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1.
Hand Surg Rehabil ; 40(2): 139-144, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33309793

RESUMO

The aims of this study were to evaluate the impact of the COVID-19 pandemic on emergency and elective hand surgery in four Italian regions that had either a high (Lombardy and Piemonte) or a low (Sicilia and Puglia) COVID-19 case load to discuss problems and to elaborate strategies to improve treatment pathways. A panel of hand surgeons from these different regions compared and discussed data from the centers they work in. The COVID-19 pandemic had an enormous impact on both elective and emergency surgery in Italy, not only in highly affected regions but also - and paradoxically even at a higher extent - in regions with a low COVID-19 case load. A durable and flexible redesign of hand surgery activities should be promoted, while changing and hopefully increasing human resources and enhancing administrative support. Telematics must also be implemented, especially for delivering rehabilitation therapy.


Assuntos
COVID-19/epidemiologia , Mãos/cirurgia , Procedimentos Ortopédicos/estatística & dados numéricos , Pandemias , Teste para COVID-19/estatística & dados numéricos , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Itália/epidemiologia , Admissão e Escalonamento de Pessoal/organização & administração , Modalidades de Fisioterapia/organização & administração , Modalidades de Fisioterapia/estatística & dados numéricos , Cuidados Pós-Operatórios , Inquéritos e Questionários , Telemedicina/estatística & dados numéricos
3.
Biomed Mater ; 11(4): 045010, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27508969

RESUMO

Chitosan (CS) has been widely used in a variety of biomedical applications, including peripheral nerve repair, due to its excellent biocompatibility, biodegradability, readily availability and antibacterial activity. In this study, CS flat membranes, crosslinked with dibasic sodium phosphate (DSP) alone (CS/DSP) or in association with the γ-glycidoxypropyltrimethoxysilane (CS/GPTMS_DSP), were fabricated with a solvent casting technique. The constituent ratio of crosslinking agents and CS were previously selected to obtain a composite material having both adequate mechanical properties and high biocompatibility. In vitro cytotoxicity tests showed that both CS membranes allowed cell survival and proliferation. Moreover, CS/GPTMS_DSP membranes promoted cell adhesion, induced Schwann cell-like morphology and supported neurite outgrowth from dorsal root ganglia explants. Preliminary in vivo tests carried out on both types of nerve scaffolds (CS/DSP and CS/GPTMS_DSP membranes) demonstrated their potential for: (i) protecting, as a membrane, the site of nerve crush or repair by end-to-end surgery and avoiding post-operative nerve adhesion; (ii) bridging, as a conduit, the two nerve stumps after a severe peripheral nerve lesion with substance loss. A 1 cm gap on rat median nerve was repaired using CS/DSP and CS/GPTMS_DSP conduits to further investigate their ability to induce nerve regeneration in vivo. CS/GPTMS_DSP tubes resulted to be more fragile during suturing and, along a 12 week post-operative lapse of time, they detached from the distal nerve stump. On the contrary CS/DSP conduits promoted nerve fiber regeneration and functional recovery, leading to an outcome comparable to median nerve repaired by autograft.


Assuntos
Materiais Biocompatíveis/farmacologia , Quitosana/química , Regeneração Nervosa/efeitos dos fármacos , Silanos/química , Animais , Adesão Celular , Proliferação de Células , Reagentes de Ligações Cruzadas/química , Feminino , Gânglios Espinais/efeitos dos fármacos , Nervo Mediano/patologia , Microscopia Confocal , Neurilemoma , Ratos , Ratos Wistar , Células de Schwann/citologia , Estresse Mecânico , Alicerces Teciduais
4.
Acta Otorhinolaryngol Ital ; 36(6): 469-478, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28177329

