Box plot of the percentage variation of some functional hand parameters at the end of the trial (T2) with respect to the beginning of it (T0). Median is highlighted, crosses represent statistical outliers. All the measurements were performed with the device. CTorque: clockwise rotation torque; ATorque: anticlockwise rotation torque; 1st–4th Force: fingers force in opposition to the thumb. Statistically significant improvements of the parameters have been marked with asterisks.