A double communication branch between musculocutaneous and median nerves: first case report, anatomical study, and comprehensive review of clinical implications.

Background: According to the literature, the brachial plexus presents a high rate of anatomical variations in the human neural system. The musculocutaneous nerve, a vital component of the brachial plexus, exhibits significant anatomical variations that hold clinical relevance across multiple medical disciplines. This case report, with a comprehensive review, explores the different variations in the course, branching patterns, and clinical implications of the musculocutaneous nerve. Understanding these variations is essential for surgeons, radiologists, and clinicians to enhance surgical precision, improve diagnostic accuracy, and reduce the risk of iatrogenic complications.

Case report: During an anatomical dissection we observed a very rare anatomical variation of the musculocutaneous nerve. Based on this discovery, we performed research in the literature with the aim of finding if this variation has been previously described. Firstly, we identified various classifications of anatomical variations of communicating branches between the musculocutaneous and median nerves, and then we observed that these variations corresponded to various rates of frequency. Our finding is a rare undescribed anatomical variant within the variants classified as Type II according to Le Minor, which is observed in 6.8-10.7% of cases.

Conclusions: The peculiar position of anatomical variations and anastomosis has clinical and functional relevance. Healthcare professionals must be aware of these variations to minimize surgical complications, accurately diagnose neurovascular pathologies, and optimize patient management. Further research into the genetic and embryological underpinnings of these variations may provide additional insights into this intriguing aspect of human anatomy.