Abstract：
:Children with cerebral palsy frequently experience foot dragging and tripping during walking due to a lack of adequate knee flexion in swing (stiff-knee gait). Stiff-knee gait is often accompanied by an overly flexed knee during stance (crouch gait). Studies on stiff-knee gait have mostly focused on excessive knee muscle activity during (pre)swing, but the passive dynamics of the limbs may also have an important effect. To examine the effects of a crouched posture on swing knee flexion, we developed a forward-dynamic model of human walking with a passive swing knee, capable of stable cyclic walking for a range of stance knee crouch angles. As crouch angle during stance was increased, the knee naturally flexed much less during swing, resulting in a 'stiff-knee' gait pattern and reduced foot clearance. Reduced swing knee flexion was primarily due to altered gravitational moments around the joints during initial swing. We also considered the effects of increased push-off strength and swing hip flexion torque, which both increased swing knee flexion, but the effect of crouch angle was dominant. These findings demonstrate that decreased knee flexion during swing can occur purely as the dynamical result of crouch, rather than from altered muscle function or pathoneurological control alone.
journal_name
Ann Biomed Engjournal_title
Annals of biomedical engineeringauthors
van der Krogt MM,Bregman DJ,Wisse M,Doorenbosch CA,Harlaar J,Collins SHdoi
10.1007/s10439-010-9952-2subject
Has Abstractpub_date
2010-04-01 00:00:00pages
1593-606issue
4eissn
0090-6964issn
1573-9686journal_volume
38pub_type
杂志文章abstract：:Continuous measurement of arterial blood density after bolus injection of fluids of different density into the right atrium has been used to measure cardiac output and mean transit time through the central circulation. The transit time distribution for density, however, differs from that for plasma-phase tracers such ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/BF02368628
更新日期：1993-07-01 00:00:00
abstract：:The second equation in the section "Definition of Objective Functions and Constraints" was corrected to fix a mismatch between the PDF and HTML versions of the article. ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章,已发布勘误
doi：10.1007/s10439-019-02413-y
更新日期：2020-01-01 00:00:00
abstract：:The nonlinear dynamic properties of action potential encoding were studied in mechanosensory neurons innervating the slits of a slit-sense organ in the tropical wandering spider, Cupiennius salei. The organ contains two types of neurons that are morphologically similar but have different dynamic properties. Type A neu...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1114/1.1355278
更新日期：2001-03-01 00:00:00
abstract：:This article presents a computer-aided detection system for capsule endoscopy (CE) images using contourlet-based color textural features to recognize tumors in the digestive tract. As tumor exhibits rich information in color texture, a novel color texture feature based on contourlet transform is proposed to describe c...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-011-0380-8
更新日期：2011-12-01 00:00:00
abstract：:Parameters of physiological models are commonly associated in an input-output experiment with a specific pattern of the system response. This association is often made on an intuitive basis by traditional sensitivity analysis, i.e., by inspecting the variations of model output trajectories with respect to parameter va...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1114/1.207
更新日期：1999-09-01 00:00:00
abstract：:High energy laser has emerged to be an important surgical tool in medical technology. However, the application of laser energy to drill or cut a bone is still in an experimental state. In order to estimate the adequacy of laser heating of bone surface and at the same time minimize the damage to the bone tissue, we dev...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/BF02363565
更新日期：1987-01-01 00:00:00
abstract：:This study was undertaken to investigate the possible origin of some cutaneously recorded higher frequency electrogastrographic signals. Computer modeling of gastric electrical uncoupling was performed using previously described conoidal dipole model. Cutaneous electrogastrograms were simulated after uncoupling was in...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：
更新日期：1997-11-01 00:00:00
abstract：:Accurate identification of contracting muscles can help us to understand the muscle function in both physiological and pathological conditions. Conventional electromyography (EMG) have limited access to deep muscles, crosstalk, or instability in the recordings. Accordingly, a novel framework was developed to detect co...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-020-02557-2
更新日期：2021-01-01 00:00:00
abstract：:In order to increase the probability of having a successful cataract post-surgery, the customisation of the haptic design of the intraocular lens (IOL) according to the characteristics of the patient is recommended. In this study, we present two prediction models based on deep neural networks (DNNs). One is capable of...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-020-02636-4
更新日期：2020-12-01 00:00:00
abstract：:A major drawback in the operation of mechanical heart valve prostheses is thrombus formation in the near valve region. Detailed flow analysis in this region during the valve closure phase is of interest in understanding the relationship between shear stress and platelet activation. A fixed-grid Cartesian mesh flow sol...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-006-9194-5
更新日期：2006-10-01 00:00:00
abstract：:The longitudinal assessment of joint health is a long-standing issue in the management of musculoskeletal injuries. The acoustic emissions (AEs) produced by joint articulation could serve as a biomarker for joint health assessment, but their use has been limited by a lack of mechanistic understanding of their creation...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-019-02333-x
更新日期：2020-01-01 00:00:00
abstract：:Icariin (Ic) has been demonstrated as a potent osteoinductive compound for bone tissue engineering. However, toxic side effects of the drug and poor biocompatibility of drug delivery systems (DDSs) still limit its application for bone repair in the clinic. To overcome these disadvantages and utilize the osteoinductivi...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-017-1900-y
更新日期：2017-11-01 00:00:00
abstract：:Microscopic steps and crevices are inevitable features within prosthetic blood-contacting devices. This study aimed to elucidate the thrombogenicity of the associated microscopic flow features by studying the transport of fluorescent platelet-sized particles in a suspension of red blood cells (RBCs) flowing through a ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-008-9494-z
更新日期：2008-07-01 00:00:00
