collection techniques. Conclusions Elite fencers exhibited sequential coordination of upper and lower limb movements with coherent patterns of muscle activation, compared to novice fencers. These elite features of neuromuscular coordination resulted in higher magnitudes of forward linear velocity of the body center of mass and weapon. Training should focus on explosive power. Sex- and equipment-specific effects could not be evaluated based on available research. PMID:28187164

  19. Biomechanics during exercise with a novel stairclimber.

    Science.gov (United States)

    Tsai, Y-J; Hsue, B-J; Lin, C-J; Su, F-C

    2011-09-01

    The current study aimed to investigate the stair-climbing biomechanics related to the lower extremities when subjects used the novel designed stair-climber, which could provide opportunity for both sagittal and frontal movements. 12 volunteers were required to step while either keeping the trunk static (STATIC) or allowing the trunk to shift with weight bearing (SHIFT). A motion analysis system and the 6-axis force and torque sensor embedded in the pedal were used to collect data. Foot contact forces and joint moments were calculated to represent loading characteristics. The joint angle and corresponding moments at the terminal point of the stance phase were computed to serve as the indicator of safety. Significant differences were found in peak foot contact forces, knee extensor moment, and hip abductor moment. At the end of the stance phase, various directions of moment between conditions were found in the knee and the ankle. The knee valgus angle, hip abductor moment, and knee extensor moment were significantly greater in SHIFT than in STATIC. The various stepping strategies caused differences in joint loading characteristics; therefore, these findings need to be given greater consideration in the design of training protocols.

  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. 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.

  2. 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.

  3. 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.

  4. [Hernia surgery in urology: part 1: inguinal, femoral and umbilical hernias - fundamentals of clinical diagnostics and treatment].

    Science.gov (United States)

    Franz, T; Schwalenberg, T; Dietrich, A; Müller, J; Stolzenburg, J-U

    2013-05-01

    Hernias are a common occurrence with correspondingly huge clinical and economic impacts on the healthcare system. The most common forms of hernia which need to be diagnosed and treated in routine urological work are inguinal and umbilical hernias. With the objective of reconstructing and stabilizing the inguinal canal there are the possibilities of open and minimally invasive surgery and both methods can be performed with suture or mesh repair. Indications for surgery of umbilical hernias are infrequent although this is possible with little effort under local anesthesia. This article presents an overview of the epidemiology, pathogenesis, clinical symptoms, diagnostics and therapy of inguinal, femoral and umbilical hernias.

  5. [Ulcerative colitis and Crohn's disease. Part 1. Definition, terminology, prevalence, etiology and patogenesis, clinical features, complications, classification].

    Science.gov (United States)

    Tsimmerman, Ia S; Tsimmerman, I Ia; Tret'iakova, Iu I

    2013-01-01

    Definitions of ulcerative colitis (UC) and Crohn's disease (CD) are given, related terminological problems are discussed, the prevalence of UC and CD in the population is considered along with their etiology pathogenesis, clinical symptoms, complications and extraintestinal (systemic) lesions. Classification and diagnostics of UC and CD are discussed with special reference to current international recommendations on their diagnostics and differential treatment.

  6. Development of a Dynamic Biomechanical Model for Load Carriage: Phase 1 Part A: Equipment Upgrades to Accommodate Dynamic Biomechanical Modeling

    Science.gov (United States)

    2005-08-01

    mannequin. For the first objective, a combination of MatLab (a numerical computation and data visualization program) and Microsoft Excel macros was...modifications bidimensionnelles ont été apportées à l’appareil; la fonction tridimensionnelle sera ajoutée plus tard. Les changements apportés au...système automatisé programmable de commande des mouvements ont donné accès à des fonctions qui n’existaient pas dans le système précédent, notamment : 1

  7. 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.

  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. Histopathological and biomechanical evaluation of tenocyte seeded allografts on rat Achilles tendon regeneration.

    Science.gov (United States)

    Güngörmüş, Cansın; Kolankaya, Dürdane; Aydin, Erkin

    2015-05-01

    Tendon injuries in humans as well as in animals' veterinary medicine are problematic because tendon has poor regenerative capacity and complete regeneration of the ruptured tendon is never achieved. In the last decade there has been an increasing need of treatment methods with different approaches. The aim of the current study was to improve the regeneration process of rat Achilles tendon with tenocyte seeded decellularized tendon matrices. For this purpose, Achilles tendons were harvested, decellularized and seeded as a mixture of three consecutive passages of tenocytes at a density of 1 × 10(6) cells/ml. Specifically, cells with different passage numbers were compared with respect to growth characteristics, cellular senescence and collagen/tenocyte marker production before seeding process. The viability of reseeded tendon constructs was followed postoperatively up to 6 months in rat Achilles tendon by histopathological and biomechanical analysis. Our results suggests that tenocyte seeded decellularized tendon matrix can significantly improve the histological and biomechanical properties of tendon repair tissue without causing adverse immune reactions. To the best of our knowledge, this is the first long-term study in the literature which was accomplished to prove the use of decellularized matrix in a clinically relevant model of rat Achilles tendon and the method suggested herein might have important implications for translation into the clinic.

  10. Biomechanics Strategies for Space Closure in Deep Overbite

    Directory of Open Access Journals (Sweden)

    Harryanto Wijaya

    2013-07-01

    Full Text Available Space closure is an interesting aspect of orthodontic treatment related to principles of biomechanics. It should be tailored individually based on patient’s diagnosis and treatment plan. Understanding the space closure biomechanics basis leads to achieve the desired treatment objective. Overbite deepening and losing posterior anchorage are the two most common unwanted side effects in space closure. Conventionally, correction of overbite must be done before space closure resulted in longer treatment. Application of proper space closure biomechanics strategies is necessary to achieve the desired treatment outcome. This cases report aimed to show the space closure biomechanics strategies that effectively control the overbite as well as posterior anchorage in deep overbite patients without increasing treatment time. Two patients who presented with class II division 1 malocclusion were treated with fixed orthodontic appliance. The primary strategies included extraction space closure on segmented arch that employed two-step space closure, namely single canine retraction simultaneously with incisors intrusion followed by enmasse retraction of four incisors by using differential moment concept. These strategies successfully closed the space, corrected deep overbite and controlled posterior anchorage simultaneously so that the treatment time was shortened. Biomechanics strategies that utilized were effective to achieve the desired treatment outcome.

  11. A new methodology to measure the running biomechanics of amputees.

    Science.gov (United States)

    Wilson, James Richard; Asfour, Shihab; Abdelrahman, Khaled Zakaria; Gailey, Robert

    2009-09-01

    We present a new methodology to measure the running biomechanics of amputees. This methodology combines the use of a spring-mass model and symmetry index, two standard techniques in biomechanics literature, but not yet used in concert to evaluate amputee biomechanics. The methodology was examined in the context of a pilot study to examine two transtibial amputee sprinters and showed biomechanically quantifiable changes for small adjustments in prosthetic prescription. Vertical ground reaction forces were measured in several trials for two transtibial amputees running at constant speed. A spring-mass model was used in conjunction with a symmetry index to observe the effect of varying prosthetic height and stiffness on running biomechanics. All spring-mass variables were significantly affected by changes in prosthetic prescription among the two subjects tested (p < 0.05). When prosthetic height was changed, both subjects showed significant differences, in Deltay(max), Deltal and contact time (t(c)) on the prosthetic limb and in k(vert) and k(leg) on the sound limb. The symmetry indices calculated for spring-mass variables were all significantly affected due to changes in prosthetic prescription for the male subject and all but the peak force (F(peak)) for the female subject. This methodology is a straight-forward tool for evaluating the effect of changes to prosthetic prescription.

  12. 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

  13. State-of-the-art research in lower-limb prosthetic biomechanics-socket interface: a review.

    Science.gov (United States)

    Mak, A F; Zhang, M; Boone, D A

    2001-01-01

    Scientific studies have been conducted to quantify attributes that may be important in the creation of more functional and comfortable lower-limb prostheses. The prosthesis socket, a human-machine interface, has to be designed properly to achieve satisfactory load transmission, stability, and efficient control for mobility. The biomechanical understanding of the interaction between prosthetic socket and the residual limb is fundamental to such goals. The purpose of this paper is to review the recent research literature on socket biomechanics, including socket pressure measurement, friction-related phenomena and associated properties, computational modeling, and limb tissue responses to external mechanical loads and other physical conditions at the interface. There is no doubt that improved biomechanical understanding has advanced the science of socket fitting. However, the most recent advances in the understanding of stresses experienced at the residual limb have not yet led to enough clinical consensus that could fundamentally alter clinical practice. Efforts should be made to systematically identify the major discrepancies. Further research should be directed to address the critical controversies and the associated technical challenges. Developments should be guided to offer clinicians the quantification and visualization of the interaction between the residual limb and the prosthetic socket. An understanding of comfort and optimal load transfer as patterns of socket interface stress could culminate in socket design expert systems.

  14. 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

  15. 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

  16. Hangman's fracture: a historical and biomechanical perspective.

    Science.gov (United States)

    Rayes, Mahmoud; Mittal, Monika; Rengachary, Setti S; Mittal, Sandeep

    2011-02-01

    The execution technique of hanging, introduced by the Angle, Saxon, and Jute Germanic tribes during their invasions of the Roman Empire and Britain in the 5th century, has remained largely unchanged over time. The earliest form of a gallows was a tree on which prisoners were hanged. Despite the introduction of several modifications such as a trap door, the main mechanism of death remained asphyxiation. This created the opportunity for attempted revival after the execution, and indeed several well-known cases of survival following judicial hanging have been reported. It was not until the introduction of the standard drop by Dr. Samuel Haughton in 1866, and the so-called long drop by William Marwood in 1872 that hanging became a standard, humane means to achieve instantaneous death. Hangmen, however, fearing knot slippage, started substituting the subaural knot for the traditional submental knot. Subaural knots were not as effective, and cases of decapitation were recorded. Standardization of the long drop was further propagated by John Berry, an executioner who used mathematical calculations to estimate the correct drop length for each individual to be hanged. A British committee on capital sentences, led by Lord Aberdare, studied the execution method, and advocated for the submental knot. However, it was not until Frederic Wood-Jones published his seminal work in 1913 that cervical fractures were identified as the main mechanism of death following hanging in which the long drop and a submental knot were used. Schneider introduced the term "hangman's fracture" in 1965, and reported on the biomechanics and other similarities of the cervical fractures seen following judicial hangings and those caused by motor vehicle accidents.

