Inside-out and Standard Vein Grafts, with or without Muscle Filling, in Peripheral Nerve Repair: A Histomorphometric Study
Domingos D. Roque
Medical School, Discipline of Human Morphophysiology, University of Marilia (UNIMAR), Marilia, R. Hygino Muzy Filho, 17525-902 Marília, SP, Brazil.
Karina T. Pomini
Department of Biological Sciences (Anatomy), Bauru School of Dentistry, University of São Paulo, Al. Dr. Octávio Pinheiro Brisola 9-75, 17012-901 Bauru, SP, Brazil.
Rogério L. Buchaim *
Department of Biological Sciences (Anatomy), Bauru School of Dentistry, University of São Paulo, Al. Dr. Octávio Pinheiro Brisola 9-75, 17012-901 Bauru, SP, Brazil.
Daniela V. Buchaim
Medical School, Discipline of Human Morphophysiology, University of Marilia (UNIMAR), Marilia, R. Hygino Muzy Filho, 17525-902 Marília, SP, Brazil
Jesus C. Andreo
Department of Biological Sciences (Anatomy), Bauru School of Dentistry, University of São Paulo, Al. Dr. Octávio Pinheiro Brisola 9-75, 17012-901 Bauru, SP, Brazil.
José S. Roque
Department of Anatomy, Northern Paraná State University (UENP), Av. Manoel Ribas 215, 86400-970, Jacarezinho, PR, Brazil.
Antonio C. Rodrigues
Department of Biological Sciences (Anatomy), Bauru School of Dentistry, University of São Paulo, Al. Dr. Octávio Pinheiro Brisola 9-75, 17012-901 Bauru, SP, Brazil.
Geraldo M. Rosa Júnior
Department of Health Sciences, University of Sacred Heart, R. Irmã Arminda 10-50, 17011-160 Bauru, SP, Brazil.
Luis Henrique R. Moraes
Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, UNICAMP, Cidade Universitária Zeferino Vaz - Barão Geraldo, 13083-970 Campinas, SP, Brazil.
Fausto Viterbo
São Paulo State University, Julio de Mesquita Filho, UNESP, Via Domingos Sartori, s/n - Distrito de Rubião Junior, 18607-621 Botucatu, SP, Brazil.
*Author to whom correspondence should be addressed.
Abstract
Aim: The aim of this study was to compare two tubulization techniques, inside-out veins and standard veins, both filled with skeletal muscle or not, in sciatic nerve by morphological and histomorphometric study.
Methodology: Seventy Wistar rats were divided in 4 experimental groups (IOVNF - inside-out vein with no filling; IOVSM - inside-out vein filled with skeletal muscle; SVNF - standard vein with no filling; and SVSM - standard vein filled with skeletal muscle) and a control group (Sham). The left external jugular vein was sectioned into about 14 mm segments to be used as autologous vein grafts. A 10 mm gap was then created in the sciatic nerve and the vein graft was inserted into the vein with or without filling of the right caudal tibial muscle. The animals were euthanized 12 weeks after surgery.
Results: Myelinated and unmyelinated nerve fibers were observed in the histological analyses for all groups, as well as neoformation of the perineurium and intraneural organization of fascicles and blood vessels. In the morphometric analysis of the distal stump, regarding the myelin sheath area, all groups had a significant difference. The IOVNF group had the highest means for fiber, axon and myelin sheath areas. The SVSM group had the lowest means in all features measured, except for the axon area (4.95±1.72 graft; 3.71±0.90 distal stump).
Conclusion: These results show that sciatic nerve repair with inside-out veins and no filling (IOVNF) had the best results, in the majority of measured variables, when compared to the other groups.
Keywords: Autologous graft, nerve repair, nerve regeneration, peripheral nerve, sciatic nerve