The amnion muscle combined graft (AMCG) conduits: A new alternative in the repair of wide substance loss of peripheral nerves

Abstract

The use of autologous sural nerve grafts is still the current gold standard for the repair of peripheral nerve injuries with wide substance losses, but with a poor rate of functional recovery after repair of mixed and motor nerves, a limited donor nerve supply, and morbidity of donor site. At present, tubulization through the muscle vein combined graft, is a viable alternative to the nerve autografts and certainly is a matter of tissue engineering still open to continuous development, although this technique is currently limited to a critical gap of 3 cm with less favorable results for motor function recovery. In this report, we present a completely new tubulization method, the amnion muscle combined graft (AMCG) technique, that consists in the combination of the human amniotic membrane hollow conduit with autologous skel-etal muscle fragments for repairing the substance loss of peripheral nerves and recover both sensory and motor functions. In a series of five patients with loss of substance of the median nerve ranging 3-5 cm at the wrist, excellent results graded as S4 in two cases, S31 in two cases, and S3 in one case; M4 in four cases and M3 in one case were achieved. No iatrogenic damage due to withdrawal of a healthy nerve from donor site was observed. This technique allows to repair extensive loss of substance up to 5 cm with a good sensory and motor recovery. The AMCG thus may be considered a reasonable alternative to traditional nerve autograft in selected clinical condi-tions. V C ,

Nerve regeneration techniques respecting the special characteristics of the inferior alveolar nerve

“…Muscle tissue and fat tissue repeatedly have been shown to be suitable materials for bridging nerve defects (Lutz et al, 2001;Lutz, 2004;Meek et al, 2004;Yoshitani et al, 2007;Dornseifer et al, 2011;Manoli et al, 2014;Riccio et al, 2014;Tuncel et al, 2015). Although clinical use of both materials is possible, as many donor sites are accessible, our results indicated no statistically significant difference between the measurements directly after nerve dissection and 24 weeks later.…”

“…Muscle tissue graft for nerval reconstruction seems to be a good alternative in terms of healing (Manoli et al, 2014;Riccio et al, 2014). One study investigated accessory nerve repair using skeletal muscle, with similar results (Bertelli and Ghizoni, 2006).…”

Reconstruction of a long defect of the median nerve with a free nerve conduit flap

“…Furthermore, the basal muscle membrane is rich in neurite-promoting factors such as laminin and fibronectin, which support and promote axon regeneration and Schwann cell migration [6]. The success of this combination technique can be attributed to the orientation of the regenerating axon within the biological conduit; however, it is seemingly effective only for nerve defects of 3 cm or less, and is ineffective for larger nerve gaps [6,7]. This approach prevents vein graft collapse and provides guidance [6], unlike muscle alone.…”

“…The vein-muscle combination is currently the treatment of choice, as has been confirmed via experimental and clinical studies [4,5] illustrating the regenerative potential of the vein and the ability of the muscle to pre-vent vein collapse and promote axon reconstruction. The veinmuscle procedure appears to be suitable for sensory nerves with gaps of 3 cm or less, but it is less efficient in the repair of larger nerve gaps [6,7]. Ample evidence supports the advantages of conventional nerve flaps over nerve grafts for bridging large nerve gaps, since nerve flaps possess sufficient blood supply at the time of nerve transfer and are associated with reduced risk of central necrosis, fibrosis, and disordered histological findings.…”

Újabb ismeretek a szövetépítés (tissue engineering) lehetőségeiről a kézsebészetben. Irodalmi áttekintés

“…Az idegvezetők közül elsősorban a kollagén csöveket használták sikeresen a kisebb idegek (ujjidegek) sérülés okozta hiányai esetében [27]. Újabban Riccio és mtsai [28] emberi amnionmembránból, izomrostokkal együtt tenyésztettek ki idegvezetőt, és az 50 mm-t meg nem haladó idegsérülés helyén alkalmazva mind a szenzoros, mind a motoros funkciók sikeres visszatérését figyelték meg 5 betegüknél. Más kutatók az úgynevezett biológiai idegvezetőket használták fel: polivinil-klorid implantátumot a sérülés helyére beültetve, a körülötte kialakuló kötőszövetes csövet fibrinnel töltötték fel, és patkánykísérleteikben 15 mm-es ideghiányt áthidalva értek el jó eredményt [29].…”