  17. THE APPROACH OF CANCER RELATED FATIGUE IN RHEABILITATION MEDICINE: PART I – MECHANISMS, SYMPTOMS, CLINICAL EVALUATION AND SCREENING

    Directory of Open Access Journals (Sweden)

    SALCA Amalia

    2015-05-01

    Full Text Available Cancer related fatigue (CRF is the most disabling and distressing symptom in cancer, throughout the whole history of the illness, including successfully treated cases. Rehabilitation medicine could have a positive impact on these patients’ outcomes, if well targeted. With these purpose, the rehabilitation clinician needs to correctly assess fatigue using standard, reliable scales. This review of articles and trials synthesizes the epidemiology, mechanics (including causes and effects, clinical presentation and means of assessment in CRF. CRF causes and mechanisms are not well known. Understanding them would provide specific targets to fatigue management. Clinical presentation is very variable, a wide range of features being found in literature. Poorly medical reports in assessing fatigue offer variable percentages of prevalence, inconsistent with patients’ daily burden due to CRF. There are many tools used to assess fatigue in clinical research and on them depends the percentages reported as fatigue prevalence. The hereby gathered information are useful in the approach of a patient that addresses to a rehabilitation clinician for CRF management.

  18. 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.

  19. Adolescent baseball pitching technique: lower extremity biomechanical analysis.

    Science.gov (United States)

    Milewski, Matthew D; Õunpuu, Sylvia; Solomito, Matthew; Westwell, Melany; Nissen, Carl W

    2012-11-01

    Documentation of the lower extremity motion patterns of adolescent pitchers is an important part of understanding the pitching motion and the implication of lower extremity technique on upper extremity loads, injury and performance. The purpose of this study was to take the initial step in this process by documenting the biomechanics of the lower extremities during the pitching cycle in adolescent pitchers and to compare these findings with the published data for older pitchers. Three-dimensional motion analysis using a comprehensive lower extremity model was used to evaluate the fast ball pitch technique in adolescent pitchers. Thirty-two pitchers with a mean age of 12.4 years (range 10.5-14.7 years) and at least 2 years of experience were included in this study. The pitchers showed a mean of 49 ± 12° of knee flexion of the lead leg at foot contact. They tended to maintain this position through ball release, and then extended their knee during the follow through phase (ball release to maximal internal glenohumeral rotation). The lead leg hip rapidly progressed into adduction and flexion during the arm cocking phase with a range of motion of 40 ± 10° adduction and 30 ± 13° flexion. The lead hip mean peak adduction velocity was 434 ± 83°/s and flexion velocity was 456 ± 156°/s. Simultaneously, the trailing leg hip rapidly extended approaching to a mean peak extension of -8 ± 5° at 39% of the pitch cycle, which is close to passive range of motion constraints. Peak hip abduction of the trailing leg at foot contact was -31 ± 12°, which also approached passive range of motion constraints. Differences and similarities were also noted between the adolescent lower extremity kinematics and adult pitchers; however, a more comprehensive analysis using similar methods is needed for a complete comparison.

  20. [Biomechanical aspects of the claw-floor interaction in dairy cattle: implications for locomotion and claw disorders].

    Science.gov (United States)

    van der Tol, P P J

    2004-07-01

    The prevalence of claw disorders is still high among cows housed on concrete floors. Concrete floors affect the locomotion of cattle, their natural behavior. Although many factors affect the development of claw disorders and locomotor problems, biomechanical aspects have hardly been analysed. In this thesis, mechanical (over)loading of the claw and its significance for claw disorders and lameness are discussed. The mechanical characteristics a floor needs to provide in order to enable unrestrained locomotory behavior. This biomechanical approach, which is a relatively new approach in cattle locomotion, has provided new insights. Despite preventive trimming, the weakest parts of the claw capsule are loaded relatively the most. Concrete floors provide too little friction to enable unrestricted cattle locomotion.

  1. Foot orthoses improve kinematic measurement in young women with biomechanical abnormality

    Directory of Open Access Journals (Sweden)

    Maria Regina Rachmawati

    2015-12-01

    Foot pronation causes biomechanical abnormalities in the form of functional leg-length disparity. Foot orthoses are often used in the treatment of abnormal pronation. The aim of the study was to evaluate the effect of foot orthoses on abnormal kinematic chain the differences of pelvic height, step length, and walking distance on walking test in young women with biomechanical abnormality. METHODS A randomized double blind controlled clinical trial was conducted on 27 young adult women having abnormal biomechanical abnormalities. By random allocation the subjects were divided into the intervention group (14 subjects receiving correction of foot pronation using foot orthoses, and the control group (13 subjects receiving no orthoses. Before and during use of foot orthoses, we determined pelvic height difference (mm, step length difference (cm, and walking distance at maximal walking speed for 15 minutes. RESULTS Correction of foot pronation resulted in decreased pelvic height difference from 4.7 ± 2.1 mm to 1.7 ± 1.3 mm (p<0.001 and in a reduction in step length difference, from 4.9 ± 2.9 cm to 2.1 ± 1.5 cm (p=0.002. Walking test distance of the intervention group was 1318.5 ± 46.3 m, as compared with that of the control group of 1233 ± 114.7 m (p = 0.05. Walking distance of the intervention group rose steadily in the second test to 1369.3 ± 27 m, and in the third test to 1382.14 ± 10.5 m (p<0.001. CONCLUSIONS Foot orthoses improved the kinematic chain, resulting in a more symmetrical pelvic height, reduced step length difference, and increased functional walking ability.

  2. Biomechanical properties of bone in a mouse model of Rett syndrome.

    Science.gov (United States)

    Kamal, Bushra; Russell, David; Payne, Anthony; Constante, Diogo; Tanner, K Elizabeth; Isaksson, Hanna; Mathavan, Neashan; Cobb, Stuart R

    2015-02-01

    Rett syndrome (RTT) is an X-linked genetic disorder and a major cause of intellectual disability in girls. Mutations in the methyl-CpG binding protein 2 (MECP2) gene are the primary cause of the disorder. Despite the dominant neurological phenotypes, MECP2 is expressed ubiquitously throughout the body and a number of peripheral phenotypes such as scoliosis, reduced bone mineral density and skeletal fractures are also common and important clinical features of the disorder. In order to explore whether MeCP2 protein deficiency results in altered structural and functional properties of bone and to test the potential reversibility of any defects, we have conducted a series of histological, imaging and biomechanical tests of bone in a functional knockout mouse model of RTT. Both hemizygous Mecp2(stop/y) male mice in which Mecp2 is silenced in all cells and female Mecp2(stop/+) mice in which Mecp2 is silenced in ~50% of cells as a consequence of random X-chromosome inactivation, revealed significant reductions in cortical bone stiffness, microhardness and tensile modulus. Microstructural analysis also revealed alterations in both cortical and cancellous femoral bone between wild-type and MeCP2-deficient mice. Furthermore, unsilencing of Mecp2 in adult mice cre-mediated stop cassette deletion resulted in a restoration of biomechanical properties (stiffness, microhardness) towards wild-type levels. These results show that MeCP2-deficiency results in overt, but potentially reversible, alterations in the biomechanical integrity of bone and highlights the importance of targeting skeletal phenotypes in considering the development of pharmacological and gene-based therapies.

  3. 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.

  4. 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...

  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. 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.

  7. Biomechanically Excited SMD Model of a Walking Pedestrian

    DEFF Research Database (Denmark)

    Zhang, Mengshi; Georgakis, Christos T.; Chen, Jun

    2016-01-01

    estimated from a known walking frequency and the pedestrian's weight, assuming that pedestrians always walk in displacement resonance and retain a constant damping ratio of 0.3. Thus, biomechanical forces were extracted using the measured SMD dynamic responses and the estimated SMD parameters. Extracted...... of biomechanical forces, was used to model a pedestrian for application in vertical human-structure interaction (HSI). Tests were undertaken in a gait laboratory, where a three-dimensional motion-capture system was used to record a pedestrian's walking motions at various frequencies. The motion-capture system...... produced the pedestrian's center of mass (COM) trajectories from the captured motion markers. The vertical COM trajectory was approximated to be the pedestrian SMD dynamic responses under the excitation of biomechanical forces. SMD model parameters of a pedestrian for a specific walking frequency were...

  8. 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 ...

  9. Vertical Jump Biomechanics Altered With Virtual Overhead Goal.

    Science.gov (United States)

    Ford, Kevin R; Nguyen, Anh-Dung; Hegedus, Eric J; Taylor, Jeffrey B

    2017-04-01

    Virtual environments with real-time feedback can simulate extrinsic goals that mimic real life conditions. The purpose was to compare jump performance and biomechanics with a physical overhead goal (POG) and with a virtual overhead goal (VOG). Fourteen female subjects participated (age: 18.8 ± 1.1 years, height: 163.2 ± 8.1 cm, weight 63.0 ± 7.9 kg). Sagittal plane trunk, hip, and knee biomechanics were calculated during the landing and take-off phases of drop vertical jump with different goal conditions. Repeated-measures ANOVAs determined differences between goal conditions. Vertical jump height displacement was not different during VOG compared with POG. Greater hip extensor moment (P biomechanical testing, screening, and training conditions.

