Mazzarella J1, Schram M2, Chaudhari A2, Heathcock J1
1Ohio State University, Physical Therapy, Columbus, United States, 2Ohio State University, Columbus, United States
Background: Neonatal stroke (NS) occurs around the time of birth, and is the leading cause of hemiplegic cerebral palsy (CP). Motor asymmetries become clinically apparent in this population at 6-9 months old. Early identification of motor asymmetries in this population is crucial for initiating targeted early intervention services. Studies on infant reach development have utilized kinematic measurement for detailed movement analysis. The maturation of pre-reaching and reaching movements in infants with typical development (TD) is well-defined in the literature, however it has not been documented in the NS population.
Purpose: The purpose of this study was to determine if kinematic measurement can be used to detect early motor asymmetries in infants with NS. To do this, we measured the spontaneous upper extremity (UE) movements of infants with NS and with TD at 8 weeks old, using kinematic variables that measured both spatial and temporal properties of the movement. We hypothesized that the movement of infants with NS would be less mature on their involved side compared to their uninvolved side, and compared to infants with TD, indicated by slower and less straight movements.
Methods: We measured 22 8-week-old, full-term infants, 11 with TD and 11 with NS, confirmed with MRI by a radiologist. The infants were secured in a custom chair that allowed free arm movement, angled 30° from vertical. Reflective markers were placed on both hands, and movement was recorded at 120 Hz for 3, 30-second trials, using a 10-camera VICON system. In each trial, a toy was presented to the infants at midline shoulder height to stimulate UE movements. Dependent variables included straightness ratio (SR) (path length/movement length), movement speed, and number of velocity peaks; all reliable measures of UE coordination in pediatric populations.
Results: Independent samples Kruskal-Wallis tests revealed no asymmetries between the left (L) and right (R) UE for infants with TD (p>.05). No asymmetries were present between the involved (I) and uninvolved (U) UE for infants with NS (p>.05): SR χ2(1)=.056, mean ranks: U= 32.94 I=34.06; movement speed χ2(1)=.364, mean ranks: U=34.39 I=31.56; number of velocity peaks χ2(1)=.969, mean ranks: NS=35.34 TD=30.73. Additionally, there were no group mean differences (p>.05): SR χ2(1)=.752, mean ranks: NS=37.23 TD=41.77; movement speed χ2(1)=.419, mean ranks: NS=40.32 TD=36.93; number of velocity peaks χ2(1)=.519, mean ranks: NS=37.53 TD=41.30.
Conclusion(s): Kinematic measurement did not detect asymmetries in spontaneous UE movements in 8-week-old infants with NS, nor did it reveal any difference between infants with NS and infants with TD, with regards to the variables we measured. Moving forward, we will compare multiple measurements over time, to determine at what age kinematic measurement does detect movement asymmetries.
Implications: This population will benefit from close monitoring throughout early development, in order to provide early targeted intervention for the infants who do develop motor asymmetries. Continued research is needed to determine the efficacy of kinematic movement analysis for identification of early motor asymmetries in infants with NS.
Keywords: Neonatal Stroke, Kinematics, Movement Analysis
Funding acknowledgements: The Foundation for Physical Therapy
Purpose: The purpose of this study was to determine if kinematic measurement can be used to detect early motor asymmetries in infants with NS. To do this, we measured the spontaneous upper extremity (UE) movements of infants with NS and with TD at 8 weeks old, using kinematic variables that measured both spatial and temporal properties of the movement. We hypothesized that the movement of infants with NS would be less mature on their involved side compared to their uninvolved side, and compared to infants with TD, indicated by slower and less straight movements.
Methods: We measured 22 8-week-old, full-term infants, 11 with TD and 11 with NS, confirmed with MRI by a radiologist. The infants were secured in a custom chair that allowed free arm movement, angled 30° from vertical. Reflective markers were placed on both hands, and movement was recorded at 120 Hz for 3, 30-second trials, using a 10-camera VICON system. In each trial, a toy was presented to the infants at midline shoulder height to stimulate UE movements. Dependent variables included straightness ratio (SR) (path length/movement length), movement speed, and number of velocity peaks; all reliable measures of UE coordination in pediatric populations.
Results: Independent samples Kruskal-Wallis tests revealed no asymmetries between the left (L) and right (R) UE for infants with TD (p>.05). No asymmetries were present between the involved (I) and uninvolved (U) UE for infants with NS (p>.05): SR χ2(1)=.056, mean ranks: U= 32.94 I=34.06; movement speed χ2(1)=.364, mean ranks: U=34.39 I=31.56; number of velocity peaks χ2(1)=.969, mean ranks: NS=35.34 TD=30.73. Additionally, there were no group mean differences (p>.05): SR χ2(1)=.752, mean ranks: NS=37.23 TD=41.77; movement speed χ2(1)=.419, mean ranks: NS=40.32 TD=36.93; number of velocity peaks χ2(1)=.519, mean ranks: NS=37.53 TD=41.30.
Conclusion(s): Kinematic measurement did not detect asymmetries in spontaneous UE movements in 8-week-old infants with NS, nor did it reveal any difference between infants with NS and infants with TD, with regards to the variables we measured. Moving forward, we will compare multiple measurements over time, to determine at what age kinematic measurement does detect movement asymmetries.
Implications: This population will benefit from close monitoring throughout early development, in order to provide early targeted intervention for the infants who do develop motor asymmetries. Continued research is needed to determine the efficacy of kinematic movement analysis for identification of early motor asymmetries in infants with NS.
Keywords: Neonatal Stroke, Kinematics, Movement Analysis
Funding acknowledgements: The Foundation for Physical Therapy
Topic: Neurology: stroke; Paediatrics; Human movement analysis
Ethics approval required: Yes
Institution: Nationwide Children's Hospital
Ethics committee: Institutional Review Board
Ethics number: IRB08-00292
All authors, affiliations and abstracts have been published as submitted.
