Anatomical study of the brachial plexus using surface ultrasound

Area of Science:

• Anesthesiology
• Anatomy
• Medical Imaging

Background:

• Brachial plexus regional anesthesia is a common procedure.
• Accurate anatomical knowledge is crucial for successful nerve block placement.
• Individual anatomical variations can increase the risk of complications.

Purpose of the Study:

• To define the anatomy of the brachial plexus relevant to regional anesthesia.
• To identify and quantify individual anatomical variations.
• To evaluate the utility of surface ultrasound in visualizing these structures.

Main Methods:

• Surface ultrasound examinations were performed on twenty healthy volunteers.
• Detailed anatomical structures of the brachial plexus were visualized in the axillary, supraclavicular, and interscalene regions.
• Variations in the location of nerves (median, radial, ulnar) and vessels (arteries, veins) were documented.

Main Results:

• Significant individual variations were observed in the relative positions of the median, radial, and ulnar nerves to the axillary artery.
• Multiple venous structures were frequently identified in the axilla, prone to compression.
• In some cases, neural elements were found inferior to the subclavian artery (supraclavicular region).
• A vein was identified between nerve trunks in the interscalene region in one volunteer.

Conclusions:

• Considerable anatomical variation exists within the brachial plexus, even in a small cohort.
• Surface ultrasound imaging is a valuable tool for identifying these variations.
• Utilizing ultrasound can enhance the success rate of brachial plexus regional anesthesia.
• Ultrasound guidance may decrease the risk of inadvertent intravascular injection during the procedure.