Remo H. Largo

Neuromotor development from 5 to 18 years. Part 1: timed performance

Timed performance in specific motor tasks is an essential component of a neurological examination applied to children with motor dysfunctions. This article provides centile curves describing normal developmental course and interindividual variation of timed performances of non-disabled children from 5 to 18 years. In a cross-sectional study (n=662) the following motor tasks were investigated: repetitive finger movements, hand and foot movements, alternating hand and foot movements, sequential finger movements, pegboard, and dynamic and static balance. Intraobserver, interobserver, and test-retest reliability for timed measurements were moderate to high. Timed performances improved throughout the entire prepubertal period, but differed among various motor tasks with respect to increase in speed and when the adolescent plateau was reached. Centile curves of timed performance displayed large interindividual variation for all motor tasks. At no age were clinically relevant sex differences noted, nor did socioeconomic status significantly correlate with timed performance. Our results demonstrate that timed motor performances between 5 and 18 years are characterized by a long-lasting developmental change and a large interindividual variation. Therefore, a well standardized test instrument, and age-specific standards for motor performances are necessary preconditions for a reliable assessment of motor competence in school-age children.

Neuromotor development from 5 to 18 years. Part 2: associated movements.

Associated movements (AMs) are the most frequently assessed parameters of movement quality in children with motor dysfunctions. In this article, reference curves of duration and degree of AMs from 5 to 18 years are provided. In a cross-sectional study of non-disabled children (n=662) duration and degree of AMs were estimated at six specific ages while children performed repetitive finger, hand, and foot movements, alternating hand and foot movements, diadochokinesis, sequential finger movements, pegboard, stress gaits, and dynamic balance. Moderate-to-high intraobserver and interobserver reliability for the assessment of AMs were noted. Duration and degree of AMs displayed a non-linear developmental course that was a function of the motor tasks complexity. AMs decreased most with age in repetitive movements, less in alternating and sequential movements, and least in the pegboard and dynamic balance. Reference curves demonstrated large interindividual variations for duration and degree of AMs. Both the variable developmental course and large interindividual variation need to be taken into account in the assessment of movement quality of school-age children. In contrast to timed performance, considerable sex differences for AMs were observed.

Developmental Progression in Play Behavior of Children between Nine and Thirty Months. I: Spontaneous Play and Imitation

The developmental progression of play behavior was studied cross‐sectionally in 85 children at eight age‐levels between nine and 30 months. In a structured play situation, three major play patterns were distinguished: (1) exploratory play (at the end of the first year); (2) functional play (beginning of second year); and (3) representational play (after 15 months). Sequential play first occurred at 21 months. Play behavior with spatial characteristics was also observed: relational and container play between nine and 15 months, and understanding of spatial relationships, stacking and grouping between 18 and 24 months.

Impaired motor performance and movement quality in very-low-birthweight children at 6 years of age

Motor performance and movement quality were quantitatively examined (Zurich Neuromotor Assessment: timed motor performances and associated movements) in 87 prospectively enrolled very-low-birthweight (VLBW; <1250g) children (38 males, 49 females; mean birthweight 1016.2g [SD 141.5]:, range 720-1240g; mean gestational age 28.7wks [SD 2], range 25.7-33.4wks) at 6 years of age. All motor tasks were below the reference population: pure motor (median z-score) -0.46; adaptive fine motor (pegboard) -0.99; adaptive gross motor -0.88; static balance -0.48; and associated movements -1.90. All tasks correlated with the degree of neurological abnormalities (p<or=0.004). VLBW children with no neurological abnormality also performed below the 10th centile and associated movements occurred more frequently than in the reference population (odds ratio 18, 95% confidence interval 6.7-47.9). Severity of periventricular leukomalacia and intraventricular haemorrhage assessed by ultrasound was associated with adaptive fine and gross motor tasks. We conclude that speed of motor performance and movement quality in particular were substantially impaired in VLBW children and are related to the degree of neurological abnormalities and neonatal cerebral injury.

Longitudinal study of bowel and bladder control by day and at night in the first six years of life. I: Epidemiology and interrelations between bowel and bladder control.

