Aberrant Cutaneous Nerve Loops in the Axilla

During routine dissection classes, conducted for first year undergraduate medical students, we encountered a rare anatomical variation in relation to the intercostobrachial nerve (ICBN). The ICBN represents the lateral undivided cutaneous branch of second intercostal nerve. In this case, the ICBN formed nerve loops with branches of the lateral cutaneous branch of the third intercostal nerve. These loops eventually gave branches that probably supplied the floor of the axilla and proximal arm. Nowadays, this ICBN is gaining clinical importance during the axillary lymph node dissections and mammary gland surgeries. Damage to the ICBN, may results in the sensory deficits in patients undergoing surgery. In our case report, ICBN was making aberrant nerve loop along with the branches from the third intercostal nerve. Knowledge regarding the origin, formation and route of ICBN is of clinical significance to axillary surgeons, radiologist and anesthesiologists.