Many patients with "whiplash syndrome" experience unrelenting neck stiffness and pain. This abnormal muscular tension is postulated to be causally related to a central disorder of postural control, which has evolved secondary to injury of the inner ear labyrinthine structures. Moving platform posturography was used to demonstrate the presence or absence of a static or dynamic equilibrium disorder in 48 patients who had experienced the oscillation forces induced by a rear-end automobile collision. Other vestibular tests were used to document dysfunction of the semicircular canals and the otolith structures. A high percentage of patients were found to have faulty inner ear functioning leading to inefficient muscular control of balance and erect posture. Active perilymph fistulas were identified at surgery in seven patients.