RESUMO

Virtual surgical planning technology in head and neck surgery is witnessing strong growth. In the literature, the validity of the method from the point of view of accuracy and clinical utility has been widely documented, especially for bone modelling. To date, however, with its increased use in head and neck oncology, and consequently the increased need for bone and soft tissue reconstruction, is important to carry out the virtual programme considering not only bone reconstruction but also all aspects related to the reconstruction of soft tissue using composite flaps. We describe our approach to virtual planning in the case of composite flaps. The study reports six consecutive patients with malignant disease requiring mandibular bone and soft tissue reconstruction using fibular osteocutaneous flaps. In all six patients, the resection and reconstruction were planned virtually focusing on the position of cutaneous perforator vessels in order to schedule fibula cutting guides. There were no complications in all six cases. The technique described allowed us to schedule composite fibula flaps in mandibular reconstruction virtually with good accuracy of the position of the bone segment in relation to the cutaneous paddle, important for soft tissue reconstruction. Despite the limited number of cases, the preliminary results of the study suggest that this protocol is useful in virtual programmes using composite flaps in mandibular reconstruction. Further investigations are needed.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Reconstrução Mandibular/métodos , Neoplasias Bucais/cirurgia , Cirurgia Assistida por Computador , Retalhos Cirúrgicos , Adulto , Idoso , Fáscia/transplante , Feminino , Fíbula/transplante , Humanos , Masculino , Pessoa de Meia-Idade
5.
Gene Ther ; 22(11): 901-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25938193

RESUMO

The Neuregulin/ErbB system plays an important role in the peripheral nervous system, under both normal and pathological conditions. We previously demonstrated that expression of soluble ecto-ErbB4, the released extracellular fragment of the ErbB4 receptor, stimulated glial cell migration in vitro. In this study we examined the possibility of manipulating this system in vivo in order to improve injured peripheral nerve regeneration. Transected rat median nerves of adult female Wistar rats were repaired with a 10-mm-long graft made by muscle-in-vein combined nerve guide previously transduced with either the adeno-associated viral (AAV) vector AAV2-LacZ or AAV2-ecto-ErbB4. Autologous nerve grafts were used as control. Both stereological and functional analyses were performed to assess nerve regeneration. Data show that delivery of soluble ecto-ErbB4 by gene transfer in the muscle-in-vein combined nerve guide has a positive effect on fiber maturation, suggesting that it could represent a potential tool for improving peripheral nerve regeneration.


Assuntos
Regeneração Nervosa/fisiologia , Traumatismos dos Nervos Periféricos/terapia , Nervos Periféricos/fisiologia , Receptor ErbB-4/genética , Animais , Axônios/fisiologia , Dependovirus/genética , Feminino , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Fibras Nervosas/fisiologia , Regeneração Nervosa/genética , Procedimentos Neurocirúrgicos/métodos , Traumatismos dos Nervos Periféricos/genética , Traumatismos dos Nervos Periféricos/metabolismo , Estrutura Terciária de Proteína , Ratos , Ratos Wistar , Receptor ErbB-4/biossíntese
6.
Chir Main ; 34(2): 86-90, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25748585

RESUMO

Tendon adhesions in zone IV after proximal phalangeal fractures are common and may lead to loss of range of motion at the proximal interphalangeal joint. The type of fracture, surgical technique and rehabilitation strategy also influence the final functional outcome. Plate fixation is a reliable solution in cases of comminuted phalangeal fracture. This article describes how adhesions between the plate and extensor apparatus in cases of comminuted fractures of the proximal phalanx can be reduced by using an adipofascial flap.


Assuntos
Placas Ósseas , Falanges dos Dedos da Mão/lesões , Fixação Interna de Fraturas , Fraturas Ósseas/cirurgia , Fraturas Cominutivas/cirurgia , Retalhos Cirúrgicos , Aderências Teciduais/prevenção & controle , Tecido Adiposo/transplante , Adulto , Fáscia/transplante , Humanos , Masculino
7.
Eur Arch Otorhinolaryngol ; 272(6): 1491-501, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24816745

