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Du J, Chen H, Qing L, Yang X, Jia X. Biomimetic neural scaffolds: a crucial step towards optimal peripheral nerve regeneration. Biomater Sci 2018; 6:1299-1311. [PMID: 29725688 PMCID: PMC5978680 DOI: 10.1039/c8bm00260f] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Peripheral nerve injury is a common disease that affects more than 20 million people in the United States alone and remains a major burden to society. The current gold standard treatment for critical-sized nerve defects is autologous nerve graft transplantation; however, this method is limited in many ways and does not always lead to satisfactory outcomes. The limitations of autografts have prompted investigations into artificial neural scaffolds as replacements, and some neural scaffold devices have progressed to widespread clinical use; scaffold technology overall has yet to be shown to be consistently on a par with or superior to autografts. Recent advances in biomimetic scaffold technologies have opened up many new and exciting opportunities, and novel improvements in material, fabrication technique, scaffold architecture, and lumen surface modifications that better reflect biological anatomy and physiology have independently been shown to benefit overall nerve regeneration. Furthermore, biomimetic features of neural scaffolds have also been shown to work synergistically with other nerve regeneration therapy strategies such as growth factor supplementation, stem cell transplantation, and cell surface glycoengineering. This review summarizes the current state of neural scaffolds, highlights major advances in biomimetic technologies, and discusses future opportunities in the field of peripheral nerve regeneration.
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Affiliation(s)
- Jian Du
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA. ; Tel: +1 410-706-5025
| | - Huanwen Chen
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA. ; Tel: +1 410-706-5025
| | - Liming Qing
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA. ; Tel: +1 410-706-5025
| | - Xiuli Yang
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA. ; Tel: +1 410-706-5025
| | - Xiaofeng Jia
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA. ; Tel: +1 410-706-5025
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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53
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Casal D, Mota-Silva E, Iria I, Alves S, Farinho A, Pen C, Lourenço-Silva N, Mascarenhas-Lemos L, Silva-Ferreira J, Ferraz-Oliveira M, Vassilenko V, Videira PA, Goyri-O’Neill J, Pais D. Reconstruction of a 10-mm-long median nerve gap in an ischemic environment using autologous conduits with different patterns of blood supply: A comparative study in the rat. PLoS One 2018; 13:e0195692. [PMID: 29659600 PMCID: PMC5902043 DOI: 10.1371/journal.pone.0195692] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Accepted: 03/27/2018] [Indexed: 12/19/2022] Open
Abstract
The aim of this study was to evaluate in the Wistar rat the efficacy of various autologous nerve conduits with various forms of blood supply in reconstructing a 10-mm-long gap in the median nerve (MN) under conditions of local ischemia. A 10-mm-long median nerve defect was created in the right arm. A loose silicone tube was placed around the nerve gap zone, in order to simulate a local ischemic environment. Rats were divided in the following experimental groups (each with 20 rats): the nerve Graft (NG) group, in which the excised MN segment was reattached; the conventional nerve flap (CNF) and the arterialized neurovenous flap (ANVF) groups in which the gap was bridged with homonymous median nerve flaps; the prefabricated nerve flap (PNF) group in which the gap was reconstructed with a fabricated flap created by leaving an arteriovenous fistula in contact with the sciatic nerve for 5 weeks; and the two control groups, Sham and Excision groups. In the latter group, the proximal stump of the MN nerve was ligated and no repair was performed. The rats were followed for 100 days. During this time, they did physiotherapy. Functional, electroneuromyographic and histological studies were performed. The CNF and ANVF groups presented better results than the NG group in the following assessments: grasping test, nociception, motor stimulation threshold, muscle weight, and histomorphometric evaluation. Radial deviation of the operated forepaw was more common in rats that presented worse results in the other outcome variables. Overall, CNFs and ANVFs produced a faster and more complete recovery than NGs in the reconstruction of a 10-mm-long median nerve gap in an ischemic environment in the Wistar rat. Although, results obtained with CNFs were in most cases were better than ANVFs, these differences were not statistically significant for most of the outcome variables.
