Abstract:
:Older adults may be vulnerable to frontal plane dynamic instability, which is of clinical significance. The purpose of the current investigation was to examine the age-related differences in frontal plane dynamic stability by quantifying the margin of stability and hip abductor moment generation of subjects performing a single crossover step and sidestep to targets that created three different step widths during forward locomotion. Nineteen young adults (9 males, age: 22.9±3.1 years, height: 174.3±10.2cm, mass: 71.7±13.0kg) and 18 older adults (9 males, age: 72.8±5.2 years, height: 174.9±8.6cm, mass: 78.0±16.3kg) participated. For each walking trial, subjects performed a single laterally-directed step to a target on a force plate. Subjects were instructed to "perform the lateral step and keep walking forward". The peak hip abductor moment of the stepping limb was 42% larger by older adults compared to younger adults (p<0.001). Older adults were also more stable than younger adults at all step targets (p<0.001). Older adults executed the lateral step with slower forward-directed and lateral-directed velocity despite similar step widths. Age-related differences in hip abduction moments may reflect greater muscular effort by older adults to reduce the likelihood of becoming unstable. The results of this investigation, in which subjects performed progressively larger lateral-directed steps, provide evidence that older adults may not be more laterally unstable than younger adults. However, age-related differences in this study could also reflect a compensatory strategy by older adults to ensure stability while performing this task.
journal_name
J Biomechjournal_title
Journal of biomechanicsauthors
Hurt CP,Grabiner MDdoi
10.1016/j.jbiomech.2015.01.003subject
Has Abstractpub_date
2015-02-26 00:00:00pages
592-7issue
4eissn
0021-9290issn
1873-2380pii
S0021-9290(15)00005-6journal_volume
48pub_type
杂志文章abstract::Wheelchair-dependent subjects often adopt a passive sitting posture and suffer from sitting acquired pressure ulcers (PU) that mainly occur when high buttock pressures sustain for a longer period of time. Body posture directly influences seating load and proper postural change is therefore essential. Many subjects can...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2008.04.012
更新日期:2008-07-19 00:00:00
abstract::Computational models have the potential to provide precise estimates of stresses and strains associated with sites of coronary plaque rupture. However, lack of adequate mathematical description of diseased human vessel wall mechanical properties is hindering computational accuracy. The goal of this study is to charact...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2011.11.019
更新日期:2012-03-15 00:00:00
abstract::Parallel to the massive use of image-based computational hemodynamics to study the complex flow establishing in the human aorta, the need for suitable experimental techniques and ad hoc cases for the validation and benchmarking of numerical codes has grown more and more. Here we present a study where the 3D pulsatile ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2014.06.017
更新日期:2014-09-22 00:00:00
abstract::2D, coronal plane, finite elements models (FEMs) were developed from orthogonal radiographs of a diaphyseal tibial fracture and its reparative tissue at four different time points during healing. Each callus was separated into regions of common tissue histology by computerised radiographic analysis. Starting point val...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/s0021-9290(99)00189-x
更新日期:2000-04-01 00:00:00
abstract::This study looks at blood flow through four different right coronary arteries, which have been reconstructed from bi-plane angiograms. Five non-Newtonian blood models, as well as the usual Newtonian model of blood viscosity, are used to study the wall shear stress in each of these arteries at a particular point in the...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2003.09.016
更新日期:2004-05-01 00:00:00
abstract::When the foot impacts the ground in running, large forces and loading rates can arise that may contribute to the development of overuse injuries. Investigating which biomechanical factors contribute to these impact loads and loading rates in running could assist clinicians in developing strategies to reduce these load...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2013.10.026
更新日期:2014-01-03 00:00:00
abstract::Experiments were performed to study biaxial anisotropy in relaxed canine carotid arteries subjected to a wide range of longitudinal lengths and transmural pressures. In order to encompass the range of vessel lengths which occurs in situ, 120 carotid arteries were studied at 20%, 40%, 60% and 80% extension relative to ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/0021-9290(86)90011-4
