Article

After amputation, the sensorimotor cortex reorganizes, and these
alterations might influence motor functions of the remaining extremities.
The authors examined how amputation of the dominant or nondominant
upper or lower extremity alters deftness in the intact limbs. METHODS: The
participants were 32 unilateral upper- or lower-extremity amputees and 6
controls. Upper-extremity deftness was tested by coin rotation (finger deftness)
and pegboard (arm, hand, and finger deftness) tasks. RESULTS: Following
right-upper- or right-lower-extremity amputation, the left hand's finger
movements were defter than the left-hand fingers of controls. In contrast, with
left-upper- or left-lower-extremity amputation, the right hand's finger
performance was the same as that of the controls. CONCLUSIONS: Although this
improvement might be related to increased use (practice), the finding that
right-lower-extremity amputation also improved the left hand's finger deftness
suggests an alternative mechanism. Perhaps in right-handed persons the left motor
cortex inhibits the right side of the body more than the right motor cortex
inhibits the left side, and the physiological changes induced by right-sided
amputation reduced this inhibition.

Langue : ANGLAIS