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Affiliation(s)
- Diogo Casal
- Anatomy Department, NOVA Medical School, Universidade NOVA de Lisboa, Lisbon, Portugal
- Plastic and Reconstructive Surgery Department and Burn Unit, Centro Hospitalar de Lisboa Central–Hospital de São José, Lisbon, Portugal
- UCIBIO, Life Sciences Department, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
- CEDOC, NOVA Medical School, Universidade NOVA de Lisboa, Lisbon, Portugal
| | - Eduarda Mota-Silva
- LIBPhys, Physics Department, Faculdade de Ciências e Tecnologias, Universidade NOVA de Lisboa, Lisbon, Portugal
| | - Inês Iria
- CEDOC, NOVA Medical School, Universidade NOVA de Lisboa, Lisbon, Portugal
| | - Sara Alves
- Pathology Department, Centro Hospitalar de Lisboa Central–Hospital de São José, Lisbon, Portugal
| | - Ana Farinho
- CEDOC, NOVA Medical School, Universidade NOVA de Lisboa, Lisbon, Portugal
| | - Cláudia Pen
- Pathology Department, Centro Hospitalar de Lisboa Central–Hospital de São José, Lisbon, Portugal
| | | | - Luís Mascarenhas-Lemos
- Anatomy Department, NOVA Medical School, Universidade NOVA de Lisboa, Lisbon, Portugal
- Pathology Department, Centro Hospitalar de Lisboa Central–Hospital de São José, Lisbon, Portugal
| | - José Silva-Ferreira
- Pathology Department, Centro Hospitalar de Lisboa Central–Hospital de São José, Lisbon, Portugal
| | - Mário Ferraz-Oliveira
- Pathology Department, Centro Hospitalar de Lisboa Central–Hospital de São José, Lisbon, Portugal
| | - Valentina Vassilenko
- LIBPhys, Physics Department, Faculdade de Ciências e Tecnologias, Universidade NOVA de Lisboa, Lisbon, Portugal
| | - Paula Alexandra Videira
- UCIBIO, Life Sciences Department, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
- CEDOC, NOVA Medical School, Universidade NOVA de Lisboa, Lisbon, Portugal
| | - João Goyri-O’Neill
- Anatomy Department, NOVA Medical School, Universidade NOVA de Lisboa, Lisbon, Portugal
| | - Diogo Pais
- Anatomy Department, NOVA Medical School, Universidade NOVA de Lisboa, Lisbon, Portugal
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D’Arpa S, Zabbia G, Cannizzaro C, Salimbeni G, Plescia F, Mariolo AV, Cassata G, Cicero L, Puleio R, Martorana A, Moschella F, Cordova A. Seeding nerve sutures with minced nerve-graft (MINE-G): a simple method to improve nerve regeneration in rats. Acta Chir Belg 2018; 118:27-35. [PMID: 28738725 DOI: 10.1080/00015458.2017.1353237] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The aim of this study was to assess the effect of seeding the distal nerve suture with nerve fragments in rats. METHODS On 20 rats, a 15 mm sciatic nerve defect was reconstructed with a nerve autograft. In the Study Group (10 rats), a minced 1 mm nerve segment was seeded around the nerve suture. In the Control Group (10 rats), a nerve graft alone was used. At 4 and 12 weeks, a walking track analysis with open field test (WTA), hystomorphometry (number of myelinated fibers (n), fiber density (FD) and fiber area (FA) and soleus and gastrocnemius muscle weight ratios (MWR) were evaluated. The Student t-test was used for statistical analysis. RESULTS At 4 and 12 weeks the Study Group had a significantly higher n and FD (p = .043 and .033). The SMWR was significantly higher in the Study Group at 12 weeks (p = .0207). CONCLUSIONS Seeding the distal nerve suture with nerve fragments increases the number of myelinated fibers, the FD and the SMWR. The technique seems promising and deserves further investigation to clarify the mechanisms involved and its functional effects.
