Motor Skills in Children and Adolescents with Autism Spectrum Disorder

Background: Children and adolescents with autism spectrum disorder (ASD) frequently display deficits in gross and fine motor skills, motor coordination, static and dynamic balance. These deficits, in turn, impair daily living tasks, such as feeding, handwriting, and buttoning, as well as motor performance in jumping, running, throwing, and sport-related activities. Subjects with ASD also present difficulties in integrating sensory input and motor output, particularly in anticipatory control and action planning.

Objectives: (1) To assess the prevalence, features and severity of motor deficits in ASD; (2) To define the clinical and patient history variables most differentiating ASD individuals with and without motor deficits; (3) To evaluate the applicability of the Movement Assessment Battery for Children-2 (Movement ABC-2) to test motor skills in ASD.

Methods: We performed a retrospective study on 100 ASD patients and a prospective study on 103 patients consecutively recruited at the Interdepartmental Program “Autism 0-90” of the “G. Martino” University Hospital in Messina (Italy). All patients were assessed using ADOS-2, ADI-R, Leiter-3, WPPSI-III, GDMS, PEP-3,VABS-II. Patients recruited for the prospective study were also assessed using the Movement ABC-2. All patients with neuroanatomical abnormalities at the MRI, history of seizures or severe EEG abnormalities, were excluded from the prospective study and data have been to this date analyzed for 55 patients (2-17 y.o., M:F=47:8).

Results:

Retrospective study - Motor deficits were detected by neurological examination in 60/100 (60%) ASD patients. Parents reported moderate-to-severe motor deficits in 57/100 (57%) for gross motor skills, 56/100 (56%) for fine-motor skills; 66/100 (66%) for visuo-motor coordination, 65/100 (65%) in bimanual coordination.

Prospective study – the Movement-ABC2 battery was completed by 26/55 (47.3%) patients. Motor deficits, either involving coordination, visuo-motor skills or balance, were recorded in 17/26 (65.4%) completers, confirming the estimates produced by our retrospective study. Non-completion of the Movement ABC-2 battery is significantly more frequent among patients with: (a) moderate or severe ASD (26/29, 89.7%, P=0.005); (b) co-morbid Intellectual Disability (27/29, 93.1%, P<0.00001); (c) deficits in receptive language with limited understanding of the instructions (22/29, 75.9%, P=0.007).

Conclusions: Moderate-to-severe deficits in motor skills have been recorded in 60-65% of ASD children and adolescents in our sample. The assessment of motor deficits in ASD is deeply influenced by autism severity, cognitive level and receptive language skills. The Movement ABC-2 battery is thus of limited use in ASD, because it can be reliably applied only to autistic subjects either high-functioning or at least endowed with sufficiently developed receptive language. These limitations spur interest in new technologies applied to ASD children in naturalistic contexts. Addressing motor deficits in a personalized treatment plan may foster improvement not only in motor performance and self-esteem, but also in social cognition and executive functions.