## 3 Results
### Kinematic Data Analysis Results
#### 3.1.3 Temporal Kinematic Analysis Results  
Table 3 summarizes the results for the two temporal analyses performed. For healthy participants, all kinematic synergies showed significant differences as the test condition and time had an effect on all of them (there is a temporal pattern), except for thumb flexion/extension. This effect of time was significantly influenced by the test condition, meaning that there is a distinct temporal pattern depending on whether the test is performed in the real or virtual environment, except for thumb abduction. For patients, only abductions were not affected by the test condition. Unlike healthy participants, SCI patients showed no consistent temporal patterns in kinematic synergies (time had no effect), likely due to the underlying pathology or the small sample size. During RBBT, significant differences due to health condition were found only for fingers' PIP flexion and abduction. A temporal pattern was identified for all kinematic synergies (time had an effect on them), except for abductions, with this time effect significantly influenced by the health condition. In VBBT, health condition differences were noted only in thumb and finger PIP flexion. Similarly, a temporal pattern was identified for all kinematic synergies, except for thumb abduction, with this time effect influenced by health condition. Figures 4 and 5 illustrate the temporal evolution (mean and SD) of the kinematic synergies, alongside post-hoc results for differences at each frame between groups for the two temporal analyses performed. Four movement phases have been considered in all time plots: cube transport (a), cube release (b), hand return (c), and cube reach (d). Each graph of Figure 4 compares test conditions, while in Figure 5, the graphs compare health conditions. For healthy participants, the temporal evolutions shown in Figure 4 align with a kinematic pattern for each test condition (RBBT and VBBT), except for _Thumb_F(T)_, according to the results in Table 3. For patients, the time evolution shown in Figure 4 does not correspond to any specific temporal pattern. However, the figure shows that the temporal evolutions of the patients differ from those of the healthy individuals, especially in the case of VBBT in _Thumb_F(t)_ and _PIPS_F(t)_, particularly during the initial transport phase and in cube reaching. Differences found due to the test condition globally in both health condition groups (Table 3) are reflected at each frame, except in _MCPs_F(t)_ during the hand  
Figure 3: (**a**) Box-and-whiskers plots of the two kinematic parameters (_M_: median and _R_: range) for the five kinematic synergies (_Thumb_F_, _MCPs_F_, _PIPs_F_, _Thumb_A_, _Fingers_A_) for healthy (**left**) and patient (**right**) groups. (**b**) Plots of these parameters for real (**left**) and virtual (**right**) BBT. Significant differences (\(p<0.05\)) are marked with an asterisk * after the name of the variable. returning phase. Surprisingly, no phase-wise differences were observed in _Thumb_F(t)_ among patients, possibly due to the small sample size. Figure 4: Mean and standard deviation of kinematic synergies over time for each health condition group. To indicate statistical differences at each frame, a small green asterisk (*) is shown in the upper area of the figure in accordance with the legend. Due to the figure size, asterisks may appear as small dots, and if differences occur across consecutive frames, they may resemble line segments. If no global differences due to test condition (RBBT/VBBT) are observed across participants (Table 3), no asterisks indicating significant differences at each frame between groups are displayed. Time has been divided into four phases: _Cube Transport_ (a), _Cube Release_ (b), _Hand Return_ (c), and _Cube Reach_ (d). Figure 5: Mean and standard deviation of the kinematic synergies over time for each test condition group. To indicate statistical differences at each frame, a small green asterisk (*) is shown in the upper area of the figure in accordance with the legend.