“Pseudo-suprascapular notch”: is it a sonographic trap in suprascapular nerve block?

Abstract

Background and objectivesThe aim of the study was to describe the radiological anatomy of the pseudo-suprascapular notch—a structure localized at the floor of the supraspinatus fossa, just below the true suprascapular notch. In sonographic examination, it may imitate the suprascapular notch leading to misidentification of these structures.MethodsUltrasound assessment of the suprascapular notch region was performed in 100 patients who underwent chest CT due to other indications. The presence of the suprascapular notch and the pseudo-suprascapular notch was evaluated together with their maximal width and depth using both techniques. The correlation between the dimensions of these two notches was assessed.ResultsThe pseudo-suprascapular notch was recognized in 82 patients. In four of them the suprascapular notch could not be visualized in ultrasound due to obscuring clavicle. In all cases the pseudo-suprascapular notch contained a small artery. In comparison to the suprascapular notch, the pseudo-suprascapular notch was significantly narrower and shallower, except for 10 cases with vestigial suprascapular notch where the pseudo-suprascapular notch was the only hollow in this region. The dimensions of both structures did not correlate with each other. Finally, the pseudo-suprascapular notch did not present any significant asymmetry (p=0.1185) or sexual dimorphism (43 women vs 38 men, p=0.2025).ConclusionsThe pseudo-suprascapular notch is a hollow for nutrient vessels that can be mistaken for the regular suprascapular notch in cases of difficult sonographic navigation.

Hemidiaphragmatic paralysis following ultrasound‐guided anterior vs. posterior suprascapular nerve block: a double‐blind, randomised control trial

“…However, the feasibility of the posterior approach is limited by anatomical landmarks that are difficult to visualise as well as the deep location of the suprascapular nerve [13]. The suprascapular notch presents many anatomical variations making its identification with ultrasound sometimes difficult, which may subsequently lead to a failed block [24,44,45].…”

“…However, the feasibility of the posterior approach is limited by anatomical landmarks that are difficult to visualise as well as the deep location of the suprascapular nerve . The suprascapular notch presents many anatomical variations making its identification with ultrasound sometimes difficult, which may subsequently lead to a failed block . Overall, the posterior approach to the suprascapular nerve seems to be reserved for experts, which increases the risk of widening the gulf between regional anaesthesia experts and generalists .…”

Suprascapular notch cross-sectional area by MRI do not yield accuracy in the diagnosis of suprascapular nerve entrapment – counter point of view

“…In fact, this is a common imaging trap as described by Podgórski at al. [5]. In their ultrasound study, they had mentioned capturing a section behind the SSN will yield a pseudo-notch image on ultrasound [5].…”

“…[5]. In their ultrasound study, they had mentioned capturing a section behind the SSN will yield a pseudo-notch image on ultrasound [5]. This imaging technicality concept stands the same in MRI and CT images of the SSC.…”

“…1E ). In fact, this is a common imaging trap, as described by Podgórski et al [ 5 ] in their ultrasound study, in which they explained that capturing a section behind the SSN yields a pseudo-notch image on ultrasound. This imaging concept is the same on MRI and computed tomography of the SSC.…”