  10. [Air transport biomechanical risk: reduced mobility passengers' handling].

    Science.gov (United States)

    Draicchio, F; Campoli, G; Silvetti, A; Badellino, E; Forzano, F; Ranavolo, A; Iavicoli, S; Campagna, G; Raffaele, G; Gismondi, M

    2012-01-01

    As the airport traffic increases there is a continuous increase of passengers with different motor disabilities. Disabled passenger's assistance causes a biomechanical overload in airport workers. Some disabled passengers are classified by IATA as WCHC (wheel chair in cabin or Charlie). Our study, was performed in one of the most important Italian airport on Charlie passengers (about 10% of all assistances). We identified four critical points: 1) wheelchair and baggage moving (unstable load), 2) inclined ramps with worker's backwards steps and braked wheelchair to prevent passenger tipping or falling, 3) transfer from standard wheelchair to bicycle wheelchair, specifically designed for the aisle; 4.) transfer from bicycle wheelchair to aircraft seat. The last two points required sometimes to lift passengers over the armrest and positioning them on a window side seat, causing a serious increase of biomechanical load. For each critical point we have proposed technical and organizational measures to reduce airport worker's biomechanical risk.

  11. 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.

  12. Influence of locomotion speed on biomechanical subtask and muscle synergy.

    Science.gov (United States)

    Gui, Kai; Zhang, Dingguo

    2016-10-01

    This paper investigates the relationship of biomechanical subtasks, and muscle synergies with various locomotion speeds. Ground reaction force (GRF) of eight healthy subjects is measured synchronously by force plates of treadmill at five different speeds ranging from 0.5m/s to 1.5m/s. Four basic biomechanical subtasks, body support, propulsion, swing, and heel strike preparation, are identified according to GRF. Meanwhile, electromyography (EMG) data, used to extract muscle synergies, are collected from lower limb muscles. EMG signals are segmented periodically based on GRF with the heel strike as the split points. Variability accounted for (VAF) is applied to determine the number of muscle synergies. We find that four muscle synergies can be extracted in all five situations by non-negative matrix factorization (NMF). Furthermore, the four muscle synergies and biomechanical subtasks keep invariant as the walking speed changes.

  13. The Experimental Research Development of Foot Biomechanics%足部生物力学实验研究进展

    Institute of Scientific and Technical Information of China (English)

    杨琳; 梁栋柱

    2011-01-01

    The human plantar pressure measurement, gait analysis and digital modeling of human foot are three important aspects in biomechanical study of foot,there are some effective supports for the basic study of foot diseases and functional rehabilitation. In this paper,the three applied technology in the study of foot biomechanics characteristics and perspective were described from the basic researches, clinical applications and rehabilitation of foot function. According to the anatomic characteristics and biomechanical mechanisms of common foot disorders,the clinical application and market demand of foot biomechanics are reviewed by the foot functional rehabilitation research and further promising studies are proposed.%人体足底压力测量、步态分析及足数字模型是目前足部生物力学研究的热点,为足部疾病基础研究和康复功能研究提供了有效的支持.现从基础研究、临床应用及足部功能康复角度出发,对上述三种应用技术在足部生物力学研究中的应用作出总结.根据临床常见足部疾病的解剖学特点与生物力学机制,在足部功能康复领域对足部生物力学在临床与市场需求的应用展开论述,并对今后的研究工作提出展望.

  14. 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...

  15. 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,…

  16. [Treatment with charged particles beams: hadrontherapy part I: physical basis and clinical experience of treatment with protons].

    Science.gov (United States)

    Noël, G; Feuvret, L; Ferrand, R; Mazeron, J-J

    2003-10-01

    Protons have physical characteristics, which differ from those of photons used in conventional radiotherapy. Better shielding of critical organs is obtained by using their particular ballistic (Bragg peak and lateral narrow penumbra). Some indications as ocular melanoma, chordoma and chondrosarcoma of the base of skull are now strongly accepted by the radiation oncologist community. Others are still in evaluation: meningioma, locally advanced nasopharynx tumor and paediatric tumors. The aim of this review is to present the clinical results of a technic which seems "confidential" because of the rarety and the cost of equipments.

  17. 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...

  18. 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.

  19. Biomechanical Response and Behavior of Users under Emergency Buffer Crash

    Directory of Open Access Journals (Sweden)

    R. Miralbes

    2013-01-01

    Full Text Available This paper aims to study the biomechanical effects on elevator users and the injuries sustained should an elevator crash happen. The analysis will focus on buffer impact, signaling that the earlier mentioned buffer is usually located at the bottom of the pit. In order to carry out this analysis, a numerical technique based on finite element method will be used, while elevator users will be simulated by means of automotive dummies. Two crash factors will be studied, namely, location of dummy and fall velocity. The analysis criteria will be damages sustained by the dummy, based on biomechanical index such as HIC, CSI, forces, and accelerations.

  20. [Trauma and psychosis--part 1. On the association of early childhood maltreatment in clinical populations with psychotic disorders].

    Science.gov (United States)

    Kapfhammer, Hans-Peter

    2012-01-01

    A comprehensive literature stresses a high percentage of severe childhood maltreatment in the history of many psychotically ill patients treated in mental health services. Early childhood abuse seems to be associated among other things with a more severe clinical state, a more chronic course of illness and a more unfavourable psychosocial adaptation. In order not to jump to unwarranted causal conclusions, several conceptual und methodological problems have to be clarified before. From a conceptual perspective psychotic disorders diagnosed according to conventional criteria define only a minor subgroup within a much broader psychosis continuum in general population. Early childhood abuse has to be differentiated according to type, severity, timing, and context. The rates of early childhood abuse are high in general population. The methods of measurement of psychotic symptoms on the one side, of early trauma on the other side have to be critically evaluated. There is an empirically well founded association of childhood maltreatment and psychological and psychosomatic morbidity during adult years in general. In order to establish a potential conditional link also to psychotic disorders, clinical populations have to be compared to adequate control groups at least. A systematic literature search shows a very small number of studies including control groups at all. These studies underline that early childhood abuse may be significantly associated to the risk of psychosis indeed. The conditional role of early childhood abuse, however, has to be investigated only within a multifactorial biopsychosocial model of psychotic illness.

  1. REAL TIME PCR IDENTIFICATION FOR TARGET ADJUNCTIVE ANTIBIOTIC THERAPY OF SEVERE CHRONIC PERIODONTITIS. PART I - CLINICAL RESULTS.

    Directory of Open Access Journals (Sweden)

    Kamen Kotsilkov

    2014-10-01

    Full Text Available INTRODUCTION: The periodontal pathology is of great social importance due to the vast distribution in the human population. The adjunctive antibiotic administration could improve the healing in such cases but the latest data of the continuingly growing antibiotic resistance requires more precise approaches of antibiotic selection. The contemporary molecular diagnostic methods could offer the required precision for the microbiological identification in order to achieve better control of the periodontitis. OBJECTIVE: The aim of this study is to compare the microbiological effectiveness of adjunctive antibiotic administration with the mechanical periodontal therapy. METHODS: 30 patients with severe chronic periodontitis were enrolled in this study and were divided in 3 groups: Control group – with mechanical debridement only. Test group 1 – with combined adjunctive antibiotic administration using Amoxicillin+ Metronidazole. Test group 2 – with target antibiotic administration according to the resuts from the Real Time PCR identification. RESULTS: A considerable improvement of the periodontal status was reported in all treatment groups. The most positive results were in the group with target antibiotic administration were all tested clinical parameters showed the best improvement with statistically significant changes in sites with PD7mm and CAL>5mm. CONCLUSION: The adjunctive antibiotic administration demonstrates better clinical effectiveness concerning the reduction of the severely affected sites in cases with severe generalized chronic periodontitis compared to the mechanical therapy alone. From all examined groups the target approach has statistically significant better results. These results suggest that this approach is recommended in cases with high prevalence of deep pockets.

  2. MR elastography to measure the effects of cancer and pathology fixation on prostate biomechanics, and comparison with T 1, T 2 and ADC

    Science.gov (United States)

    McGrath, Deirdre M.; Lee, Jenny; Foltz, Warren D.; Samavati, Navid; van der Kwast, Theo; Jewett, Michael A. S.; Chung, Peter; Ménard, Cynthia; Brock, Kristy K.

    2017-02-01

    MRI is under evaluation for image-guided intervention for prostate cancer. The sensitivity and specificity of MRI parameters is determined via correlation with the gold-standard of histopathology. Whole-mount histopathology of prostatectomy specimens can be digitally registered to in vivo imaging for correlation. When biomechanical-based deformable registration is employed to account for deformation during histopathology processing, the ex vivo biomechanical properties are required. However, these properties are altered by pathology fixation, and vary with disease. Hence, this study employs magnetic resonance elastography (MRE) to measure ex vivo prostate biomechanical properties before and after fixation. A quasi-static MRE method was employed to measure high resolution maps of Young’s modulus (E) before and after fixation of canine prostate and prostatectomy specimens (n  =  4) from prostate cancer patients who had previously received radiation therapy. For comparison, T 1, T 2 and apparent diffusion coefficient (ADC) were measured in parallel. E (kPa) varied across clinical anatomy and for histopathology-identified tumor: peripheral zone: 99(±22), central gland: 48(±37), tumor: 85(±53), and increased consistently with fixation (factor of 11  ±  5 p  biomechanics of the clinical prostate specimens varied greatly with fixation, and to a lesser extent with disease and anatomy. The data obtained will improve the precision of prostate pathology correlation, leading to more accurate disease detection and targeting.

  3. Clinical trial design principles and endpoint definitions for transcatheter mitral valve repair and replacement: part 2: endpoint definitions: A consensus document from the Mitral Valve Academic Research Consortium.

