title: Brachial plexus variations in human fetuses.
abstract: OBJECTIVE
  We examined the anatomic variations of the brachial plexus (BP) in human fetuses.
  
  
  METHODS
  This study was performed with 200 BPs from spontaneously aborted fetuses without detectable malformations. The plexuses were dissected, and the normal position and/or morphological variations of the BP were determined and photographed.
  
  
  RESULTS
  There were no variations in 93 plexuses, and 107 plexuses were observed to have different variations. Morphological variations were observed more frequently among female fetuses and right sides. The BPs were composed mostly of the C5, C6, C7, and C8 nerves and the T1 nerve (71.5%). A prefixed plexus was observed in 25.5% of cases, and a postfixed plexus was observed in 2.5% of cases. In one case (0.5%), the C4 and T2 nerves joined the formation. The inferior trunk was not formed in 9% of cases. The superior trunk was not formed in 1% of cases. In one plexus, the superior trunk was formed by the ventral rami of the C4 and C5 nerves. In one case, the inferior trunk was formed by the ventral rami of the T1 and T2 nerves. Division variations were observed most frequently. There were also variations in the terminal branches, such as the roots of the median nerve joining in the distal part of the arm (8.5%), the axillary nerve being separate from the posterior division of the superior trunk (2.5%), and a connection existing between the median and musculocutaneous nerves (1%).
  
  
  CONCLUSIONS
  Knowledge of BP variations is important for surgeons who perform surgical procedures in the cervical and axillary regions.
authors.affiliation: Department of Anatomy, Meram Faculty of Medicine, Selçuk University, Konya, Turkey. iiuysal@yahoo.co.uk
authors.forename: Ismihan Ilknur
authors.initials: II
authors.lastname: Uysal
authors.forename: Muzaffer
authors.initials: M
authors.lastname: Seker
authors.forename: Ahmet Kağan
authors.initials: AK
authors.lastname: Karabulut
authors.forename: Mustafa
authors.initials: M
authors.lastname: Büyükmumcu
authors.forename: Taner
authors.initials: T
authors.lastname: Ziylan
mesh_terms: D001365:Axilla / Q000196:embryology / Q000294:innervation / Q000473:pathology; D001917:Brachial Plexus / Q000002:abnormalities* / Q000196:embryology / Q000473:pathology*; D004210:Dissection; D005260:Female; D005333:Fetus / Q000002:abnormalities* / Q000196:embryology / Q000473:pathology*; D005865:Gestational Age; D006801:Humans; D008297:Male; D009333:Neck / Q000196:embryology / Q000294:innervation / Q000473:pathology