Early motor development of breech- and cephalic-presenting infants.

OBJECTIVE: This study was conducted to determine whether breech-presenting infants have a different pattern of early neuromotor development than cephalic-presenting infants--regardless of mode of delivery-thus explaining both the failure to assume cephalic version at the end of gestation and the higher rates of childhood motor impairments associated with breech presentation. METHODS: Ninety morphologically normal, term, breech-presenting singletons with birthweights greater than 2,500 g were paired with a similar cephalic-presenting infant, matched for gender and mode of delivery (n = 180; 100 delivered abdominally and 80 delivered vaginally). Data on neurological status (Neurological Assessment of the Preterm and Full-term Newborn Infant) and motor performance (Alberta Infant Motor Scale, Peabody Developmental Motor Scales, and age of walking) were collected prospectively over the first 18 months of life. This study was designed with a power of .80 to detect a "medium" effect size for motor development using the Alberta Infant Motor Scale. The data were analyzed using analysis of variance techniques. RESULTS: Breech-presenting infants had minor transient differences compared with cephalic-presenting infants. First, they had more open popliteal angles at birth (P < .001). Second, they had significantly lower motor scores at 6 weeks than the normative sample (P < .001). At 18 months, three infants were diagnosed with neurological problems, all of whom were delivered electively in the cesarean-breech group. CONCLUSION: As a group, breech-presenting infants do not have a persistent, inherently different pattern of motor development than cephalic-presenting infants. Mode of delivery did not explain the excess neuromotor impairment detected in the subgroup of breech infants.

Construction and validation of the Alberta Infant Motor Scale (AIMS).

The Alberta Infant Motor Scale (AIMS), an observational assessment scale, was constructed to measure gross motor maturation in infants from birth through independent walking. Based upon the literature, 58 items were generated and organized into four positions: prone, supine, sitting and standing. Each item describes three aspects of motor performance--weight-bearing, posture and antigravity movements. Content validation of the instrument was accomplished through a mail survey of Canadian pediatric physical therapists and consultation with an international panel of experts. Five hundred and six infants, age-stratified from birth through 18 months, participated in the reliability and validity testing of the AIMS. In addition, 20 infants who were experiencing abnormal motor development and 50 infants at risk for motor disorders were assessed and compared with the results of the full-term sample. Results to be presented include: 1) test-retest and inter-rater reliability estimates; 2) correlations between the AIMS and the Bayley and Peabody motor scores; and 3) scaling of the items along the age continuum for normal motor development.

Early developmental screening: sensitivity and specificity of chronological and adjusted scores.

The motor development of 75 preterm infants was assessed at 4 months chronological and 4 months adjusted ages using the Movement Assessment of Infants (MAI). Infants were followed until 18 months old when neurological and motor outcomes were assessed by a developmental pediatrician, and outcomes were classified as normal, suspicious, or abnormal. Sensitivity, specificity, and positive and negative predictive values were calculated at the two points in time using a variety of cutoff MAI scores. At 4 months, the practice of adjusting for prematurity resulted in the better combination of screening rates for the detection of both neurologically abnormal and neurologically abnormal/suspicious children. To obtain comparable rates, different cutoff MAI scores were used to identify the neurologically abnormal versus the neurologically abnormal/suspicious children. The optimal combination of sensitivity, specificity, positive and negative predictive values varies according to the age of assessment, the disorders being identified, and the cutoff scores employed.

Influence of medical history on assessment of at-risk infants.

The influence of knowledge of their medical history on the assessment of at-risk infants was examined. Two at-risk infants, one with a high-risk medical history and one with a low-risk history, were assessed and videotaped using the Movement Assessment of Infants. 41 physical therapists were randomly assigned to assess the videotaped examinations in four groups with different knowledge of the infants' histories (high-risk infant with actual or low-risk history; low-risk infant with actual or high-risk history). The clinical significance of the difference in total risk scores between knowledge conditions of a high-risk history and a low-risk history was greater for the low-risk infant. The higher mean total risk score for the low-risk infant assessed with a high-risk history suggests that false positive results could occur which may alter parents' perceptions and interactions with the infants and consequently influence their development.

Gross and fine motor development of preterm infants at eight and 12 months of age.

