Therapeutic Effects of an Anti-Gravity Treadmill (AlterG) Training on Neuromuscular Abnormalities Associated with Spasticity in Children with Cerebral Palsy

We aimed to characterize the therapeutic effects of Anti-Gravity Treadmill (AlterG) Training on neuromuscular abnormalities associated with spasticity in children with cerebral palsy (CP). Eighteen subjects were divided into two groups; AlterG and control. All subjects received up to 40 minutes of training 3 times a week for 8 weeks. The control group received conventional occupational therapy. The advanced parallel-cascade system identification technique was used to characterize the neuromuscular abnormalities associated with spasticity and separated its intrinsic and reflex components. Reflex stiffness gain (GR) and intrinsic stiffness gain (K) were used to track the therapeutic effects of training on neural and muscular abnormalities. Both K and GR were strongly positioned dependent; they varied linearly with the ankle angle at dorsiflexion. Their position dependence was quantified by fitting a linear model to K and GR over dorsiflexion positions. The evaluations were performed at four-time points; i.e. the baseline (before starting the training), 1 and 2 months after starting the training, and 1 month after the completion of the training to assess the persistent effects. We determined the changes in K and GR intercept and slope parameters over these 3 months to evaluate the therapeutic effects of training on neuromuscular abnormalities. The results revealed that all K and GR parameters decreased substantially following using AlterG training and these changes were greater than those observed in the control. The results also showed that these therapeutic effects were persistent to a high extent, particularly in the AlterG group. Our findings suggested that AlterG training could be considered as a robust therapeutic intervention to reduce neuromuscular abnormalities and manage spasticity.