Anatomorphometry of the brachial plexus under high-definition system: an experimental study in rats

Abstract

Purpose: To study the anatomorphometry of the plexus brachialis (PB) of rats under a high-definition video system. Methods: Ten male Wistar rats discarded from other research that did not interfere in the morphology of the animal, respecting the principle of reduction, were used. All animals were submitted to the same protocol. Initially, the cervical region was shaved. The animals were placed in a dorsal position. A single elbow-to-elbow incision was performed and dissection started at the deltopectoral sulcus. The procedures were performed under a video system. To measure the structures, the Image J software was used. Results: All the PB evaluated originated from the C5-T1 spinal nerves. C5 and C6 converged to form the truncus superior, the root of C7 originated the truncus medius, and the confluence of C8 and T1 originated the truncus inferior. It was found the union of C7, C8, and T1 to form truncus inferomedialis instead of separate medial and inferior truncus. C8 (1.31 mm) was the thickest root, the truncus inferior (1.80 mm) and the nerve radialis (1.02 mm), were the thickest. Conclusions: The anatomy of the PB is comparable to humans, admitting variations. The videomagnification system is useful to perform microsurgical dissection.

Anatomical description of the ventral and dorsal cervical rootlets in rats: A microsurgical study

“…It is emphasized that this is the first study to quantify the radicular fascicles that forms the ventral and dorsal roots in rats. The videomagnification system used has been shown to offer reliable images with high contrast resolution and improved accuracy to quantify neural anatomy 11 , 18 .…”

“…The procedures were performed under a video system composed by a high-definition Sony camcorder HDR-CX 150 set to 62× magnification, connected with a 4K 55-inch curved television, positioned in front of the surgeon, by a digital HDMI cable 11 . Two white led light sources were used near the camera to provide adequate illumination of the operative field.…”

Anatomical description of the extratemporal facial nerve under high-definition system: a microsurgical study in rats

“…One of the most used models is the rat (Wistar), which has several peculiarities similar to humans, making it one of the main species used in experimental studies on peripheral nerves, mainly due to its anatomical and functional similarity 18,19 .…”

“…Specific studies on the anatomy of the facial nerve of rats are old and lacked the technology to microdissect the terminal branches of the nerve and understand their anatomical distribution 20,21 . For this, the extended video microsurgery system was used, which allows greater comfort for the surgeon and better access to the surgical field, making dissection less time-consuming 19 .…”

“…In the field of experimentation, the rat stands out as an important model used in studies involving nerves due to its easy acquisition and handling, not requiring large physical spaces, and few complications secondary to the surgical procedure are reported. It is also noteworthy that this model has great anatomical similarities with humans, allowing various comparisons 17,18 , such as the techniques of end-to-end neurorrhaphy in cases of neural gaps or performing autografts 19 .…”