RESUMO

At present, mandibular reconstruction with a fibular free flap is the gold standard for functional and esthetic rehabilitation after oncological surgery. The purpose of this study was to describe the computer-assisted mandibular reconstruction procedure adopting the customized solution Synthes ProPlan CMF. The study reports five consecutive patients with benign or malignant disease requiring mandibular reconstruction using a microvascular fibular free flap, pre-operative virtual planning, construction of cutting guides and customized laser pre-bent titanium plates. The surgical technique is discussed in a step-by-step fashion. The average post-operative hospital stay was 18 ± 3 days. Ischemia time was recorded in all five cases, with an average of 75 ± 8 min. No problems were encountered in any surgical step and there were no major complications. Excellent precision of cutting guides and a good fit of pre-bent plates were found on both the mandible and fibula. There was excellent precision in bone to bone contact and position between mandible and fibula graft. Measurement data from the pre-operative and post-operative CT scans were compared. The average difference (Δ) between programed segment lengths and CT control segment lengths was 0.098 ± 0.077 cm. Microsurgical mandibular reconstruction using a virtual surgical planning yields significantly shorter ischemia times and allows more precise osteotomies. The technology is becoming increasingly recognized for its ability to optimize surgical outcomes and minimize operating time. Considering that the extent of resection can be wider than predicted, this results in safer modeling of the fibula only after frozen sections have demonstrated the radicality of resection.


Assuntos
Fíbula/transplante , Retalhos de Tecido Biológico , Neoplasias de Cabeça e Pescoço/cirurgia , Mandíbula , Reconstrução Mandibular , Complicações Pós-Operatórias/diagnóstico , Interface Usuário-Computador , Adulto , Feminino , Humanos , Masculino , Mandíbula/patologia , Mandíbula/cirurgia , Reconstrução Mandibular/efeitos adversos , Reconstrução Mandibular/métodos , Pessoa de Meia-Idade , Osteotomia/métodos , Planejamento de Assistência ao Paciente , Período Pré-Operatório , Tomografia Computadorizada por Raios X , Resultado do Tratamento
8.
Injury ; 45(2): 437-43, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24129326

RESUMO

Traumatic lesions at the elbow involving great loss of substance are uncommon, but represent a significant problem when such cases are referred to a trauma department. Most of these injuries may cause severe final functional impairment, thereby jeopardising future activities, particularly in cases where treatment was delayed or inappropriate. The timing and method of treatment are critical. The trauma may involve soft tissues only, or bone and joint, or several structures at the same time, which results in combined complex tissue defects. Each type of tissue loss should be managed by choosing the most suitable technique from the armamentarium of reconstructive surgery, taking into account different priorities and the optimum timing (immediate or delayed, one- or two-stages). The authors describe a spectrum of indications and techniques that can be useful tools in managing these injuries.


Assuntos
Articulação do Cotovelo/cirurgia , Consolidação da Fratura , Fraturas Expostas/cirurgia , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles/cirurgia , Lesões do Sistema Vascular/cirurgia , Desbridamento , Articulação do Cotovelo/fisiopatologia , Fixadores Externos , Feminino , Fraturas Expostas/diagnóstico por imagem , Fraturas Expostas/fisiopatologia , Humanos , Masculino , Guias de Prática Clínica como Assunto , Radiografia , Lesões dos Tecidos Moles/diagnóstico por imagem , Lesões dos Tecidos Moles/fisiopatologia , Retalhos Cirúrgicos/inervação , Índices de Gravidade do Trauma , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/fisiopatologia , Lesões no Cotovelo
9.
Injury ; 44(3): 340-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23347767

RESUMO

Tendon adhesions or even secondary ruptures causing severe hand functional impairment still represent a frequent complication after repair of flexor tendon injuries. Secondary treatment of these problems includes tenolysis, one or two stages flexor tendons reconstruction by grafts or even the use of tendon prosthesis. The mechanism and severity of injury, the status of the surrounding tissues and injured finger, the presence of associated lesions, the age of the patient, post-operative management, patient motivation and the surgeon's skill, may all have implications in the final outcome of the tendon reconstruction. A correct evaluation of the problem by means of classifications such as the one described by Boyes, may help the surgeon in choosing the appropriate technique.


