Effect of whole-body vibration on quadriceps spasticity in individuals with spastic hypertonia due to spinal cord injury.
OBJECTIVE
Individuals with spinal cord injury (SCI) often have involuntary, reflex-evoked muscle activity resulting in spasticity. Vibration may modulate reflex activity thereby decreasing spasticity. This study suggests feasibility of using whole-body vibration (WBV) to decrease quadriceps spasticity in individuals with SCI.


METHODS
Participants were individuals (n=16) with spastic quadriceps hypertonia due to chronic SCI (> 1 year). Quadriceps spasticity was measured by gravity-provoked stretch (Pendulum Test) before (initial) and after (final) a 3 day/week, 12-session WBV intervention. In addition, differences between immediate (immediate post-WBV) and delayed (delayed post-WBV) within-session effects were quantified. Finally, we assessed response differences between subjects who did and those who did not use antispastic agents.


RESULTS
There was a significant reduction in quadriceps spasticity after participation in a WBV intervention that persisted for at least eight days. Within a WBV session, spasticity was reduced in the delayed post-WBV test compared to the immediate post-WBV test. The WBV intervention was associated with similar changes in quadriceps spasticity in subjects who did and those who did not use antispastic agents.


CONCLUSIONS
Vibration may be a useful adjunct to training in those with spasticity. Future studies should directly compare the antispastic effects of vibration to those of antispastic agents.
Ness
Lanitia L
LL
University of Miami, Miami, FL, USA.
Field-Fote
Edelle C
EC
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D004576:Electromyography / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009122:Muscle Hypertonia / Q000209:etiology / Q000534:rehabilitation*; D052097:Quadriceps Muscle / Q000503:physiopathology*; D012026:Reflex, Stretch / Q000502:physiology; D013119:Spinal Cord Injuries / Q000150:complications / Q000534:rehabilitation; D016896:Treatment Outcome; D014732:Vibration