    Science.gov (United States)

    Stone, Gregg W; Adams, David H; Abraham, William T; Kappetein, Arie Pieter; Généreux, Philippe; Vranckx, Pascal; Mehran, Roxana; Kuck, Karl-Heinz; Leon, Martin B; Piazza, Nicolo; Head, Stuart J; Filippatos, Gerasimos; Vahanian, Alec S

    2015-08-01

    Mitral regurgitation (MR) is one of the most prevalent valve disorders and has numerous aetiologies, including primary (organic) MR, due to underlying degenerative/structural mitral valve (MV) pathology, and secondary (functional) MR, which is principally caused by global or regional left ventricular remodelling and/or severe left atrial dilation. Diagnosis and optimal management of MR requires integration of valve disease and heart failure specialists, MV cardiac surgeons, interventional cardiologists with expertise in structural heart disease, and imaging experts. The introduction of trans- catheter MV therapies has highlighted the need for a consensus approach to pragmatic clinical trial design and uniform endpoint definitions to evaluate outcomes in patients with MR. The Mitral Valve Academic Research Consortium is a collaboration between leading academic research organizations and physician-scientists specializing in MV disease from the United States and Europe. Three in-person meetings were held in Virginia and New York during which 44 heart failure, valve, and imaging experts, MV surgeons and interventional cardiologists, clinical trial specialists and statisticians, and representatives from the U.S. Food and Drug Administration considered all aspects of MV pathophysiology, prognosis, and therapies, culminating in a 2-part document describing consensus recommendations for clinical trial design (Part 1) and endpoint definitions (Part 2) to guide evaluation of transcatheter and surgical therapies for MR. The adoption of these recommendations will afford robustness and consistency in the comparative effectiveness evaluation of new devices and approaches to treat MR. These principles may be useful for regulatory assessment of new transcatheter MV devices, as well as for monitoring local and regional outcomes to guide quality improvement initiatives.

  4. 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.

  5. 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.

  6. 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.

  7. A closer look at diagnosis in clinical dental practice: part 5. Emerging technologies for caries detection and diagnosis.

    Science.gov (United States)

    Pretty, Iain A; Maupomé, Gerardo

    2004-09-01

    Parts 5 and 6 of this series examine innovations in diagnostic and management procedures and assess their potential to become everyday tools of the dental clinician. This paper examines some of the diagnostic tools supporting a philosophical shift in mainstream dental practice from concern with extensively decayed teeth to a focus on detecting incipient demineralized tissues. With the latter approach, the incipient carious process can be reversed by promoting enamel remineralization and thus eliminating the need for restorative intervention. Numerous methods and devices have been developed to detect, diagnose and monitor such lesions, and several have been produced in versions that may appeal to dental practitioners. This paper considers 3 of these methods and devices: the DIAGNODent laser device, quantitative light-induced fluorescence and the Digital Imaging Fiber-Optic Transillumination device. Each technique is illustrated, the research on its effectiveness is assessed to determine usefulness to the practitioner, and the comparative advantages of the 3 adjunct tools are discussed.

  8. Biomechanical evaluation of an interfacet joint decompression and stabilization system.

    Science.gov (United States)

    Leasure, Jeremi M; Buckley, Jenni

    2014-07-01

    -alone minimally invasive technologies. The FJ spacer system effectively increased stiffness of the affected level comparable to predicate systems. Results of this study indicate the FJ spacer increases foraminal area in the cervical spine, and decompression is maintained during bending activities. Clinical studies will be necessary to determine whether the magnitude of decompression observed in this cadaveric study will effectively treat cervical radiculopathy; however, results of this study, taken in context of successful decompression treatments in the lumbar spine, are promising for the continued development of this product. Results of this biomechanical study are encouraging for the continued investigation of this device in animal and clinical trials, as they suggest the device is well fixated and mechanically competent.

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

    Energy Technology Data Exchange (ETDEWEB)

    Beltran-Fernandez, J A; Hernandez-Gomez, L H; Ruiz-Munoz, E; Urriolagoitia-Calderon, G; Urriolagoitia-Sosa, G [Escuela Superior de IngenierIa Mecanica y Electrica (ESIME) Unidad Zacatenco, Edificio 5, 3er Piso, 07738, D.F., Mexico, Tel.: 52(55)57296000, ext. 54691 (Mexico); Gonzalez-Rebattu, A [Hospital Regional ISSSTE 10 de Octubre, Av. Instituto Politecnico Nacional, Num. 1669, Col. Magdalena de las Salinas, 07760 (Mexico); RodrIguez-Canizo, R G [Escuela Superior de IngenierIa Mecanica y Electrica (ESIME) Unidad Azcapotzalco, Av. Granjas No. 682 Col. Sta. Catarina, 02550 (Mexico); Hernandez-Moreno, H, E-mail: jbeltran@ipn.m, E-mail: luishector56@hotmail.co, E-mail: edrm_ipn@hotmail.co, E-mail: janosclub@hotmail.co, E-mail: ricname@hotmail.co, E-mail: guiurri@hotmail.co, E-mail: hihernandezm@ipn.m

    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.

  10. Modified stabilization method for the tibial tuberosity advancement technique: a biomechanical study

    Directory of Open Access Journals (Sweden)

    Bruno Testoni Lins

    Full Text Available The present study aimed to determine biomechanical alterations resultant from a modification in the fixation method of the tibial tuberosity advancement technique (TTA, originally described for stabilization of the cranial cruciate-deficient stifle. Ten adult mongrel dogs weighing 25-30kg were used. After euthanasia, performed for reasons unrelated to this study, the hind limbs were distributed into two groups: G1 operated (n=10 and G2 control (n=10, represented by the contralateral limb. The operated hind limbs were orthopedically, goniometrically and radiographically evaluated, sequentially at four moments: moment 1, in intact joints; moment 2, after cranial cruciate desmotomy; moment 3, after surgical stabilization of the stifle joint using modified TTA; and moment 4, after caudal cruciate ligament desmotomy. The tibial tuberosity was stabilized by one shaft screw craniocaudally and a titanium cage inserted at the osteotomy site. The position of the patellar tendon at 90° in relation to the tibial plateau allowed cranial tibial thrust force neutralization, despite cranial drawer motion maintenance in all dogs. The biomechanical tests confirm the viability of the tibial tuberosity fixation method and support future clinical trials to validate the technique.

  11. Do design variations in the artificial disc influence cervical spine biomechanics? A finite element investigation.

    Science.gov (United States)

    Faizan, Ahmad; Goel, Vijay K; Garfin, Steven R; Bono, Christopher M; Serhan, Hassan; Biyani, Ashok; Elgafy, Hossein; Krishna, Manoj; Friesem, Tai

    2012-06-01

    Various ball and socket-type designs of cervical artificial discs are in use or under investigation. Many artificial disc designs claim to restore the normal kinematics of the cervical spine. What differentiates one type of design from another design is currently not well understood. In this study, authors examined various clinically relevant parameters using a finite element model of C3-C7 cervical spine to study the effects of variations of ball and socket disc designs. Four variations of ball and socket-type artificial disc were placed at the C5-C6 level in an experimentally validated finite element model. Biomechanical effects of the shape (oval vs. spherical ball) and location (inferior vs. superior ball) were studied in detail. Range of motion, facet loading, implant stresses and capsule ligament strains were computed to investigate the influence of disc designs on resulting biomechanics. Motions at the implant level tended to increase following disc replacement. No major kinematic differences were observed among the disc designs tested. However, implant stresses were substantially higher in the spherical designs when compared to the oval designs. For both spherical and oval designs, the facet loads were lower for the designs with an inferior ball component. The capsule ligament strains were lower for the oval design with an inferior ball component. Overall, the oval design with an inferior ball component, produced motion, facet loads, implant stresses and capsule ligament strains closest to the intact spine, which may be key to long-term implant survival.

  12. Male and Female Cervical Spine Biomechanics and Anatomy: Implication for Scaling Injury Criteria.

    Science.gov (United States)

    Yoganandan, Narayan; Bass, Cameron R; Voo, Liming; Pintar, Frank A

    2017-05-01

    There is an increased need to develop female-specific injury criteria and anthropomorphic test devices (dummies) for military and automotive environments, especially as women take occupational roles traditionally reserved for men. Although some exhaustive reviews on the biomechanics and injuries of the human spine have appeared in clinical and bioengineering literatures, focus has been largely ignored on the difference between male and female cervical spine responses and characteristics. Current neck injury criteria for automotive dummies for assessing crashworthiness and occupant safety are obtained from animal and human cadaver experiments, computational modeling, and human volunteer studies. They are also used in the military. Since the average human female spines are smaller than average male spines, metrics specific to the female population may be derived using simple geometric scaling, based on the assumption that male and female spines are geometrically scalable. However, as described in this technical brief, studies have shown that the biomechanical responses between males and females do not obey strict geometric similitude. Anatomical differences in terms of the structural component geometry are also different between the two cervical spines. Postural, physiological, and motion responses under automotive scenarios are also different. This technical brief, focused on such nonuniform differences, underscores the need to conduct female spine-specific evaluations/experiments to derive injury criteria for this important group of the population.