Forty-five neurologically normal preterm infants were allocated to one of two groups according to their gestational age at birth (less than 32 weeks; 32 to 36 weeks). Their gross and fine motor development was assessed at eight and 12 months chronological age and eight and 12 months adjusted age. At eight months chronological age the two groups differed significantly in both gross and fine motor development, but at eight and 12 months adjusted age and 12 months chronological age they differed significantly only in fine motor development.

Influence of gestational age on early neuromotor development in the preterm infant.

The impact of the extrauterine environment on the early neuromotor development of a cohort of 73 normally developing preterm infants was assessed prospectively by comparing the neurologic maturation from birth to term of two groups of infants born at different gestational ages (less than 32 weeks; 32 to 36 weeks). Assessments were performed at 32, 35, and 40 weeks postconceptional age. Detailed analyses revealed that the neuromotor performance at the three points in time of the two gestational age groups of preterm infants did not differ. These findings suggest that the early neuromotor development from birth to term of the normally developing preterm infant is essentially unaffected by the gestational age at birth.

Motor development at term of very low birthweight infants with bronchopulmonary dysplasia.

Forty-one preterm infants weighing less than 1500 g and less than 32 weeks' gestation at birth had a Dubowitz neurological assessment performed at 40 weeks postconceptional age. The infants were classified into three groups. Eight infants had bronchopulmonary dysplasia and severe central nervous system abnormalities, 11 infants had bronchopulmonary dysplasia alone, and 22 infants had neither bronchopulmonary dysplasia nor severe central nervous system abnormalities. The neuromotor performance of these three groups of infants was similar on all the Dubowitz assessment items at 40 weeks postconceptional age. Neuromotor development of very low birthweight infants with severe bronchopulmonary dysplasia appears to be no different from that of infants without bronchopulmonary dysplasia at 40 weeks postconceptional age utilizing the Dubowitz neurological assessment.

Impact of gestational age on preterm motor development at 4 months chronological and adjusted ages.

A cohort of 62 low-risk preterm infants was identified and followed prospectively through the first 4 months of life to assess whether motor development is determined by biological maturity or the duration of the extrauterine experience. After identification, the cohort was subdivided into two groups according to gestational age at birth: less than 32 weeks gestation (n = 23) and greater than or equal to 32 weeks gestation (n = 39). Neuromotor assessments were performed on every infant at both 4 months chronological and 4 months adjusted ages. Analyses revealed that (1) the two groups of infants differed significantly at 4 months chronological age in terms of tone, primitive reflexes and volitional movement, but not in automatic reactions, and (2) the two groups of infants differed significantly at 4 months adjusted age in terms of primitive reflexes, but not in tone, automatic reactions or volitional movement. These findings suggest that the development of volitional movement and tone appear to evolve according to biological maturity alone. In contrast, primitive reflexes and automatic reactions in the preterm infant may be influenced by both biological maturation and environmental experience.

Resolution of neurological symptoms in high-risk infants during the first two years of life.

115 high-risk infants were identified and followed prospectively over the first 24 months of life. All infants underwent neurological assessments at 12 and 24 months and developmental assessments at six and 12 months. Approximately one-quarter of the infants were considered to be 'neurologically suspicious' at 12 months of age, of whom slightly more than one-half were deemed normal by 24 months. Children who were classified as being either normal or abnormal at 12 months were highly likely to have their classification confirmed at 24 months. Abnormal and suspicious neurological outcomes at 12 and 24 months were inversely correlated with birthweight and were not affected by the infants being given early physical therapy. Children who were suspicious at 12 months and who either remained suspicious or became abnormal at 24 months had lower personal-social quotients at six and 12 months and lower hearing-speech quotients at 12 months than the suspicious children who became normal.

Early physical therapy effects on the high-risk infant: a randomized controlled trial.

A prospective, randomized, controlled trial was conducted to assess the effects of early physical therapy on infants at risk for neurologic sequelae and to evaluate the impact of such early treatment on the prevention or minimization of future handicaps. A cohort of 134 infants who had received care in two Montreal inborn neonatal intensive care units was identified prospectively. Infants were stratified according to prognosis and birth weight and were randomly assigned to either an experimental or control group. Babies assigned to the experimental group received early physical therapy, whereas those allocated to the control group received conventional follow-up care. Outcome measures were administered by independent evaluators at 12 months and included measures of neurologic status, motor and overall development, and physical growth. No statistically significant differences on any of the measured outcomes at 12 months were found between the experimental and control groups. Infants weighing less than 750 g at birth, regardless of group assignment, consistently demonstrated significant delays in their growth and development when compared with their heavier peers. The early physical therapy program investigated in this study was not efficacious in altering the pattern of motor development in those high-risk infants participating in the trial.

