Nerve regeneration after delayed nerve repair is often unsuccessful. Indeed, the expression of genes associated with regeneration, including neurotrophic and gliotrophic factors, is drastically reduced in the distal s...Nerve regeneration after delayed nerve repair is often unsuccessful. Indeed, the expression of genes associated with regeneration, including neurotrophic and gliotrophic factors, is drastically reduced in the distal stump of chronically transected nerves; moreover, Schwann cells undergo atrophy, losing their ability to sustain regeneration. In the present study, to provide a three-dimensional environment and trophic factors supporting Schwann cell activity and axon re-growth, we combined the use of an effective conduit(a chitosan tube) with a promising intraluminal structure(fresh longitudinal skeletal muscle fibers). This enriched conduit was used to repair a 10-mm rat median nerve gap after 3-month delay and functional and morphometrical analyses were performed 4 months after nerve reconstruction. Our data show that the enriched chitosan conduit is as effective as the hollow chitosan conduit in promoting nerve regeneration,and its efficacy is not statistically different from the autograft, considered the "gold standard" technique for nerve reconstruction. Since hollow tubes not always lead to good results after long defects(> 20 mm), we believe that the conduit enriched with fresh muscle fibers could be a promising strategy to repair longer gaps, as muscle fibers create a favorable three-dimensional environment and release trophic factors. All procedures were approved by the Bioethical Committee of the University of Torino and by the Italian Ministry of Health(approval number: 864/2016/PR) on September 14, 2016.展开更多
Nerve-tissue interactions are critical.Peripheral nerve injuries may involve intraneural and extraneural scar formation and affect nerve gliding planes,sometimes leading to complex clinical presentations.All of these ...Nerve-tissue interactions are critical.Peripheral nerve injuries may involve intraneural and extraneural scar formation and affect nerve gliding planes,sometimes leading to complex clinical presentations.All of these pathological entities involve pain as the main clinical symptom and can be subsumed under the term“painful scar neuropathy”.The authors review the literature on treatment approaches to peripheral nerve scar neuropathy and the outcomes of neurolysis-associated procedures and propose a simple classification and a therapeutic approach to scar neuropathy.The search retrieved twenty-one papers,twenty of which reported pain reduction or resolution with various techniques.There is no consensus on the best therapeutic approach to neuropathic pain due to scar tethering.Most authors report good or excellent results with different techniques,from nerve wrapping with anti-adhesion devices to nerve coverage or wrapping with vascularized tissue.The authors’classification of and therapeutic approach to peripheral nerve scar lesions aims at promoting a logical approach based on the analysis of lesion type(perineural,or endoneural and perineural),pain type(due to traction or external trauma,pain at rest),and number of previous operations.Patients need to be informed that multiple procedures may be required,that outcomes may be partial,and that surgery can potentially worsen preoperative conditions.The review found no evidence for the best therapeutic approach to scar neuropathy,but there is consensus on a multidisciplinary approach.展开更多
基金supported by the European Community’s Seventh Framework Programme(FP7-HEALTH-2011),No.278612(to SG)by Compagnia di San Paolo,No.D86D15000100005InTheCure project(to SR)
文摘Nerve regeneration after delayed nerve repair is often unsuccessful. Indeed, the expression of genes associated with regeneration, including neurotrophic and gliotrophic factors, is drastically reduced in the distal stump of chronically transected nerves; moreover, Schwann cells undergo atrophy, losing their ability to sustain regeneration. In the present study, to provide a three-dimensional environment and trophic factors supporting Schwann cell activity and axon re-growth, we combined the use of an effective conduit(a chitosan tube) with a promising intraluminal structure(fresh longitudinal skeletal muscle fibers). This enriched conduit was used to repair a 10-mm rat median nerve gap after 3-month delay and functional and morphometrical analyses were performed 4 months after nerve reconstruction. Our data show that the enriched chitosan conduit is as effective as the hollow chitosan conduit in promoting nerve regeneration,and its efficacy is not statistically different from the autograft, considered the "gold standard" technique for nerve reconstruction. Since hollow tubes not always lead to good results after long defects(> 20 mm), we believe that the conduit enriched with fresh muscle fibers could be a promising strategy to repair longer gaps, as muscle fibers create a favorable three-dimensional environment and release trophic factors. All procedures were approved by the Bioethical Committee of the University of Torino and by the Italian Ministry of Health(approval number: 864/2016/PR) on September 14, 2016.
文摘Nerve-tissue interactions are critical.Peripheral nerve injuries may involve intraneural and extraneural scar formation and affect nerve gliding planes,sometimes leading to complex clinical presentations.All of these pathological entities involve pain as the main clinical symptom and can be subsumed under the term“painful scar neuropathy”.The authors review the literature on treatment approaches to peripheral nerve scar neuropathy and the outcomes of neurolysis-associated procedures and propose a simple classification and a therapeutic approach to scar neuropathy.The search retrieved twenty-one papers,twenty of which reported pain reduction or resolution with various techniques.There is no consensus on the best therapeutic approach to neuropathic pain due to scar tethering.Most authors report good or excellent results with different techniques,from nerve wrapping with anti-adhesion devices to nerve coverage or wrapping with vascularized tissue.The authors’classification of and therapeutic approach to peripheral nerve scar lesions aims at promoting a logical approach based on the analysis of lesion type(perineural,or endoneural and perineural),pain type(due to traction or external trauma,pain at rest),and number of previous operations.Patients need to be informed that multiple procedures may be required,that outcomes may be partial,and that surgery can potentially worsen preoperative conditions.The review found no evidence for the best therapeutic approach to scar neuropathy,but there is consensus on a multidisciplinary approach.
