Hua-Fang Liao

Effectiveness of Loaded Sit-to-Stand Resistance Exercise for Children With Mild Spastic Diplegia: A Randomized Clinical Trial

Abstract Liao H-F, Liu Y-C, Liu W-Y, Lin Y-T. Effectiveness of loaded sit-to-stand resistance exercise for children with mild spastic diplegia: a randomized clinical trial. Objective To investigate effectiveness of a functional strengthening program, the loaded sit-to-stand (STS) resistance exercise, for children with cerebral palsy (CP). Design A single-blind, randomized block design. Setting STS exercises were carried out at the children’s homes. Participants Twenty children (12 boys, 8 girls; age range, 5−12y) with spastic diplegia CP and classified by the Gross Motor Function Classification System as level I or II were stratified by their severity and age and randomly allocated into either the experimental or control group. Intervention Both groups received their regular physical therapy. The experimental group underwent loaded STS exercise 3 times a week for 6 weeks. Main Outcome Measures Goal dimension scores of the Gross Motor Function Measure (GMFM), gait speed, 1 repetition maximum (1-RM) of the loaded STS, isometric strength of knee extensor, and Physiological Cost Index (PCI). The outcome measures were conducted at the beginning and end of the 6-week study. Results After loaded STS exercise, the experimental group showed statistically significant differences in GMFM goal dimension scores, 1-RM STS, and PCI from the control group. The changes in gait speed and isometric strength of the knee extensor did not differ significantly between the 2 groups. Conclusions After the loaded STS exercise, children with mild spastic diplegia improved their basic motor abilities, functional muscle strength, and walking efficiency.

THE RELATION BETWEEN STANDING BALANCE AND WALKING FUNCTION IN CHILDREN WITH SPASTIC DIPLEGIC CEREBRAL PALSY

To establish and compare the relationship between standing balance and walking performance, eight children with spastic diplegic cerebral palsy (CF) and 16 non‐disabled, age‐ and sex‐matched children were studied. The results showed that the children with CP had worse static balance stability in various sensory environments and dynamic balance (rhythmic shifting ability) than the non‐disabled children. Moreover, the children with CP walked at a slower speed but at a greater physiological cost than the non‐disabled children. In the children with CP, dynamic balance significantly correlated with walking function. It is suggested that rhythmic weight‐shift training should be encouraged to improve the walking performance of children with CP.

Reliability, Sensitivity to Change, and Responsiveness of the Peabody Developmental Motor Scales–Second Edition for Children With Cerebral Palsy

Background and Purpose. The psychometric properties of the Peabody Developmental Motor Scales–Second Edition (PDMS-2), a revised motor test to assess both gross motor and fine motor composites in children with cerebral palsy (CP), are largely unknown. The purpose of this study was to examine the test-retest reliability and the responsiveness of the PDMS-2 for children with CP. Subjects. A sample of 32 children who had CP (age=27–64 months) and who received intervention participated in this study. Methods. The PDMS-2 was administered to each child 3 times (at the beginning of the study, at 1 week, and at 3 months later) by a physical therapist. The agreement between the first 2 measurements was used to examine the reliability. The change between the first and the third measurements was used to examine the responsiveness. Results. The composite scores on the PDMS-2 had good test-retest reliability (intraclass correlation coefficient=.88–1.00). The sensitivity-to-change coefficients ranged from 1.6 to 2.1, and the responsiveness coefficients ranged from 1.7 to 2.3. Discussion and Conclusion. Our results provide strong evidence that the 3 composites of the PDMS-2 had high test-retest reliability and acceptable responsiveness. The PDMS-2 can be used as an evaluative motor measure for children with CP and aged 2 to 5 years.

Prognostic factors for walking attainment in very low-birthweight preterm infants

The purpose of this study was to compare the age of walking attainment between very low-birthweight (VLBW) preterm infants and normal term infants, and to determine the variables that affect the walking attainment in VLBW infants. Ninety-six VLBW preterm infants and 82 normal term infants were prospectively followed to determine their age of walking attainment and to monitor gross motor development with sequential clinic visits at 6, 9, 12 and 18 months corrected age. Perinatal and sociodemographic data were collected through review of medical records. The VLBW infants were significantly older at attainment of walking (median 14 months) than the term infants (median 12 months) after correction for prematurity. By the age of 18 months, all term infants had attained walking ability; while 11% of VLBW infants were still unable to walk. Multivariate proportional hazards regression analysis revealed that low gestational age was significantly associated with late attainment of walking in VLBW infants. With the adjustment for gestational age, prolonged ventilation (or oxygen therapy) and severe retinopathy of prematurity were significant predictors of late walking attainment. Our findings indicate that VLBW preterm infants have an increased risk of delayed attainment of walking. Furthermore, the contribution of low gestational age to the delayed walking attainment in VLBW infants may occur via the plausible pathways of neonatal respiratory distress and severe retinopathy of prematurity.

