Balance control in the elderly: implications for clinical assessment and rehabilitation.

Deterioration of balance control system with age results in a higher incidence of falls. To assess the performance of the balance control system we need to select appropriate body posture and/or motion, decide on the type and level of perturbation and study the response using selected measures. The guidelines we should use to determine the task, perturbation and measures is the focus of this article. Our work on the elderly is used to provide support for the various criteria put forward. The tasks evaluated for stability should include specific postures and movements which are part of the normal repertoire and challenge the balance control system. Variety of perturbations are necessary to get insights into the working of the system. The level of perturbation that can be handled should be specified. The response measures should be able to identify deterioration in the system performance, provide diagnostic information and insights into how the system has adapted to the age-related changes. These guidelines are critical if balance tests are to be used for clinical assessment and rehabilitation.