Sonographic visualization of the suprascapular canal with focus on the suprascapular notch: anatomical description and ultrasound-probe techniques.

purposeVisualizing the suprascapular notch on radiographic images is challenging. Sonography of the suprascapular notch in the clinical practice had been performed only from a superior shoulder approach projecting a posterior view. Sonographic anterior view of the suprascapular notch has not been presented in the clinical practice. We provide anatomically based ultrasound-probe techniques to capture optimal sonograms exposing the suprascapular canal topography and its key structures.

methodsSonography of the superior shoulder region was bilaterally experimented on ten young healthy (five females and five males) volunteers of age ± 23. We experimented scanning the superior and anterior area of the shoulder at differing angles with ultrasound probe explorative manipulations. Different shoulder maneuvers were attempted in seated and lying positions. Age, sex, BMI, and shoulder thickness were recorded. The visibility of the sonograms was compared based on the obtained parameters. In addition, ultrasound-guided tunnel insertion was performed on a fresh cadaver beside formalin fixed cadaveric dissection for confirmation and illustration of the suprascapular canal anatomy.

resultsA comprehensive protocol was constructed and tested yielding satisfactory sonographic visualization of the suprascapular canal and notch. The sonographic visibility and its quality seemed to be not affected by the BMI directly but primarily by the shoulder thickness with better visibility in females compared to males.

conclusionWe provide a four stepwise shoulder and ultrasound-probe maneuvers protocol yielding an anterior sonographic visibility of the suprascapular notch. This manual provides technical gains in ultrasound-guided clinical practices targeting the suprascapular nerve as it courses through the suprascapular canal.