31848
Gait Analysis in Children and Young Adults with Autism Spectrum Disorders Using Instrumented Insoles
The diagnosis of autism spectrum disorder (ASD), is based on two behavioral criteria: (1) social and communication impairments; and (2) restricted interests and/or repetitive behaviors. Motor abnormalities, not considered “core” diagnostic criteria, are nonetheless prominent and lifelong in idiopathic or genetic-based ASD. Common clinical tools often lack the sensitivity to capture subtle differences to further define the motor profile across the lifetime. Consequently, the motor phenotype of ASD remains ill-defined. Moreover, due to lack of accuracy in measurement, motor behaviors are not considered valid outcome measures, despite their potential response to behavioral or pharmacological treatment. Among motor behaviors, gait in older children or adults with ASD have been analyzed using cumbersome equipment, and report mixed results in cadence, stride length and base of support. The advent of wearable technologies encourages the use of quantitative gait assessments that are independent of potential clinical assessment limitation.
Objectives:
This project addresses the challenge of accurately measuring gait in children and adults with HNRNPH2-variant who present ASD, anxiety, developmental delays and motor impairments. We used a novel unobtrusive wearable technology (instrumented insoles) developed by our team, to validate our gait methodology against usual command-based motor assessments, which often introduce bias in assessments due to the inherent behavioral constraints of ASD. Herein we show, in a naturalistic environment, the significant value of this technology to assess spatial and temporal features of gait that are not easily identifiable by an observer. The identification of precise gait abnormalities will shed light on underlying motor pathway dysfunctions such as the cerebellum involved in motor control and walking behavior
Methods:
Six patients with HNRNPH2/ASD and two typically developing controls, aged between 5 and 37 years were evaluated. Participants with ASD received complete neurological, neuropsychological, and clinical motor assessments using standardized instruments as well as ASD diagnosis using the gold standard battery. Wearing shoes equipped with comfortable instrumented insoles, participants performed gait (preferred and fast pace, running) and balance tasks (standing on one leg). The gold standard electronic walkway (Zeno mat) was used for comparison to the wearable device in quantifying spatial (stride length, velocity) and temporal (stride time, swing time) gait parameters as participants completed 4 full laps along a 16-meter long straight-line path. All sessions were videotaped.
Results:
All 6 subjects tolerated well the instrumented insoles and, performed safely the walking tasks. We found very good level of agreement between the wearable system and the reference system. In relative terms, mean-absolute-errors (MAE) in stride time, length and velocity were ≤4.2% and ≤1.6% for ASD and controls, respectively. For swing time, the percentage MAE was 5.3% for ASD and 3.0% for controls
Conclusions:
The study confirms, for the first time, the validity and ease of use of our instrumented insoles to accurately assess spatial and temporal gait parameters in individuals with ASD with low complain. These results provide strong support for further gait studies in order to interrogate motor pathways and to characterize the motor trajectory of children and adults with idiopathic or genetic-based ASD.