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Affiliation(s)
- Salvatore D’Arpa
- Plastische Heelkunde, Universitair Ziekenhuis Gent, Gent, Belgium
| | - Giovanni Zabbia
- Division of Plastic and Reconstructive Surgery, Department of Surgical, Oncological and Oral Sciences, University of Palermo, Palermo, Italy
| | - Carla Cannizzaro
- Department of Sciences for Health Promotion and Mother and Child Care ‘GIUSEPPE D’ALESSANDRO’, University of Palermo, Palermo, Italy
| | | | - Fulvio Plescia
- Department of Sciences for Health Promotion and Mother and Child Care ‘GIUSEPPE D’ALESSANDRO’, University of Palermo, Palermo, Italy
| | - Alessio Vincenzo Mariolo
- Division of Plastic and Reconstructive Surgery, Department of Surgical, Oncological and Oral Sciences, University of Palermo, Palermo, Italy
| | - Giovanni Cassata
- Laboratory Animal House/Unit, Institute of Experimental Zooprophylactic of Sicily, Palermo, Italy
| | - Luca Cicero
- Laboratory Animal House/Unit, Institute of Experimental Zooprophylactic of Sicily, Palermo, Italy
| | - Roberto Puleio
- Histopathology and Immunohistochemistry Laboratory, Institute Experimental Zooprophylactic of Sicily, Palermo, Italy
| | - Anna Martorana
- Department of Human Pathology, University of Palermo, Palermo, Italy
| | - Francesco Moschella
- Division of Plastic and Reconstructive Surgery, Department of Surgical, Oncological and Oral Sciences, University of Palermo, Palermo, Italy
| | - Adriana Cordova
- Division of Plastic and Reconstructive Surgery, Department of Surgical, Oncological and Oral Sciences, University of Palermo, Palermo, Italy
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Kim JP, Hundepool CA, Friedrich PF, Moran SL, Bishop AT, Shin AY. The effect of full dose composite tissue allotransplantation immunosuppression on allograft motor nerve regeneration in a rat sciatic nerve model. Microsurgery 2017; 38:66-75. [PMID: 28792625 DOI: 10.1002/micr.30211] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 06/01/2017] [Accepted: 07/21/2017] [Indexed: 01/02/2023]
Abstract
BACKGROUND The purpose of this study was to identify which triple immunosuppressive protocols, currently used for vascularized composite allotransplantation in the clinic, will have the best effect on motor function recovery following nerve allograft reconstruction. METHODS Eighty-eight Lewis rats underwent a 1-cm sciatic nerve allograft transplantation and skin graft from 44 Brown-Norway rats. Group I received 0.9% isotonic saline (control); Group II, 2 mg/kg FK506; Group III, 1 mg/kg FK506 with 15 mg/kg mycophenolate mofetil (MMF); and Group IV, 2 mg/kg FK506 with 30 mg/kg MMF and prednisone. Each group consisted of 11 rats. After 12 weeks, motor function recovery was evaluated with isometric tetanic force, muscle mass, ankle contracture angle, electrophysiology, and nerve histomorphometry. Adequacy of immunosuppression was monitored with the transplanted skin graft. All data are expressed as a percentage of the contralateral side. RESULTS Isometric tetanic force showed significantly better functional recovery in all groups treated with immunosuppression compared to control. Within the immunosuppression groups no significant difference was found: 42.1 ± 6.4% (Group I), 56.1 ± 12.4% (Group II), 58.4 ± 10.7% (Group III), and 61.3 ± 11.2% (Group IV). Group IV was superior to all other groups regarding ankle contracture (P < .05) and electrophysiology (P < .001). Skin graft rejection occurred in 41 and 0% (Groups III and IV, respectively). CONCLUSIONS FK506 significantly enhanced motor recovery after allograft reconstruction. This effect was comparable between combination treatment (low-dose FK506 and MMF) and triple therapy (high-dose FK506 and MMF plus prednisolone). However, triple therapy was more effective in suppressing skin rejection.
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Affiliation(s)
- Jong Pil Kim
- Dankook University College of Medicine, Cheonan, South Korea
| | | | | | - Steven L Moran
- Division of Hand Surgery, Mayo Clinic, Rochester, Minnesota.,Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota
| | - Allen T Bishop
- Microvascular Research Laboratory, Mayo Clinic, Rochester, Minnesota.,Division of Hand Surgery, Mayo Clinic, Rochester, Minnesota.,Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota
| | - Alexander Y Shin
- Microvascular Research Laboratory, Mayo Clinic, Rochester, Minnesota.,Division of Hand Surgery, Mayo Clinic, Rochester, Minnesota.,Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota
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Abstract
Injuries to the peripheral nervous system are major sources of disability and often result in painful neuropathies or the impairment of muscle movement and/or normal sensations. For gaps smaller than 10 mm in rodents, nearly normal functional recovery can be achieved; for longer gaps, however, there are challenges that have remained insurmountable. The current clinical gold standard used to bridge long, nonhealing nerve gaps, the autologous nerve graft (autograft), has several drawbacks. Despite best efforts, engineering an alternative "nerve bridge" for peripheral nerve repair remains elusive; hence, there is a compelling need to design new approaches that match or exceed the performance of autografts across critically sized nerve gaps. Here an immunomodulatory approach to stimulating nerve repair in a nerve-guidance scaffold was used to explore the regenerative effect of reparative monocyte recruitment. Early modulation of the immune environment at the injury site via fractalkine delivery resulted in a dramatic increase in regeneration as evident from histological and electrophysiological analyses. This study suggests that biasing the infiltrating inflammatory/immune cellular milieu after injury toward a proregenerative population creates a permissive environment for repair. This approach is a shift from the current modes of clinical and laboratory methods for nerve repair, which potentially opens an alternative paradigm to stimulate endogenous peripheral nerve repair.
