Outcomes of infants with idiopathic hypotonia

Identifying and Evaluating Young Children with Developmental Central Hypotonia: An Overview of Systematic Reviews and Tools

Children with developmental central hypotonia have reduced muscle tone secondary to non-progressive damage to the brain or brainstem. Children may have transient delays, mild or global functional impairments, and the lack of a clear understanding of this diagnosis makes evaluating appropriate interventions challenging. This overview aimed to systematically describe the best available evidence for tools to identify and evaluate children with developmental central hypotonia aged 2 months to 6 years. A systematic review of systematic reviews or syntheses was conducted with electronic searches in PubMed, Medline, CINAHL, Scopus, Cochrane Database of Systematic Reviews, Google Scholar, and PEDro and supplemented with hand-searching. Methodological quality and risk-of-bias were evaluated, and included reviews and tools were compared and contrasted. Three systematic reviews, an evidence-based clinical assessment algorithm, three measurement protocols, and two additional measurement tools were identified. For children aged 2 months to 2 years, the Hammersmith Infant Neurological Examination has the strongest measurement properties and contains a subset of items that may be useful for quantifying the severity of hypotonia. For children aged 2-6 years, a clinical algorithm and individual tools provide guidance. Further research is required to develop and validate all evaluative tools for children with developmental central hypotonia.

Developmental Coordination Disorder before the Age of Three: A Longitudinal Retrospective Study in a Belgian Center for Developmental Disabilities

This study aimed to explore the association between developmental coordination disorder (DCD) diagnosed after the age of three and both a standardized motor test—the Alberta Infant Motor Scale (AIMS)—and non-standardized observation of movement quality carried out before the age of three. Children at risk or with developmental concerns were studied retrospectively. Children were excluded in case of a diagnosis, excluding DCD, e.g., cerebral palsy, or IQ < 70. Of the 503 included children, 246 were diagnosed with (at-risk) DCD. Multivariate binary logistic regression revealed a significant association between DCD diagnosis after the age of three and male gender and with different aspects of poor movement quality in different age groups before the age three. Univariate analyses revealed an association between DCD diagnosis and the number of poor movement-quality descriptions at 0−6 months, 6−12 months, and 18 months−3 years but not with the AIMS scores. The MABC-2 scores after the age of three were significantly correlated with the number of poor movement-quality descriptions in age groups 0−6 months and 18 months−3 years and with the AIMS scores in age groups 6−12 months and 12−18 months. The results suggest that DCD can be associated with poor movement quality before the age of three.

Neuropsychology consultation to identify learning disorders in children and adolescents: a proposal based on lessons learned during the COVID-19 pandemic

Learning disorders are common neurodevelopmental conditions, occurring both idiopathically and in the context of other medical conditions. They are frequently comorbid with other neurodevelopmental and psychiatric conditions. Delayed identification and treatment have been associated with significant negative psychosocial consequences. The need for pediatric neuropsychologists to efficiently screen for learning disorders is likely to increase in the months and years following the COVID-19 pandemic, which has severely disrupted access to educational services, especially for children who also face racial and economic disparities. In this paper, we describe a consultation model that can be used to screen for learning disorders and can be completed using both in-person and telemedicine visits. Implementation may result in earlier intervention for struggling children, increase access to neuropsychological services without increasing wait times for comprehensive evaluations, and provide opportunities for collaborations with other health professionals (e.g., pediatricians, therapists, psychiatrists, and neurologists).

Improvement in Overground Walking After Treadmill-Based Gait Training in a Child With Agenesis of the Corpus Callosum

BACKGROUND

Agenesis of the corpus callosum (ACC) is a rare congenital brain defect that produces a wide variety of cognitive and motor impairments. Literature regarding the response of pediatric populations with ACC to physical rehabilitation is scarce. Treadmill-based gait training (TT) has been shown to improve walking ability in some pediatric populations but has not been investigated in children with ACC.

OBJECTIVE

The purpose of this study was to investigate the effect of a novel treadmill intervention paradigm on the gait parameters of a child with ACC.

DESIGN

A single-participant design with 2 phases was used.

METHODS

The settings were the participant's home and the laboratory. The participant was a 13-year-old girl who had ACC and cortical visual impairment and who ambulated independently using a reverse walker for household and short community distances. A home-based TT intervention (2 phases of 3 months of training over 6 months) was implemented, and a laboratory-based gait analysis was conducted at 4 time points: baseline, after each of the 2 training phases, and 3 months after the cessation of training. The intervention consisted of weekly bouts of TT. Phase I incorporated forward, backward, and incline walking for 15 minutes each; in phase II, this protocol was continued, but short-burst interval training for 10 minutes was added. Data collected at each laboratory visit included spatiotemporal parameters and kinematics (joint angles) during overground and treadmill walking.

RESULTS

After both phases of training, increased step length, decreased step width, and foot progression angle and decreased variability of most spatiotemporal parameters were observed for the participant. Further, after phase II, increased peak extension at the hip, knee, and ankle, decreased crouched gait, and improved minimum foot clearance during overground walking were observed. Most gait improvements were retained for 3 months after the cessation of the intervention.

LIMITATIONS

The small sample size of this study and wide variety of presentations within individuals with ACC limit the generalizability of our findings.

