Gait in Very Preterm School-Aged Children in Dual-Task Paradigms

Early spontaneous movements and spatiotemporal gait characteristics in preterm children

This study aimed to analyze spatiotemporal gait characteristics of preterm children from 3 to 4 years of age according to different gestational age groups and to examine the relationship between the detailed general movements assessment and spatiotemporal gait characteristics. A total of 74 preterm children, 32 extremely preterm and very preterm (EP-VP, < 32 weeks gestational age) and 42 moderate to late preterm (MLP, 32 to < 37 weeks gestational age), were included in this prospective study, along with 38 term children. Early spontaneous movements of preterm children were assessed from videos at 9-20 weeks post-term according to the general movements assessment, which determines the Motor Optimality Score-Revised (MOS-R). The spatiotemporal gait characteristics of all children were evaluated using the GAITRite^®electronic walkway at self-selected walking speeds. EP-VP children walked with shorter step lengths (p = 0.039), and MLP children walked with greater step length variability (p = 0.003) than their term peers. The MOS-R results were related to step length (r = 0.36, p = 0.042), step length variability (r =  -0.56, p = 0.001), and base of support (r =  -0.37, p = 0.038) in EP-VP children. The MOS-R subcategories, age-adequate movement repertoire, and postural patterns were related to some of the spatiotemporal gait characteristics, including step length, step length variability, and base of support (p < 0.05).  Conclusion: EP-VP and MLP children might catch up to their term peers at 3 to 4 years of age in terms of most gait parameters. In addition to the MOS-R, age-adequate movement repertoire and postural patterns of preterm children without cerebral palsy in early life may be a marker of later neurodevelopmental dysfunction. What is Known: • Preterm children walk with a wider step width, a greater step length asymmetry and step time, and a shorter stride length at 18 to 22 months of age compared with term children at a self-selected speed, while these differences disappear in children 4.5-5 years old and older. What is New: • Early spontaneous movements were related to some spatiotemporal gait characteristics. • Preterm children might catch up to term children at 3-4 years of age in spatiotemporal gait characteristics while walking at a self-selected speed.

Gait performance in toddlers born preterm: A sensor based quantitative characterization

BACKGROUND AND OBJECTIVES

Preterm children have an increased risk of motor difficulties. Gait analysis and wearable technologies allow the assessment of motor performance in toddlers, identifying early deviations from typical development. Using a sensor-based approach, gait performance of full-term and preterm toddlers at different risk of motor delay was analysed. The aim was to measure quantitative differences among groups.

METHODS

Twenty-nine two-year old children born preterm (≤36 gestational weeks) and 17 full-term controls, matched for age and walking experience, participated in the study. Preterm children were further divided based on risk of motor delay: preterm at high risk (n = 8, born at ≤28 gestational weeks or with ≤1000 g of body weight), and at moderate risk (n = 21). Children were asked to walk along a corridor while wearing 3 inertial sensors on the lower back and on the ankles. Gait temporal parameters, their variability, and nonlinear metrics of trunk kinematics (i.e. recurrence quantification analysis, multiscale entropy) were extracted from the collected data and compared among groups.

RESULTS

Children born preterm showed significantly longer stance and double support phases, higher variability of temporal parameters, and lower multiscale entropy values than peers born full-term. No difference was found for the other parameters when comparing preterm and full-term children. When comparing children grouped according to risk of delay, with increasing risk, children showed longer stride-, stance- and double-support-time, higher variability of temporal parameters, higher recurrence- and lower multiscale entropy values.

CONCLUSIONS

Sensor-based gait analysis allowed differentiating the gait performance of preterm from full-term toddlers, and of preterm toddlers at different risk of motor delay. When analysing the present results with respect to the expected trajectory of locomotor development, children born preterm, in particular those at higher risk of motor delay, exhibited a less mature motor control performance during gait: lower stability (i.e. longer support phases), and higher variability, although not structured towards the exploration of more complex movements (i.e. higher recurrence- and lower multiscale entropy values). These indexes can serve as biomarkers for monitoring locomotor development and early detecting risk to develop persistent motor impairments.

Spatiotemporal gait variables and step-to-step variability in preschool-aged children born < 30 weeks' gestation and at term in preferred speed, dual-task paradigm, and tandem walking

BACKGROUND

Children born very preterm (< 32 weeks' gestation) are at greater risk of motor impairment and executive/attentional dysfunctions than term-born children; however, little is known about how functional tasks, including walking, may be affected by very preterm birth.