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57
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Boriani F, Fazio N, Fotia C, Savarino L, Nicoli Aldini N, Martini L, Zini N, Bernardini M, Baldini N. A novel technique for decellularization of allogenic nerves and in vivo
study of their use for peripheral nerve reconstruction. J Biomed Mater Res A 2017; 105:2228-2240. [DOI: 10.1002/jbm.a.36090] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/21/2017] [Accepted: 04/13/2017] [Indexed: 12/16/2022]
Affiliation(s)
- F. Boriani
- Laboratory for Orthopaedic Pathophysiology and Regenerative Medicine; Rizzoli Orthopaedic Institute; Bologna Italy
| | - N. Fazio
- Prometeo Laboratory; Rizzoli Orthopaedic Institute; Bologna Italy
| | - C. Fotia
- Laboratory for Orthopaedic Pathophysiology and Regenerative Medicine; Rizzoli Orthopaedic Institute; Bologna Italy
| | - L. Savarino
- Laboratory for Orthopaedic Pathophysiology and Regenerative Medicine; Rizzoli Orthopaedic Institute; Bologna Italy
| | - N. Nicoli Aldini
- Laboratory of Preclinical and Surgical Studies; Rizzoli Orthopaedic Institute; Bologna Italy
| | - L. Martini
- Laboratory of Preclinical and Surgical Studies; Rizzoli Orthopaedic Institute; Bologna Italy
| | - N. Zini
- CNR, National Research Council of Italy, Institute of Molecular Genetics; Bologna Italy
- Laboratory of Musculoskeletal Cell Biology; Rizzoli Orthopaedic Institute; Bologna Italy
| | - M. Bernardini
- Department of Animal Medicine; Production and Health, Padova University; Padua Italy
| | - N. Baldini
- Laboratory for Orthopaedic Pathophysiology and Regenerative Medicine; Rizzoli Orthopaedic Institute; Bologna Italy
- Department of Biomedical and Neuromotor Sciences; University of Bologna; Bologna Italy
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Rbia N, Shin AY. The Role of Nerve Graft Substitutes in Motor and Mixed Motor/Sensory Peripheral Nerve Injuries. J Hand Surg Am 2017; 42:367-377. [PMID: 28473159 DOI: 10.1016/j.jhsa.2017.02.017] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 02/22/2017] [Indexed: 02/02/2023]
Abstract
Alternatives to nerve autograft have been invented and approved for clinical use. The reported outcomes of these alternatives in mixed motor nerve repair in humans are scarce and marked by wide variabilities. The purpose of our Current Concepts review is to provide an evidence-based overview of the effectiveness of nerve conduits and allografts in motor and mixed sensory/motor nerve reconstruction. Nerve graft substitutes have good outcomes in mixed/motor nerves in gaps less than 6 mm and internal diameters between 3 and 7 mm. There is insufficient evidence for their use in larger-gap and -diameter nerves; the evidence remains that major segmental motor or mixed nerve injury is optimally treated with a cabled nerve autograft.
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Affiliation(s)
- Nadia Rbia
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN
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Hundepool CA, Nijhuis THJ, Kotsougiani D, Friedrich PF, Bishop AT, Shin AY. Optimizing decellularization techniques to create a new nerve allograft: an in vitro study using rodent nerve segments. Neurosurg Focus 2017; 42:E4. [DOI: 10.3171/2017.1.focus16462] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
OBJECTIVE
Commercially available processed nerve allografts have been shown to be inferior to autografts in previous animal studies. The authors hypothesized that combining different processing and storage techniques will result in improved nerve ultrastructure preservation, lower immunogenicity, and minimized cellular debris. Different processing protocols were evaluated using chemical detergents, enzymes, and irradiation, with the addition the of enzyme elastase, were used. Additionally, the difference between cold and frozen storage was investigated. The goal of this study was to create an optimized nerve allograft.
