Abstract: A system for assessing soft-tissue injury in a subject. The system comprises means for applying energy internally to tissue of the subject in an inaudible and invisible manner, with no indications to the epidermal tissue of the subject as to when energy is being applied or how much energy is being applied. The applying means has an energy control mechanism for varying parameters of energy application. The system also comprises a subject response unit having input means controlled by the subject in accordance with perceived sensation in tissue acted upon by the energy applying means. The system also includes also data recording means for simultaneously recording parameters of energy application from the energy applying means and parameters of perceived sensation from the subject response unit. With the system, application of energy occurs invisibly and inaudibly at an internal level. The tissue is stimulated from within by the energy.