EP140 Simplifying ultrasound suprascapular notch exploration for regional anesthesia

<h3>Background and Aims</h3> The suprascapular notch (SSN) exhibits various shape, and several classifications have been proposed. Ultrasounds notch recognition is essential for performing effective approach and safe block. The objective of our study is to evaluate the ultrasound characteristics of the suprascapular notch with the goal of simplifying ultrasound exploration. <h3>Methods</h3> We performed ultrasonography of the shoulder in 108 healthy Caucasian volunteers. According to Rengachary classification, we classified notches into 5 types and measured dimensions. We measured the superior transverse diameter (STD) and the maximal depth of the SSN. <h3>Results</h3> 206 scapulae were considered. In 5 volunteers, the notch was non visible, obscured by the clavicle. Results were presents in the table 1. Nonparametric tests did not reveal any impact of age, sex, weight, or height on notch type. The repartition of notch types was statistically similar between the left and right sides (p &lt; 0.001). <h3>Conclusions</h3> Types II, III and IV are the more representatives notch types with a typical U- or V-shape. Anatomy variations, poor consensus of different classification and sonoanatomy visualization made suprascapular notch identification difficult for anesthetist. Precise determination of type of notch is poor of interest for anesthesiologist. However, we must know that notch identification may present two main general characteristics ; essential for his identification. Once is an absent or a very discrete notch as a wide depression. The second is the commonly known notch, identifiable as a bone depression. We propose an easy practical identification for ultrasounds classification base on presence or ‘absence’ of notch in order to facilitate practical approach for anesthetist during regional anesthesia (figure 1).