Components of postural dyscontrol in the elderly: a review.

The concept of a generalized aging effect on a generalized balance mechanism is discussed, and an alternative, multicomponent approach to understanding the heterogeneity of postural dyscontrol in the elderly is presented. Neural sensorimotor components of normal postural control mechanisms are identified and discussed. The effects of Parkinson's disease, hemiplegia, cerebellar degeneration, peripheral vestibular loss, and other disorders on the components of postural control are summarized. Quantitative posturography is advocated to detect preclinical manifestation of multiple musculoskeletal and neuromuscular pathologies and reduced compensatory abilities in posturally unstable elderly adults.