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Abstract
The purpose of this dissertation was to assess the vascular health of ambulatory children with spastic cerebral palsy (CP). The first study aimed to determine whether the size and hemodynamics of the popliteal artery are compromised in children with CP. The main finding was that children with CP had smaller diameter, no difference in oscillatory shear index, and higher shear rate than typically developing children. However, the difference in diameter was more evident in children with bilateral than unilateral CP, and no longer significant after adjusting for the smaller leg muscles in children with CP, indicating that the size of the popliteal artery tracks the size of the muscle. The relevance of the elevated shear rate in children with CP requires further study. The second study aimed to determine if the diameter and hemodynamics of the popliteal artery are related to physical activity and function in children with CP. The main findings were that the smaller artery diameter and higher shear rate in children with CP were associated with lower functional capacity, assessed via the 6-minute walk test. Shear rate was also inversely related to performance on the progressive lateral step-up test, a measure of functional muscle strength. However, neither diameter nor shear rate was related to physical activity. These results suggest that the limited functional capacity of children with CP may suppress popliteal artery growth. The relevance of the relationship between shear rate and functional capacity warrants further investigation. The third study aimed to determine whether blood pressure measurements are consistent across arms in children with CP. The main finding was that although high intraclass correlations between blood pressure measurements from the more- and less-affected arms indicated excellent agreement, 4 of 14 children with bilateral CP exhibited a pathologically significant inter-arm difference (>10 mmHg). Thus, assessing blood pressure in both arms may be necessary in children with bilateral CP.In conclusion, children with CP have disturbances in their vascular health that are related to their physical function, more evident in children with bilateral than unilateral CP, and require more attention from scientists and clinicians.