METHODS
Fifty rat nerves were decellularized with modifications of previous protocols and the addition of elastase. Subsequently, the nerve segments were stored at either 4°C or −80°C. Both processed and fresh control nerves were analyzed with confocal microscopy using immunohistochemical staining on the basal lamina (laminin γ-1), Schwann cells (S100 protein), and immunogenicity using major histocompatibility complex–I (MHCI) staining. Morphology of the ultrastructure and amount of cellular debris were analyzed on cross-sections of the nerves stained with toluidine blue and H & E, and by using electron microscopy.
RESULTS
Nerve ultrastructure was preserved with all decellularization protocols. Storage at −80°C severely altered nerve ultrastructure after any decellularization method. Elastase was found to significantly reduce the immunogenicity and amount of Schwann cells, while maintaining good structural properties.
CONCLUSIONS
Reduced immunogenicity, diminished cellular debris, and the elimination of Schwann cells was observed when elastase was added to the nerve processing while maintaining ultrastructure. Storage at −80°C after the decellularization process heavily damaged the nerve ultrastructure as compared with cold storage. Further in vivo studies are needed to prove the nerve regenerative capacity of these optimized allografts.
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Affiliation(s)
- Caroline A. Hundepool
- 1Department of Orthopedic Surgery, Microvascular Research Laboratory, Mayo Clinic, Rochester, Minnesota; and
- 2Department of Plastic, Reconstructive and Hand Surgery, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Tim H. J. Nijhuis
- 2Department of Plastic, Reconstructive and Hand Surgery, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Dimitra Kotsougiani
- 1Department of Orthopedic Surgery, Microvascular Research Laboratory, Mayo Clinic, Rochester, Minnesota; and
| | - Patricia F. Friedrich
- 1Department of Orthopedic Surgery, Microvascular Research Laboratory, Mayo Clinic, Rochester, Minnesota; and
| | - Allen T. Bishop
- 1Department of Orthopedic Surgery, Microvascular Research Laboratory, Mayo Clinic, Rochester, Minnesota; and
| | - Alexander Y. Shin
- 1Department of Orthopedic Surgery, Microvascular Research Laboratory, Mayo Clinic, Rochester, Minnesota; and
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Hellenbrand DJ, Kaeppler KE, Ehlers ME, Thompson CD, Zurko JC, Buchholz MM, Springer AR, Thompson DL, Ibrahim RK, Hanna A. Immunohistochemical assessment of rat nerve isografts and immunosuppressed allografts. Neurol Res 2016; 38:1094-1101. [PMID: 27809726 DOI: 10.1080/01616412.2016.1248626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVE Autologous peripheral nerve grafts are commonly used clinically as a treatment for peripheral nerve injuries. However, in research using an autologous graft is not always feasible due to loss of function, which in many cases is assessed to determine the efficacy of the peripheral nerve graft. In addition, using allografts for research require the use of an immunosuppressant, which creates unwanted side effects and another variable within the experiment that can affect regeneration. The objective of this study was to analyze graft rejection in peripheral nerve grafts and the effects of cyclosporine A (CSA) on axonal regeneration. METHODS Peripheral nerve grafts in inbred Lewis rats were compared with Sprague-Dawley (SD) rats to assess graft rejection, CSA side effects, immune responses, and regenerative capability. Macrophages and CD8+ cells were labeled to determine graft rejection, and neurofilaments were labeled to determine axonal regeneration. RESULTS SD rats without CSA had significantly more macrophages and CD8+ cells compared to Lewis autografts, Lewis isografts, and SD allografts treated with CSA. Lewis autografts, Lewis isografts, and SD autografts had significantly more regenerated axons than SD rat allografts. Moreover, allografts in immunosuppressed SD rats had significantly less axons than Lewis rat autograft and isografts. DISCUSSION Autografts have long been the gold standard for treating major nerve injuries and these data suggest that even though CSA is effective at reducing graft rejection, axon regeneration is still superior in autografts versus immunosuppressed allografts.
