title: Electrophysiologic study of influence on C7 innervated muscles after transection of different C7 fascicles.
abstract: An experimental study was conducted to observe the electrophysiologic changes in C7 innervated muscles following transection of different fascicles of C7 nerve root in the brachial plexus with already transected C5 and C6. Twenty-four Sprague-Dawley rats were randomized into groups A, B, and C. C5 and C6 transection, C5, C6, and partial C7 (anteriolateral fascicles of the anterior division) transection, and C5, C6, and C7 transection were done in group A, B, and C, respectively. One month postoperatively, compound muscle action potentials of the latissimus dorsi, triceps, and extensor digitorum communis were recorded. Decreased amplitude and a prolonged latent period were seen in all three muscles of group C. No obvious changes, however, were found in groups A and B. This suggests that when the upper trunk of the brachial plexus is injured, partial transection of C7 does not obviously impair C7 innervated muscle function. Selective ipsilateral C7 transfer is safe for the treatment of upper-trunk avulsion.
authors.affiliation: Department of Hand Surgery, Hua Shan Hospital, Fudan University, Shanghai, P.R. China. xujianguang@hotmail.com
authors.forename: Jian-Guang
authors.initials: JG
authors.lastname: Xu
authors.forename: Yu-Dong
authors.initials: YD
authors.lastname: Gu
authors.forename: Shao-Nan
authors.initials: SN
authors.lastname: Hu
authors.forename: Huan
authors.initials: H
authors.lastname: Wang
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
mesh_terms: D000200:Action Potentials; D000818:Animals; D001917:Brachial Plexus / Q000293:injuries*; D004576:Electromyography; D018482:Muscle, Skeletal / Q000294:innervation*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013126:Spinal Nerve Roots / Q000502:physiology / Q000601:surgery*