Role of Armeo-Power and Muscle Vibration in Upper Limb Rehabilitation

All the subjects assigned to the experimental received a focal belly-muscle vibration on the spastic antagonist muscles (i.e. triceps brachialis-TB, deltoid-DE, and supraspinatus-SS) during shoulder abduction and elbow extension. MV was delivered by a pneumatic vibrator powered by compressed air (Vibraplus; @Circle, San Pietro in Casale, Italy) (fig. 2) wired to appropriate-muscle probe diameter (up to 2cm2). MV was set at a frequency of 80Hz and an individually adjusted vibration amplitude (approximately 2mm in indentation depth, mean pressure of 250mBar, which effectively induce inhibition of the monosynaptic reflex) so that it was just below the threshold for perceiving an illusory movement. We chose such set up to avoid any signs of muscle contraction potentially reflecting either possible voluntary movement or occurrence of the tonic vibration reflex (TVR).