  13. The effect of Masai Barefoot Technology (MBT) footwear on lower limb biomechanics: A systematic review.

    Science.gov (United States)

    Tan, Jade M; Auhl, Maria; Menz, Hylton B; Levinger, Pazit; Munteanu, Shannon E

    2016-01-01

    This systematic review evaluated the available evidence for the effects of Masai Barefoot Technology (MBT) footwear on lower limb biomechanics during gait. Electronic databases (MEDLINE, EMBASE, CINAHL, SPORTDiscus, and PubMed) were searched in January 2015. Methodological quality of included studies was evaluated using the Quality Index. Standardised mean differences and 95% confidence intervals were calculated, and meta-analysis was conducted where possible. 17 studies satisfied the inclusion criteria; 16 cross-sectional studies and one randomised control trial (RCT). Quality Index scores ranged from 7 to 12 (out of 15). All 17 studies investigated walking gait only. Evidence showed that MBT footwear caused asymptomatic individuals to walk with a shorter stride length, reduced peak hip flexion, increased peak knee extension, and reduced hip and knee range of motion throughout gait. All kinematic effects occurred in the sagittal plane. There was a trend towards a decrease in internal and external joint moments and power, except for the foot, where increases in force were observed. There were only a small number of changes to lower limb muscle amplitude and timing. No statistically significant effects were observed in symptomatic individuals with knee osteoarthritis or following total knee replacement, but there was an increase in cadence and a decrease in step length in individuals following tibiotalar arthrodesis. These findings suggest that MBT footwear does change lower limb biomechanics in both asymptomatic and symptomatic individuals during gait. However, further clinical trials need to be undertaken to determine whether these changes are therapeutically beneficial.

  14. Cancellous Screws Are Biomechanically Superior to Cortical Screws in Metaphyseal Bone.

    Science.gov (United States)

    Wang, Tim; Boone, Christopher; Behn, Anthony W; Ledesma, Justin B; Bishop, Julius A

    2016-09-01

    Cancellous screws are designed to optimize fixation in metaphyseal bone environments; however, certain clinical situations may require the substitution of cortical screws for use in cancellous bone, such as anatomic constraints, fragment size, or available instrumentation. This study compares the biomechanical properties of commercially available cortical and cancellous screw designs in a synthetic model representing various bone densities. Commercially available, fully threaded, 4.0-mm outer-diameter cortical and cancellous screws were tested in terms of pullout strength and maximum insertion torque in standard-density and osteoporotic cancellous bone models. Pullout strength and maximum insertion torque were both found to be greater for cancellous screws than cortical screws in all synthetic densities tested. The magnitude of difference in pullout strength between cortical and cancellous screws increased with decreasing synthetic bone density. Screw displacement prior to failure and total energy absorbed during pullout strength testing were also significantly greater for cancellous screws in osteoporotic models. Stiffness was greater for cancellous screws in standard and osteoporotic models. Cancellous screws have biomechanical advantages over cortical screws when used in metaphyseal bone, implying the ability to both achieve greater compression and resist displacement at the screw-plate interface. Surgeons should preferentially use cancellous over cortical screws in metaphyseal environments where cortical bone is insufficient for fixation. [Orthopedics.2016; 39(5):e828-e832.].

  15. Effects of antibacterial nanostructured composite films on vascular stents: hemodynamic behaviors, microstructural characteristics, and biomechanical properties.

    Science.gov (United States)

    Cheng, Han-Yi; Hsiao, Wen-Tien; Lin, Li-Hsiang; Hsu, Ya-Ju; Sinrang, Andi Wardihan; Ou, Keng-Liang

    2015-01-01

    The purpose of this research was to investigate stresses resulting from different thicknesses and compositions of hydrogenated Cu-incorporated diamond-like carbon (a-C:H/Cu) films at the interface between vascular stent and the artery using three-dimensional reversed finite element models (FEMs). Blood flow velocity variation in vessels with plaques was examined by angiography, and the a-C:H/Cu films were characterized by transmission electron microscopy to analyze surface morphology. FEMs were constructed using a computer-aided reverse design system, and the effects of antibacterial nanostructured composite films in the stress field were investigated. The maximum stress in the vascular stent occurred at the intersections of net-like structures. Data analysis indicated that the stress decreased by 15% in vascular stents with antibacterial nanostructured composite films compared to the control group, and the stress decreased with increasing film thickness. The present results confirmed that antibacterial nanostructured composite films improve the biomechanical properties of vascular stents and release abnormal stress to prevent restenosis. The results of the present study offer the clinical benefit of inducing superior biomechanical behavior in vascular stents.

  16. 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.

  17. Micro-biomechanics of the Kebara 2 hyoid and its implications for speech in Neanderthals.

    Directory of Open Access Journals (Sweden)

    Ruggero D'Anastasio

    Full Text Available The description of a Neanderthal hyoid from Kebara Cave (Israel in 1989 fuelled scientific debate on the evolution of speech and complex language. Gross anatomy of the Kebara 2 hyoid differs little from that of modern humans. However, whether Homo neanderthalensis could use speech or complex language remains controversial. Similarity in overall shape does not necessarily demonstrate that the Kebara 2 hyoid was used in the same way as that of Homo sapiens. The mechanical performance of whole bones is partly controlled by internal trabecular geometries, regulated by bone-remodelling in response to the forces applied. Here we show that the Neanderthal and modern human hyoids also present very similar internal architectures and micro-biomechanical behaviours. Our study incorporates detailed analysis of histology, meticulous reconstruction of musculature, and computational biomechanical analysis with models incorporating internal micro-geometry. Because internal architecture reflects the loadings to which a bone is routinely subjected, our findings are consistent with a capacity for speech in the Neanderthals.

  18. Micro-biomechanics of the Kebara 2 hyoid and its implications for speech in Neanderthals.

    Science.gov (United States)

    D'Anastasio, Ruggero; Wroe, Stephen; Tuniz, Claudio; Mancini, Lucia; Cesana, Deneb T; Dreossi, Diego; Ravichandiran, Mayoorendra; Attard, Marie; Parr, William C H; Agur, Anne; Capasso, Luigi

    2013-01-01

    The description of a Neanderthal hyoid from Kebara Cave (Israel) in 1989 fuelled scientific debate on the evolution of speech and complex language. Gross anatomy of the Kebara 2 hyoid differs little from that of modern humans. However, whether Homo neanderthalensis could use speech or complex language remains controversial. Similarity in overall shape does not necessarily demonstrate that the Kebara 2 hyoid was used in the same way as that of Homo sapiens. The mechanical performance of whole bones is partly controlled by internal trabecular geometries, regulated by bone-remodelling in response to the forces applied. Here we show that the Neanderthal and modern human hyoids also present very similar internal architectures and micro-biomechanical behaviours. Our study incorporates detailed analysis of histology, meticulous reconstruction of musculature, and computational biomechanical analysis with models incorporating internal micro-geometry. Because internal architecture reflects the loadings to which a bone is routinely subjected, our findings are consistent with a capacity for speech in the Neanderthals.

  19. Edentulism, beaks, and biomechanical innovations in the evolution of theropod dinosaurs.

    Science.gov (United States)

    Lautenschlager, Stephan; Witmer, Lawrence M; Altangerel, Perle; Rayfield, Emily J

    2013-12-17

    Maniraptoriformes, the speciose group of derived theropod dinosaurs that ultimately gave rise to modern birds, display a diverse and remarkable suite of skeletal adaptations. Apart from the evolution of flight, a large-scale change in dietary behavior appears to have been one of the main triggers for specializations in the bauplan of these derived theropods. Among the different skeletal specializations, partial or even complete edentulism and the development of keratinous beaks form a recurring and persistent trend in from the evolution of derived nonavian dinosaurs. Therizinosauria is an enigmatic maniraptoriform clade, whose members display these and other osteological characters thought to be correlated with the shift from carnivory to herbivory. This makes therizinosaurians prime candidates to assess the functional significance of these morphological characters. Based on a highly detailed biomechanical model of Erlikosaurus andrewsi, a therizinosaurid from the Upper Cretaceous of Mongolia, different morphological configurations incorporating soft-tissue structures, such as a keratinous rhamphotheca, are evaluated for their biomechanical performance. Our results indicate that the development of beaks and the presence of a keratinous rhamphotheca would have helped to dissipate stress and strain, making the rostral part of the skull less susceptible to bending and displacement, and this benefit may extend to other vertebrate clades that possess rhamphothecae. Keratinous beaks, paralleled by edentulism, thus represent an evolutionary innovation developed early in derived theropods to enhance cranial stability, distinct to postulated mass-saving benefits associated with the origin of flight.

  20. [Biomechanical risk assessment of manual material handling in vegetables and fruit departments of supermarkets].

    Science.gov (United States)

    Draicchio, F; Silvetti, A; Badellino, E; Vinci, F

    2007-01-01

    There is little in the literature about the risks of manual handling of material in supermarkets and what there is refers solely to storehouse work. This contrasts with the substantial number of studies of the risk of repeated arm movements among supermarket cash-desk staff. The scarcity of information is partly due to the difficulties of applying widely employed, standardized evaluation methods in this sector. One of the conditions limiting the application of the NIOSH protocol in this retail sector is that lifting tasks are so often closely tied to transport. The biomechanical analysis method we used brought to light considerable risks in many of the steps investigated: unpacking the pallet, unloading the crates from the pallet to the ground, lifting them from the floor onto display stands, and filling the boxes on the stands with goods before the shop opens. Images acquired on site were analyzed in the laboratory. We selected the most indicative images, which were then studied as regards posture and biomechanics using Apalys 3.0 software (ILMCAD GmbH, Ilmenau, Germany). Biomechemical analysis was done on the following movements: unloading crates from the pallet, positioning them on fruit and vegetable department display stands, and filling the boxes on the stands. We obtained a prediction of 2720 to 5472 N for the load at the lumbosacral junction (L5-S1). Simulation of the NIOSH index gave a value of 2.69 in the only case where the Waters protocol could be applied.

  1. 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...

  2. 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.

  3. Runners with patellofemoral pain have altered biomechanics which targeted interventions can modify: A systematic review and meta-analysis.

