During her presentation at the international symposium on Rehabilitative Ultrasound Imaging (RUSI), which was held in Madrid June 2016, Cliona O’Sullivan discussed the reliability, validity and clinical applications of RUSI of the scapular muscles. She concluded that, correctly used, RUSI is a valid and reliable tool to examine the lower trapezius (LT) muscle. Examining the serratus anterior (SA) muscle was found to be more difficult, and further research is necessary.