Long-term effects of robotic hippotherapy on dynamic postural stability in cerebral palsy

Background: Dynamic postural instability is a common neuromuscular impairment in cerebral palsy (CP), which often includes balance dysfunction and an associated risk of serious falls. Robotic hippotherapy has recently become a widespread clinical application to facilitate postural core stabilization, strength, and endurance through repetitive vestibular and proprioceptive stimulation to the spine via the sensorimotor system pathways. However, the long-term effects of robotic hippotherapy on dynamic postural instability in CP remain unclear. Objective: To examine the long-term effects of robotic hippotherapy on dynamic postural stability in CP. Methods: An advanced three-dimensional biomechanical eight-camera video motion capture (VMC) system was used to compute the center of mass (COM) pathway, which represents intervention-related spinal core instability. The robotic hippotherapy system was used to improve dynamic postural stability and associated balance performance. Robotic hippotherapy exercise was provided for 45 minutes/session, 2-3 times a week over the 12-week period. Results: Abnormal mean COM pathway length, standard deviation, and range substantially decreased after 12 weeks of robotic hippotherapy. The initial x-axis COM was greater than that of the y-axis. However, the amount of abnormal anterior-posterior and medio-lateral postural sway substantially decreased after robotic hippotherapy. Conclusions: This study provides the first compelling evidence that the robotic hippotherapy is safe and effective for postural instability control and sitting balance dysfunction that mitigates the risk of falls in CP.