Anatomical variations detected during ultrasound-guided interscalene brachial plexus block and clinical implications

Year 2020, , 141 - 145, 23.10.2020

Alper Kılıcaslan Funda Gok Ismail Hakkı Korucu Asiye Ozkan Resul Yılmaz

https://doi.org/10.5472/marumj.816311

Cited By: 1

Abstract

Objective: Our aim was to evaluate the anatomic variations detected during ultrasound-guided interscalene brachial plexus block
(US-ISB) and present their clinical implications.
Materials and Methods: After the ethical approval for the study was obtained from the local ethics committee, the files and US records
of patients who underwent US-ISB for anesthesia of the shoulder surgery were retrospectively analyzed.
Results: Anatomical variations which were considered to affect the block technique were detected in 13 (11.8%) of 110 patients. C5
cervical root pierced the anterior scalene muscle (ASM) in 4.5%, and ventral rami of C5 and/or C6 were located in ASM in 3.6% of
patients. There was a muscle bridge between C5 to C6 and C5 to C7 roots in 1.8% of the patients. The brachial plexus was located
medial to ASM and missing from interscalene groove in 1.8% of patients. In one case (C5 root was located in ASM), US-ISB resulted
in incomplete brachial plexus anesthesia, and so general anesthesia (GA) was performed.
Conclusion: Some of the brachial plexus variations in the interscalene area may be associated with further needle manipulation/
redirection and block failure. We consider that prospective studies including more populations are needed to elucidate the effects of
these variations on block parameters.

Keywords

Brachial plexus, Interscalene block, Ultrasonography, Variations

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