Assuntos
Traumatismos da Mão/cirurgia , Procedimentos de Cirurgia Plástica , Traumatismos dos Tendões/cirurgia , Aderências Teciduais/cirurgia , Cicatrização , Competência Clínica/normas , Traumatismos da Mão/fisiopatologia , Traumatismos da Mão/reabilitação , Humanos , Motivação , Cooperação do Paciente , Prognóstico , Implantação de Prótese , Estudos Retrospectivos , Ruptura/cirurgia , Técnicas de Sutura , Traumatismos dos Tendões/fisiopatologia , Traumatismos dos Tendões/reabilitação , Índices de Gravidade do Trauma , Resultado do Tratamento
10.
J Orthop Traumatol ; 13(2): 57-62, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21984203

RESUMO

The fingernail has an important role in hand function, facilitating the pinch and increasing the sensitivity of the fingertip. Therefore, immediate and proper strategy in treating fingernail injuries is essential to avoid aesthetic and functional impairment. Nail-bed and fingertip injuries are considered in this review, including subungual hematoma, wounds, simple lacerations of the nail bed and/or matrix, stellate lacerations, avulsion of the nail bed, ungual matrix defect, nail-bed injuries associated with fractures of the distal phalanx, and associated fingertip injuries. All these injuries require careful initial evaluation and adequate treatment, which is often performed under magnification. Delayed and secondary procedures of fingernail sequelae are possible, but final results are often unpredictable.


Assuntos
Amputação Traumática/cirurgia , Traumatismos dos Dedos/cirurgia , Fixação de Fratura/métodos , Fraturas Ósseas/cirurgia , Unhas/lesões , Procedimentos de Cirurgia Plástica/métodos , Doença Aguda , Humanos , Unhas/cirurgia
12.
J Hand Surg Eur Vol ; 35(2): 109-14, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19687081

RESUMO

Documented experience of treatment of digital nerve lesions with the termino-lateral (end-to-side) nerve suture is limited. Our clinical experience of this technique is detailed here alongside a systematic review of the previous literature. We performed, from 2002 to 2008, seven termino-lateral sutures with epineural window opening for digital nerve lesions. Functional outcome was analysed using the two-point discrimination test and the Semmes-Weinstein monofilament test. The results showed a sensory recovery of S3+ in six cases and S3 in one case. The mean distance found in the two-point discrimination test was 12.7 mm (range 8-18 mm). After a review of the literature, we were able to obtain homogeneous data from 17 additional patients operated by termino-lateral coaptation. The overall number of cases included in our review was 24. A sensory recovery was observed in 23 out of 24 patients. The functional results were S0 in one case, S3 in one case, S3+ in twenty cases and S4 in two cases. Excluding the one unfavourable case, the mean distance in the two-point discrimination test was 9.7 mm (range 3-18 mm). It can thus be concluded that the treatment of digital nerve lesions with termino-lateral suture showed encouraging results. Based on the results obtained in this current study we believe that in case of loss of substance, end-to-side nerve coaptation may be an alternative to biological and synthetic tubulisation when a digital nerve reconstruction by means of nerve autograft is declined by the patient.


Assuntos
Dedos/inervação , Dedos/cirurgia , Traumatismos dos Nervos Periféricos , Nervos Periféricos/cirurgia , Técnicas de Sutura , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Regeneração Nervosa
13.
J Hand Surg Eur Vol ; 34(5): 656-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19587073

RESUMO

We used end-to-side nerve coaptation combined with standard end-to-end neurotisations to treat 11 patients who presented with complete (six cases) or incomplete (five cases) traumatic brachial plexus injuries. All patients were available for functional evaluation at a minimum of 2 years postoperatively. In three patients with shoulder abduction recovery, electromyographical studies (EMG) showed a contribution from the end-to-side neurotisation. In the remaining cases end-to-side neurotisations were unsuccessful. Our study did not demonstrate a reliable role for end-to-side nerve suture in brachial plexus surgery. We believe that at present end-to-side suture must not be a substitute for standard reconstructive techniques in brachial plexus surgery. Occasionally termino-lateral nerve sutures may represent a support to standard reconstructive procedures especially in case of severe injuries when few undamaged donor nerves are available.


