There is limited research that directly compares the effect of reduced speed with reduced propulsive force production (PFP) on age-related gait changes. We aimed to determine how changes in the gait of older adults correlate with age, speed, or peak PFP over a 6-year span. We collected kinematics and kinetics of 17 older subjects at 2 time points.
View Article and Find Full Text PDFMaintenance of postural control is a complex task that requires the integration of different sensory-motor processes. To improve postural control, balance training is often implemented using unstable surfaces. Little is known, however, about how different surfaces compare in terms of postural control strategy.
View Article and Find Full Text PDFClin Biomech (Bristol)
October 2021
Background Cervical collar treatment is widespread amongst a broad range of ages and conditions. However, these devices are associated with a known correlation between collar usage and adverse effects such as pressure ulcers, infections, exacerbated spinal injury, and higher morbidity. The objective of this study was to determine if the ability of a newly developed DJO Procare XTEND 174 collar to restrict cervical spine motion was similar to that of the previously studied Össur Miami J collar and to determine if this was done while producing similar tissue interface pressures.
View Article and Find Full Text PDFDespite continuing advances, nearly 20% of patients remain dissatisfied with their total knee arthroplasty (TKA) outcomes. Single-radius (SR) and multiradius (MR) TKA designs are two commonly used knee replacement designs based on competing theories of the flexion/extension axis of the knee. Our aim was to characterize stair descent kinematics and kinetics in SR and MR TKA subjects.
View Article and Find Full Text PDFSample entropy (SE) has relative consistency using biologically-derived, discrete data >500 data points. For certain populations, collecting this quantity is not feasible and continuous data has been used. The effect of using continuous versus discrete data on SE is unknown, nor are the relative effects of sampling rate and input parameters (comparison vector length) and (tolerance).
View Article and Find Full Text PDFMed Biol Eng Comput
April 2019
Sample entropy (SaEn) has been used to assess the regularity of lower limb joint angles during walking. However, changing sampling frequency and the number of included strides can potentially affect the outcome. The present study investigated the effect of sample frequency and the number of included strides on the calculations of SaEn in joint angle signals recorded during treadmill walking.
View Article and Find Full Text PDFTraditionally total knee arthroplasty (TKA) design has been based on theories of the movement of the healthy knee joint. Currently, there are two competing theories on the flexion/extension axis of rotation of the knee with disparate radii of rotation, and thus differing movement patterns. The purpose of our study was to compare stair ascent kinematics and kinetics of single-radius (SR) and multiradius (MR) TKA subjects.
View Article and Find Full Text PDFPatients with peripheral artery disease (PAD) experience significant leg dysfunction. The effects of PAD on gait include shortened steps, slower walking velocity, and altered gait kinematics and kinetics, which may confound joint torques and power measurements. Spatiotemporal parameters, joint torques and powers were calculated and compared between 20 patients with PAD and 20 healthy controls using independent t-tests.
View Article and Find Full Text PDFIt is sometimes difficult to obtain uninterrupted data sets that are long enough to perform nonlinear analysis, especially in pathological populations. It is currently unclear as to how many data points are needed for reliable entropy analysis. The aims of this study were to determine the effect of changing parameter values of m, r, and N on entropy calculations for long gait data sets using two different modes of walking (i.
View Article and Find Full Text PDFThe aim of this investigation was to compare and contrast the use of cross sample entropy (xSE) and cross recurrence quantification analysis (cRQA) measures for the assessment of coupling of rhythmical patterns. Measures were assessed using simulated signals with regular, chaotic, and random fluctuations in frequency, amplitude, and a combination of both. Biological data were studied as models of normal and abnormal locomotor-respiratory coupling.
View Article and Find Full Text PDFObjective: Previous studies have indicated that patients with peripheral artery disease (PAD), display significant differences in their kinetic and kinematic gait characteristics when compared to healthy, aged-matched controls. The ability of patients with chronic obstructive pulmonary disease (COPD) to ambulate is also limited. These limitations are likely due to pathology-driven muscle morphology and physiology alterations establish in PAD and COP, respectively.
View Article and Find Full Text PDFAccumulating evidence suggests revascularization of peripheral arterial disease (PAD) limbs results in limited improvement in functional gait parameters, suggesting underlying locomotor system pathology. Spatial and temporal (ST) gait parameters are well studied in patients with PAD at baseline and are abnormal when compared to controls. The purpose of this study was to systematically review and critically analyze the available data on ST gait parameters before and after interventions.
View Article and Find Full Text PDFBackground: The present study aimed at devising a data processing procedure that provides an optimal estimation of the 3-D instantaneous orientation of an inertial measurement unit (IMU). This result is usually obtained by fusing the data measured with accelerometers, gyroscopes, and magnetometers. Nevertheless, issues related to compensation of integration errors and high sensitivity of these devices to magnetic disturbances call for different solutions.
View Article and Find Full Text PDFThis study introduces a new method of extracting initial and final contact gait time events from vertical acceleration, measured with one waist mounted inertial measurement unit, by means of continuous wavelet transforms. The method was validated on 18 young healthy subjects and compared to two others available in the literature. Of the three methods investigated, the new one was the most accurate at identifying the existence and timing of initial and final contacts with the ground, with an average error of 0.
View Article and Find Full Text PDFThe aim of this study was the fine tuning of a Kalman filter with the intent to provide optimal estimates of lower trunk orientation in the frontal and sagittal planes during treadmill walking at different speeds using measured linear acceleration and angular velocity components represented in a local system of reference. Data were simultaneously collected using both an inertial measurement unit (IMU) and a stereophotogrammetric system from three healthy subjects walking on a treadmill at natural, slow and fast speeds. These data were used to estimate the parameters of the Kalman filter that minimized the difference between the trunk orientations provided by the filter and those obtained through stereophotogrammetry.
View Article and Find Full Text PDFSeveral surgical approaches for total knee arthroplasty (TKA) have been developed to minimize soft-tissue trauma and expedite functional recovery. A group of 61 subjects undergoing computer-navigated, minimally invasive TKA were randomized to receive a mini-parapatellar, standard parapatellar, mini-midvastus (MV), or mini-subvastus approach. Before and after treatment, subjects were asked to negotiate stairs in a self-selected manner.
View Article and Find Full Text PDFA reproducible retroacetabular defect was created bilaterally in 9 cadaver pelves. The defects were filled with either an injectable, bioresorbable, calcium phosphate cement, or reverse-reamed cancellous allograft. An uncemented acetabular shell was impacted, followed by the placement of an appropriate liner.
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