# 3D Ultrasound Mosaic of the Whole Shoulder: A Feasibility Study
## 5 Conclusions  
In this study, we proved that it is feasible to reconstruct a US mosaic of a full in vivo rotator cuff using manual registration of overlapping 3D US images. Anatomical structures including bones, muscles, tendons, ligaments and joints in the US mosaic were assessed and their visibility was graded by two experienced clinical sonographers. The sonographers agreed on the clinical viability of visualising the bony anatomy and the potential of other MSK anatomies with further optimisation of the registration, compounding and imaging approaches. An MRI segmented for bones aided in the identification of anatomy, and muscle segmentations were unnecessary. We also proved that anatomical geometries were preserved in the reconstructed mosaic by comparing thicknesses of known surfaces and distances between anatomical structures inside the US mosaic and validating the measurements against an original US volume and the MRI data. The results suggest that there is potential for the US mosaic to be used as an educational tool for assessing rotator cuff conditions.  
Conceptualization, D.F. and P.P.; methodology, A.S., M.A. and M.S.; software, A.S., M.A. and M.S.; validation, A.S., M.A. and M.S.; formal analysis, A.S., J.R. and M.S.; investigation, A.S., M.A. and M.S.; resources, A.G., K.C., D.F. and P.P.; data curation, A.S., M.A., J.R. and M.S.; writing--original draft preparation, A.S.; writing--review and editing, A.S., D.F., K.C., P.P., A.G., M.A., J.R. and M.S.; visualization, A.S., M.S. and D.F.; supervision, D.F., M.A. and P.P.; project administration, D.F., M.A. and P.P.; funding acquisition, D.F., M.A. and P.P. All authors have read and agreed to the published version of the manuscript.  
This research was supported by funding schemes of the Australian Government: ARC Industrial Transformation Training Centre (ITTC) for Joint Biomechanics under grant IC190100020.  
This study was conducted in accordance with the Declaration of Helsinki and approved by the Human Research Ethics Committee of QUT (No. 1700001110 on 20 April 2022).  
Informed Consent Statement:Informed consent was obtained from all subjects involved in this study.  
Data Availability Statement:Data are available upon request with the exception of those limited by privacy and ethical restrictions.  
The authors would like to acknowledge [PERSON] and [PERSON] for sharing the MRI data and segmentations used in this work.  
The authors declare no conflicts of interest.  
\begin{table}
\begin{tabular}{l c c c} \hline \hline
**Structure Demonstration** & & & \\ \hline
**Anatomy** & **US Image** & **US/MRI Bone Image** & **US/MRI Muscle Image** \\ \hline
**Tendons** & & & \\ \hline Biceps & & & \\ \hline Subscapularis & & & \\ \hline Supraspinatus & & & \\ \hline Infraspinatus & & & \\ \hline Teres Minor & & & \\ \hline _Muscles_ & & & \\ \hline Infraspinatus & & & \\ \hline Teres Minor/Major & & & \\ \hline \hline \end{tabular}
\end{table}
Table 1: Cont.  
\begin{table}
\begin{tabular}{l c c c} \hline
**Structure Demonstration** & & & \\ \hline
**Anatomy** & **US Image** & **US/MRI Bone Image** & **US/MRI Muscle Image** \\ \hline Supraspinatus & & & \\ \hline Trapezius & & & \\ \hline Deltoid & & & \\ \hline Subacromial/subdeltoid & & & \\ Bursa & & & \\ \hline _Ligaments_ & & & \\ Coracoacromial & & & \\ \hline Coracoacromial & & & \\ \hline Coracoacromial & & & \\ \hline Coracohomeral & & & \\ \hline \end{tabular}
\end{table}
Table 1: Cont.  
**Figure A1.** Humeral head surface thickness measurements acquired for a single US volume (6 points/plane for all 3 planes).  
**Figure A2.** Humeral head surface thickness measurements acquired for a single US volume (12 points/plane for all 3 planes).