In utero exposure to environmental lead and manganese and neurodevelopment at 2 years of age.

BACKGROUND AND OBJECTIVE Manganese, lead, arsenic and mercury are common neurotoxic metals in the environment. Nonetheless, the relationship between prenatal exposure to low doses of neurotoxic metals and neurodevelopment in children is not clear. The objective of this study was to explore the relationship between in utero exposure to environmental neurotoxic metals and neurodevelopment at 2 years of age. METHODS The population of this study came from the Taiwan Birth Panel Study. We included 230 pairs of non-smoking mothers without any occupational exposure and their singleton full-term children. The information about exposure during pregnancy was obtained using a structured questionnaire, and the manganese, lead, arsenic and mercury levels in umbilical cord blood samples were analyzed using inductively coupled plasma mass spectrometry. We used the Comprehensive Developmental Inventory for Infants and Toddlers (CDIIT) to evaluate the developmental status of each child at 2 years of age, and we examined the association of in utero exposure to environmental metals and neurodevelopment using linear regression models. RESULTS The median concentrations of manganese, lead, arsenic and mercury in the cord blood samples in this study were 47.90 µg/L (range, 17.88-106.85 µg/L), 11.41 µg/L (range 0.16-43.22 µg/L), 4.05 µg/L (range, 1.50-12.88 µg/L) and 12.17 µg/L (range, 1.53-64.87 µg/L), respectively. After adjusting for maternal age, infant gender, environmental tobacco smoke during pregnancy and after delivery, Home Observation for Measurement of the Environment Inventory results, and arsenic and mercury levels in cord blood, we found that manganese and lead levels above the 75th percentile had a significant adverse association with the overall (β=-7.03, SE=2.65, P=0.0085), cognitive (β=-8.19, SE=3.17, P=0.0105), and language quotients (β=-6.81, SE=2.73, P=0.0133) of the CDIIT. CONCLUSIONS In utero exposure to environmental manganese and lead may have an adverse association with neurodevelopment at 2 years of age, and there is an interaction effect between the manganese and lead levels in the cord blood that could aggravate the effect.

Relations of balance function and gross motor ability for children with cerebral palsy.

To investigate the relations between the balance function and gross motor ability, we recruited 15 children with cerebral palsy from 5 to 12 years in age. Balance function was tested by the Smart Balance Master System and by clinical tests. The Motor Age test was used to test gross motor ability. Analysis showed that postural stability in eyes open, eyes closed, and swaying vision conditions (visual surrounding swaying with body sway), the duration of one leg standing, and the duration of maintaining a heel-to-toe position were significantly correlated with gross motor ability. Postural stability in the eyes-closed condition was the best predicting factor and could explain 64% of the variability of gross motor ability. Whether the training of postural stability in eyes-closed condition can improve the gross motor function needs further study.

Test–retest reliability of balance tests in children with cerebral palsy

To investigate intrasession and intersession reliability of balance tests in children with or without disabilities, 50 children without disabilities (ND) and 36 children with cerebral palsy (CP) aged from 5 to 12 years were tested. Intrasession reliability of postural stability of the Smart Balance Master System and one-leg standing test were assessed in both groups and intersession reliability of the Smart Balance Master System and balance subtest of the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP) were assessed in ND children. Intersession reliability of the postural stability test in ND children, obtained using the Smart Balance Master System, was of moderate to good reliability in centre target (CT), sway vision (SV), eyes open and sway surface (EOSS), and sway vision and sway surface (SVSS; ICC 0.72 to 0.84). In children with CP, intrasession reliability was high in CT (ICC 1). One-leg standing tests in both groups also had moderate to good intersession reliability (ICC 0.56 to 0.99). Agreement of failure score of lateral rhythmic shifting (LRS) at 1 second and 2 seconds pace was 85% and 93% respectively in ND children. Within the balance subtest of BOTMP, only two items had 100% agreement. Results suggest that postural stability tests in four conditions (CT, SV, EOSS, and SVSS), LRS, one-leg standing, and walking on a line are reliable and can be used to monitor balance control in ND children. Postural stability in CT condition and one-leg standing test are reliable in children with CP. Further study is needed to establish more reliable balance tests for children with CP.

