High definition ultrasound imaging of the individual elements of the brachial plexus above the clavicle

Abstract

Background and objectivesUltrasonography of the brachial plexus (BP) has been described but there are limited data on visualization of the T1 ventral ramus and the inferior trunk. This prospective observational study aimed to evaluate a high definition ultrasound imaging technique to systematically identify the individual elements of the BP above the clavicle.MethodsFive healthy young volunteers underwent high definition ultrasound imaging of the BP above the clavicle. The ultrasound scan sequence (transverse oblique scan) commenced at the supraclavicular fossa after which the transducer was slowly swept cranially to the upper part of the interscalene groove and then in the reverse direction to the supraclavicular fossa. The unique sonomorphology of the C7 transverse process was used as the key anatomic landmark to identify the individual elements of the BP in the recorded sonograms.ResultsThe neural elements of the BP that were identified in all volunteers included the ventral rami of C5–T1, the three trunks, divisions of the superior trunk, and formation of the inferior trunk (C8–T1). The C6 ventral ramus exhibited echogenic internal septation with a split (bifid) appearance in four of the five volunteers. In three of the four volunteers with a bifid C6 ventral ramus, the C7 ventral ramus was also bifid.ConclusionWe have demonstrated that it is feasible to accurately identify majority of the main components of the BP above the clavicle, including the T1 ventral ramus and the formation of the inferior trunk, using high definition ultrasound imaging.Trial registration numberChiCTR1900021749.

Selective trunk block (SeTB): a simple alternative to hybrid brachial plexus block techniques for proximal humeral fracture surgery during the COVID-19 pandemic

“…SeTB is made possible from being able to accurately identify the individual trunks of the brachial plexus using ultrasound (figure 1C,F). 2 The SeTB is performed as a "two-injection" peri-plexus technique with the first injection targeting the superior (figure 1D) and middle (figure 1E) trunk at the interscalene groove, and the second injection targeting the inferior trunk at the corner pocket of the supraclavicular fossa (figure 1F). We use up to a maximum of 25 mL of a 1:1 mixture of lidocaine 2% with 1:200 000 epinephrine and levobupivacaine 0.5% for the block.…”

The Tissue Plane

“…There have now been several studies examining nerves of the upper and lower extremities and the soft tissues which surround and envelope these nerves [146][147][148][149]. These have given rise to the term 'paraneural sheath' of the sciatic nerve [146] and brachial plexus [149] respectively.…”

Comparison of the ulnar nerve blockade between intertruncal and corner pocket approaches for supraclavicular block: a randomized controlled trial

“…The supraclavicular brachial plexus block (SCB) is widely used for intraoperative anesthesia and postoperative analgesia. The location of the lower trunk deep within the neural cluster, however, has raised concerns of ulnar nerve (UN) sparing when local anesthetic is not appropriately injected [1,2]. Incomplete blockade of the UN may be avoided by using the corner pocket (CP) approach during SCB [3].…”