abstract：:Mitral valve regurgitation (MVR) is common in patients receiving left ventricular assist device (LVAD) support, however the haemodynamic effect of MVR is not entirely clear. This study evaluated the haemodynamic effect of MVR with LVAD support and the influence of inflow cannulation site and LVAD speed modulation. Lef...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-016-1579-5
更新日期：2016-09-01 00:00:00
abstract：:Cell migration is a fundamental process that is crucial to a variety of physiological events. While traditional approaches have focused on two-dimensional (2D) systems, recent efforts have shifted to studying migration in three-dimensional (3D) matrices. A major distinction that has emerged is the increased importance...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-010-9970-0
更新日期：2010-05-01 00:00:00
abstract：:Intra-cardiac flow has been explored for decades but there is still no consensus on whether or not healthy left ventricles (LV) may harbour turbulent-like flow despite its potential physiological and clinical relevance. The purpose of this study is to elucidate if a healthy LV could harbour flow instabilities, using i...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-016-1614-6
更新日期：2016-11-01 00:00:00
abstract：:The objective of this work is to develop understanding of the local fluid dynamic mechanisms that underpin gas exchange in high-frequency oscillatory ventilation (HFOV). The flow field during HFOV was investigated experimentally using particle image velocimetry in idealized and realistic models of a single bifurcation...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-008-9557-1
更新日期：2008-11-01 00:00:00
abstract：:The linear homeomorphic muscle model proposed by Enderle and coworkers for the rectus eye muscle is fitted to reflect the dynamics of muscles in the head-neck complex, specifically in muscles involved in gaze shifts. This parameterization of the model for different muscles in the neck region will serve to drive a 3D d...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-009-9851-6
更新日期：2010-02-01 00:00:00
abstract：:Correct development of neuronal tracts requires the coordination of multiple permissive and inhibitory signals. By generating an in vitro microenvironment using soft lithography and microfluidic techniques, multiple guidance cues can be presented in a spatially defined way. Here we evaluated how neurites of dorsal roo...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-008-9486-z
更新日期：2008-06-01 00:00:00
abstract：:Continuous gradients exist at osteochondral interfaces, which may be engineered by applying spatially patterned gradients of biological cues. In the present study, a protein-loaded microsphere-based scaffold fabrication strategy was applied to achieve spatially and temporally controlled delivery of bioactive signals i...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-010-0028-0
更新日期：2010-06-01 00:00:00
abstract：:Further understanding of the mechanical deformation and tear behavior of kidney during suturing helps to enhance surgical task execution that requires fine suture manipulation. This paper aims to develop a model to describe the relationship between the tensile force acting on suture line and the resulted kidney deform...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-012-0722-1
更新日期：2013-04-01 00:00:00
abstract：:A major benefit of computational modeling in biomechanics research is its ability to estimate internal muscular demands given limited input information. However, several assumptions regarding model parameters and constraints may influence model outputs. This research evaluated the influence of model parameter variabil...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-014-1035-3
更新日期：2014-09-01 00:00:00
abstract：:The neutrophil has developed into one of the most efficient vertebrate motile cells. It migrates through tissues, where it encounters multiple chemoattractant signals with complex spatial and temporal characteristics. The directional movement of the neutrophil is signaled by the binding of chemoattractants and chemoki...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章,评审
doi：10.1114/1.1477446
更新日期：2002-03-01 00:00:00
abstract：:Maintenance of movement accuracy relies on motor learning, by which prior errors guide future behavior. One aspect of this learning process involves the accurate generation of predictions of movement outcome. These predictions can, for example, drive anticipatory movements during a predictive-saccade task. Predictive ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-012-0669-2
更新日期：2013-08-01 00:00:00
abstract：:Due to its unique non-invasive microstructure probing capabilities, diffusion tensor imaging (DTI) constitutes a valuable tool in the study of fiber orientation in skeletal muscles. By implementing a DTI sequence with judiciously chosen directional encoding to quantify in vivo the microarchitectural properties in the ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-009-9783-1
更新日期：2009-12-01 00:00:00
abstract：:Fractal time series analysis methods are commonly used for analyzing center of pressure (COP) signals with the goal of revealing the underlying neuromuscular processes for upright stance control. The use of fractal methods is often coupled with the assumption that the COP is an instance of fractional Gaussian noise (f...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-012-0646-9
更新日期：2013-08-01 00:00:00
abstract：:An intelligent multichannel stimulator (IMS) has been designed and built for use in a cardiac research environment. The device is capable of measuring and responding to cardiac electrophysiological phenomena in real time with carefully timed and placed electrical stimuli. The system consists of 16 channels of sense/st...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1114/1.1451077
更新日期：2002-02-01 00:00:00
abstract：:Magnetic (eddy-current) stimulation of the inspiratory motor nerves in the neck of the anesthetized dog was achieved. Using a 10-turn coil wound around the base of the neck and a train of pulses (25/s), inspiration was produced by tetanic contraction of the inspiratory muscles. The volume of air inspired increased wit...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/BF02368176
更新日期：1993-05-01 00:00:00
abstract：:In the field of fluid flow within the human body, focus has been placed on the transportation of blood in the systemic circulation since the discovery of that system; but, other fluids and fluid flow phenomena pervade the body. Some of the most fascinating fluid flow phenomena within the human body involve fluids othe...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-010-9902-z
更新日期：2010-03-01 00:00:00
abstract：:We seek to construct physical and mathematical models of life. Such models allow us to test our understanding of how living systems function and how they respond to human imposed stimuli. One system is a genomically and chemically complete model of a minimal cell. This cell is a hypothetical bacterium with the fewest ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章,评审
doi：10.1007/s10439-012-0567-7
更新日期：2012-07-01 00:00:00
