Article

Purpose: To evaluate lower extremity mechanics and muscle activation
associated with the sit-to-stand transfer using a portable lifting-seat device
and to compare these data to an unassisted transfer in healthy young and older
adults. Methods: Bilateral lower extremity and low back musculature
electromyography, three-dimensional leg and trunk motion, and ground reaction
forces were recorded from 10 young (mean age = 25) and 10 older (mean age = 69)
adults during five trials of (i) no assist and (ii) assisted transfers. Data were
time normalized to represent the period of seat-off to standing. Peak sagittal
plane joint angles, moments, and muscle activity profiles were calculated.
Analysis of variance models was used to test for main effects and interactions
(alpha = 0.05). Results: Trunk, hip, and knee angles were significantly reduced
and dorsiflexion increased with assisted transfer (p < 0.05). Peak hip and ankle
joint moments were reduced (p < 0.05) and no change found in knee moments (p >
0.05). Peak muscle activity was lower during the assisted transfer (p < 0.05).
Seat device effects were similar between age groups. Older adults used higher
relative muscle activation. Conclusion: Variables indicative of sit-to-stand
functional demand were reduced with lifting-seat device use. Data provide a
framework for future recommendations on product prescription, use, and research
pertaining to the advancement of adaptive seating. Implications for
Rehabilitation Hip and trunk mechanical demands, and muscle activation were
reduced with portable lifting seat device use. Greater ankle dorsiflexion was
found with portable lifting seat device use, suggesting this range of motion
should be considered when prescribing this device. Healthy older and younger
adults used similar knee and trunk joint mechanics yet older adults completed the
sit-to-stand trials with greater lower extremity and low back muscle activation.

Langue : ANGLAIS