Simplifying ultrasound suprascapular notch exploration for regional anesthesia

Area of Science:

• Anatomy
• Regional Anesthesia
• Medical Imaging

Background:

• Ultrasound-guided suprascapular nerve blocks are common.
• Identifying the suprascapular notch via ultrasound presents challenges due to anatomical variations.

Purpose of the Study:

• To characterize the suprascapular notch using combined ultrasound and dry bone anatomy.
• To develop a simplified, ultrasound-based classification system for anesthesiologists.

Main Methods:

• Anatomical study of 71 dry scapulae using Rengachary classification, measuring notch depth and diameter.
• Ultrasound study of 108 volunteers to assess notch shape and dimensions.

Main Results:

• The most common notch types were III (34%), II (31%), and IV (20%).
• No significant association found between notch type and participant demographics.
• Median depth for types II-IV was 5mm; median diameter was 18mm.

Conclusions:

• Suprascapular notch types II-IV are most prevalent, but significant anatomical diversity exists.
• A simplified ultrasound-based classification focusing on notch identifiability is proposed.
• This system aims to aid clinical decisions and enhance consistency in regional anesthesia practices.