Biomedical subjects

Victoria L Chester

Publications and source records attributed to Victoria L Chester.

4 recordsLinked to original sources

PubMed2006

An extended index to quantify normality of gait in children.

Clinical gait analysis aims to quantify and assess the mechanics of walking and identify deviations from 'normal' movement patterns. To facilitate the use of clinical equipment, protocols are required to process data and produce a few meaningful summary measurements which can, in turn, be used to flag gait abnormalities. Earlier work produced a one-dimensional index of gait, calculated from sagittal hip, knee and ankle rotation angle patterns. The objective of this study was to extend the original index, incorporating kinematic and kinetic data from multiple planes, while allowing for correlations between component measures. A one-dimensional index of normal gait was developed, based on normative gait data (N=45 children, aged 3-13 years). The new one-dimensional index was calculated using correlation patterns between seven component indices, each of which has diagnostic interpretation. The effectiveness of the new index was tested using immature normative data (N=14) and hypotonic data (N=10). Approximately 85% of immature normative children and 100% of hypotonic children were classified as either unusual or extreme by the one-dimensional index. These data reduction protocols improve objective gait analyses in the clinical setting.

Adolescent↗

PubMed2006

A comparison of kinetic gait parameters for 3-13 year olds.

BACKGROUND: Normative gait data is essential for diagnosing and treating abnormal gait patterns. The examination of the onset of adult-like kinetic gait patterns in children has generated inconsistent results. The purpose of this study was to identify age-related differences in kinematic and kinetic gait parameters across children aged 3-13 years old. METHODS: A motion capture system and three force plates were employed to compute sagittal joint angles and joint kinetics during walking and compare results between children aged 3-4 years (n=13), 5-6 years (n=10), 7-8 years (n=12), and 9-13 years (n=12). Anthropometric data was estimated using a mathematical model (elliptical cylinder method). Peak flexion and extension joint angles and moments, and peak concentric and eccentric joint powers were analyzed using multivariate analyses of variance. FINDINGS: For most of the variables examined, similar results were obtained across age groups. Reduced peak hip flexion moments and knee extension moments were observed in the 3-4 year olds compared to the oldest group of walkers. Compared to the 9-13 year olds, reduced ankle joint moments and power were observed in most age groups. INTERPRETATION: The results suggest that adult-like kinetic patterns for the hip and knee were attained by 5 years of age. However, for the ankle joint, adult-like patterns are not achieved until nine years of age or older. These findings stress the importance of using age-matched normative data for clinical gait analysis.

Adolescent↗

PubMed2005

Changes in infant segment inertias during the first three months of independent walking.

BACKGROUND: During infancy, rapid changes in physical growth affect the size and shape of the body segments. To understand the effects of growth on movement, it is first necessary to quantify rates of development during the acquisition of important motor milestones. The goal of this longitudinal study was to quantify the physical growth of infant body segments during the initial stages of independent walking. METHODS: Ten infants (N = 10) aged between 28 and 55 weeks at the beginning of the study were tested biweekly (every two weeks) for three months. A 13-segment mathematical model of the human body was used to estimate the inertial parameters of the infant body segments at each session. An analysis of variance was used to test for significant differences in segment masses between biweekly measures. Polynomial contrasts were used to test for linear trends in the growth data. RESULTS: Significant differences between biweekly measures of segment mass were found only for the head/neck (F(5,45) = 3.42, p < 0.05), upper trunk (F(5,45) = 4.04, p < 0.01), and lower trunk (F(5,45) = 3.49, p < 0.01). The lower trunk demonstrated a linear increase in mass (F(1,9) = 4.56, p < 0.05). However, the upper trunk demonstrated a quadratic trend in growth (F(1,9) = 9.13, p < 0.01), while the head/neck segment showed a cubic trend in growth (F(1,9) = 3.80, p < 0.05). Significant differences in axial segment masses were also found between subjects (F(9,45) = 5.92, p < 0.001). CONCLUSION: Given that postural control proceeds in a cephalocaudal manner, the lower trunk segment would be brought under control last, in terms of the axial segments. Increases in the mass of this segment could constrain the system, thereby acting as a control parameter for the onset and development of motor patterns.

Journal Article↗

PubMedDate not supplied

Gait analysis.

Gait analysis, or the study of locomotion, has changed dramatically over the last few decades. Advances in computer technology and data analysis techniques have contributed greatly to the progress of this field. Gait analysis has become a valuable tool in the clinical setting. The ability to objectively quantify motion is essential to our understanding of normal and abnormal movement patterns and the evaluation of treatment effectiveness. This paper will discuss the various experimental and analytical techniques currently used for performing clinical gait analyses at the University of New Brunswick, Fredericton, New Brunswick, Canada.

Equipment Design↗