RESEARCH QUESTION

How does the gait pattern of preschool-age children born < 30 weeks compare with term-born controls under a variety of walking conditions?

METHODS

In this prospective cohort study, children born < 30 weeks and at term were assessed at 4.5-5 years' corrected age, blinded to birth group. Four walking conditions were assessed using the GAITRite® system: preferred speed, cognitive dual-task, motor dual-task, and tandem walking. Gait variables analysed included speed, cadence, step length, step time, base of support (BOS), and single and double support time. Spatiotemporal variables were compared between groups using linear regression, adjusting for lower-limb length, corrected age at assessment, and number of trials.

RESULTS

224 children (112 < 30 weeks and 112 term-born) were assessed. Gait variables of children born < 30 weeks did not differ from their term-born peers when walking at their preferred speed, except for higher BOS variability (mean difference [MD] = 0.19 cm, 95% confidence interval [CI] 0.10, 0.27, p < 0.001). Under the motor dual-task condition, children born < 30 weeks walked faster (MD= 3.06 cm/s, 95% CI 0.14, 5.97, p = 0.040), with a longer step length (MD= 1.10 cm, 95%CI 0.19, 2.01, p = 0.018), and a wider BOS (MD= 0.37 cm, 95%CI 0.06, 0.67, p = 0.019). In cognitive dual-task and tandem conditions, children born < 30 weeks walked with a wider BOS compared with term-born peers (MD= 0.43 cm, 95%CI 0.05, 0.81, p = 0.028; and MD= 0.30 cm, 95%CI 0.09, 0.51, p = 0.005, respectively).

SIGNIFICANCE

This research highlights the need to consider the walking performance of preschool-age children born < 30 weeks under challenging conditions, such as dual-task or tandem walking, when assessing gait patterns and planning interventions.

Physical functions and gait performance in school-aged children born late preterm

BACKGROUND

Children born late preterm (LP) have an increased risk of poor developmental motor outcomes.

AIMS

This study aimed to assess physical functions and gait performance in school-aged children born LP.

STUDY DESIGN

Cross-sectional study.

SUBJECTS

Physical functions and gait performance were evaluated in 277 children aged 6-10 years born LP (n = 22) and full-term (FT) (n = 255).

OUTCOME MEASURES

Physical function tests consisted of five times sit-to-stand test (FTSST), one-leg standing time, and grip strength. FTSST was used to assess the functional muscle strength of the lower limbs and dynamic balance function. Gait performance tests included gait quality, spatiotemporal gait parameters, and gait variability. Clinical data, physical functions, and gait performance were compared between two groups. Furthermore, logistic regression analysis was performed to assess the association between all variables and LP birth.

RESULTS

In physical function tests, children born LP showed poorer FTSST than those born FT (p = 0.039). No significant difference in gait performance tests were identified between the two groups. Logistic regression analysis of FTSST for LP (adjusted for age at assessment) revealed that FTSST was significantly associated with LP birth (p = 0.004, odds ratio = 1.579, 95% confidence interval = 1.160-2.149).

CONCLUSIONS

We demonstrated the physical functions and gait performance in school-aged children born LP. Our findings indicate that it is important to focus on the decreased functional muscle strength of the lower limbs and reduced dynamic balance function related to LP birth to improve functional mobility in children born LP.

Working memory is a core executive function supporting dual-task locomotor performance across childhood and adolescence

Most daily-life ambulatory tasks involve dual tasking, for example, talking while walking. In children, the evidence supporting the effects of age on dual tasking is confounded by the difficulty of the cognitive task and lack of adjustment to suit individual cognitive abilities. To address this issue, the current study examined the effects of age, cognitive load, and executive functioning on the degree of dual-task gait interference across childhood and adolescence. We tested 120 typically developing children aged 6-11 years, adolescents aged 12-16 years, and young adults aged 18-25 years. Participants were asked to walk while performing a visuospatial working memory task at two levels of cognitive load (easy and difficult) adjusted to suit each participant's cognitive ability. Spatiotemporal characteristics and intra-individual variability of gait were measured using a GAITRite electronic walkway. Irrespective of the cognitive load level, children aged 6 to 11 years showed greater dual-task gait interference for selective spatiotemporal gait characteristics; however, the younger children showed a trade-off pattern in gait variability whereby they prioritized gait stability at the expense of cognitive performance. Our results also showed that age and working memory capacity were significant predictors of dual-task interference for a range of complementary gait parameters in the combined sample. Importantly, working memory capacity was part of a moderating relationship between age and dual-task gait interference. These findings emphasize the importance of dual-task prioritization strategies in younger children and highlight the role of individual differences in working memory capacity in performance in dual-task gait situations.