Developmental profile of Down's syndrome infants receiving early intervention.

Thirty-two infants with Down's syndrome, who were enrolled in an early intervention programme were followed during the first 2 years of life. Progress in five developmental domains was monitored prospectively by evaluating the children at 6, 12, 18 and 24 months. The largest degree of retardation was consistently exhibited in the hearing and speech subscale. The locomotor subscale experienced the most severe decline over the 24 months and was the second most retarded domain at 2 years of age. The remaining three subscales, personal-social, hand-eye and performance, demonstrated less severe declines over time as well as actual increases in developmental quotients at specified points in time. The overall performance of female infants at 18 months was significantly better than that of male infants (P = 0.05). The degree of retardation of Down's syndrome infants receiving early intervention services differs according to chronological age, developmental domain and sex.

Cervical spine disorders. A comparison of three types of traction.

A randomized clinical trial was conducted to evaluate the efficacy of three commonly employed forms of traction in the treatment of cervical spine disorders. One hundred consenting men and women with disorders of the cervical spine were randomly assigned to one of four treatment groups, static traction, intermittent traction, manual traction, or no traction. All patients, regardless of group assignment, were seen twice weekly. The four groups were shown to be similar with regard to age, sex, diagnosis, chronicity, and prescores on the seven outcome measures. Although the entire cohort of neck patients, regardless of group assignment, improved significantly on all the outcome variables over the 6-week period, patients receiving intermittent traction performed significantly better than those assigned to the no traction group in terms of pain (P = 0.03), forward flexion (P = 0.01), right rotation (P = 0.004) and left rotation (P = 0.05).

Effect of gestational age on neurological functioning of the very low-birthweight infant at 40 weeks.

A cohort of 97 very low-birthweight infants who had had prolonged care in two neonatal units was identified prospectively and subdivided into three groups according to gestational age at birth (23 to 27, 28 to 31 and 32 to 36 weeks). The neurological status of the three groups was compared at 40 weeks gestational age. The effects of various medical complications also were analyzed by comparing the neurological performances at term of nine 'at-risk' fullterm infants with 'complicated' preterm infants, and 15 'normal' fullterm infants with 'healthy' preterm infants. After controlling for medical complications, no significant difference in neurological scores was found between the three preterm groups, nor between the preterm groups and the 'at-risk' fullterm group. However, 'healthy' preterm infants had significantly lower scores than fullterm 'normal' infants. Item analyses also showed significant differences between the three preterm groups: those with gestations between 23 and 27 weeks were more likely to exhibit tremors than the other two groups; and those with gestations of 32 to 36 weeks were more likely to have opisthotonic postures, overshooting movements, hypertonus and exaggerated responses. While preterm infants in general do not differ in neurological functioning from 'at-risk' fullterm infants, they do differ significantly from 'normal' fullterm babies. Similarly, some groups of infants born too soon exhibit specific neurological features which differentiate them from their preterm counterparts.

Cerebral Palsy I.

Physical and occupational therapists have long been associated with the care and treatment of children with cerebral palsy. This review paper examines this association in light of current prevalence data and clinical research findings. A variety of epidemiological issues, such as the impact of neonatal intensive care and the risk of preterm birth are considered. Recent evidence suggests that cerebral palsy as a neuromotor disorder is not appearing. Implications of this finding for physical and occupational therapists are discussed.

Cerebral Palsy II.

Information currently available on the etiology of cerebral palsy is reviewed. Research findings from three sources, animal data, fetal movement analyses, and clinical studies, suggest that prenatal factors may play a more important role in the etiology of cerebral palsy than previously thought. Implications for physical and occupational therapists, in terms of new roles therapists may assume in the future, are discussed. New challenges may be found in standardizing measures of motor development, analyzing fetal motor patterns and contributing to the primary prevention of motor dysfunction.

Evaluation of a sensory-motor education programme for 'parents-to-be'.

A controlled clinical trial was conducted to evaluate a sensory-motor education programme presented to expectant parents in prenatal classes. Short information sessions on sensory-motor development were provided to experimental parents by an occupational therapist. Statistically significant differences between experimental and control groups were noted in the home environments at 3 months of age, with the experimental families exhibiting more favourable environments. No statistically significant differences in development at 8 months of age between the two groups were observed.