Treatment of painful peripheral neuromas by vein implantation

Abstract

Firstly, we designed a vein-implantation model using the rat femoral nerve and vein to study the morphometric changes in nerve endings inserted into venous lumina. By 4 weeks, nerve fibers had extended from the nerve stump into the lumen of the vein and along the endothelium of the vein. After 8 weeks, the lengths and number of nerve fibres extending into the vein lumen began to decrease. At 12 weeks, the nerve ending had developed a hemispherical shape. In none of the experiments was a neuroma formed. Secondly, we treated ten neuromas in ten patients by the vein-implantation method. We obtained excellent results in seven patients. Résumé Dans un premier temps nous avons conçu un modèle d'implantation qui utilise le nerf et la veine fémoral du rat pour étudier les changements morphometriques des terminaisons nerveuses insérées dans la lumière veineuse. A 4 semaines, les fibres du nerf s'étaient étendues à partir de l'extrémité nerveuse le long de l'endothélium de la veine. Après 8 semaines, les longueurs et le nombre de fibres nerveuses développées dans la veine ont commencé à diminuer. À 12 semaines, la terminaison nerveuse avait développé une forme hémisphérique. Dans aucun des cas un névrome ne s'est formé. Dans un deuxième temps nous avons traité 10 névromes chez 10 malades par la méthode de la veine-implantation. Nous avons obtenu d'excellents résultats pour 7 malades.

A free vein graft cap influences neuroma formation after nerve transection

“…Transection of a peripheral nerve may result in the formation of a painful neuroma and numerous surgical strategies have been proposed to prevent this occurrence. 3 In particular, previous evidences 12,14,15,20 have been published suggesting that veins could be used to prevent neuroma formation, and it has been demonstrated that burying transected nerve stumps into an adjacent vein left in place was an effective method in preventing neuroma formation.…”

“…The latter, on the inside of the venous conduit the effects of distal and surrounding growth factors and of the dynamic environment are reduced and the regenerative response can be attenuated. 5,15,20 In this view, it is interesting to note that, in the rat, it has been shown that neuroma formation and neuropathic pain can be reduced by inactivation of both NGF 30 and BDNF. 31 It can thus be hypothesized that isolation of the nerve stump from the environment exerts a preventive effect on neuroma formation also by isolating transected axons from the neurotrophins that are produced by the tissues surrounding the injury sites.…”

“…Nerve covering can be obtained either by burying the nerve stump into a nearby anatomic structure or by capping it with either biological or synthetic material. [7][8][9][10][11][12][13][14][15][16][17][18][19] Among the various attempts, burying of the nerve stump into an adjacent vein have been tested both experimentally 12,15,20 and with patients 10,11,13,14,21 with promising results. Vein tissue are used in nerve surgery also in case of nerve defects where free vein grafts can be used as conduits for bridging the gap.…”

“…Vein tissue are used in nerve surgery also in case of nerve defects where free vein grafts can be used as conduits for bridging the gap. [22][23][24] From this experience, we took the idea to further explore vein tissue covering for neuroma prevention in a rat experimental model using a technique which differs from previous published, 12,15,20 because it is based on capping the transected nerve ending with a free vein graft closed with microsurgical sutures, instead of burying the nerve stump into an adjacent vein left in place.…”

Regeneration of baroafferents after implantation into different vessels

“…More recent studies investigated the sprouting of somatic nerve endings after sectioning and implantation into veins ( Low et al, 1999; Kakinoki et al, 2003; Koch et al, 2003a; 2003b ) . They found that neuroma formation of a sectioned nerve in animals is grossly reduced, when the proximal stump is implanted into a vein ( Low et al, 1999; Koch et al, 2003b ) .…”