Location of Needle Tips on Plexus Brachialis in Different Supraclavicular Block Techniques: A Cadaver Study.

Objective: The present study was performed on cadavers to evaluate the efficacy of the different supraclavicular block techniques (Vongvises, Dalens, plumb-bob and inter-SCM) by investigating the location of the needle tip on the brachial plexus and to determine the most suitable block techniques according to the site of the surgery.

Methods: The study was performed on one embalmed and nine fresh cadavers. After the dissection, the skin of the cadavers was restored in its original position. Then, they are positioned, and the needle was inserted according to the technique described by the authors in the original articles. The distances between the needle tip and the three trunks were measured, and the location of the needle tip on the brachial plexus was determined.

Results: A significant difference in the proximity of the needle tip to the middle of the middle truncus was noted only in the inter-SCM technique compared with the Dalens technique at both sides (p<0.05).

Conclusion: In our study, the distance between the needle tip and truncus medius was the shortest in the plumb-bob technique at both sides. Both in the plumb-bob and inter-SCM techniques, the distribution of the needle tip over the trunci of the plexus brachialis was homogenous. In Dalens technique, the needle tip reached the truncus superior or between the truncus superior and n. suprascapularis in 95% of the cases. Further, we concluded that moving the insertion point approximately 1 cm caudal and maintaining the anteroposterior needle direction in the Vongvises technique would result in a successful brachial plexus block.