Back to 2014 Annual Meeting Program
Anatomic Sites of Origin of the Suprascapular and Lateral Pectoral Nerves within the Brachial Plexus
Howard M. Clarke, MD, PhD, FRCS(C)1, Ehud Arad1, Zhi Li1, Thomas Sitzman1 and Ann MR Agur, BSc(OT), PhD2
1Division of Plastic Surgery, Hospital for Sick Children, Toronto, ON, Canada, 2Division of Anatomy, University of Toronto, Toronto
Background: The suprascapular nerve (SSN) and the lateral pectoral nerve (LPN) are typically described as originating from the upper trunk (UT) and lateral cord (LC) of the brachial plexus (BP), respectively. However, these descriptions are controversial in the literature and are inconsistent with typical surgical findings. The goal of this study is to clarify the anatomical origins of the SSN and LPN from the BP as an aid to surgical exploration. Methods: The SSN and LPN were studied in 100 adult cadaver specimens. Topographic points of origin were described as distance from the bifurcation of the UT or distance from the formation point of the LC. Structures were digitized in 12 specimens and visual anatomical models were reconstructed. Results: The SSN originated from: (1) the posterior division of UT (UTP) in 61 specimens at a point 3.1±3.1 mm (mean±SD) distal to the bifurcation of the UT; (2) the point of UT bifurcation in 29 cases; (3) the UT in 6 cases at a point 3.8±2.0 mm proximal to bifurcation point; and (4) directly from the C5 root in 4 cases. The LPN originated from: (1) the anterior division of UT (UTA) in 88 cases from a point 24.8 ± 9.9 mm proximal to the point of LC formation; (2) from the point of LC formation in 5 cases; (3) from the LC in 4 cases at a point 12.3 ± 5.9 mm distal to the LC formation point; and (4) solely from the anterior division of the middle trunk (MTA) in 3 cases. Eighty-two cases had origins from both the UTA and MTA. Conclusions: The SSN most frequently originates from the UTP, and the LPN from the UTA and the MTA. This information can be used to guide the surgeon in identifying the key landmarks of the supraclavicular BP at surgical exploration.
Back to 2014 Annual Meeting Program