Assuntos
Plexo Braquial/lesões , Plexo Braquial/cirurgia , Transferência de Nervo , Radiculopatia/cirurgia , Técnicas de Sutura , Adolescente , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Radiculopatia/diagnóstico , Radiculopatia/etiologia , Recuperação de Função Fisiológica , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
14.
Chir Main ; 28(3): 143-5, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19428284

RESUMO

Traumatic nail injuries are often observed in clinical practice. Usually the fingernail can be preserved, cleaned and disinfected in order to use it in the reconstructive procedure. However, in some cases the nail can be avulsed and lost or too damaged to be used. In cases when the nail is not available it should be replaced by a substitute in order to protect nail bed and avoid adherences along the proximal nail bed and the nail fold. Furthermore the substitute serves to protect the tender nail bed from painful stimuli during the healing process. We used, as fingernail substitute, a polypropylene sheet in eight patients with fingernail avulsion or disruption. The polypropylene foil was trimmed reproducing the profile of the avulsed fingernail and thinned at the proximal edge to reduce thickness in order to ease the insertion into the nail fold. A small hole was then created in the center of the foil to allow blood drainage. The substitute was usually removed one month after the application. In our clinical experience we had not complications related to the polypropylene device. The new fingernail had good cosmetic appearance in most cases and all the patients reported a good protection of the fingertip during the healing period. The substitute used in this series is sterile, inexpensive and easily available in emergency and elective operatory theater. This polypropylene foil is flexible and can be shaped and adapted to the nail curvature radius. The substitute used in our clinical series protected the nail bed during healing until the growth of the new fingernail and respected our functional expectations.


Assuntos
Unhas/lesões , Unhas/cirurgia , Próteses e Implantes , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polipropilenos , Procedimentos de Cirurgia Plástica , Adulto Jovem
15.
Chir Main ; 28(4): 265-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19345602

RESUMO

Chondrosarcoma is the most common primary malignant bone tumour of the hand. This aggressive lesion is extremely rare in the distal phalanx and requires differential diagnosis with enchondroma and onycomatrichoma which are specific neoplasms of this phalanx. We report a case of chondrosarcoma arising from left index distal phalanx, which developed over a long period of time with a progressive deformity of the distal phalanx before becoming painful. The patient was investigated with X-ray and MRI scan which demonstrated a locally aggressive lesion. The surgical procedure was discussed with the patient and consisted of a wide resection with distal phalanx amputation; this surgery left an acceptable functional impairment. Recently, the optimal treatment for chondrosarcoma of the finger has been debated in the literature and a more conservative surgical approach has been proposed. Local recurrence and metastasis have been reported in the literature. Thus, after surgical treatment, the patients should be followed with careful postoperative surveillance.


Assuntos
Neoplasias Ósseas , Condrossarcoma , Falanges dos Dedos da Mão , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/cirurgia , Condrossarcoma/diagnóstico , Condrossarcoma/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade
16.
Acta Neurochir Suppl ; 100: 173-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17985570

RESUMO

Over the last five years, we have used the rat forelimb model for investigating neuromuscular recovery after microsurgical nerve reconstruction of median and ulnar nerves by end-to-side neurorrhaphy and muscle-vein-combined tubulization (using both straight and Y-shaped guides). The outcome of nerve repair at different postoperative times was assessed by functional, morphological and biomolecular analysis. Results showed that both end-to-side and tubulization repair of rat median and ulnar nerves led to successful axonal regeneration along the severed nerve trunk as well as to a partial recovery of the lost function as assessed by grasping test. Biomolecular analysis by means of reverse transcription polymerase chain reaction (RT-PCR) demonstrated early overexpression during nerve regeneration of the gliotrophic factor NRG1 and two of its receptors: erbB2 and erbB3. Finally, our experience also suggests that the rat forelimb experimental model is particularly appropriate for the study of microsurgical reconstruction of major mixed nerve trunks. Furthermore, since the forelimb model is less compromising for the animal, it should be preferred to the hindlimb model for many research purposes.


