The effect of a low-load plyometric intervention on running kinematics in youth with cerebral palsy: A randomised controlled trial.

Background: For children and adolescents with cerebral palsy (CP) who are independently ambulant (Gross Motor Function Classification System (GMFCS) I or II), running is a fundamental movement skill that enables them to play and engage in school and community activities. A running intervention which resulted in good running goal attainment should logically have improved running kinematics, however, this has not yet been established.

Research Question: Does a low-load plyometric running intervention improve joint kinematics during running in children with CP?

Methods: Three-dimensional gait analysis was undertaken before and after a 12-week intervention. The Gait Profile Score (GPS) was calculated, and linear mixed models were developed.

Results: 36 children with cerebral palsy (control group: male=10, female=8, GMFCS I=12, GMFCS II=6, mean age=12.7 years; intervention group: male=13, female=5, GMFCS I=12, GMFCS II=6, mean age=12.7 years) were included in this study. No significant between-group differences in GPS were found at follow-up. The GPS increased (i.e. running kinematics became more atypical) as speed increased.

Significance: A low-load plyometric intervention which resulted in significant goal attainment in children with CP had no overall effect on running kinematics as measured by the GPS. Future studies should be powered according to both GMFCS level and distribution (unilateral vs bilateral CP).