Sectional neuroanatomy of the upper limb I: Brachial plexus

This series of three articles is structured to provide anatomically accurat e functional schematics of the motor and sensory innervation of the shoulde r and upper limb. This first paper provides radiographically oriented sagit tal sections through the brachial plexus to assist in directly identifying a plexal lesion. A coronal schematic of the brachial plexus and summary tab le allows prediction of unique patterns of denervation from 19 lesion sites . Correlation between the lesion and the denervation pattern ensures the le sion is, in fact, clinically significant. The next two articles will presen t a color-coded atlas that allows the radiologist to quickly assess pattern s of denervated muscles and thereby indirectly localize the lesion site. Th us, the three articles can be used together to predict the clinical picture for a given nerve lesion or extrapolate lesion location when a constellati on of denervated muscles are seen on an upper Limb magnetic resonance imagi ng or electromyographic study.