Assuntos
Regeneração Tecidual Guiada , Nervo Mediano/cirurgia , Tecido Nervoso/transplante , Junção Neuromuscular/patologia , Junção Neuromuscular/fisiopatologia , Procedimentos Neurocirúrgicos , Nervo Ulnar/cirurgia , Anastomose Cirúrgica/métodos , Animais , Axônios , Feminino , Membro Anterior/inervação , Glicoproteínas/metabolismo , Nervo Mediano/metabolismo , Microcirurgia , Regeneração Nervosa , Proteínas do Tecido Nervoso/metabolismo , Neuregulina-1 , Junção Neuromuscular/metabolismo , Ratos , Ratos Wistar , Receptor ErbB-2 , Receptor ErbB-3/metabolismo , Recuperação de Função Fisiológica
17.
Microsurgery ; 27(5): 429-38, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17596863

RESUMO

Tissue engineering has recently seen great advancements in many medical fields, including peripheral nerve reconstruction. In the rat median nerve model, we investigated nerve repair by means of bioengineered tissue scaffolds (muscle-vein-combined tubes) focusing on changes in the neuregulin-1/ErbB-receptor system which represents one of the main regulatory systems of axo-glial interaction in peripheral nerves. Repaired nerves were withdrawn at 5, 15, and 30 days postoperative and processed for morphological and retro-transcriptase polymerase chain reaction (RT-PCR) analysis. Results revealed an early and progressive increase in the expression of NRG1alpha isoform only, while the appearance of the beta isoform of NRG1, which is normally present in peripheral nerves, was delayed. In regards to ErbB2 and ErbB3 receptors, their expression increased progressively inside the muscle-vein-combined scaffolds, though with different kinetics. Taken together, these results suggest that variations in neuregulin-1/ErbB system activation play a key role in peripheral nerve regeneration along bioengineered muscle-vein-combined scaffolds. Since similar variations are also detectable in denervated skeletal muscles, it can be hypothesized that the existence of a NRG1's autocrine/paracrine trophic loop shared by both glial and muscle fibers could be responsible for the effectiveness of muscle-vein-combined conduits for repairing nerve defects.


Assuntos
Fibras Musculares Esqueléticas/transplante , Regeneração Nervosa , Proteínas do Tecido Nervoso/fisiologia , Receptor ErbB-2/fisiologia , Receptor ErbB-3/fisiologia , Veias/transplante , Animais , Axônios/fisiologia , Feminino , Glicoproteínas/fisiologia , Imuno-Histoquímica , Microscopia Confocal , Modelos Animais , Fibras Musculares Esqueléticas/ultraestrutura , Neuregulina-1 , Proteínas Oncogênicas/fisiologia , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células de Schwann/metabolismo , Engenharia Tecidual , Veias/ultraestrutura
18.
Microsurgery ; 27(1): 48-55, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17211839

RESUMO

Over the last 10 years, we have investigated a particular type of bioengineered nerve guide, the muscle-vein-combined tube, which is made by filling a vein with skeletal muscle. In our previous studies we have always used fresh skeletal muscle to fill vein conduits. In the present study we compared the use of fresh and predegenerated (freeze-thawed) skeletal muscle for muscle-vein-combined nerve guides. In this study, a 10-mm-long rat median nerve defect was repaired using either type of nerve guide. The samples were analyzed 5 and 30 days after surgery by light and electron microscopy. In addition, reverse transcription polymerase chain reaction (RT-PCR) was carried out to investigate the expression of mRNAs coding for glial markers, as well as glial growth factor (NRG1) and its receptors (erbB2 and erbB3). Results showed differences between the two types of nerve guides at postoperative day 5; however, no difference was detected at day 30 suggesting that both types of tissue-engineered conduit are effective for repairing peripheral nerve defects in this experimental model.


Assuntos
Nervo Mediano/cirurgia , Fibras Musculares Esqueléticas/transplante , Regeneração Nervosa/fisiologia , Engenharia Tecidual/métodos , Veias/transplante , Animais , Eletroforese , Feminino , Humanos , Nervo Mediano/lesões , Microscopia Eletrônica de Transmissão , RNA Mensageiro/análise , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Neuroscience ; 144(3): 985-90, 2007 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-17157991