    Science.gov (United States)

    Neal, Bradley S; Barton, Christian J; Gallie, Rosa; O'Halloran, Patrick; Morrissey, Dylan

    2016-03-01

    Patellofemoral pain (PFP) is the most prevalent running pathology and associated with multi-level biomechanical factors. This systematic review aims to guide treatment and prevention of PFP by synthesising prospective, observational and intervention studies that measure clinical and biomechanical outcomes in symptomatic running populations. Medline, Web of Science and CINAHL were searched from inception to April 2015 for prospective, case-control or intervention studies in running-related PFP cohorts. Study methodological quality was scored by two independent raters using the modified Downs and Black or PEDro scales, with meta-analysis performed where appropriate. 28 studies were included. Very limited evidence indicates that increased peak hip adduction is a risk factor for PFP in female runners, supported by moderate evidence of a relationship between PFP and increased peak hip adduction, internal rotation and contralateral pelvic drop, as well as reduced peak hip flexion. Limited evidence was also identified that altered peak force and time to peak at foot level is a risk factor for PFP development. Limited evidence from intervention studies indicates that both running retraining and proximal strengthening exercise lead to favourable outcomes in both pain and function, but only running retraining significantly reduces peak hip adduction, suggesting a possible kinematic mechanism. Put together, these findings highlight limited but coherent evidence of altered biomechanics which interventions can alter with resultant symptom change in females with PFP. There is a clear need for high quality prospective studies of intervention efficacy with measurement of explanatory mechanisms.

  4. 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.

  5. Clinical application of shock wave therapy in musculoskeletal disorders: part II related to myofascial and nerve apparatus.

    Science.gov (United States)

    Saggini, R; Di Stefano, A; Saggini, A; Bellomo, R G

    2015-01-01

    Shock waves have been widely recognized in literature as a biological regulator; accordingly we carried out a review on the effect of shock waves on the mesenchymal cells in their various expressions: bone, muscle, ligament and tendon tissue. To date, the application of Shock Wave Therapy (SWT) in musculoskeletal disorders has been primarily used in the treatment of tendinopathies (proximal plantar fasciopathy, lateral elbow tendinopathy, calcific tendinopathy of the shoulder, and patellar tendinopathy, etc.) and bone defects (delayed and non-union of bone fractures, avascular necrosis of femoral head, etc.). Although the mechanism of their therapeutic effects is still unknown, the majority of published papers have shown the positive and beneficial effects of using SWT as a treatment for musculoskeletal disorders, with a success rate ranging from 65% to 91%, while the complications are low or negligible. The purpose of this paper is to present the published data on the clinical application of SWT in the treatment of myofascial and nerve disorders. With the help of the relevant literature, in this paper we outline the indications and success rates of SWT, as well as the adequate SWT parameters (e.g., rate of impulses, energy flux density) defined according to the present state of knowledge.

  6. Quantitative modelling of the biomechanics of the avian syrinx

    NARCIS (Netherlands)

    Elemans, C.P.H.; Larsen, O.N.; Hoffmann, M.R.; Leeuwen, van J.L.

    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

  7. Early Specialization in Youth Sport: A Biomechanical Perspective

    Science.gov (United States)

    Mattson, Jeffrey M.; Richards, Jim

    2010-01-01

    This article examines, from a biomechanical perspective, three issues related to early specialization: overuse injuries, the developmental aspects, and the performance aspects. It concludes that "there is no evidence that early specialization causes overuse injuries or hinders growth and maturation." At the same time, early specialization has…

  8. Lower Extremity Biomechanical Demands During Saut de Chat Leaps.

    Science.gov (United States)

    Jarvis, Danielle N; Kulig, Kornelia

    2016-12-01

    In dance, high demands are placed on the lower extremity joints during jumping tasks. The purpose of this study was to compare biomechanical demands placed on the lower extremity joints during the takeoff and landing phases of saut de chat leaps.

  9. 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.

  10. Changing step width alters lower extremity biomechanics during running.

    Science.gov (United States)

    Brindle, Richard A; Milner, Clare E; Zhang, Songning; Fitzhugh, Eugene C

    2014-01-01

    Step width is a spatiotemporal parameter that may influence lower extremity biomechanics at the hip and knee joint. The purpose of this study was to determine the biomechanical response of the lower extremity joints to step width changes during running. Lower extremity data from 30 healthy runners, half of them male, were collected during running in three step width conditions: preferred, wide, and narrow. Dependent variables and step width were analyzed using a mixed model ANOVA and pairwise t-tests for post hoc comparisons. Step width was successfully altered in the wide and narrow conditions. Generally, frontal plane peak values decreased as step width increased from narrow to preferred to wide. Peak hip adduction and rearfoot eversion angles decreased as step width increased from narrow to wide. Peak knee abduction moment and knee abduction impulse also decreased as step width increased from narrow to wide. Although men and women ran differently, gender only influenced the effect of step width on peak rearfoot inversion moment. In conclusion, step width influences lower extremity biomechanics in healthy runners. When step width increased from narrow to wide, peak values of frontal plane variables decreased. In addition to previously reported changes at the rearfoot, the hip and knee joint biomechanics were also influenced by changes in step width.

  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.

  12. 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...

  13. 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.…

  14. Biomechanics research in ski jumping, 1991-2006.

    Science.gov (United States)

    Schwameder, Hermann

    2008-01-01

    In this paper, I review biomechanics research in ski jumping with a specific focus on publications presented between 1991 and 2006 on performance enhancement, limiting factors of the take-off, specific training and conditioning, aerodynamics, and safety. The first section presents a brief description of ski jumping phases (in-run, take-off, early flight, stable flight, and landing) regarding the biomechanical and functional fundamentals. The most important and frequently used biomechanical methods in ski jumping (kinematics, ground reaction force analyses, muscle activation patterns, aerodynamics) are summarized in the second section. The third section focuses on ski jumping articles and research findings published after the establishment of the V-technique in 1991, as the introduction of this technique has had a major influence on performance enhancement, ski jumping regulations, and the construction of hill profiles. The final section proposes topics for future research in the biomechanics of ski jumping, including: take-off and early flight and the relative roles of vertical velocity and forward somersaulting angular momentum; optimal jumping patterns utilizing the capabilities of individual athletes; development of kinematic and kinetic feedback systems for hill jumps; comparisons of simulated and hill jumps; effect of equipment modifications on performance and safety enhancement.

  15. 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

  16. Qualitative Biomechanics and the Tennis Ground Strokes. Revised

    Science.gov (United States)

    Errington, Joseph

    This tennis stroke analysis, based on the application of biomechanic principles, is designed to help those who play tennis only once or twice a week. It is noted that, because the tennis player has a limited power potential, the only way to increase his racket head speed is to rotate his body. The mechanics of tennis are discussed by dividing it…

  17. Use of deterministic models in sports and exercise biomechanics research.

    Science.gov (United States)

    Chow, John W; Knudson, Duane V

    2011-09-01

    A deterministic model is a modeling paradigm that determines the relationships between a movement outcome measure and the biomechanical factors that produce such a measure. This review provides an overview of the use of deterministic models in biomechanics research, a historical summary of this research, and an analysis of the advantages and disadvantages of using deterministic models. The deterministic model approach has been utilized in technique analysis over the last three decades, especially in swimming, athletics field events, and gymnastics. In addition to their applications in sports and exercise biomechanics, deterministic models have been applied successfully in research on selected motor skills. The advantage of the deterministic model approach is that it helps to avoid selecting performance or injury variables arbitrarily and to provide the necessary theoretical basis for examining the relative importance of various factors that influence the outcome of a movement task. Several disadvantages of deterministic models, such as the use of subjective measures for the performance outcome, were discussed. It is recommended that exercise and sports biomechanics scholars should consider using deterministic models to help identify meaningful dependent variables in their studies.

  18. Biomechanics of the Gastrointestinal Tract in Health and Disease

    DEFF Research Database (Denmark)

    Zhao, Jingbo; Liao, Donghua; Gregersen, Hans

    2010-01-01

    . The biomechanical properties are crucial for GI motor function because peristaltic motion that propels the food through the GI tract is a result of interaction of the passive and active tissue forces and the hydrodynamic forces in the food bolus and remodeling of the mechanical properties reflects the changes...

  19. 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

  20. Biomechanical design considerations for transradial prosthetic interface: A review.

    Science.gov (United States)

    Sang, Yuanjun; Li, Xiang; Luo, Yun

    2016-03-01

    Traditional function and comfort assessment of transradial prostheses pay scant attention to prosthetic interface. With better understanding of the biomechanics of prosthetic interface comes better efficiency and safety for interface design; in this way, amputees are more likely to accept prosthetic usage. This review attempts to provide design and selection criteria of transradial interface for prosthetists and clinicians. Various transradial socket types in the literature were chronologically reviewed. Biomechanical discussion of transradial prosthetic interface design from an engineering point of view was also done. Suspension control, range of motion, stability, as well as comfort and safety of socket designs have been considered in varying degrees in the literature. The human-machine interface design should change from traditional "socket design" to new "interface design." From anatomy and physiology to biomechanics of the transradial residual limb, the force and motion transfer, together with comfort and safety, are the two main aspects in prosthetic interface design. Load distribution and transmission should mainly rely on achieving additional skeletal control through targeted soft tissue relief. Biomechanics of the residual limb soft tissues should be studied to find the relationship between mechanical properties and the comfort and safety of soft tissues.

  1. Future of crash dummies and biomechanical mathematical models

    NARCIS (Netherlands)

    Wismans, J.S.H.M.

    2000-01-01

    Thorough knowledge of the characteristics of the human body and its behaviour under extreme loading conditions is essential in order to prevent the serious consequences of road and other accidents. This field of research is called injury or impact biomechanics. In order to study the human body respo

  2. The biomechanical and physiological effect of two dynamic workstations

    NARCIS (Netherlands)

    Botter, J.; Burford, E.M.; Commissaris, D.; Könemann, R.; Mastrigt, S.H.V.; Ellegast, R.P.

