Toddle temporal-spatial deviation index: Assessment of pediatric gait

Abstract

This research aims to develop a gait index for use in the pediatric clinic as well as research, that quantifies gait deviation in 18-22 month-old children: the Toddle Temporal-spatial Deviation Index (Toddle TDI). 81 preterm children (≤32 weeks) with very-low-birth-weights (≤1500g) and 42 full-term TD children aged 18-22 months, adjusted for prematurity, walked on a pressure-sensitive mat. Preterm children were administered the Bayley Scales of Infant Development-3rd Edition (BSID-III). Principle component analysis of TD children's temporal-spatial gait parameters quantified raw gait deviation from typical, normalized to an average(standard deviation) Toddle TDI score of 100(10), and calculated for all participants. The Toddle TDI was significantly lower for preterm versus TD children (86 vs. 100, p=0.003), and lower in preterm children with <85 vs. ≥85 BSID-III motor composite scores (66 vs. 89, p=0.004). The Toddle TDI, which by design plateaus at typical average (BSID-III gross motor 8-12), correlated with BSID-III gross motor (r=0.60, p<0.001) and not fine motor (r=0.08, p=0.65) in preterm children with gross motor scores ≤8, suggesting sensitivity to gross motor development. The Toddle TDI demonstrated sensitivity and specificity to gross motor function in very-low-birth-weight preterm children aged 18-22 months, and has been potential as an easily-administered, revealing clinical gait metric.

The Pediatric Temporal‐spatial Deviation Index: quantifying gait impairment for children with cerebral palsy

“…This work builds on our previous work, the Toddle TDI, a TDI for toddlers aged 18 to 22 months . As expected, the parameters included in each index varied.…”

“…The Pediatric TDI provides a quantitative assessment of gait, for use as a screening tool in pediatric clinics, and to assess clinical treatment outcome. The Pediatric TDI builds upon the Toddle TDI to characterize gait in children aged 7 to 11 years.…”

“…For each child, three to four ‘best effort’ trials with a total of at least 12 footfalls were analyzed, selected based on walk length, straightness, and pace consistency. These selection criteria were based on the Toddle TDI …”

“…We collected 26 candidate features for use in the construction of the Pediatric TDI based on expected relevance to motor function as described in previous studies and shown in Figure . A near‐zero‐variance check using frequency ratio and proportion of unique values was implemented to screen for features that could make the model numerically unstable; no variables were flagged.…”

“…PCA was performed to decouple the highly interrelated gait parameters into a set of independent components as illustrated in Figure 1, similar to the Toddle TDI and GDI. 11,13 Before PCA, undersampling was used to address the imbalanced data set containing five times more typically developing participants than participants with CP. A balanced data set places greater emphasis on the rare phenotypes and captures the differences between the common (typically developing) and rare (CP) phenotypes.…”