Original articleCenter of Mass Movement and Energy Transfer During Walking in Children With Cerebral Palsy
Section snippets
Participants and Procedures
Data were collected on a convenience sample of 15 children with spastic diplegic CP and 6 age-matched controls without CP. Subjects with CP were generally community ambulators, with a mean score of 92% on the Gross Motor Function Measure (GMFM)14 and walked without aids. Subject anthropometrics are summarized in table 1. None of the subjects had undergone surgery or other significant treatments within the last 6 months. All tests were conducted in the Motion Analysis and Motor Performance
Results
The results of this study supported our hypotheses and are summarized in table 2. The vertical excursion of the normalized COM was 80% of the compass gait model’s excursion for the children with CP, but only 51% of this value in the control group. There was no difference in the lateral movement of the COM between controls and the group with CP. The children with CP had shorter strides but their preferred walking speed was not significantly slower because they had increased cadence, which
Discussion
The results of this study support our hypothesis that the gait of children with CP is less pendular than that of the controls. An ideal pendulum has PE and KE curves that are equal in amplitude, 180° out of phase, and sinewaves. We found the COM energy curves of the group with CP lacking in all 3 measures. The increased vertical excursion of the group with CP meant that there was greater variation in PE than KE during the gait cycle. The lack of symmetry of the gait, the nonsinusoidal
Conclusions
This study has shown that the use of COM parameters provides insights that can aid kinematic analysis and can be applied to the gait patterns of an individual patient to either guide or evaluate interventions. The analysis can show when energy recovery is or is not possible and estimate the improvement in mechanical work resulting from a specific change in the gait pattern. Although each patient is unique, the COM dynamics in the subjects with CP showed significant deviations from normal,
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Supported by the National Institutes of Health (grant no. 5R24HD039631) and the Pediatric Orthopaedic Society of North America.
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organization with which the author(s) is/are associated.