Association between sensorimotor function and functional and reactive balance control in the elderly.
OBJECTIVE
Postural disturbances can arise from performing functional tasks and from external perturbations. Identification of sensorimotor factors associated with both types of balance control in the elderly can help us to understand better the balance problems facing older adults.


METHODS
Cross-sectional.


METHODS
Healthy young, stable older, and functionally unstable older adults with 16 participants in each group.


METHODS
Clinical vibration sense and muscle strength of the lower extremity, and functional balance (FB) tests were conducted. The timing and amplitude of the reactive postural muscle responses of the leg postural muscles, recorded from standing subjects following support surface backward translation, were also examined.


RESULTS
Young and older subjects differed significantly in the amplitude of their postural muscle responses, while the two older groups differed significantly in muscle strength and FB. When age was controlled, the strength of the ankle dorsi- and plantar-flexors was the only significant predictor for FB. For reactive postural muscle responses, none of the sensorimotor factors was significant.


CONCLUSIONS
Functional and reactive balance abilities differed in their associating factors. The difference in the patterns of association for functional and reactive balance implies the need for separate assessment for these two categories of balance control clinically.
Lin
Sang-I
SI
Department of Physical Therapy, National Cheng Kung University, No 1 Ta-Hsueh Rd, Tainan, Taiwan 701. lin31@mail.ncku.edu.tw
Woollacott
Marjorie
M
D000328:Adult; D000367:Age Factors; D000368:Aged; D001696:Biomechanical Phenomena; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D009142:Musculoskeletal Physiological Phenomena; D017933:Peripheral Nervous System / Q000502:physiology*; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D011597:Psychomotor Performance