Anatomical Variations in the Formation and Branching Pattern of the Brachial Plexus: A Cadaveric Study.
Keywords:
Brachial plexus, Anatomical variations, Cadaveric study, Musculocutaneous nerve, Median nerve.Abstract
ABSTRACT
Background: Anatomical variations of the brachial plexus are clinically important during upper-limb surgery, regional anaesthesia, and peripheral nerve interventions.
Objective: To evaluate anatomical variations in the formation and branching patterns of the brachial plexus in adult human cadavers.
Materials and Methods: This descriptive observational cadaveric study included 150 brachial plexuses. The roots, trunks, divisions, cords, terminal branches, and communicating nerves were examined through standard anatomical dissection. Variations were recorded and analysed using descriptive statistics.
Results: Anatomical variations were identified in 54 (36.0%) specimens, while 96 (64.0%) demonstrated normal anatomy. The mean age was 48.2 ± 14.6 years. Prefixed and postfixed formations occurred in 10.7% and 2.7%, respectively. Superior trunk and lateral cord variations were observed in 5.3% and 6.7%. Musculocutaneous nerve variations were most frequent (12.0%), followed by median nerve variations (10.7%). Communicating branches were identified in 12.0%, predominantly between the musculocutaneous and median nerves (9.3%).
Conclusion: Anatomical variations of the brachial plexus were common, particularly involving root formation and terminal branching. Awareness of these variations is essential for safe surgical and anaesthetic procedures.
References
REFERENCES
1. Benes M, Kachlik D, Belbl M, Kunc V, Havlikova S, Whitley A, et al. A meta-analysis on the anatomical variability of the brachial plexus: Part I – Roots, trunks, divisions and cords. Ann Anat. 2021;238:151751.
2. Han Y, An M, Zilundu PLM, Zhuang Z, Chen J, Jiang Z, et al. Anatomical variations of the brachial plexus in adult cadavers: a descriptive study and clinical significance. Microsurgery. 2024;44(5):e31182.
3. Pellerin M, Kimball Z, Tubbs RS, Nguyen S, Matusz P, Cohen-Gadol AA, et al. The prefixed and postfixed brachial plexus: a review with surgical implications. Surg Radiol Anat. 2010;32(3):251-60.
4. Guday E, Bekele A, Muche A. Anatomical study of prefixed versus postfixed brachial plexuses in adult human cadaver. ANZ J Surg. 2017;87(5):399-403.
5. Rastogi R, Budhiraja V, Bansal K. Posterior cord of brachial plexus and its branches: anatomical variations and clinical implication. ISRN Anat. 2013;2013:501813.
6. Benes M, Kachlik D, Belbl M, Whitley A, Havlikova S, Kaiser R, et al. A meta-analysis on the anatomical variability of the brachial plexus: Part II – Branching of the supraclavicular part. Ann Anat. 2021;238:151788.
7. Benes M, Kachlik D, Belbl M, Havlikova S, Kunc V, Whitley A, et al. A meta-analysis on the anatomical variability of the brachial plexus: Part III – Branching of the infraclavicular part. Ann Anat. 2022;244:151976.
8. Ballesteros LE, Ramirez LM. Variations of the origin of collateral branches emerging from the posterior aspect of the brachial plexus. J Brachial Plex Peripher Nerve Inj. 2007;2:14.
9. Pandey SK, Shukla VK. Anatomical variations of the cords of brachial plexus and the median nerve. Clin Anat. 2007;20(2):150-6.
10. Aggarwal A, Sahni D, Kaur H, Batra YK, Sondekoppam RV. A rare anatomical variation of the brachial plexus: single cord anomaly. Anesth Analg. 2012;114(2):466-70.
11. Muthoka JM, Sinkeet SR, Shahbal SH, Matakwa LC, Ogeng'o JA. Variations in branching of the posterior cord of brachial plexus in a Kenyan population. J Brachial Plex Peripher Nerve Inj. 2011;6:1.
12. Aggarwal A, Puri N, Aggarwal AK, Harjeet K, Sahni D. Anatomical variation in formation of brachial plexus and its branching. Surg Radiol Anat. 2010;32(9):891-4.
13. Fazan VPS, Amadeu AS, Caleffi AL, Rodrigues Filho OA. Brachial plexus variations in its formation and main branches. Acta Cir Bras. 2003;18(Suppl 5):14-8.
14. Claassen H, Schmitt O, Wree A, Schulze M. Variations in brachial plexus with respect to concomitant accompanying aberrant arm arteries. Ann Anat. 2016;208:40-8.
15. Clarke E, Tubbs RS, Radek M, Haładaj R, Tomaszewski M, Wysiadecki G. Unusual formation of the musculocutaneous and median nerves: a case report refined by intraneural dissection and literature review. Folia Morphol (Warsz). 2021;80(4):1020-6.
16. Di Stefano V, Gagliardo A, Barbone F, Vitale M, Ferri L, Lupica A, et al. Median-to-ulnar nerve communication in carpal tunnel syndrome: an electrophysiological study. Neurol Int. 2021;13(3):304-14.