更新日期:1986-01-01 00:00:00
abstract::Atherosclerotic plaque rupture is a major cause of myocardial infarction and ischemic stroke. The adhesive strength of the bond between a plaque and the vascular wall, measured as local energy release rate, G, is used for quantitative plaque stability estimation. We tested the hypothesis that adhesive strength varies ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2012.11.041
更新日期:2013-02-22 00:00:00
abstract::This paper presents a new direct method for estimating the average center of rotation (CoR). An existing least-squares (LS) solution has been shown by previous works to have reduced accuracy for data with small range of motion (RoM). Alternative methods proposed to improve the CoR estimation use iterative algorithms. ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2006.05.010
更新日期:2007-01-01 00:00:00
abstract::Gravity is a contributing force that is believed to influence strongly the control of limb movements since it affects sensory input and also contributes to task mechanics. By altering the relative contribution of gravitational force to the overall forces used to control pedaling at different body orientations, we test...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/0021-9290(96)00038-3
更新日期:1996-10-01 00:00:00
abstract::Establishing the appropriate pressure exerted by the shoe upper over the foot surface is fundamental for the design of specific footwear, although measuring the dorsal pressures can also provide important additional information. In previous works, a virtual simulator to perform studies of comfort and functionality in ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2009.06.054
更新日期:2009-09-18 00:00:00
abstract::This study examined the effect of friction between the hand and grip surface on a person's grip strategy and force generation capacity. Twelve young healthy adults performed power grip exertions on an instrumented vertical cylinder with the maximum and 50% of maximum efforts (far above the grip force required to hold ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2011.03.020
更新日期:2011-05-17 00:00:00
abstract::This study proposed a revision to the Rosenstein's method of numerical calculation of the largest Lyapunov exponent (LyE) to make it more robust to noise. To this aim, the effect of increasing number of initial neighboring points on the LyE value was investigated and compared to values obtained by filtering the time s...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2019.01.013
更新日期:2019-03-06 00:00:00
abstract::This paper addresses the question of whether maximal vertical jump height depends on initial jumping posture. A direct dynamics computer simulation approach was used to avoid subject preference and practice effects. The human body was modeled as four rigid segments connected by ideal hinge joints, with movement constr...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/0021-9290(96)00030-9
更新日期:1996-09-01 00:00:00
abstract::An experimental setup was developed for statically measuring seven vertical and three horizontal reaction forces on the foot. In the setup, the leg can be simultaneously loaded (1) by a vertical force, (2) by an externally applied axial moment, and (3) by simulated muscle forces. The foot is free to invert under influ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/0021-9290(89)90080-8
更新日期:1989-01-01 00:00:00
abstract::The aim of the present study was to develop a Hill type muscle model that accounts for the effects of shortening history. For this purpose, a function was derived that relates force depression to starting length, shortening amplitude and contraction velocity. History parameters were determined from short-range isokine...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/s0021-9290(98)00048-7
更新日期:1998-06-01 00:00:00
abstract::In cementless total hip arthroplasty, osteoporosis may jeopardize the achievement of immediate stability and lead to migration of anatomically shaped femoral stems. Poor quality of proximal cancellous bone per se may also affect the rate of osseointegration. In a selected group of female total hip arthroplasty patient...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2010.10.012
更新日期:2011-01-11 00:00:00
abstract::Previous studies investigating the effects of shoe midsole hardness on running kinematics have often used male subjects from within a narrow age range. It is unknown whether shoe midsole hardness has the same kinematic effect on male and female runners as well as runners from different age categories. As sex and age h...