Nationwide singleton birth weight percentiles by gestational age in Taiwan, 1998-2002.

There are limited nationwide population-based data about birth weight percentiles by gestational age in Taiwan. The purpose of this study was to develop updated intrauterine growth charts that are population based and contain the information of birth weight percentiles by gestational age for singleton newborns in Taiwan. We abstracted and analyzed the birth registration database from the Ministry of the Interior in Taiwan during the period of 1998-2002 that consisted of over one million singleton births. Percentiles of birth weight for each increment of gestational week from 21 to 44 weeks were estimated using smoothed means and standard deviations. The analyses revealed that birth weight rose with advancing gestational age, with greater slopes during the third trimester and then leveled off beyond 40 weeks of gestational age. The male to female ratio ranged from 1.088 to 1.096. The mean birth weights during the period of 1998-2002 were higher than those previously reported for the period of 1945-1967; while the birth weight distribution and percentile during the period of 1998-2002 were similar to those reported for the period of 1979-1989. The 10th, 50th, and 90th percentiles of birth weigh at 40th gestational age among the male newborns were 2914, 3374, and 3890 g respectively; and for the female newborns 2816, 3250, and 3747 g. At the gestational age of 37 weeks, the 10th, 50th, and 90th percentiles of birth weigh among the male newborns were 2499, 2941, and 3433 g respectively; and for the female newborns 2391, 2832, and 3334 g. From 1998 to 2002, there was a gradual increase in the prevalence of low birth weight and preterm birth together with the percentage of infants born to foreign-born mothers. This study provides the first nationwide singleton intrauterine growth charts in Taiwan that are population-based and gender-specific. The normative data are particularly useful for the investigation of predictors and outcomes of altered fetal growth.

Optimization of walking in children

Previous work demonstrated that adults naturally adopt a walking frequency to optimize physiological cost, symmetry, and stability. Furthermore, the optimal frequency is predictable using the force-driven harmonic oscillator (FDHO) model. However, no studies have established the developmental processes of optimization in children. Thus, the purposes of this study were to examine the predictability of the preferred stride frequency (PSF) and optimization features of 3- to 12-yr-old children using the FDHO model. Forty-five children and nine adults were measured for anthropometric data to calculate the predicted frequency. They later walked at three frequencies (PSF, PSF +25%, and PSF -25%) at a constant speed on a treadmill. The results indicated that the FDHO model was accurate in predicting the preferred frequency of children (prediction error < 0.07 s). We identified three stages of learning in the development of optimization: an early manifestation of sensitivity to resonant frequency, the subsequent development of ability to modulate walking frequency, and the final establishment of an adult optimization form at age seven. Our findings suggest that walking development may be determined by the dynamic cooperation of physiological, neural, and musculoskeletal systems with respect to the environmental context.

Concurrent Validity of the Comprehensive Developmental Inventory for Infants and Toddlers with the Bayley Scales of Infant Development-II in Preterm Infants

BACKGROUND AND PURPOSE The Comprehensive Developmental Inventory for Infants and Toddlers (CDIIT) is a new developmental test designed in Taiwan and lacks concurrent validity information. This study investigated the concurrent validity of the CDIIT with the Bayley Scales of Infant Development-II (BSID-II) in preterm infants aged 6-18 and 21-40 months, respectively. METHODS We recruited 160 preterm infants (84 boys, 76 girls) with a corrected age of 6-18 months and followed them up until 21-40 months of age. One tester administered the CDIIT and BSID-II to all infants. Developmental ages (DAs) and developmental quotients (DQs) from both tests were analyzed with Pearson correlation and kappa tests. RESULTS Correlation coefficients for DAs and DQs between the 2 cognitive and motor subtests and classification agreements were high at 6-18 months (r = 0.80-0.97; kappa = 0.80, 0.85) and moderate to high at 21-40 months (r = 0.60-0.77; kappa = 0.44, 0.57). DQ classification for the CDIIT motor subtests tended to be higher than for the BSID-II motor scales at 21-40 months. CONCLUSIONS In preterm infants, concurrent validity between the motor and cognitive subtests of the CDIIT and the BSID-II was acceptable. The CDIIT can be thus used in clinics for the early identification of developmental delay in infants and toddlers.