Balance issues at the time of injury is the top risk factor to prolonged concussion. The sensory system provides the leading contribution to the sensse of baland and spatial orientation for the purpose of coordinating movement with balance. The vestibular system sends signals primarily to the neural structures that control eye movements, and to the muscles that keep people upright. The brain uses information from the vestibular system in the head and from proprioception throughout the body to understand the body's dynamics and kinematics (including its position and acceleration) from moment to moment. This requires assessment by a properly trained practitioner.