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Affiliation(s)
- Daniel J Hellenbrand
- a Department of Neurological Surgery , University of Wisconsin , Madison , WI , USA
| | - Katie E Kaeppler
- a Department of Neurological Surgery , University of Wisconsin , Madison , WI , USA
| | - Mark E Ehlers
- a Department of Neurological Surgery , University of Wisconsin , Madison , WI , USA
| | - Colton D Thompson
- a Department of Neurological Surgery , University of Wisconsin , Madison , WI , USA
| | - Joanna C Zurko
- a Department of Neurological Surgery , University of Wisconsin , Madison , WI , USA
| | - Morgan M Buchholz
- a Department of Neurological Surgery , University of Wisconsin , Madison , WI , USA
| | - Alexandra R Springer
- a Department of Neurological Surgery , University of Wisconsin , Madison , WI , USA
| | - Daniel L Thompson
- a Department of Neurological Surgery , University of Wisconsin , Madison , WI , USA
| | - Rami K Ibrahim
- a Department of Neurological Surgery , University of Wisconsin , Madison , WI , USA
| | - Amgad Hanna
- a Department of Neurological Surgery , University of Wisconsin , Madison , WI , USA
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Choi Y, Noh H(M. Peripheral nerve regeneration monitoring using multilayer microchannel scaffolds. Neural Regen Res 2016; 11:422-3. [PMID: 27127479 PMCID: PMC4829005 DOI: 10.4103/1673-5374.179052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Abstract
The reconstruction after peripheral nerve damage, especially for long-segment nerve defects, remains a clinical challenge. Autologous nerve graft transplantation is an efficient method for the repair of peripheral nerve defects, but the involved complications and shortcomings have greatly limited the clinical efficacy of treatments offered to patients with nerve defects. Thus, there is an urgent need to develop new therapeutic strategies and explore alternatives to autologous nerve transplantation in clinical practice, based on the knowledge of the peripheral nerve regeneration mechanism and biological histocompatibility principles. With significant advances in the research and application of nerve conduits, they have been used to repair peripheral nerve injury for several decades. In this paper, the study background of nerve conduits, their applications in clinic, status of conduit material research and construction of tissue-engineered artificial nerves were reviewed.
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Abstract
Multiple treatment options are available for patients who have peripheral nerve injuries with a gap. Decellular nerve allografts are one option and provide an extracellular scaffold for neuronal cells to migrate for axonal regrowth. Immunosuppression is not needed because improved nerve processing technologies have rendered decellular nerve allografts nonimmunogenic. These allografts have also shown promising results in both animal and human studies as an alternative repair option.
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65
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Zheng C, Zhu Q, Liu X, Huang X, He C, Jiang L, Quan D. Improved peripheral nerve regeneration using acellular nerve allografts loaded with platelet-rich plasma. Tissue Eng Part A 2015; 20:3228-40. [PMID: 24901030 DOI: 10.1089/ten.tea.2013.0729] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Acellular nerve allografts (ANAs) behave in a similar manner to autografts in supporting axonal regeneration in the repair of short peripheral nerve defects but fail in larger defects. The objective of this article is to evaluate the effect of ANA supplemented with platelet-rich plasma (PRP) to improve nerve regeneration after surgical repair and to discuss the mechanisms that underlie this approach. Autologous PRP was obtained from rats by double-step centrifugation and was characterized by determining platelet numbers and the release of growth factors. Forty-eight Sprague-Dawley rats were randomly divided into 4 groups (12/group), identified as autograft, ANA, ANA loaded with PRP (ANA+PRP), and ANA loaded with platelet-poor plasma (PPP, ANA+PPP). All grafts were implanted to bridge long-gap (15 mm) sciatic nerve defects. We found that PRP with a high platelet concentration exhibited a sustained release of growth factors. Twelve weeks after surgery, the autograft group displayed the highest level of reinnervation, followed by the ANA+PRP group. The ANA+PRP group showed a better electrophysiology response for amplitude and conduction velocity than the ANA and ANA+PPP groups. Based on histological evaluation, the ANA+PRP and autograft groups had higher numbers of regenerating nerve fibers. Quantitative real-time polymerase chain reaction (qRT-PCR) demonstrated that PRP boosted expression of neurotrophins in the regenerated nerves. Moreover, the ANA+PRP and autograft groups showed excellent physiological outcomes in terms of the prevention of muscle atrophy. In conclusion, ANAs loaded with PRP as tissue-engineered scaffolds can enhance nerve regeneration and functional recovery after the repair of large nerve gaps nearly as well as autografts.