Using a dual-task paradigm to investigate motor and cognitive performance in children with intellectual disability

BACKGROUND

The purpose of the current study was to evaluate the effects of dual-task (DT) constraints on walking performance in children with intellectual disability (ID).

METHODS

Fifteen children with intellectual disability and fifteen age-matched typically developed children were asked to walk at a preferred speed: along a path (baseline condition), while carrying a glass of water and while quoting animal names.

RESULTS

The present study findings showed that DTs affect walking performance of both typically developed children and those with intellectual disability. In children with intellectual disability, DT walking decrements were significantly higher when performing a concurrent motor task than cognitive one.

CONCLUSIONS

DT constraints with a secondary motor or cognitive tasks seemed challenging for children with intellectual disability suggesting that future treatments or assessments should consider using DT constraints to manipulate the difficulty of tasks.

Analysis of infant physical activity in the childcare environment: An observational study

This study utilized behavior-mapping to describe behavior and levels of activity in infants attending Early Childhood Education and Care (ECEC). Descriptive statistics were used to determine proportion of time spent in certain locations, body positions, activities and engagement with others. To establish whether location, the presence of equipment or engagement with others influenced levels of activity, a paired t-test was used. Results indicated that of all locations, infants spent the greatest amount of time in the meals area (35%), with half of this period spent physically inactive (sedentary). The indoor play area was where infants were most active. Infants also spent a significantly greater proportion of their upright time (64%) supported by either furniture or equipment than without (MD 28, 95% CI 13-44, p < 0.01). Interestingly, infants displayed more sedentary behavior when engaged with others than when not engaged (MD 21, 95% CI 6-36, p < 0.01). The environment, presence of others and equipment availability appear to influence activity levels of infants in ECEC centers. Findings suggest that time spent in meal areas, provisions of furniture/equipment, and opportunities for infants to play independently warrant further exploration to determine their influence on activity levels in typically-developing infants.

Gait Characteristics of Children Born Preterm

Walking is a central skill of daily living. A delay in the onset of walking can be a sign of abnormal motor development. Further, abnormalities in gait can also affect physical functioning. Children born preterm are at significant risk for neurodevelopmental impairments; however, little is known about how preterm birth affects walking. This review describes current evidence of walking in children born preterm with a focus on the age at onset of walking and comparisons of gait characteristics of children born preterm with those born full-term.

The association between sleep and dual-task performance in preterm and full-term children: an exploratory study

OBJECTIVES

The present study explored associations between sleep and children's dual-task performance using cognitive-motor dual tasks (eg, walking and talking). Previous research with older adults indicated correlations between higher gait variability and unfavorable sleep continuity variables. Based on this research, as a first objective, we investigated similar correlations in a sample of children. Second, we explored correlations between dual-task performance and dimensions of sleep architecture. Third, we tested moderating effects of prematurity on these associations.

METHODS

In this study, 7-to 12-year-old children were tested in dual-task situations; of those, 39 were formerly preterm, and 59 were full-term born children. They were asked to walk and simultaneously perform different cognitive tasks. Gait was measured using an electronic walkway system. Sleep was measured using in-home sleep-electroencephalography.

RESULTS

After accounting for age and cognition, regression analyses revealed correlations between a higher number of awakenings after sleep onset and lower dual-task performance; concerning sleep architecture, analyses revealed correlations between a higher amount of rapid-eye-movement (REM) sleep and lower gait variability. Furthermore, associations between a higher amount of slow wave sleep (SWS) and children's higher cognitive performance were found. Moderation analyses indicated no effects of prematurity.

CONCLUSIONS

Our exploratory study suggests that a more disrupted sleep was related to children's poorer dual-task performance. Our findings support claims that REM sleep seems more related to performance in procedural tasks whereas SWS seems more related to performance in declarative tasks, suggesting that different sleep stages may support the processing of different performance types.

