title: Double muscle innervation using end-to-side neurorrhaphy in rats.
abstract: OBJECTIVE
  One of the techniques used for treating facial paralysis is double muscle innervation using end-to-end neurorrhaphy with sectioning of healthy nerves. The aim of this study was to evaluate whether double muscle innervation by means of end-to-side neurorrhaphy could occur, with maintenance of muscle innervation.
  
  
  METHODS
  Experimental study developed at the Experimental Research Center, Faculdade de Medicina de Botucatu, Unesp.
  
  
  METHODS
  One hundred rats were allocated to five groups as follows: G1, control group; G2, the peroneal nerve was sectioned; G3, the tibial nerve was transected and the proximal stump was end-to-side sutured to the intact peroneal nerve; G4, 120 days after the G3 surgery, the peroneal nerve was sectioned proximally to the neurorrhaphy; G5, 120 days after the G3 surgery, the peroneal and tibial nerves were sectioned proximally to the neurorrhaphy.
  
  
  RESULTS
  One hundred and fifty days after the surgery, G3 did not show any change in tibial muscle weight or muscle fiber diameter, but the axonal fiber diameter in the peroneal nerve distal to the neurorrhaphy had decreased. Although G4 showed atrophy of the cranial tibial muscle 30 days after sectioning the peroneal nerve, the electrophysiological test results and axonal diameter measurement confirmed that muscle reinnervation had occurred.
  
  
  CONCLUSIONS
  These findings suggest that double muscle innervation did not occur through end-to-side neurorrhaphy; the tibial nerve was not able to maintain muscle innervation after the peroneal nerve had been sectioned, although muscle reinnervation was found to have occurred, 30 days after the peroneal nerve had been sectioned.
authors: Department of Surgery and Orthopedics, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista, São Paulo, Brazil. elistipp@fmb.unesp.br
authors: Elisangela Jeronymo
authors: EJ
authors: Stipp-Brambilla
authors: Fausto
authors: F
authors: Viterbo
authors: Daniel
authors: D
authors: Labbé
authors: José Antonio
authors: JA
authors: Garbino
authors: Maíra Miranda
authors: MM
authors: Bernardelli
mesh_terms: D000818:Animals; D004576:Electromyography; D005158:Facial Paralysis / Q000601:surgery; D008297:Male; D023421:Models, Animal; D009121:Muscle Denervation / Q000009:adverse effects / Q000379:methods*; D009416:Nerve Regeneration; D010543:Peroneal Nerve / Q000601:surgery*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D013536:Suture Techniques; D013979:Tibial Nerve / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome