Abstract：
:The purpose of the study was to evaluate the rates of change in the estimated masses and principal moments of inertia of the body segments during the second and third trimesters of pregnancy. Fifteen subjects, on average 15.1 weeks pregnant, were tested monthly until term. The body was modelled as 16 segments consisting of 2 cm stacked elliptical cylinders sectioned in the transverse plane. Linear regressions were fitted to the segment inertias and regression coefficients determined for the individual growth curves. The mean rate of increase for the lower trunk mass was 0.29 kg per week and 0.0069 kg m2 per week for the transverse axis principal moment. Differences between the means of the segments for rates of change of mass and the three principal moments were then tested. All four ANOVAs used to test the differences were significant. The post hoc analysis established that over the second and third trimesters the lower trunk inertias increased at a greater rate than all other segments and there were no significant differences between the remaining segments. The effect of such changes in the trunk segment masses and principal moments was illustrated by an analysis of intersegmental dynamics during a sit to stand of one pregnant subject whose lower trunk mass increased from 21.6 kg to 28.4 kg. A knowledge of the differences in an individual's segment inertias should lead to a better understanding of how movements are affected during pregnancy.
journal_name
J Biomechjournal_title
Journal of biomechanicsauthors
Jensen RK,Doucet S,Treitz Tdoi
10.1016/0021-9290(95)00042-9subject
Has Abstractpub_date
1996-02-01 00:00:00pages
251-6issue
2eissn
0021-9290issn
1873-2380pii
0021929095000429journal_volume
29pub_type
杂志文章abstract：:A biomechanical model of the human thorax was constructed to investigate how asymmetric growth of the thorax might initiate spinal lateral curvature and axial rotation as seen in scoliosis deformities. Geometric data specifying nodal points of the model were taken from stereo-radiographs of an adolescent subject. An i...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/0021-9290(90)90051-4
更新日期：1990-01-01 00:00:00
abstract：:Shorter generation time and the power of genetic manipulation make mice an ideal model system to study bone biology as well as bone diseases. However their small size presents a challenge to perform strength measurements, particularly of the weight-bearing cancellous bone in the murine long bones. We recently develope...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2016.02.040
更新日期：2016-05-03 00:00:00
abstract：:The purpose of this project was to study a noninvasive method of evaluating limbs at risk of compartment syndrome. Untreated limb compartment syndrome may lead to irreversible dysfunction, chronic pain and contracture. An improved means of obtaining quantitative hardness measurements is reported. The handheld noninvas...
journal_title：Journal of biomechanics
pub_type： 临床试验,杂志文章
doi：10.1016/j.jbiomech.2004.07.030
更新日期：2005-08-01 00:00:00
abstract：:A biomechanical model of the forearm, consisting of 61 muscle-tendon systems or tendons and 8 sections, is presented. The model can be used to calculate the muscle forces when resultant of the external forces and the motion is known. Calculations are based on constraints of muscle forces, joint forces, contact forces,...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/s0021-9290(01)00009-4
更新日期：2001-05-01 00:00:00
abstract：:The pleural surfaces of the chest wall and lung slide against each other, lubricated by pleural fluid. During sliding motion of soft tissues, shear induced hydrodynamic pressure deforms the surfaces, promoting uniformity of the fluid layer thickness, thereby reducing friction. To assess pleural deformability at length...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2011.07.008
更新日期：2011-09-23 00:00:00
abstract：:It is well known that cyclic mechanical loading can produce an anabolic response in bone. In vivo studies have shown that the insertion of short-term recovery periods (10-15 s) into mechanical loading profiles led to an increased osteogenic response compared to continuous cyclic loading of bone. Although this is sugge...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2004.08.009
更新日期：2005-09-01 00:00:00
abstract：:In vivo measurements of the loads and deformations occurring in orthopaedic implants will allow future improvements to be made. This paper describes an extremely small telemetry for long term measurements with three strain gauges and methods for an absolutely safe implant design. Developed for measuring the load at hi...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/0021-9290(88)90009-7
更新日期：1988-01-01 00:00:00
abstract：:Knee joint sounds contain information on joint health, morphology and loading. These acoustic signals may be elicited by further, as yet unknown factors. By assessing potential elicitors and their relative contributions to the acoustic signal, we investigated the validity of vibroarthrographic assessments during diffe...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2020.109939
更新日期：2020-08-26 00:00:00
