Article

The grip-lift task enables a quantitative assessment of grasping ability.
Patients are regularly assessed in a supine position, which offers a different
view of the grasped object from that in the sitting position. To our knowledge,
no data are currently available on the influence of posture and vision on
grip-lift task parameters. We therefore aimed to determine the effects of posture
and vision on these parameters. Twenty-six healthy right-handed adults performed
grip-lift tasks with a manipulandum that measured different temporal and dynamic
parameters in four conditions: sitting eyes open, sitting blindfolded, lying down
eyes open and lying down blindfolded. A repeated-measures analysis of variance
with two factors (vision and position) showed that the absence of vision affected
all the parameters measured. The lying down position increased the time between
the first contact with the object and the modification of the vertical force as
well as the delay between the first increase of the horizontal force and the
increase of the vertical force. In addition, there was a lower adaption of the
horizontal force, required to squeeze the object, to the vertical force. Finally,
the interaction of position and vision was associated with significant
differences in the delay between the contact of each digit with the object, the
maximum horizontal force and the ratio between the horizontal and vertical force
during a static holding period. Both position and vision appear to affect the
grip-lift task. Consequently, sequential assessments should be performed in the
same condition to obtain reliable data.

Langue : ANGLAIS