CONCLUSIONS

TT may be a safe and effective treatment paradigm for children with ACC. Future research should investigate the effect of intervention dosage on gait improvements and generalization in individuals with ACC.

Early infant neuromotor assessment is associated with language and nonverbal cognitive function in toddlers: the Generation R Study

OBJECTIVE

Numerous studies in high-risk populations established that variations in infant neuromotor development predict poor cognitive function. It is unclear whether this association is found in the general population. Moreover, previous population-based studies mostly focused on motor milestone achievement.

METHODS

This study was embedded in the Generation R Study, a population-based cohort in Rotterdam, the Netherlands. Neuromotor development was assessed with an adapted version of Touwen's Neurodevelopmental Examination when infants (1205 males, 1278 females) were on average 12 weeks old (standard deviation 1, range, 9-15 weeks). To measure language function at age 1.5 years, the MacArthur Short Form Vocabulary Checklist was used. At 2.5 years, mothers completed the Language Development Survey and the Parent Report of Children's Abilities measuring language and nonverbal cognitive functioning, respectively.

RESULTS

After adjustment for confounders, less optimal neuromotor development, that is, more low tone symptoms, was associated with a delay in receptive language at 1.5 years (odds ratio [OR], 1.18; 95% confidence interval [CI], 1.05-1.34) and in expressive language at multiple time points (OR, 1.11; 95% CI, 1.02-1.21). Higher scores on overall neuromotor development, indicating a less optimal neuromotor development, was associated with an increased risk of a delay in nonverbal cognitive function at 2.5 years (OR, 1.19; 95% CI, 1.05-1.35).

CONCLUSIONS

The results of this study suggest that infants with more low tone symptoms, indicating minor deviances from normal neuromotor development, are somewhat more vulnerable to language delays than those infants who do not have these symptoms.

Clinical decision making in hypotonia and gross motor delay: a case report of type 1 spinal muscular atrophy in an infant

BACKGROUND AND PURPOSE

Children often are referred for physical therapy with the diagnosis of hypotonia when the definitive cause of hypotonia is unknown. The purpose of this case report is to describe the clinical decision-making process using the Hypothesis-Oriented Algorithm for Clinicians II (HOAC II) for an infant with hypotonia and gross motor delay.

CASE DESCRIPTION

The patient was a 5-month-old infant who had been evaluated by a neurologist and then referred for physical therapy by his pediatrician. Physical therapist evaluation results and clinical observations of marked hypotonia, significant gross motor delay, tongue fasciculations, feeding difficulties, and respiratory abnormalities prompted necessary referral to specialists. Recognition of developmental, neurologic, and respiratory abnormalities facilitated clinical decision making for determining the appropriate physical therapy plan of care.

OUTCOMES

During the brief episode of physical therapy care, the patient was referred to a feeding specialist and diagnosed with pharyngeal-phase dysphasia and mild aspiration. Continued global weakness, signs and symptoms of type 1 spinal muscular atrophy (SMA), and concerns about increased work of breathing and respiratory compromise were discussed with the referring physician. After inconclusive laboratory testing for metabolic etiologies of hypotonia, a genetics consult was recommended and confirmed the diagnosis of type 1 SMA at 9 months of age.

DISCUSSION

Physical therapists use clinical decision making to determine whether to treat patients or to refer them to other medical professionals. Accurate and timely referral to appropriate specialists may assist families in obtaining a diagnosis for their child and guide necessary interventions. In the case of type 1 SMA, early diagnosis may affect outcomes and survival rate in this pediatric population.

Hypotonia, jaundice, and Chiari malformations: relationships to executive functions

This article postulates that movement and action control are the underpinning of executive functioning. We selectively examine brain regions that have traditionally been almost exclusively understood as critical to the control and expression of movement-namely, the basal ganglia and the cerebellum. We first describe the relationship between movement and cognition. This is followed by a review of common developmental disorders that are known to exhibit abnormal executive functions and movement anomalies. Against that background, we examine hypotonia, neonatal jaundice, and Chiari I malformation, and we demonstrate why these are "at-risk" factors for neurodevelopmental disorders that can feature both motor control and executive function abnormalities. Our goal is to prepare the clinical neuropsychologist for gathering information about these features of a child's birth and developmental histories, while using this as a framework for interpreting test results and applying test data in a useful, practical way to guide descriptive diagnosis and treatment.

Congenital hypotonia: clinical and developmental assessment

Identifying the underlying cause of congenital hypotonia remains difficult, despite advances in diagnostic laboratory and imaging techniques. Clinical evaluation strategies and standardized developmental tests can assist in differentiating hypotonia resulting from primary involvement of the upper motoneuron (central hypotonia) versus that involving the lower motoneuron and motor unit (peripheral hypotonia). This is especially important in infants with idiopathic hypotonia. This review outlines and describes the components of the clinical assessment: detailed infant and family history, clinical techniques and characteristics for differentiating hypotonia of central versus peripheral origin, and clinical evaluation (muscle tone, primitive reflexes, deep tendon reflexes, etc). Recent research that has contributed to the differential diagnosis of congenital hypotonia is reviewed and directions for future research are provided. Ideally, the assessment of infants with congenital hypotonia is best accomplished by an interdisciplinary team of developmental specialists including pediatricians, medical geneticists, child neurologists, and physical or occupational therapists.