abstract：:Subchondral bone undecalcified samples, extracted from bovine femoral heads, are subjected to a direct tensile load. The Young's modulus of each sample is determined from repeated tests within the elastic limit. In a last test, the tensile load is increased up to the specimen failure, determining the ultimate tensile ...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/s0021-9290(00)00074-9
更新日期：2000-09-01 00:00:00
abstract：:The biomechanical characteristics of bone tissue and its cells under mechanical stress are significant for bone biomechanics research, but the mechanism of mechanotransduction is still unknown. It has been established that the actin cytoskeleton of osteoblasts plays an important role in this process. However, the stru...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2008.08.010
更新日期：2008-11-14 00:00:00
abstract：:Subject-specific musculoskeletal models require accurate values of muscle moment arms. The aim of this study was to compare moment arms of wrist tendons obtained from non-invasive magnetic resonance imaging (MRI) to those obtained from an in vitro experimental approach. MRI was performed on ten upper limb cadaveric sp...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2017.12.024
更新日期：2018-02-08 00:00:00
abstract：:We assessed the local distribution of bone mechanical properties on a micro-nano-scale and its correlation to strain distribution. Left tibia samples were obtained from 5-month old female Sprague Dawley rats, including baseline control (n=9) and hindlimb suspended (n=9) groups. Elastic modulus was measured by nanoinde...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2015.11.052
更新日期：2016-01-25 00:00:00
abstract：:The three-dimensional geometry of the human spine is noteworthy information that can be obtained by stereoradiographic methods. These methods are based on the identification of anatomical structures in several views which are obtained by rotation of a patient standing on a turntable. Calibration algorithms for compute...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/s0021-9290(03)00016-2
更新日期：2003-06-01 00:00:00
abstract：:Evaluation of anterior laxity of the ankle joint complex is a difficult clinical problem. Currently, the prime determinant for anterolateral ligament function is the subjective manual examination of anterior laxity of the ankle joint complex. An instrumented dynamic test was developed for objective measurement of ante...
journal_title：Journal of biomechanics
pub_type： 临床试验,杂志文章
doi：10.1016/s0021-9290(02)00189-6
更新日期：2002-12-01 00:00:00
abstract：:In this study, human tibia plateaus with the meniscus removed were impacted on various regions of the plateau surface via a drop test using a 5mm indenter. Osteochondral blocks containing the failure site were then extracted, chemically fixed, dehydrated, gold-particle coated, and sent for X-ray micro-CT imaging to ob...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2008.01.033
更新日期：2008-01-01 00:00:00
abstract：:The objective of this work is to gain more insight into the processes of oral perception of food texture. Particularly, the limits for detectable thickness differences of objects, which are evaluated in the human mouth, are investigated. In a sensory study small, flexible circular disks (diameter in mm range) of varyi...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2007.04.012
更新日期：2007-01-01 00:00:00
abstract：:A pair of finite element models has been employed to study the interaction of blood flow with the operation of the aortic valve. A three-dimensional model of the left ventricle with applied wall displacements has been used to generate data for the spatially and time-varying blood velocity profile across the aortic ape...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2004.10.038
更新日期：2006-01-01 00:00:00
abstract：:Although micromechanical finite-element models are being increasingly used to help interpret the results of bio-mechanical tests, there has not yet been a systematic study of the numerical errors and uncertainties that occur with these methods. In this work, finite-element models of human L1 vertebra have been used to...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/s0021-9290(98)00108-0
更新日期：1998-10-01 00:00:00
abstract：:The aim of this work is to specify which model of turbulence is the most adapted in order to predict the drag forces that a swimmer encounters during his movement in the fluid environment. For this, a Computational Fluid Dynamics (CFD) analysis has been undertaken with a commercial CFD code (Fluent). The problem was m...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2009.10.010
更新日期：2010-02-10 00:00:00
abstract：:Here we present a study on the impact of assumptions on image-based hemodynamic simulations of healthy carotid bifurcations. In particular, we evaluate to which extent assumptions on blood rheology influence bulk flow features, driven by the fact that few studies have provided adequate insights into the influence of a...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2011.06.028
更新日期：2011-09-02 00:00:00
abstract：:The drop vertical jump (DVJ) task is commonly used to assess biomechanical performance measures that are associated with ACL injury risk in athletes. Previous investigations have solely assessed the first landing phase. We examined the first and second landings of a DVJ for differences in the magnitude of vertical gro...
