Posture in otoneurology. Volume I.

In this study, posture is studied in the context of neuro-otological problems. In the several chapters, postural elements, postural influence upon balance aspects as well as postural components of the balance function in normal and pathological conditions are emphasized. Two main applications are put forward: rehabilitation by postural treatment techniques (REHAB) and examination techniques for the vestibulospinal aspects (posturography--PG). I. Balance function Balance is provided by automatic reflexes for stabilization of the visual field (vestibulo-ocular reflex--VOR) and for a correct posture, erect standing (vestibulo-spinal reflex--VSR) and head position (vestibulo-collic reflex--VCR). The fundamental characteristics of these reflexes are described, especially of those related to posture. The reflexes are elaborated on the basis of sensory inputs that inform about changed relations to space and environment, provided by visual, vestibular and proprioceptive systems. The sensory signals are further processed by the centers to adequate reflexes and to some extent to a conscious awareness. II. Dysfunction and adaptation Dysfunction in the balance mechanisms leads to erroneous reflexes, but most importantly to frightening sensations of vertigo. The peripheral disturbances produce a sensory mismatch which is the primum movens of vertigo. Built-in adaptive mechanisms cope with this disturbance and restore global balance function. The mechanisms involved have been studied as vestibular compensation and habituation, VOR-reflex plasticity and sensory "substitutive" compensation. The mechanisms are set into action by the dysfunctional situation and constitute an error-controlled process. Emphasis is laid upon the items related to rehabilitation treatment and posturography. A survey of clinical entities of vestibular peripheral dysfunction is included. III. Examination techniques The logical approach to the patient with vertigo consists in an analysis of the complaints pattern, correlation of it with the dysfunctional state revealed by clinical observation, and functional tests of balance. Correct interpretation of the test results is a pre-requisite. Postural aspects of these examination techniques, especially posturography, are put into evidence in this review. The strategy used in the department is sketched. IV. Contribution of the examination techniques: functional evaluation results The several data obtained by each examination technique are discussed within the scope of the experiences in the department. Data from the literature and from personal experience, especially interpreted in the context of rehabilitation and posturography, are analysed. V. Reh