The gross anatomy of the extrathoracic course of the intercostobrachial nerve

Abstract

Recent reports emphasize the importance of preserving the intercostobrachial nerve (ICBN) during surgical procedures (i.e., mastectomy, axillary clearance). However, a limited number of scientific reports explore the surgical anatomy of this nerve. We dissected 100 adult human formalin-fixed cadavers (200 axillae). In all the cadavers the ICBN was present with variant contributions from intercostal nerves T1, T2, T3, and T4. The arrangements of the ICBN were typed as I through VIII. The components of Type I (45% or 90 of our specimens) included a branch to the posterior antebrachial cutaneous nerve, a branch to the anterior and lateral parts of the axilla, a branch to the medial side of the arm, and a branch to the medial antebrachial cutaneous nerve. Type II (25%) describes the ICBN arising from T2 and giving off a branch to the brachial plexus. In Type III (10%), lateral cutaneous branches of T2 and T3 fuse as a common trunk and then split immediately after exiting the intercostal space to form an ICBN. In type IV (5%), T2 and T3 join distally to form an ICBN that ends as its terminal branches. Type V (5%): T3 joins T2 from the same intercostal space proximally, with Type VI (3%) showing a very proximal branching of the sensory terminal nerves. Type VII (5%) displayed a contribution from T3 and a branch to the brachial plexus with multiple terminating branches. A contribution from T3 and T4 and a branch to the brachial plexus with multiple branches of termination comprised Type VIII (2%).

Anatomical information for intercostobrachial nerve preservation in axillary lymph node dissection for breast cancer

“…In some conditions, the ICBN combines with the lateral cutaneous branch of the first and/or intercostal nerve (Loukas et al, 2006). Our study found that a single trunk of the ICBN that originated from the second intercostal nerve accounted for 75.6% (118/156) of cases, but in 21.8% of cases, the ICBN originated from the first intercostal nerve, the first and second intercostal nerves, the second and third intercostal nerves, or the first, second, and third intercostal nerves.…”

Morbidade entre a pós-biópsia de linfonodo sentinela e a dissecção axilar no câncer de mama

“…No entanto, 23 pacientes (62,2%) com DA-NS não apresentaram dor e 10 pacientes (27,05%) não apresentaram déficit sensorial. É possível que nestas pacientes a inervação seja mantida devido às variações na anatomia e distribuição do suprimento nervoso da axila e braço 16 . Com a evolução de cirurgias mais radicais para as cirurgias conservadoras, observou-se que dor crônica também ocorre após setorectomia ou quadrantectomia.…”

The intercostobrachial nerve as a sensory donor for hand reinnervation in brachial plexus reconstruction is a feasible technique and may be useful for restoring sensation

“…As our dissection of the ICBN aimed to reproduce the surgical conditions of a transfer to the LCMN, the dissection was not prolonged distally toward the arm and was interrupted when a sufficient length of the ICBN was achieved to reach the LCMN and the proposed technique could be applied. Thus, some of the communication of the ICBN with other nerves of the upper limb were probably not visualized and described, as they were in other studies 11,12,14,30 . Despite the limitations, our study confirmed the anatomical feasibility of a direct coaptation, without interposition grafts and without tension, between the ICBN and the LCMN through dissection of an average extension of 54 ± 10 mm from the origin of donor nerve to the coaptation point to the recipient nerve.…”

“…Loukas et al 11 described that the ICBN is anatomically constant, and Maycock et al 25 reinforced the idea that the ICBN is responsible for the cutaneous innervation of the axilla region and the medial and posterior aspects of the arm. Thus, this nerve has an area of cortical representation closer to the hand area than the SCN and the ICNs 26 .…”

“…The intercostobrachial nerve (ICBN) arises from the second intercostal nerve as its lateral cutaneous branch 6 , and the axilla and posteromedial aspect of the arm has been related as its cutaneous area of innervation 7 . This nerve has been described in anatomical and clinical studies of axillary approaches to metastatic cancer, lymph node clearance, breast cancer and plastic surgery 8,9,10,11,12,13,14 . The use of the ICBN as a donor nerve for brachial plexus injury was once described by Hattori et al 15 , but in association with ICNs and with no anatomical background study.…”