Postural Control Assessment in Autism Using the Pediatric Balance Scale and the Fall Screen Assessment System: Results from a Pilot Study

Background: Individuals with ASD have impairments in fine and gross motor skills, motor planning, motor coordination and praxis. A key sensorimotor control process affected by ASD is the management of upright standing. The maintenance of balance depends on the interaction of multiple sensory, motor and integrative systems (i.e. vestibular function, vision, peripheral sensation, muscle force and reaction time). A marked deficit in any one of these factors or a combination of mild impairments in multiple physiological domains may increase the risk of falling. Few studies on this topic are available in the literature and most of them have used just force platform instrumental approaches, neglecting the assessment of different balance components.

Objectives: The aims of this pilot study are: 1) to assess balance in a group of ASD subjects using the Pediatric Balance Scale (PBS), comparing the results with normative values; 2) to assess balance in the same sample, using the Fall Screen Assessment System (FSAS), comparing the results with a control group of normally developing children.

Methods: The study sample included nine ASD individuals and sixteen healthy age matched subjects. The ASD subjects were diagnosed with Autism according to the DSM V criteria, confirmed through ADOS 2 and under observation at our Institute. We employed: a) FSAS, a multi-item scale internationally validated in adult subjects, exploring sensorial and motor performances; b) PBS, a multi-item functional assessment tool exploring functional balance in the context of everyday tasks, commonly used in children and adolescents

Results:  The two groups resulted homogeneous as regards age distribution (ASD group mean age 12.2 years - 4.29 SD vs control group mean age 12.8 years - 3.8 SD). We found that five (56%) ASD subjects showed a balance deficit as detected by the PBS (scores below the normality cut-off ) and were also positive for the FSAS. Two more subjects were found at risk of falling only by FSAS. FSAS was easily applicable to children and adolescents and showed a statistically significant difference (p = <0.05) between the two groups in the following tests: visual contrast sensitivity, touch sensitivity, ankle dorsiflexion force, knee extension and flexion force, reaction time for hand, and all postural sway tests (table 1), thus evidencing an overall postural control impairment in ASD.

Conclusions:

This study confirms that ASD individuals are at major risk of falling in everyday life. This is attributable to an altered integration and elaboration of sensory and motor information. FSAS integrates the information derived from standard clinical assessment, and can be suggested as a complementary tool in the management of ASD. Moreover, by directly assessing an individual’s physiological abilities, intervention strategies can be implemented to target areas of deficit. Further studies are necessary to confirm the results of this pilot study.