Causal factors affecting gross motor function in children diagnosed with cerebral palsy

Bruce A. MacWilliams, Sarada Prasad, Amy L. Shuckra, Michael H. Schwartz

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


Background Cerebral palsy (CP) is a complex neuromuscular condition that may negatively influence gross motor function. Children diagnosed with CP often exhibit spasticity, weakness, reduced motor control, contracture, and bony malalignment. Despite many previous association studies, the causal impact of these impairments on motor function is unknown. Aim In this study, we proposed a causal model which estimated the effects of common impairments on motor function in children with spastic CP as measured by the 66-item Gross Motor Function Measure (GMFM-66). We estimated both direct and total effect sizes of all included variables using linear regression based on covariate adjustment sets implied by the minimally sufficient adjustment sets. In addition, we estimated bivariate effect sizes of all measures for comparison. Method We retrospectively evaluated 300 consecutive subjects with spastic cerebral palsy who underwent routine clinical gait analysis. Model data included standard information collected during this analysis. Results The largest causal effect sizes, as measured by standardized regression coefficients, were found for selective voluntary motor control and dynamic motor control, followed by strength, then gait deviations. In contrast, common treatment targets, such as spasticity and orthopedic deformity, had relatively small effects. Effect sizes estimated from bivariate models, which cannot appropriately adjust for other causal factors, substantially overestimated the total effect of spasticity, strength, and orthopedic deformity. Interpretation Understanding the effects of impairments on gross motor function will allow clinicians to direct treatments at those impairments with the greatest potential to influence gross motor function and provide realistic expectations of the anticipated changes.

Original languageEnglish (US)
Article numbere0270121
JournalPloS one
Issue number7 July
StatePublished - Jul 2022

Bibliographical note

Publisher Copyright:
© 2022 MacWilliams et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


  • Cerebral Palsy
  • Child
  • Disability Evaluation
  • Gait
  • Humans
  • Motor Skills
  • Muscle Spasticity
  • Retrospective Studies

PubMed: MeSH publication types

  • Journal Article


Dive into the research topics of 'Causal factors affecting gross motor function in children diagnosed with cerebral palsy'. Together they form a unique fingerprint.

Cite this