Profiles of muscle asymmetry in children with intellectual disabilities and their neurotypical peers within the tensegrity framework

BACKGROUND: Various sources report that individuals with intellectual disabilities exhibit specific characteristics of motor development, manifested by reduced physical capacities, atypical development of movement patterns, and impaired locomotor functions. Viewing the body as an integrated whole, this study aimed to identify profiles of motor asymmetries from a tensegrity model perspective that are characteristic of individuals with intellectual disabilities and those with neurotypical development. This objective is relevant not only for physical parameters, but also for understanding how mental and intellectual domains influence the mechanisms of motor act execution.

AIM: To determine muscle asymmetry profiles in children with intellectual disabilities and their neurotypical peers from the tensegrity model perspective.

METHODS: The study was conducted in special and general education institutions in Yekaterinburg and involved 80 children aged 13 years: 40 with mild intellectual disabilities and 40 with neurotypical development. The Humac Norm biomechanical testing and rehabilitation system (CSMi Medical Solutions, USA) was used for assessment. The following muscle groups were examined: hip flexors and extensors, hip abductors and adductors, ankle flexors and extensors, shoulder flexors and extensors, and shoulder abductors and adductors. Muscle strength and endurance were assessed, and functional motor asymmetries were identified by comparing test results between limbs. Statistical analysis was performed using SPSS. For comparative analysis of the two groups, the Kruskal–Wallis non-parametric one-way ANOVA was used. Quantitative data were described using the median and the 1st and 3rd quartiles.

RESULTS: Comprehensive analysis in the group with intellectual disabilities revealed side asymmetry in hip flexors, hip abductors, shoulder adductors, and shoulder flexors and extensors. In individuals with neurotypical development, all side-deficit values were within the acceptable range (up to 20%) with no side asymmetry. The differences between groups were statistically significant.

CONCLUSIONS: In children aged 13 years with intellectual disabilities, an asynchronous profile was identified in 62.5% of cases, a lateral profile in 22.5%, and a neurotypical profile in 15%. In neurotypical children, these profile types were observed in 12.5%, 15%, and 72.5% of cases, respectively. Intellectual impairment was associated with reduced muscle performance, which collectively forms the basis for targeted corrective interventions specific to physical development.