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NASA NTRS · 20040141961

Dynamic balance control in elders: gait initiation assessment as a screening tool

Chang, H.·Krebs, D. E.·Wall, C. C.
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Abstract

OBJECTIVE: To determine whether measurements of center of gravity-center of pressure separation (CG-CP moment arm) during gait initiation can differentiate healthy from disabled subjects with sufficient specificity and sensitivity to be useful as a screening test for dynamic balance in elderly patients. SUBJECTS: Three groups of elderly subjects (age, 74.97+/-6.56 yrs): healthy elders (HE, n = 21), disabled elders (DE, n = 20), and elders with vestibular hypofunction (VH, n = 18). DESIGN: Cross-sectional, intact-groups research design. Peak CG-CP moment arm measures how far the subject will tolerate the whole-body CG to deviate from the ground reaction force's CP; it represents dynamic balance control. Screening test cutoff points at 16 to 18 cm peak CG-CP moment arm predicted group membership. RESULTS: The magnitude of peak CG-CP moment arm was significantly greater in HE than in DE and VH subjects (p<.01) and was not different between the DE and VH groups. The peak CG-CP moment arm occurred at the end of single stance phase in all groups. As a screening test, the peak moment arm has greater than 50% sensitivity and specificity to discriminate the HE group from the DE and VH groups with peak CG-CP moment arm cutoff points between 16 and 18 cm. CONCLUSIONS: Examining dynamic balance through the use of the CG-CP moment arm during single stance in gait initiation discriminates between nondisabled and disabled older persons and warrants further investigation as a potential tool to identify people with balance dysfunction.

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NASA Discipline NeuroscienceNon-NASA CenterGaitDisabled PersonsVestibular Diseases/physiopathologyMusculoskeletal EquilibriumSupport, U.S. Gov't, Non-P.H.SCross-Sectional StudiesSupport, U.S. Gov't, P.H.SHumanSupport, Non-U.S. Gov'tSensitivity and SpecificityAged

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Chang, H., Krebs, D. E., Wall, C. C.. 1999-05-01. Dynamic balance control in elders: gait initiation assessment as a screening tool. https://ntrs.nasa.gov/citations/20040141961

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