Effect of percutaneous electrical stimulation on ankle kinematics in children with cerebral palsy

Percutaneous intramuscular electrodes were implanted operatively into the tibialis anterior (TA) and gastrocnemius (GA) muscles of four children with cerebral palsy. An electrical stimulator was programmed to provide electrical stimulation at appropriate times using force-sensing foot switches to detect gait phase transitions. Participants practiced using the electrical stimulation under three randomly ordered conditions (GA on, TA on, and both GA and TA on). Immediately after a week of practice, a standard three-dimensional gait analysis was conducted for the practiced stimulation condition and without stimulation. Significant improvements in the degree of dorsiflexion at initial contact and the peak dorsiflexion in swing were found when comparing the TA only on and both TA and GA on conditions to off conditions. No changes were found in degree of dorsiflexion at initial contact and the peak dorsiflexion in swing were when comparing the GA only on and GA only off conditions. Preliminary data suggest that percutaneous functional electrical stimulation of the TA applied during walking improved the position of the foot at initial contact and during the swing phase of gait.