## 5 Conclusions  
The results obtained in the present study show that the paretic shoulders of post-stroke patients displayed (i) a decreased scapular posterior tilt during flexion and abduction of the paretic shoulder and (ii) a lower SHR during all measured arm movements. Moreover, we found (iii) that the FMA was correlated with the scapular anterior-posterior tilt at 60\({}^{\circ}\) and 90\({}^{\circ}\) of shoulder abduction. These findings are relevant from a rehabilitative point of view since they make it possible to understand the role of scapulothoracic motion in shoulder kinematics and, possibly, to intervene with treatments for restoring muscle tone around the scapula.  
Clinical scores normally used to evaluate function give information correlated with kinematics but are time-consuming and not sensitive to scapulothoracic motion. MIMUs allow for rapid, accurate, and ecological analysis of shoulder movement, succeeding in highlighting scapular rotation in relation to the flexion and abduction of the shoulder. In the literature, wearable devices have mainly been used to monitor the effects of rehabilitation on hemiplegic shoulders, while clinical decision making requires an objective assessment of shoulder impairment. The present pilot study described a validated and reliable wearable system to test shoulder scapulothoracic and glenohumeral 3D kinematics, including SHR assessment in stroke patients.  
The scope of this study was to evaluate the feasibility of measuring 3D shoulder complex kinematics (glenohumeral and scapulothoracic motion) during the active flexion and abduction of the paretic arm in individuals with stroke using MIMUs, compare it with healthy patients, and correlate instrumental measurements with clinical-functional measurements.  
Our study has some limitations: a control group without matching age to the post-stroke group; the inclusion of patients with different arm function; the small sample and the heterogeneous onset of stroke (subacute and chronic); and the lack of an electromyographic evaluation performed in association with the kinematics assessment.  
A future study of paretic arm shoulder function in stroke should be carried out with a larger number of hemiplegic patients, an adequate control group, and controlled clinical variables in order to permit a stronger statistical analysis. Moreover, the combination of an electromyographic evaluation to identify specific muscle dyskinesia will help in the study and treatment of hemiplegic shoulders.  
Conceptualization: M.L. and M.G.B.; methodology: M.L. and M.G.B.; formal analysis: M.G.B.; investigation: M.L.; data Collection: M.M., S.C. and G.P.; writing--original draft preparation: M.L. and D.D.; writing--review and editing: M.L., L.C., M.G.B. and D.P.; visualization. D.P.; supervision: M.G.B. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
This study was conducted according to the guidelines of the Declaration of Helsinki. As a pilot study for feasibility, no approval by the local Ethics Committee was requested. The data obtained were used to write a research protocol to be submitted to the Ethics Committee.  
Informed Consent Statement: Informed consent was obtained from all subjects involved in this study.  
The data supporting the reported results can be obtained from the corresponding author upon reasonable request.  
We would like to acknowledge and thank [PERSON], [PERSON], [PERSON], and [PERSON] of the NCS Lab., Carpi (MO), Italy, for their technical support in collecting data, [PERSON] Stat. Eng. for the statistical analyses, and [PERSON] Eng. for their useful comments.  
The authors declare no conflict of interest.