title: Microanatomy of the Separable Length of the C7.
abstract: OBJECTIVE
  The objective of this study was to provide anatomical data on modified contralateral C7 (cC7) nerve root transfers by dissecting and measuring the separable lengths of the C7 root, trunk, and divisions.
  
  
  METHODS
  Fifteen adult cervicothoracic specimens were dissected and measured using Vernier calipers after exposing the brachial plexus. Measurements included the length of the C7 from the root to the trunk, the lengths of the C7 root-trunk-anterior division (and posterior division). The epineuria at the C7 root-division-cord junctions were opened until the internal nerve bundles fused together and could not be separated by microdissection. The lengths of the C7 root-trunk-anterior (and posterior) division were measured again after microdissection. The lengths of cC7 nerve of 20 patients with bracial plexus avulsion were measured using the former technique.
  
  
  RESULTS
  The length of the C7 root-trunk was 45.87 SD 10.43 mm. Before separation, the lengths of the C7 root-trunk-anterior division and the root-trunk-posterior division were 61.14 SD 13.44 and 54.63 SD 11.35 mm, respectively; after separation, the lengths were 74.67 SD 12.86 and 68.73 SD 11.86 mm, respectively. The prolonged lengths were 13.15 SD 4.26 and 14.21 SD 6.98 mm, respectively. The prolonged lengths were significantly greater (p < 0.05). The prolonged length of C7 nerve clinically was anterior division, 15.30 SD 3.76 mm and posterior division, 11.10 SD 3.01 mm.
  
  
  CONCLUSIONS
  The C7 division lengths can be prolonged by dissecting the epineuria at the division-cord junction of the C7 nerve root.
authors.affiliation: Department of Orthopaedic Trauma and Microsurgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Ben-gang
authors.initials: BG
authors.lastname: Qin
authors.affiliation: Department of Orthopaedic Trauma and Microsurgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Guo
authors.initials: G
authors.lastname: Fu
authors.affiliation: Department of Orthopaedic Trauma and Microsurgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Jian-tao
authors.initials: JT
authors.lastname: Yang
authors.affiliation: Department of Orthopaedic Trauma and Microsurgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Hong-gang
authors.initials: HG
authors.lastname: Wang
authors.affiliation: Department of Orthopaedic Trauma and Microsurgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Qing-tang
authors.initials: QT
authors.lastname: Zhu
authors.affiliation: Department of Orthopaedic Trauma and Microsurgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Xiao-lin
authors.initials: XL
authors.lastname: Liu
authors.affiliation: Department of Orthopaedic Trauma and Microsurgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Jia-kai
authors.initials: JK
authors.lastname: Zhu
authors.affiliation: Department of Orthopaedic Trauma and Microsurgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Li-qiang
authors.initials: LQ
authors.lastname: Gu
mesh_terms: D000293:Adolescent; D000328:Adult; D001917:Brachial Plexus / Q000033:anatomy & histology* / Q000601:surgery; D020516:Brachial Plexus Neuropathies / Q000601:surgery*; D002102:Cadaver; D002574:Cervical Vertebrae / Q000033:anatomy & histology* / Q000294:innervation / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016067:Nerve Transfer / Q000379:methods*; D013126:Spinal Nerve Roots / Q000033:anatomy & histology* / Q000601:surgery; D055815:Young Adult