journal_title:Journal of biomechanics
pub_type: 临床试验,杂志文章
doi:10.1016/j.jbiomech.2012.03.027
更新日期:2012-06-01 00:00:00
abstract::Proper cup alignment is crucial in total hip arthroplasty for reducing impingement risks, dislocations and wear. The Lewinnek "safe zone" is often used in clinical routine. This safe zone does not consider functional aspects and dislocation can occur even when the cup is oriented within the safe zone. Functional safe ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2018.10.020
更新日期:2019-01-03 00:00:00
abstract::There is a growing appreciation of the profound effects that passive mechanical properties, especially the stiffness of the local environment, can have on cellular functions. Many experiments are conducted in a 2D geometry (i.e., cells grown on top of substrates of varying stiffness), which is a simplification of the ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2009.02.012
更新日期:2009-05-29 00:00:00
abstract::The six non-interacting modes for stress, strain and energy in an orthotropic elastic model of human femoral cortical bone tissue are discussed and illustrated. The stress and strain modes are illustrated using the representation of the stress and strain fields around a circular hole in a flat plate of cortical bone s...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/0021-9290(91)90311-a
更新日期:1991-01-01 00:00:00
abstract::Significant ground reaction forces exceeding body weight occur during the heel-strike phase of gait. The standard methods of analytical dynamics used to solve the impact problem do not accommodate well the heel-strike collision due to the persistent contact at the front foot and presence of contact at the back foot. T...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/s0021-9290(00)00006-3
更新日期:2000-06-01 00:00:00
abstract::Bone remodelling is a dynamic process that requires the coordinated interaction of osteocytes, osteoblasts, and osteoclasts, collaborating in basic multicellular units (BMUs). Communication between these cells can be by extracellular soluble molecules as well as directly propagating intercellular signalling molecules....
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2007.02.015
更新日期:2007-01-01 00:00:00
abstract::Osteogenesis imperfecta (OI) is a heritable disease, which results from an abnormal amount or structure of Type I collagen. Bisphosphonates, a class of synthetic antiresorptive drugs, used in osteoporosis management, are also used to decrease fracture incidence and improve quality of life in children with OI. In this ...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2008.09.028
更新日期:2008-12-05 00:00:00
abstract::Vortex shedding at vascular anastomoses were investigated in vitro using a 20 MHz pulsed-wave Doppler velocimeter. Centreline velocity measurements were made at various axial distances in simplified polyurethane models of proximal and distal end-to-side anastomoses of angles 15, 30, 45, 60 and 80 degrees using pulsati...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/s0021-9290(99)00056-1
更新日期:1999-07-01 00:00:00
abstract::Upper extremity musculoskeletal disorders represent an important health issue across all industry sectors; as such, the need exists to develop models of the hand that provide comprehensive biomechanics during occupational tasks. Previous optical motion capture studies used a single marker on the dorsal aspect of finge...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2011.04.003
更新日期:2011-06-03 00:00:00
abstract::Accurate body segment parameter (BSP) information is required for dynamic analyses of motion and the current methods available for obtaining these BSPs have been criticized. The purpose of this study was to determine whether dual energy X-ray absorptiometry (DXA) could accurately measure the BSPs of scanned objects an...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/s0021-9290(02)00227-0
更新日期:2002-12-01 00:00:00
abstract::Aim was to develop an in vivo technique which allows determination of femoro-tibial and of femoro-patellar 3D-kinematics in TKA simultaneously. The knees of 20 healthy volunteers and of eight patients with TKA (PCR, rotating platform) were investigated. Kinematics analysis was performed in an open MR-system at differe...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2007.03.020
更新日期:2007-01-01 00:00:00
abstract::Locations, magnitudes, and directions of pelvic muscle and acetabular contact forces are important to model the effects of abnormal conditions (e.g., deformity, surgery) of the hip accurately. Such data have not been reported previously. We computed the three-dimensional locations of all pelvic muscle and acetabular c...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/s0021-9290(97)00041-9
更新日期:1997-09-01 00:00:00
abstract::Sphenodon, a lizard-like reptile, is the only living representative of a group that was once widespread at the time of the dinosaurs. Unique jaw mechanics incorporate crushing and shearing motions to breakdown food, but during this process excessive loading could cause damage to the jaw joints and teeth. In mammals li...
journal_title:Journal of biomechanics
pub_type: 杂志文章
doi:10.1016/j.jbiomech.2010.08.001
更新日期:2010-12-01 00:00:00