Morphological analysis of peripheral nerve regenerated by means of vein grafts filled with fresh skeletal muscle

Clinical data have shown that a vein segment filled with fresh skeletal mus cle can be considered a good autologous grafting conduit for the repair of peripheral nerve lesions. In this study, the long-term morphological organi zation of rat sciatic nerve fibers regenerated along a muscle-vein-combined graft conduit is further analysed by light and electron microscopy. Regene rated nerve fibers were organized into fascicles of various sizes that were clearly delimited by perineuriallike shells made by long and thin cytoplas mic processes of perineurial-like bipolar cells and by densely packed colla gen fibrils. Grafted skeletal muscle fibers were still detectable among ner ve fiber fascicles. However, in spite of the persistence of skeletal muscle along the graft, regenerated nerve fibers showed a good morphological patt ern of regeneration, providing further evidence that the muscle-vein-combin ed grafting technique represents an effective surgical alternative to the c lassical fresh nerve autograft for the repair of peripheral nerve defects.