RESUMO

Multiple nerve repair by means of a Y-shaped nerve guide represents a good model for studying the specificity of peripheral nerve fiber regeneration. Here we have used it for investigating the specificity of axonal regeneration in mixed nerves of the rat forelimb model. The left median and ulnar nerves, in adult female rats, were transected and repaired with a 14-mm Y-shaped conduit. The proximal end of the Y-shaped conduit was sutured to the proximal stump of either the median nerve or the ulnar nerve. Ten months after surgery, rats were tested for functional recovery of each median and ulnar nerve. Quantitative morphology of regenerated myelinated nerve fibers was then carried out by the two-dimensional disector technique. Results showed that partial recovery of both median and ulnar nerve motor function was regained in all experimental groups. Performance in the grasping test was significantly lower when the ulnar nerve was used as the proximal stump. Ulnar test assessment showed no significant difference between the two Y-shaped repair groups. The number of regenerated nerve fibers was significantly higher in the median nerve irrespectively of the donor nerve, maintaining the same proportion of myelinated fibers between the two nerves (about 60% median and 40% ulnar). On the other hand, nerve fiber size and myelin thickness were significantly larger in both distal nerves when the median nerve was used as the proximal donor nerve stump. G-ratio and myelin thickness/axon diameter ratio returned to normal values in all experimental groups. These results demonstrate that combined Y-shaped-tubulization repair of median and ulnar nerves permits the functional recovery of both nerves, independently from the proximal donor nerve employed, and that tissue, and not topographic, specificity guides nerve fiber regeneration in major forelimb mixed nerves of rats.


Assuntos
Membro Anterior/inervação , Membro Anterior/fisiologia , Regeneração Tecidual Guiada/instrumentação , Regeneração Nervosa/fisiologia , Nervos Periféricos/fisiologia , Próteses e Implantes/tendências , Recuperação de Função Fisiológica/fisiologia , Animais , Axônios/fisiologia , Axônios/ultraestrutura , Axotomia , Contagem de Células , Tamanho Celular , Feminino , Regeneração Tecidual Guiada/métodos , Nervo Mediano/anatomia & histologia , Nervo Mediano/fisiologia , Bainha de Mielina/fisiologia , Bainha de Mielina/ultraestrutura , Fibras Nervosas Mielinizadas/fisiologia , Fibras Nervosas Mielinizadas/ultraestrutura , Nervos Periféricos/anatomia & histologia , Ratos , Nervo Ulnar/anatomia & histologia , Nervo Ulnar/fisiologia
20.
Lasers Med Sci ; 19(1): 57-65, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15316855

RESUMO

Previous studies have shown that low-power laser biostimulation (lasertherapy) promotes posttraumatic nerve regeneration. The objective of the present study was to investigate the effects of postoperative lasertherapy on nerve regeneration after end-to-side neurorrhaphy, an innovative technique for peripheral nerve repair. After complete transection, the left median nerve was repaired by end-to-side neurorrhaphy on the ulnar "donor" nerve. The animals were then divided into four groups: one placebo group, and three laser-treated groups that received lasertherapy three times a week for 3 weeks starting from postoperative day 1. Three different types of laser emission were used: continuous (808 nm), pulsed (905 nm), and a combination of the two. Functional testing was carried out every 2 weeks after surgery by means of the grasping test. At the time of withdrawal 16 weeks postoperatively, muscle mass recovery was assessed by weighing the muscles innervated by the median nerve. Finally, the repaired nerves were withdrawn, embedded in resin and analyzed by light and electron microscopy. Results showed that laser biostimulation induces: (1) a statistically significant faster recovery of the lesioned function; (2) a statistically significant faster recovery of muscle mass; (3) a statistically significant faster myelination of the regenerated nerve fibers. From comparison of the three different types of laser emissions, it turned out that the best functional outcome was obtained by means of pulsed-continuous-combined laser biostimulation. Taken together, the results of the present study confirm previous experimental data on the effectiveness of lasertherapy for the promotion of peripheral nerve regeneration and suggest that early postoperative lasertherapy should be considered as a very promising physiotherapeutic tool for rehabilitation after end-to-side neurorrhaphy.


Assuntos
Terapia a Laser , Nervo Mediano/cirurgia , Regeneração Nervosa/efeitos da radiação , Animais , Método Duplo-Cego , Masculino , Cuidados Pós-Operatórios , Ratos , Ratos Wistar
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