Postural control in children with and without neurofibromatosis type 1

Clinical evaluation of muscle functions in neurofibromatosis type 1

AIM

Muscle weakness, fatigue and speech problems can occur in neurofibromatosis type 1 (NF1). The pathogenesis of these symptoms is unclear, likely multifactorial. We examined motor function in limb and speech muscles in NF1 patients.

METHODS

We evaluated NF1 and control groups aged 4-18 years for muscle strength, tone and mobility using standard manual testing, joint motion and Beighton score measurements. Speech and language functions were assessed by speech articulation and resonance. As a marker of muscle tissue turnover, we determined collagen degradation products in urine before and after submaximal exercise.

RESULTS

NF1 patients had reduced strength in proximal limb muscles compared to control subjects. Speech articulation problems and hypernasality were more common in NF1 (47% and 38%, respectively). Collagen products excreted in urine correlated with gluteal and biceps muscle strength.

CONCLUSION

Muscle dysfunction can be detected in some children with NF1 and may explain certain clinical features including fatigue, speech and articulation problems. If confirmed by further research, these findings may be relevant to the management of this condition.

Age and sex differences in human balance performance from 6-18 years of age: A systematic review and meta-analysis

Background

The process of growing leads to inter-individual differences in the timing of growth, maturational, and developmental processes during childhood and adolescence, also affecting balance performance in youth. However, differences in balance performance by age and sex in youth have not been systematically investigated yet.

Objective

The objective of the present study was to characterize and quantify age- and sex-related differences in balance performance in healthy youth.

Methods

A computerized systematic literature search was performed in the electronic databases PubMed, Web of Science, and SPORTDiscus. To be applicable for analysis, studies had to report at least one measure of static steady-state, dynamic steady-state, proactive or reactive balance in healthy children (6–12 years) and/or adolescents (13–18 years). Coding of the studies was done according to the following criteria: age, sex, and balance outcome. Study quality was assessed using the Appraisal tool for Cross-Sectional Studies. Weighted standardized mean differences were calculated and classified according to their magnitude.

Results

Twenty-one studies examined age-related differences in balance performance. A large effect for measures of static steady-state balance (SMD_ba = 1.20) and small effects for proxies of dynamic steady-state (SMD_ba = 0.26) and proactive balance (SMD_ba = 0.28) were found; all in favor of adolescents. Twenty-five studies investigated sex-related differences in balance performance. A small-sized effect was observed for static steady-state balance (SMD_bs = 0.33) in favor of girls and for dynamic steady-state (SMD_bs -0.02) and proactive balance (SMD_bs = -0.15) in favor of boys. Due to a lack of studies, no analysis for measures of reactive balance was performed.

Conclusions

Our systematic review and meta-analysis revealed better balance performances in adolescents compared to children, irrespective of the measure considered. Sex-related differences were inconsistent. These findings may have implications for example in terms of trainability of balance in youth that should be investigated in future studies.

The postural stability of children with foetal alcohol spectrum disorders during one-leg stance: A feasibility study

Background

Postural control may be impaired in children with foetal alcohol spectrum disorders (FASD). The study assessed the protocol feasibility in terms of (1) recruiting children with FASD in a rural, small town; (2) using the measurement instruments in a real-life setting; (3) the one-leg standing (OLS) task and (4) presenting preliminary results on postural stability of children with and without FASD.

Methods

Nine-year-old children diagnosed with and without FASD were invited to participate. Twenty-eight children performed OLS. Feasibility outcomes included recruitment, measurement instrument use and task instruction. Postural stability outcomes included standing duration, centre of pressure (COP) and body segment acceleration.

Results

Participants recruitment was feasible in terms of the (1) ability to sample a reasonable participant number in a rural town setting and the capacity to increase the sample size if more schools are included in the sampling frame and (2) use of assent and consent forms that were appropriate for this population. The measurement instruments were user-friendly, cost-effective and time-efficient. Instructions for the task require amendment to address foot placement of the non-weight–bearing leg. There was a significant difference between cases and controls on mean COP velocity (p = 0.001) and the pelvis segment acceleration in the mediolateral direction (p = 0.01) and the anteroposterior direction (p = 0.027). The control children took longer to achieve postural control. The girls demonstrated a significant difference for the COP anteroposterior displacement (p = 0.008) and velocity (p = 0.049).

Conclusions

The recruitment of children with and without FASD in a rural, small town and the administration of measurement instruments in a real-life, school-based setting was feasible. However, the verbal instructions for the task require revision. The male control group took longer to achieve postural control because the task was performed differently between the two groups. However, the case girls were slower to achieve postural control than control girls though performing the task similarly.

Motor impairment in children with Neurofibromatosis type 1: Effect of the comorbidity with language disorders

BACKGROUND

There is a body of evidence demonstrating comorbidity of motor and cognitive deficit in «idiopathic» developmental disorders. These associations are also found in developmental disorders secondary to monogenic disorders as in Neurofibromatosis type 1 for which the principal complication during childhood is learning disabilities. The comparison of motor impairment between developmental disorders either idiopathic or secondary as in NF1 could help us to better understand the cause of the combined language/motor deficit in these populations.

AIM

The aim of this current study was to investigate motor impairment in children with NF1 for which oral language had been specified and then to compare the motors skills of the NF1 group to motor performance of children with Specific Language Disorder (SLD).

METHOD

Two groups of 49 children between 5 and 12years old were included and compared, the NF1 group and the SLD (Specific Language Disorder) group. Each child completed evaluation involving cognitive, language and motor assessment.

RESULTS

In NF1 group, motor impairment was more frequent and more severe and concerned specifically balance rather than manual dexterity or ball skills, compared to a group of children with SLD. This motor impairment was independent of language status in the NF1 group.

CONCLUSIONS

These results as well as other studies on the same topic could suggest that in NF1 children, fine motor skills impairment would be dependent on the existence of comorbidity with language disorders. Also, that gross motor skills impairment, and more precisely the balance deficit would be characteristic of NF1. This issue encourages studies of procedural learning that can involve the fronto-striatal or the fronto-cerebellar loops according to the type of motor tasks and the stage of learning.