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Unusual formation of the musculocutaneous and median nerves: a case report refined by intraneural dissection and literature review
, 5, 1, 1, 1
Affiliations- Department of Normal and Clinical Anatomy, Chair of Anatomy and Histology, Medical University of Lodz, Poland
- Department of Neurosurgery, Tulane University School of Medicine, New Orleans, LA, United States
- Department of Neurosurgery and Ochsner Neuroscience Institute, Ochsner Health System, New Orleans, LA, United States
- Department of Anatomical Sciences, St. George’s University, Grenada
- Department of Neurosurgery, Spine and Peripheral Nerve Surgery, Medical University of Lodz, University Hospital WAM-CSW, Lodz, Poland
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Abstract
This report presents a detailed anatomical investigation of an upper limb specimen showing an atypical formation of the musculocutaneous nerve (MCN) and median nerve (MN). The study was refined by intraneural dissection, which supplements earlier descriptions of similar anatomical variations and allows for revision of the accepted classification.
The case described in this report was an incidental finding during routine dissection of a fixed isolated upper limb. Intraneural dissection revealed partial fusion between the MCN and aberrant bundles of the MN. Those aberrant bundles joined the main steam of the MN at the level at which the MCN branched off as an independent nerve. The procedure allowed the aberrant fibres of the MN to be differentiated from the MCN. The presence of separate bundles in a territory corresponding to the MCN was confirmed, although those bundles and the aberrant MN bundles were covered by a common epineurium. The aberrant MN bundles running within the MCN did not contribute to innervation of the forearm muscles. They rejoined the main nerve trunk in the arm.
A comprehensive understanding of the diverse anatomical variations of the upper limb nerves could be crucial for the safety and success of surgical procedures, especially procedures for reconstructing the brachial plexus or its branches.
Abstract
This report presents a detailed anatomical investigation of an upper limb specimen showing an atypical formation of the musculocutaneous nerve (MCN) and median nerve (MN). The study was refined by intraneural dissection, which supplements earlier descriptions of similar anatomical variations and allows for revision of the accepted classification.
The case described in this report was an incidental finding during routine dissection of a fixed isolated upper limb. Intraneural dissection revealed partial fusion between the MCN and aberrant bundles of the MN. Those aberrant bundles joined the main steam of the MN at the level at which the MCN branched off as an independent nerve. The procedure allowed the aberrant fibres of the MN to be differentiated from the MCN. The presence of separate bundles in a territory corresponding to the MCN was confirmed, although those bundles and the aberrant MN bundles were covered by a common epineurium. The aberrant MN bundles running within the MCN did not contribute to innervation of the forearm muscles. They rejoined the main nerve trunk in the arm.
A comprehensive understanding of the diverse anatomical variations of the upper limb nerves could be crucial for the safety and success of surgical procedures, especially procedures for reconstructing the brachial plexus or its branches.
Keywords
anatomical variation, brachial plexus, median nerve, musculocutaneous nerve, peripheral nerves
About this articleTitle
Unusual formation of the musculocutaneous and median nerves: a case report refined by intraneural dissection and literature review
Journal
Issue
Article type
Case report
Pages
1020-1026
Published online
2020-10-12
Page views
6911
Article views/downloads
912
DOI
Pubmed
Bibliographic record
Folia Morphol 2021;80(4):1020-1026.
Keywords
anatomical variation
brachial plexus
median nerve
musculocutaneous nerve
peripheral nerves
Authors
E. Clarke
R. S. Tubbs
M. Radek
R. Haładaj
M. Tomaszewski
G. Wysiadecki
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