title: Histopathological basis of Horner's syndrome in obstetric brachial plexus palsy differs from that in adult brachial plexus injury.
abstract: Although Horner's syndrome is usually taken as an absolute indicator of avulsions of the C8 and T1 ventral roots in adult brachial plexus injury, its pathological basis in obstetric brachial plexus palsy (OBPP) is unclear. We therefore examined the morphological mechanism for the presence of Horner's syndrome in brachial plexus injury in infants and adults. Some axons of sympathetic preganglionic neurons in T1 innervate the superior cervical ganglion via the C7 ventral root in infants but not in adults. Therefore, the presence of Horner's syndrome may relate in part to avulsion of the C7 root in OBPP. These findings suggest that Horner's syndrome in OBPP is not necessarily indicative of avulsions of the C8 and T1 roots, as it can occur with avulsion of the C7 root.
authors.affiliation: Department of Orthopaedics, Tong Ji Hospital, Tong Ji University, Shanghai, China.
authors.forename: Yi-Gang
authors.initials: YG
authors.lastname: Huang
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
authors.forename: Yu-Dong
authors.initials: YD
authors.lastname: Gu
authors.forename: Guang-Rong
authors.initials: GR
authors.lastname: Yu
mesh_terms: D000328:Adult; D000367:Age Factors; D020516:Brachial Plexus Neuropathies / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006732:Horner Syndrome / Q000209:etiology* / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism; D010246:Paralysis, Obstetric / Q000150:complications*; D013126:Spinal Nerve Roots / Q000378:metabolism / Q000473:pathology
chemical_list: D052248:Nitric Oxide Synthase Type I