Children will receive hippotherapy by a licensed physical therapist. Before riding, stretching and warming exercises of the adductor muscles will be performed. Later, the patient will be seated astride with the therapist behind. In any case, the participant had no control of the horse. Therapist will be responsible for correctly positioning the subject on the horse, but no position changes or active intervention of the subject with the therapist will be made. This positioning consists on achieving the optimal body alignment with neutral pelvis.

Children will receive the conventional treatment, based on physiotherapy related techniques, such as neurodevelopmental treatment (twice a week).

Children will receive the hippotherapy treatment, based on horse walking in a regular way led by an experienced leader. Sessions will be performed for 45 minutes once weekly for 12 consecutive weeks in an indoor riding area.

The aim of the scale is to assess muscle tone by the joint range of motion, manually evaluated, and clinically recording passive movements' resistance. Each participant will be examined lying supine on a couch in a relaxed position. The MAS scale is, undoubtedly, the most widely used measure for the quantification of muscular hypertonia. The trunk and the head will be maintained in a neutral position to avoid eliciting tonic neck reflexes, and the passive speed movements will be made in the course of one second. It will be performed in left and right hip, independently, 5 to 8 times to obtain a more reliable result. This modified version adds a 1+ scoring category, in order to register resistance in less than half of the range of motion. Thus, the scores range is from 0 to 4, with 6 choices.