Description and ultrasound targeting of the origin of the suprascapular nerve

Abstract

Anatomical variations in the suprascapular nerve (SSN) and its depth in the suprascapular notch can make it difficult to target with ultrasonography (US). One alternative could be a proximal approach to the SSN, if US provides a reliable description of its origin (orSSN). The primary objective of this study was to demonstrate that US can reliably locate the orSSN. The secondary objective was to describe the features of the proximal SSN. Seventy brachial plexuses (BPs) from 30 healthy volunteers (60 BPs) and 5 cadavers (10 BPs) were included. There were two parts to this study: (1) description of the proximal SSN in healthy volunteers using US to determine the diameter, depth and location of the orSSN; (2) targeting of the orSSN with US in cadaver limbs to determine its distance from the needle, ink marking and locating the orSSN. In Part I, the diameter of the orSSN averaged 1.33 mm (1-9 mm) and its depth averaged 5.12 mm (2.7-10.6 mm). The orSSN was located in the upper trunk of the BP (53) or its posterior division (7). In Part II, the orSSN was successfully targeted in nine of the 10 specimens by US; the needle/orSSN distance averaged 3.8 mm (0-8 mm). The implanted needle was at the orSSN in two cases, proximal to it in seven and distal to it in one. US is a valid modality for describing and pinpointing the orSSN, irrespective of patient morphology. Clin. Anat. 30:747-752, 2017. © 2017Wiley Periodicals, Inc.

Ultrasound‐guided proximal suprascapular nerve block: A cadaveric study

“…We confirmed these findings; however the mean depth of the SSN (1.5 cm (range, 0.6–2.3 cm)) in our study was approximately double that identified by Faruch et al (). Despite this increased depth, we were able to achieve 100% accuracy of US‐guided ink marking of the proximal SSN, confirming that dynamic analysis of the proximal SSN is accurate and reproducible (Laumonerie et al). The injection needle was consistently located distal to the orSSN in an effort to increase the distance of the anesthetic fluid from the PN while maintaining the utility of the orSSN as an anatomic landmark (Table ).…”

“…We advocate for the use of the orSSN as a landmark for US‐guided regional anesthesia of the supraclavicular portion of the SSN. It is important to note, however, that the injections in the present study were performed by a highly experienced operator (Faruch et al ; Laumonerie et al). Due to this, we recommend that the technique and interpretation of BP anatomy on US be mastered in order to obtain satisfactory results (Schneider‐Kolsky et al ; Chan et al 2011; Lapègue et al 2014; Rothe et al ).…”

“…The development of high‐frequency US probes and high‐definition US machines has had a significant impact on the study of superficial nerves (e.g., median, radial, ulnar, and common peroneal). Multiple authors have previously characterized the superficial course of the SSN (Table ) (Schneider‐Kolsky et al ; Chan et al 2011; Rothe et al ; Laumonerie et al ). We confirmed these findings; however the mean depth of the SSN (1.5 cm (range, 0.6–2.3 cm)) in our study was approximately double that identified by Faruch et al ().…”

“…Laumonerie et al () recently demonstrated that US guidance was an appropriate modality with which to identify the origin of the proximal SSN (orSSN). Therefore, we speculate that the US‐guided block of the supraclavicular portion of the SSN, also called the “proximal” SSN, may be a good alternative to the distal SSN block presuming the new method is found to be reliable and safe.…”

The Italian master Leonardo da Vinci and his early understanding of the brachial plexus

“…The brachial plexus continues to be of significant clinical interest [8][9][10][11][12][13] and thus our current knowledge of this structure was begun by the works of da Vinci in the fifteenth century. …”