Temporal frequency discrimination in amblyopia

The present study aimed to explore temporal frequency discrimination in amblyopia, and the influence of attentional load on amblyopic temporal cognition. Twenty anisometropic amblyopes, 20 strabismic amblyopes and 20 normal subjects were recruited. A flickering disk was used for visual stimuli. A two-alternative, forced-choice staircase paradigm was used to measure the temporal frequency discrimination thresholds of amblyopic eyes, fellow eyes and normal dominant eyes under reference temporal frequencies of 5, 10 and 20 Hz. The just-noticeable differences data were analyzed statistically. In addition, the temporal frequency discrimination thresholds of the subjects were measured under different conditions of attentional load. The changes in temporal frequency discrimination thresholds were compared between amblyopic and normal eyes when attention was loaded. At the reference temporal frequencies of 5 and 10 Hz, temporal thresholds of amblyopic eyes were significantly increased compared with fellow eyes (P<0.05). Regarding strabismic amblyopia, temporal thresholds of fellow eyes were increased compared with normal eyes (P<0.05). However, no correlation was identified between the temporal-frequency discrimination thresholds and the LogMAR visual acuities in amblyopic eyes. In addition, higher attentional load caused greater changes in temporal thresholds in amblyopic eyes, but the situation was not the same for lower attentional load. In conclusion, in the present study a deficit of temporal frequency discrimination in amblyopic eyes and the fellow eyes of strabismic amblyopes was identified. Furthermore, the influence of attentional load on temporal frequency discrimination in amblyopic eyes was increased compared with normal eyes.

Quantification of gait in children with mitochondrial disease

Mitochondrial disorders are multisystem conditions that can potentially affect gait in many ways. The aim of this study was to select the optimal protocol to quantify the spatiotemporal parameters of gait in ambulatory children with mitochondrial disorders based on feasibility, test-retest reliability, and the difference between patients and controls. Gait at self-selected pace was quantified in ambulatory children with a genetically confirmed primary mitochondrial disease using the GAITRite electronic walkway. Three protocols were tested: pre-exercise, post-exercise (after a 3-min walking test), and recovery. In 14 ambulatory patients, we showed good to perfect reliability for velocity, cadence, step length, step time, step time variability, and step width in the recovery condition. The difference between patients and 70 individually age- and gender matched healthy controls only became apparent in the post-exercise protocol. In conclusion, measuring spatiotemporal parameters of gait using the GAITRite in ambulatory children with mitochondrial disease is feasible and reliable for most of the parameters measured. When using gait analysis in future studies in children with mitochondrial disease, we advise i) to use an exercise test prior to the gait analysis, ii) to let children practice the test before the actual data collection, and iii) not to use symmetry parameters.

Gait in Children with Attention-Deficit Hyperactivity Disorder in a Dual-Task Paradigm

The aim was to examine gait in school-aged children with attention-deficit hyperactivity disorder (ADHD) and typically developing controls in a dual-task paradigm. Thirty children with ADHD (without or off medication) aged 7-13 years and 28 controls walked without an additional task (single-task walking) and while performing a concurrent cognitive or motor task (dual-task walking). Gait was assessed using GAITRite recordings of spatiotemporal and variability gait parameters. Compared to single-task walking, dual-tasking significantly altered walking performance of children with and without ADHD, whereby dual-task effects on gait were not different between the two groups. For both children with ADHD and controls the motor concurrent task had a stronger effect on gait than the cognitive concurrent task. Gait in children with and without ADHD is affected in a dual-task paradigm indicating that walking requires executive functions. Future investigations of children's dual-task walking should account for the type of concurrent tasks.

Walking in School-Aged Children in a Dual-Task Paradigm Is Related to Age But Not to Cognition, Motor Behavior, Injuries, or Psychosocial Functioning

Age-dependent gait characteristics and associations with cognition, motor behavior, injuries, and psychosocial functioning were investigated in 138 typically developing children aged 6.7-13.2 years (M = 10.0 years). Gait velocity, normalized velocity, and variability were measured using the walkway system GAITRite without an additional task (single task) and while performing a motor or cognitive task (dual task). Assessment of children's cognition included tests for intelligence and executive functions; parents reported on their child's motor behavior, injuries, and psychosocial functioning. Gait variability (an index of gait regularity) decreased with increasing age in both single- and dual-task walking. Dual-task gait decrements were stronger when children walked in the motor compared to the cognitive dual-task condition and decreased with increasing age in both dual-task conditions. Gait alterations from single- to dual-task conditions were not related to children's cognition, motor behavior, injuries, or psychosocial functioning.