    2013-01-01

    The aim of this research paper was to investigate the effect, both biomechanically and physiologically, of two dynamic workstations currently available on the commercial market. The dynamic workstations tested, namely the Treadmill Desk by LifeSpan and the LifeBalance Station by RightAngle, were com

  3. Computational Biomechanics of Human Red Blood Cells in Hematological Disorders.

    Science.gov (United States)

    Li, Xuejin; Li, He; Chang, Hung-Yu; Lykotrafitis, George; Em Karniadakis, George

    2017-02-01

    We review recent advances in multiscale modeling of the biomechanical characteristics of red blood cells (RBCs) in hematological diseases, and their relevance to the structure and dynamics of defective RBCs. We highlight examples of successful simulations of blood disorders including malaria and other hereditary disorders, such as sickle-cell anemia, spherocytosis, and elliptocytosis.

  4. Clinical Trial Design Principles and Endpoint Definitions for Transcatheter Mitral Valve Repair and Replacement: Part 1: Clinical Trial Design Principles: A Consensus Document From the Mitral Valve Academic Research Consortium.

    Science.gov (United States)

    Stone, Gregg W; Vahanian, Alec S; Adams, David H; Abraham, William T; Borer, Jeffrey S; Bax, Jeroen J; Schofer, Joachim; Cutlip, Donald E; Krucoff, Mitchell W; Blackstone, Eugene H; Généreux, Philippe; Mack, Michael J; Siegel, Robert J; Grayburn, Paul A; Enriquez-Sarano, Maurice; Lancellotti, Patrizio; Filippatos, Gerasimos; Kappetein, Arie Pieter

    2015-07-21

    Mitral regurgitation (MR) is one of the most prevalent valve disorders and has numerous etiologies, including primary (organic) MR, due to underlying degenerative/structural mitral valve (MV) pathology, and secondary (functional) MR, which is principally caused by global or regional left ventricular remodeling and/or severe left atrial dilation. Diagnosis and optimal management of MR requires integration of valve disease and heart failure specialists, MV cardiac surgeons, interventional cardiologists with expertise in structural heart disease, and imaging experts. The introduction of transcatheter MV therapies has highlighted the need for a consensus approach to pragmatic clinical trial design and uniform endpoint definitions to evaluate outcomes in patients with MR. The Mitral Valve Academic Research Consortium is a collaboration between leading academic research organizations and physician-scientists specializing in MV disease from the United States and Europe. Three in-person meetings were held in Virginia and New York during which 44 heart failure, valve, and imaging experts, MV surgeons and interventional cardiologists, clinical trial specialists and statisticians, and representatives from the U.S. Food and Drug Administration considered all aspects of MV pathophysiology, prognosis, and therapies, culminating in a 2-part document describing consensus recommendations for clinical trial design (Part 1) and endpoint definitions (Part 2) to guide evaluation of transcatheter and surgical therapies for MR. The adoption of these recommendations will afford robustness and consistency in the comparative effectiveness evaluation of new devices and approaches to treat MR. These principles may be useful for regulatory assessment of new transcatheter MV devices, as well as for monitoring local and regional outcomes to guide quality improvement initiatives.

  5. Clinical trial design principles and endpoint definitions for transcatheter mitral valve repair and replacement: part 1: clinical trial design principles: A consensus document from the mitral valve academic research consortium.

    Science.gov (United States)

    Stone, Gregg W; Vahanian, Alec S; Adams, David H; Abraham, William T; Borer, Jeffrey S; Bax, Jeroen J; Schofer, Joachim; Cutlip, Donald E; Krucoff, Mitchell W; Blackstone, Eugene H; Généreux, Philippe; Mack, Michael J; Siegel, Robert J; Grayburn, Paul A; Enriquez-Sarano, Maurice; Lancellotti, Patrizio; Filippatos, Gerasimos; Kappetein, Arie Pieter

    2015-08-01

    Mitral regurgitation (MR) is one of the most prevalent valve disorders and has numerous aetiologies, including primary (organic) MR, due to underlying degenerative/structural mitral valve (MV) pathology, and secondary (functional) MR, which is principally caused by global or regional left ventricular remodelling and/or severe left atrial dilation. Diagnosis and optimal management of MR requires integration of valve disease and heart failure specialists, MV cardiac surgeons, interventional cardiologists with expertise in structural heart disease, and imaging experts. The introduction of transcatheter MV therapies has highlighted the need for a consensus approach to pragmatic clinical trial design and uniform endpoint definitions to evaluate outcomes in patients with MR. The Mitral Valve Academic Research Consortium is a collaboration between leading academic research organizations and physician-scientists specializing in MV disease from the United States and Europe. Three in-person meetings were held in Virginia and New York during which 44 heart failure, valve, and imaging experts, MV surgeons and interventional cardiologists, clinical trial specialists and statisticians, and representatives from the U.S. Food and Drug Administration considered all aspects of MV pathophysiology, prognosis, and therapies, culminating in a 2-part document describing consensus recommendations for clinical trial design (Part 1) and endpoint definitions (Part 2) to guide evaluation of transcatheter and surgical therapies for MR. The adoption of these recommendations will afford robustness and consistency in the comparative effectiveness evaluation of new devices and approaches to treat MR. These principles may be useful for regulatory assessment of new transcatheter MV devices, as well as for monitoring local and regional outcomes to guide quality improvement initiatives.

  6. [Clinical practice guidelines: Irritable bowel syndrome with constipation and functional constipation in adults: Concept, diagnosis, and healthcare continuity. (Part 1 of 2)].

    Science.gov (United States)

    Mearin, F; Ciriza, C; Mínguez, M; Rey, E; Mascort, J J; Peña, E; Cañones, P; Júdez, J

    2017-01-01

    In this Clinical practice guide, an analysis is made of the diagnosis and treatment of adult patients with constipation and abdominal discomfort, under the spectrum of irritable bowel syndrome and functional constipation. These have an important personal, health and social impact, affecting the quality of life of these patients. In irritable bowel syndrome with a predominance of constipation, this is the predominant change in bowel movements, with recurrent abdominal pain, bloating and frequent abdominal distension. Constipation is characterised by infrequent or difficulty in bowel movements, associated with excessive straining during bowel movement or sensation of incomplete evacuation. There is often no underling cause, with an intestinal functional disorder being considered. They have many clinical and pathophysiological similarities, with a similar response of the constipation to common drugs. The fundamental difference is the presence or absence of pain, but not in a way evaluable way; "all or nothing". The severity depends on the intensity of bowel symptoms and other factors, a combination of gastrointestinal and extra-intestinal symptoms, level of involvement, forms of perception, and behaviour. The Rome criteria diagnose functional bowel disorders. This guide is adapted to the Rome criteria IV (May 2016) and in this first part an analysis is made of the alarm criteria, diagnostic tests, and the criteria for referral between Primary Care and Digestive Disease specialists. In the second part, a review will be made of the therapeutic alternatives available (exercise, diet, drug therapies, neurostimulation of sacral roots, or surgery), making practical recommendations for each one of them.

  7. 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

  8. 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.

  9. Biomechanical and neural changes evaluation induced by prolonged use of non-stable footwear: a systematic review.

    Science.gov (United States)

    Papalia, R; Di Pino, G; Tecame, A; Vadalà, G; Formica, D; Di Martino, A; Albo, E; Di Lazzaro, V; Denaro, V

    2015-12-01

    The aim of this review is to collect and discuss the current best evidence published in literature about the effect of the Masai Barefoot Technology(MBT) shoes on gait and muscle activation and try to draw conclusions on the possible benefits. We searched Medline, CINAHL, Embase and the Cochrane Central Registry of Controlled Trials. The reference lists of the previously selected articles were then examined by hand. Only studies comparing biomechanical and clinical outcomes were selected. Review, anatomical studies, letter to editor and instructional course were excluded. Finally, all the resulting articles were reviewed and discussed by all the authors to further confirm their suitability for this review: in the end, 22 articles were included. A total of 532 patients presenting a mean age of 34.3 years were studied. All patients evaluated were healthy or amateur sports except in two studies where only obese subjects and knee osteoarthritis patients were involved. Seven studies evaluated only male subjects, whereas four studies evaluated only female. Twelve of twenty-two studies performed electromyographic analyses. Weight was reported in 19 studies, whereas body mass index were reported only in a five studies. All studies reported kinematic analysis of shoe effects and compared the relationship between muscle recruitment and electromyographic activity. Unstable footwears were shown to immediately alter the stability in gait during daily-life activities. The center of body pressure is moved posteriorly with a consequent posterior displacement of the upper part of body in order to regain an appropriate body balance, and these postural changes are associated with an overall increase in the activity of lumbar erector spine muscles, as well as certain lower limb muscles. Current literature provides enough cues to conclude for a beneficial role of MBT shoes in the postural and proprioceptive recovery, but from the same literature cannot be drown clear and appropriate

  10. Comparative biomechanical study of reversed less invasive stabilization system and proximal femoral nail antirotation for unstable intertrochanteric fractures

    Institute of Scientific and Technical Information of China (English)

    Chen Ying; Liu Shouyao; Lin Peng; Wang Yunting; Wang Jinhui; Tao Jianfeng; Cai Rongrong

    2014-01-01

    Objective Unstable intertrochanteric fractures (ITFs) are mostly treated by proximal femoral nail antirotation (PFNA),Inter-Tan,Asian Hip,and other new internal fixation devices.But for complex unstable fractures,such as crushed lateral wall of the greater trochanter,the loss of fixation point on lateral wall slightly reduces the fixing effect.This study aimed to compare the biomechanical strengths between reversed less invasive stabilization system (LISS) and PFNA for treatment of unstable ITFs.Methods Forty synthetic femurs were used to simulate unstable ITFs in vitro and were fixed using the reversed LISS or PFNA.These fractures were divided into two groups depending on whether the lateral wall of the greater trochanter is intact or not (AO classification:31-A2.3 and 31-A3.3,respectively).The load-displacement of femur,stiffness,ultimate load,and cyclic fatigue resistance were detected using an incremental load test and a dynamic fatigue test through an MTS 858 test system.Results For both 31-A2.3 and 31-A3.3,the vertical sinking displacement (VSD) of the femoral head under 500 N load was insignificantly smaller after treatment with reversed LISS than with PFNA,and when the displacement was 5 mm,the femoral head bore insignificantly greater load.The fixation with reversed LISS resulted in greater axial stiffness of the femur but smaller ultimate load.During the same cycle in the dynamic fatigue test,the VSD was insignificantly smaller with the fixation of reversed LISS.Conclusion Reversed LISS and PFNA have similar biomechanical strength for unstable ITFs.This conclusion should be supported by additional large-size research on basic biomechanics and clinical application.This is the first comparative biomechanical study comparing reversed LISS and PFNA for unstable ITFs.