journal_title：Journal of biomechanics
pub_type： 临床试验,杂志文章
doi：10.1016/j.jbiomech.2013.02.024
更新日期：2013-04-26 00:00:00
abstract：:In this paper, we apply the micropipette to reduce the surface area of the rabbit aorta, and the relationship between the fractional area change of the aortic surface and the negative pressure in the pipette is studied. The experimental results for seven rabbit thoracic aortas show that the relationship can be express...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/0021-9290(96)00003-6
更新日期：1996-08-01 00:00:00
abstract：:We present a comparison of the flow characteristics in an idealized smooth trachea model and a second model which has a roughness simulating cartilaginous rings. We use refractive index-matched particle image velocimetry (PIV) to measure the velocity field in a two-generation model of the trachea and main bronchi. The...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2016.03.043
更新日期：2016-06-14 00:00:00
abstract：:None of the physical testing, nor the goniometers currently used to assess upper limb function have a high validity, sensitivity or reliability. The reachable workspace, i.e. the area covered by the farthest points a subject can reach by hand without moving his/her body, shows promise but has yet to be validated, part...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2017.12.010
更新日期：2018-02-08 00:00:00
abstract：:Anchorage of pedicle screw instrumentation in the elderly spine with poor bone quality remains challenging. In this study, micro finite element (µFE) models were used to assess the specific influence of screw design and the relative contribution of local bone density to fixation mechanics. These were created from micr...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2017.12.023
更新日期：2018-03-21 00:00:00
abstract：:Eight experienced male cyclists (C), eight well-trained male runners (R), and eight less-trained male noncyclists (LT) were tested under multiple cadence and power output conditions to determine: (1) if the cadence at which lower extremity net joint moments are minimized (cost function cadence) was associated with pre...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/s0021-9290(99)00155-4
更新日期：2000-02-01 00:00:00
abstract：OBJECTIVE:Ex vivo studies have suggested that cartilage contact areas and pressure are of high clinical relevance in the etiology of osteoarthritis in patients with patellar subluxation. The aims of this study were therefore to validate in vivo measurements of contact areas with 3D open magnetic resonance imaging (MRI)...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2004.09.008
更新日期：2005-10-01 00:00:00
abstract：:This study analyses the influence of dynamic hydrostatic pressure on chondrogenesis of human meniscus-derived fibrochondrocytes and explores the differences in chondrogenic differentiation under loading conditions between cells derived from the avascular inner zone and vascularized outer region of the meniscus. Aggreg...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2015.02.003
更新日期：2015-06-01 00:00:00
abstract：:This paper describes a method for adjusting biomechanics platform measures of sway for loss of balance. Area and velocity measures of sway were determined in forty-seven elderly women, in double and single leg stance, first with their eyes open, then closed. Subjects were rarely able to complete 10 s trials during sin...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/0021-9290(90)90025-x
更新日期：1990-01-01 00:00:00
abstract：:The analysis of in-field biomechanics data typically requires the identification of foot contact. Existing techniques to identify foot contact using accelerometers offer a viable option for identifying foot contact in the field. However, these techniques often require the placement of additional accelerometers or the ...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2020.109768
更新日期：2020-05-22 00:00:00
