Left intercostobrachial nerve variation with dual communications: a cadaveric case report

Area of Science:

• Anatomy
• Surgical Anatomy
• Neuroanatomy

Background:

• The intercostobrachial nerve (ICBN) typically provides sensory innervation to the axilla and upper arm.
• Anatomical variations in the ICBN can affect surgical outcomes and diagnostic procedures.
• Understanding these variations is crucial for accurate clinical practice.

Purpose of the Study:

• To document a rare anatomical variation of the left ICBN.
• To analyze the dual communications between the ICBN, third intercostal nerve, and medial brachial cutaneous nerve (MBCN).
• To discuss the clinical and anatomical significance of this variation.

Main Methods:

• Dissection of the left thoracic wall and axillary region of an adult Chinese male cadaver.
• Detailed observation of the ICBN's origin, course, branches, and communications.
• Precise measurement of nerve distances using a digital caliper.

Main Results:

• The left ICBN originated from the second intercostal nerve and communicated with the third intercostal nerve.
• Dual communications were observed between the ICBN and the medial brachial cutaneous nerve (MBCN).
• Specific distances for these communications were recorded, highlighting the complexity of the nerve network.

Conclusions:

• The ICBN can exhibit complex variations involving T2 and T3 nerve contributions and multiple MBCN communications.
• This anatomical anomaly has significant implications for axillary lymph node dissection, breast surgery, and nerve blocks.
• The ICBN should not be considered a simple, constant sensory branch of T2 during surgical interventions.