  11. Clinical, virological and immunological responses in Danish HIV patients receiving raltegravir as part of a salvage regimen

    Directory of Open Access Journals (Sweden)

    Frederik N Engsig

    2010-05-01

    Full Text Available Frederik N Engsig1, Jan Gerstoft1, Gitte Kronborg2, Carsten S Larsen3, Gitte Pedersen4, Anne M Audelin5, Louise B Jørgensen5, Niels Obel11Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Denmark; 2Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark; 3Department of Infectious Diseases, Aarhus University Hospital, Aarhus, Denmark; 4Department of Infectious Diseases, Aalborg University Hospital, Aalborg, Denmark; 5Department of Virology, Statens Serum Institute, Copenhagen, DenmarkBackground: Raltegravir is the first integrase inhibitor approved for treatment of HIV-infected patients harboring multiresistant viruses.Methods: From a Danish population-based nationwide cohort of HIV patients we identified the individuals who initiated a salvage regimen including raltegravir and a matched cohort of HIV-infected patients initiating HAART for the first time. We compared these two cohorts for virological suppression, gain in CD4 count, and time to first change of initial regimen.Results: We identified 32 raltegravir patients and 64 HIV patients who initiated HAART for the first time in the period 1 January 2006 to 1 July 2009. The virological and immunological responses in the raltegravir patients were comparable to those seen in the control cohort. No patients in the two cohorts died and no patients terminated raltegravir treatment in the observation period. Time to first change of initial regimen was considerably shorter for HAART-naïve patients.Conclusion: We conclude that salvage regimens including raltegravir have high effectiveness in the everyday clinical setting. The effectiveness of the regimens is comparable to that observed for patients initiating HAART for the first time. The risk of change in the salvage regimens after initiation of raltegravir is low.Keywords: HIV, raltegravir, salvage regime, efficacy, matched cohort

  12. Trial by Dutch laboratories for evaluation of non‐invasive prenatal testing. Part I—clinical impact

    Science.gov (United States)

    Oepkes, Dick; Page‐Christiaens, G. C. (Lieve); Bax, Caroline J.; Bekker, Mireille N.; Bilardo, Catia M.; Boon, Elles M. J.; Schuring‐Blom, G. Heleen; Coumans, Audrey B. C.; Faas, Brigitte H.; Galjaard, Robert‐Jan H.; Go, Attie T.; Henneman, Lidewij; Macville, Merryn V. E.; Pajkrt, Eva; Suijkerbuijk, Ron F.; Huijsdens‐van Amsterdam, Karin; Van Opstal, Diane; Verweij, E. J. (Joanne); Weiss, Marjan M.

    2016-01-01

    Abstract Objective To evaluate the clinical impact of nationwide implementation of genome‐wide non‐invasive prenatal testing (NIPT) in pregnancies at increased risk for fetal trisomies 21, 18 and 13 (TRIDENT study). Method Women with elevated risk based on first trimester combined testing (FCT ≥ 1:200) or medical history, not advanced maternal age alone, were offered NIPT as contingent screening test, performed by Dutch University Medical laboratories. We analyzed uptake, test performance, redraw/failure rate, turn‐around time and pregnancy outcome. Results Between 1 April and 1 September 2014, 1413/23 232 (6%) women received a high‐risk FCT result. Of these, 1211 (85.7%) chose NIPT. One hundred seventy‐nine women had NIPT based on medical history. In total, 1386/1390 (99.7%) women received a result, 6 (0.4%) after redraw. Mean turn‐around time was 14 days. Follow‐up was available in 1376 (99.0%) pregnancies. NIPT correctly predicted 37/38 (97.4%) trisomies 21, 18 or 13 (29/30, 4/4 and 4/4 respectively); 5/1376 (0.4%) cases proved to be false positives: trisomies 21 (n = 2), 18 (n = 1) and 13 (n = 2). Estimated reduction in invasive testing was 62%. Conclusion Introduction of NIPT in the Dutch National healthcare‐funded Prenatal Screening Program resulted in high uptake and a vast reduction of invasive testing. Our study supports offering NIPT to pregnant women at increased risk for fetal trisomy. © 2016 The Authors. Prenatal Diagnosis published by John Wiley & Sons, Ltd. © 2016 The Authors. Prenatal Diagnosis published by John Wiley & Sons, Ltd. PMID:27750376

  13. 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.

  14. Effects of osteoporosis therapies on bone biomechanics

    OpenAIRE

    2010-01-01

    Anti-fracture therapies for the treatment of osteoporosis have been shown clinically to reduce the incidence of fracture; however, standard clinical measurements of bone density cannot sufficiently explain these large reductions. Therefore, the overall goal of this research is to develop a better understanding of the mechanisms through which anti-fracture therapies improve bone strength -- a critical determinant of fracture risk -- which should lead to improved assessment of treatment efficac...

  15. 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.

  16. Clinical Application of Cone Beam Computed Tomography of the Rabbit Head: Part 2—Dental Disease

    Science.gov (United States)

    Riggs, G. G.; Cissell, Derek D.; Arzi, Boaz; Hatcher, David C.; Kass, Philip H.; Zhen, Amy; Verstraete, Frank J. M.

    2017-01-01

    Domestic rabbits are increasing in popularity as household pets; therefore, veterinarians need to be familiar with the most common diseases afflicting rabbits including dental disease. Current diagnostic approaches include gross oral examination, endoscopic oral examination, skull radiography, and computed tomography (CT). Cone beam computed tomography (CBCT), a new oral and maxillofacial imaging modality that has the capability to produce high-resolution images, has not yet been described for use in evaluating dental disease in rabbits. A total of 15 client-owned rabbits had CBCT, oral examination, dental charting, and dental treatment performed under general anesthesia. Images were evaluated using transverse and custom multiplanar (MPR), 3D, and panoramic reconstructed images. The CBCT findings were grouped into abnormalities that could be detected on conscious oral examination vs. abnormalities that could not be detected by conscious oral examination. Potential associations between the two categories were examined by pairwise Fisher’s exact test with statistical significance determined by P < 0.05. The most common findings identified on CBCT images were periodontal ligament space widening (14/15), premolar and molar malocclusion (13/15), apical elongation (13/15), coronal elongation (12/15), inflammatory tooth resorption (12/15), periapical lucency (11/15), moth-eaten pattern of osteolysis of the alveolar bone (9/15), ventral mandibular border contour changes (9/15), and missing teeth (8/15). Of the CBCT abnormalities likely to be observed on oral examination, coronal elongation (detectable on oral examination) was significantly associated with apical elongation (P = 0.029). There were no other significant associations between CBCT findings that are also clinically detectable and CBCT findings that are not be detectable on oral examination. This suggests that pathology often exists that is not apparent upon oral examination. This study establishes the

  17. 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

  18. The clinical response to infliximab in rheumatoid arthritis is in part dependent on pretreatment tumour necrosis factor α expression in the synovium

    Science.gov (United States)

    Wijbrandts, C A; Dijkgraaf, M G W; Kraan, M C; Vinkenoog, M; Smeets, T J; Dinant, H; Vos, K; Lems, W F; Wolbink, G J; Sijpkens, D; Dijkmans, B A C; Tak, P P

    2008-01-01

    Objective: To determine whether the heterogeneous clinical response to tumour necrosis factor (TNF)α blocking therapy in rheumatoid arthritis (RA) can be predicted by TNFα expression in the synovium before initiation of treatment. Methods: Prior to initiation of infliximab treatment, arthroscopic synovial tissue biopsies were obtained from 143 patients with active RA. At week 16, clinical response was evaluated using the 28-joint Disease Activity Score (DAS28). Immunohistochemistry was used to analyse the cell infiltrate as well as the expression of various cytokines, adhesion molecules and growth factors. Stained sections were evaluated by digital image analysis. Student t tests were used to compare responders (decrease in DAS28 ⩾1.2) with non-responders (decrease in DAS28 <1.2) and multivariable regression was used to identify the independent predictors of clinical response. Results: Synovial tissue analysis confirmed our hypothesis that the baseline level of TNFα expression is a significant predictor of response to TNFα blocking therapy. TNFα expression in the intimal lining layer and synovial sublining were significantly higher in responders than in non-responders (p = 0.047 and p = 0.008, respectively). The numbers of macrophages, macrophage subsets and T cells (all able to produce TNFα) were also significantly higher in responders than in non-responders. The expression of interleukin (IL)1β, IL6, IL18, IL10, E-selectin, intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) was not associated with response to anti-TNFα treatment. Conclusion: The effects of TNFα blockade are in part dependent on synovial TNFα expression and infiltration by TNFα producing inflammatory cells. Clinical response cannot be predicted completely, indicating involvement of other as yet unknown mechanisms. PMID:18055470

  19. 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

  20. Biomechanics/risk management (Working Group 2)

    DEFF Research Database (Denmark)

    Sanz, Mariano; Naert, Ignace; Gotfredsen, Klaus

    2009-01-01

    survival and complications of implant supported restorations? * A systematic review on the accuracy and the clinical outcome of computer-guided template based implant dentistry. * What is the impact of systemic bisphosphonates on patients undergoing oral implant therapy? * What is the impact...... of anticoagulants on patients undergoing oral implant therapy?...