The development of bowel and bladder control by day and at night during the first six years of life in 320 Swiss children in the Zurich longitudinal study (1955–1976) is described in detail. A scoring system was used which included intermediate stages of control. With toilet‐training started in 96 per cent of the children during the first year of life, bowel control was completed in 32 per cent at age one, in 75 per cent at age two and in 97 per cent at age three. Complete bladder control by day and at night were established in none of the children at age one, in 20 per cent at ages two and three and in 90 per cent at age four. Complete bowel control and complete bladder control by day and at night were found in 5 per cent at age two, in 11 per cent at age three, in 77 per cent at age four and in 91 per cent at age six.

Does a profound change in toilet-training affect development of bowel and bladder control?

A major change in toilet‐training was observed in two successive generations. The median onset of toilet‐training was postponed by 13 months between the First Zürich Longitudinal Study (320 children born between 1954 and 1956) and the Second Zurich Longitudinal Study (309 children bom between 1974 and 1984). Bladder control, both day and night, was not affected, but bowel control was delayed by 16 months, due not to a lack of training, but to the abandonment of maternal control. The results strongly confirm earlier findings that the development of bowel and bladder control is a maturational process which cannot be accelerated by early onset and high intensity of potty‐training. The childs initiative proved to be a reliable indicator that the child was developmentally capable of being clean and dry. Girls were consistently earlier than boys. indicating different maturation rates. No significant correlations were noted between the socioeconomic status and start and intensity of toilet‐training, onset of the childs initiative or development of bladder and bowel control.

Development of bladder and bowel control: significance of prematurity, perinatal risk factors, psychomotor development and gender.

Abstract Development of bladder and bowel control from 6 months to 6 years was investigated in 140 preterm children and a control group of 349 healthy term children. Structured parental interviews and neurodevelopmental assessments were carried out when the child was 1, 3, 6, 9, 12, 18 and 24 months, and at yearly intervals thereafter. Even though preterm children were put on the potty at significantly earlier ages and significantly more frequently than term children, they expressed their need for evacuation and attained day and night bladder and bowel control at the same corrected age as term children. Initiation and intensity of toilet-training were not significantly correlated with the development of bladder and bowel control. Gestational age, being too small for gestational age, adverse perinatal conditions and mild to moderate neurological impairment did not affect the occurrence of the childs initiative and the development of bladder and bowel control. Neither developmental and intelligence quotients at the age of 1 to 3 years nor the socioeconomic status of the families influenced the age at which the child became clean and dry. Girls were significantly more advanced in expressing their needs and gaining bladder and bowel control than boys in both the preterm and term groups. nConclusion Development of bladder and bowel control is largely a maturational process which cannot be accelerated by an early onset or a high intensity of training. It is not affected by prematurity, adverse perinatal events or mild to moderate neurological impairment, nor is it related to psychomotor development or actual Swiss socioeconomic conditions.

Sleep behaviour in preterm children from birth to age 10 years: A longitudinal study

Aim: To study clinically relevant aspects of sleep behaviour in preterm children in comparison to term children. Methods: Longitudinal sleep behaviour data were collected prospectively by structured interviews in 130 preterm and 75 control term children from birth to age 10 y. Results: No significant differences in sleep duration (time in bed per 24 h), bedsharing, night wakings, bedtime resistance and sleep‐onset difficulties were found between preterm and term children.

Longitudinal study of bowel and bladder control by day and at night in the first six years of life. II: The rôle of potty training and the child's initiative.

The rôle of potty training and the childs own initiative to use the pot were evaluated in 320 Swiss children in the Zurich longitudinal study (1955–1976). Initiating potty training in the first months of life has a short‐term effect on bowel control, but no effect on bladder control by day or at night. Frequent daily prompting to use the pot results in a higher percentage of completely bowel‐trained children, and of children partially but not completely dry during the day. It has no influence on bladder control at night.

Differences in Movement Quality at Term among Preterm and Term Infants

Significant differences in movement quality at term are reported in high-risk preterm (n = 18), low-risk preterm (n = 21) and term (n = 20) infants. Movement quality was judged using 2-minute video collection of general movements; three parameters of movement quality could be assessed reliably in a semiquantitative way: fluency, spatiotemporal variability and sequencing. The parameters fluency and variability correlated highly with each other (r = 0.47-0.99) while their correlations with sequencing were less (r = 0.42-0.67). Significant differences on all quality parameters were noted between term, low-risk preterm and high-risk preterm infants (p < 0.001-0.05). The findings indicate a significant impact of prematurity per se and brain damage on movement quality.