## 2 Materials and Methods
### Instruments and Procedures
#### 2.3.6 Kinematic Assessment  
The Qualisys Motion Capture System 2021.2 from Qualisys AB(r), Gothenburg, Sweden, was used to assess the head and spine kinematics during the FRT and in the one-minute standing position test. This system included 13 cameras, (8 Oqus and 4 Miqus, operating with a sampling rate of 100 Hz, and 1 Miqus video camera, operating with a sampling rate of 25 Hz). Based on the studies of [PERSON] et al. (2015) and [PERSON] et al. (2011), to evaluate the kinematics of the cervical spine in the sagittal plane, a set of three reflective markers were placed unilaterally on the dominant side of the lateral orbital margin (LOM), the tragus of the ear (TRG), and the seventh cervical spinous process (C7) [31; 32]. Based on the study by [PERSON] et al. (2022), a set of six reflective markers were placed on the spinous processes of the first, third, and eleventh thoracic vertebrae (T1, T3, and T11) as well as at the first and fourth lumbar vertebrae (L1 and L4) and the second sacral verteb (S2) to assess the kinematics of the thoracic and lumbar curvature and sacral tilt in the sagittal plane [33] (Figure 1) [34; 35; 36; 37; 38; 39; 40; 41].  
Finally, a marker was placed in the third metacarpophalangeal joint (3-MCF) to measure the distance traveled by the dominant arm in space when the participant reached forward.  
\begin{table}
\begin{tabular}{p{113.8 pt} p{284.5 pt}} \hline \hline
**Type** & **Definition** \\ \hline Type I (Inferior angle) & At rest, the scapula’s inferior angle is posteriorly prominent. During arm motion, the inferior angle tilts dorsally, and the acromion tilts ventrally over the top of the thorax. The axis of the rotation is in the horizontal plane [30]. \\ \hline Type II (Medial border) & At rest, the scapula’s medial border is prominent dorsally. During arm motion, the medial scapular border tilts dorsally off the thorax. The axis of the rotation is vertical in the frontal plane [30]. \\ \hline Type III (Superior border) & At rest, the superior border of the scapula may be elevated, and the scapula can also be anteriorly displaced. During arm motion, a shoulder shrug initiates movement without significant winging of the scapular occurring. The axis of this motion occurs in the sagittal plane [30]. \\ \hline Type IV (Symmetric scapulohumeral) & At rest, the position of both scapulae is relatively symmetrical, considering that the dominant arm may be slightly lower. During arm motion, the scapulae rotate symmetrically upward such that the inferior angles translate laterally away from the midline and the scapular medial border remains flush against the thoracic wall. The reverse occurs during the lowering of the arm [30]. \\ \hline \hline \end{tabular}
\end{table}
Table 1: Scapular Dyskinesia Type Characterization.  
The setup of markers was standardized across all participants to reduce the individual variation of the placement of markers.  
A single force plate [model FP4060-08 connected to amplifier AM 6300 Bertec Corporation (Columbus, OH, USA) and an analog board b from Qualisys AB(r), Gothenburg, Sweden] with a sampling frequency of 1000 Hz was used to assess CoP displacement and velocity in both the anteroposterior (CoPAP) and mediolateral (CoPML) directions. The participant's foot position on the platform was also initially established to standardize individually and comfortably the participant position for each evaluation.  
Before each participant evaluation, the Qualisys Motion Track Manager System and the Bertec force plate were calibrated [42].