Table 2.
Kinematic characteristics of reach-to-grasp movement.
| Intraoperative MED OFF | Postoperative (subgroup patients) STIM OFF MED OFF |
Postoperative (subgroup patients) STIM ON MED OFF |
|
|---|---|---|---|
| Mean ± SD | Mean ± SD | Mean ± SD | |
| Reach-to-grasp movement | |||
| V max (m/s) | 0.25 ± 0.08 | 0.29 ± 0.13 | 0.33 ± 0.11 |
| Total MT (s) | 1.22 ± 0.23 | 1.25 ± 0.41 | 1.07 ± 0.36 |
| MT ACC (%) | 36.75 ± 8.58 | 36.89 ± 3.77 | 39.09 ± 4.09 |
| MT DEC (%) | 63.25 ± 8.58 | 63.11 ± 3.77 | 60.91 ± 4.09 |
| MT PGA (%) | 70.76 ± 4.26 | 74.13 ± 7.03 | 68.50 ± 3.63 |
| Distance PGA-MGA (mm) | 20.14 ± 7.96 | 19.90 ± 0.80 | 25.61 ± 5.36 |
The table demonstrates mean and standard deviation (SD) of the kinematic parameters of the reach-to-grasp movement in all 12 patients tested intraoperatively (first column) and in a subgroup of three Parkinson’s disease patients who were tested additionally postoperatively without (second column) and with subthalamic stimulation (third column). MED OFF: without antiparkinsonian medication. STIM OFF MED OFF: without deep brain stimulation and without antiparkinsonian medication. STIM ON MED OFF: with deep brain stimulation but without antiparkinsonian medication. V max (m/s): maximal velocity of the hand wrist during the reaching phase. Total MT (s): total movement time calculated from the velocity curve of the hand wrist from the beginning (V > 0.05 m/s) to the end (V < 0.05 m/s) of the reaching phase. MT ACC (%): acceleration time from the beginning of the movement (V > 0.05 m/s) to the time when maximal velocity is reached expressed as percentage of the total movement time. MT DEC (%): deceleration time from the time of maximal velocity to the end of the movement (V < 0.05 m/s), calculated as percentage of the total movement time. MT PGA (%): movement time from the beginning of the movement (V > 0.05 m/s) to the time when maximal peak grip aperture between thumb and index finger is reached as percentage of the total movement time. Distance PGA-MGA (mm): difference between the maximal and minimal distance between thumb and index finger during the grip formation. The movement kinematics intraoperatively were comparable to those in the postoperative OFF condition, subthalamic stimulation improved mainly the velocity during the reaching phase.