In vivo regeneration of rat sciatic nerve in a double‐halved stitch‐less guide: A pilot‐study

Abstract

It is about 20 years that tubular nerve guides have been introduced into clinical practice as a reliable alternative to autograft, in gaps not-longer-than 20 mm, bringing the advantage of avoiding donor site sacrifice and morbidity. There are limitations in the application of tubular guides. First, tubular structure in itself makes surgical implantation difficult; second, stitch sutures required to secure the guide may represent a site of unfavorable fibroblastic reaction; third, maximum length and diameter of the guide correlate with the occurrence of a poorer central vascularization of regenerated nerve. We report on the in vivo testing of a new concept of nerve-guide (named NeuroBox) which is double-halved, not-degradable, rigid, and does not require any stitch to be held in place, employing acrylate glue instead. Five male Wistar rats had the new guide implanted in a 4-mm sciatic nerve defect; two guides incorporated a surface constituted of microtrenches aligned longitudinally. Further five rats had the 4-mm gap left without repair. Contralateral intact nerves were used as controls. After 2 months, nerve regeneration occurred in all animals treated by the NeuroBox; fine blood vessels were well represented. There was no regeneration in the un-treated animals. Even if the limited number of animals does not allow to draw definitive conclusions, some result can be highlighted: an easy surgical technique was associated with the box-shaped guide and acrylate glue was easily applied; an adequate intraneural vascularization was found concurrently with the regeneration of the nerve and no adverse fibroblastic proliferation was present.

A more detailed mechanism to explain the “bands of Fontana” in peripheral nerves

“…">If there is a single mechanism producing an optical illusion of the bands (namely, the undulating course of the individual nerve fibers), why do the bands vary so much in shape and pattern? If the bands are produced by assembly of individual nerve fibers, why would they be absent in nerves regenerating inside an experimental nerve guide in a rat model9?…”

“…If the bands are produced by assembly of individual nerve fibers, why would they be absent in nerves regenerating inside an experimental nerve guide in a rat model9?…”

Development of a Device-Assisted Nerve-Regeneration Procedure in Disruptive Lesions of the Brachial Plexus

“…This is in accordance with our previous findings in the rat sciatic nerve. 23,24 Also notable is the device ability to limit neuroma formation.…”

“…[15][16][17][18][19][20][21] In 2006, we developed and tested in vivo a new concept of nerve guide which is double-halved and rigid, and does not require the use of any stitch suture, allowing the use of cyanoacrylate glue instead. [22][23][24] In the "NeuroBox" guide (as it is called), the traditional cylindrical design is replaced by a box of two halves into which three main compartments are recognizable: (1) a lodgement for the neural stump (one proximal and one distal), (2) a compartment for the acrylate glue (one proximal and one distal), and (3) a flat "regeneration chamber" where the bunch of fibers of the proximal stump is facilitated to spread on a wider flat surface. The chamber can receive several treatments like micro-and nanocarving of dedicated topography; implantation of molecules; seeding of cells.…”

“…The device was successfully tested in the rat sciatic nerve model. 23,24 Few years later, we devised a wider "NeuroBox" to be applied in disruptive lesions of the BP in accordance with the following rationale. It is well-known that there is a plexiform structure in any human peripheral nerve.…”