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Affiliation(s)
- Canbin Zheng
- 1 Department of Orthopedic and Microsurgery, The First Affiliated Hospital, Sun Yat-sen University , Guangzhou, China
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66
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Henry M. Management of Iatrogenic Ulnar Nerve Transection. J Hand Microsurg 2015; 7:173-6. [PMID: 26078536 DOI: 10.1007/s12593-014-0141-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 05/29/2014] [Indexed: 10/25/2022] Open
Abstract
A case of iatrogenic ulnar nerve laceration at the elbow is presented. Five subsequent surgeries over the course of the ensuing 20 months were performed to address this complication. The article examines the scientific basis for the various decisions needed to formulate a strategy that effectively addresses the problem. Emphasis is placed on the microsurgery of nerve topics: direct nerve repair, autogenous cable nerve grafting, biodegradable conduits, decellularized nerve allograft, and transfer of the anterior interosseous nerve to the ulnar motor branch. The discussion covers the relationship between choices made at the level of the original injury at the cubital tunnel to the timing and selection of distal reconstructive efforts, with specific attention to the distinction between end-to-end anterior interosseous to ulnar motor branch transfer as opposed to the supercharged end-to-side variation of this procedure.
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Affiliation(s)
- Mark Henry
- Hand and Wrist Center of Houston, 1200 Binz Street, 13th Floor, 77004 Houston, TX USA
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67
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Abstract
This article provides an overview of the management of traumatic peripheral nerve injuries. It examines the basic pathophysiology of peripheral nerve injuries, along with the clinical presentation, diagnostic work-up, and treatment options and outcomes for the various classifications of traumatic peripheral nerve injuries.
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Affiliation(s)
- Matthew T Houdek
- Division of Hand and Microvascular Surgery, Department of Orthopedic Surgery, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA
| | - Alexander Y Shin
- Division of Hand and Microvascular Surgery, Department of Orthopedic Surgery, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA.
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Athymic rat model for studying acellular human allograft. J Neurosci Methods 2015; 249:92-8. [PMID: 25936851 DOI: 10.1016/j.jneumeth.2015.04.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 04/15/2015] [Accepted: 04/23/2015] [Indexed: 11/22/2022]
Abstract
BACKGROUND Although human acellular nerve allograft is a promising nerve repair tool, optimizing graft application and understanding effective graft dimensions has been hampered by lack of an appropriate animal model. Rodent nerve acellular allograft can be tested in the utilitarian rodent nerve repair model, but testing different size options is limited by the size of the rodent donor animal. Human acellular nerve allograft offers the variety of sizes desired for more complete study but poses a high risk of rejection as xenograft tissue in the rodent model. Athymic nude rats are less prone to reject xenograft tissue due to their immunocompromised state and may offer an animal model for testing human acellular allograft. METHODS Fifteen athymic nude and 15 Sprague-Dawley rats underwent unilateral excision and repair of a 10mm tibial nerve segment using 10mm of human acellular nerve graft. Testing at 3 months consisted of muscle force measurements, wet muscle weight, and histological assessment from the middle of the nerve grafts. RESULTS Athymic rats repaired with human acellular xenograft demonstrated higher reinnervated muscle weight Gross inspection of the xenograft in euthymic rats revealed a brown and scarred center and histological inspection demonstrated larger axon diameters, and higher midgraft axon counts in the grafts of athymic rats. COMPARISON WITH EXISTING METHODS The athymic rat has been used in many studies that require an immunocompromised host, including implantation of foreign nervous tissue. Previous attempts at implanting acellular nerve xenograft into immunocompetent rats have yielded suboptimal results when compared to allograft. This study is the first to test acellular human nerve allograft in an athymic rat. CONCLUSION The nerve regeneration was better in human acellular nerve allograft implanted into immunocompromised athymic rats when compared to euthymic rats supporting a potential role of this model in studying acellular human nerve tissue.
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Li XY, Hu HL, Fei JR, Wang X, Wang TB, Zhang PX, Chen H. One-stage human acellular nerve allograft reconstruction for digital nerve defects. Neural Regen Res 2015; 10:95-8. [PMID: 25788927 PMCID: PMC4357125 DOI: 10.4103/1673-5374.150712] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/20/2014] [Indexed: 11/24/2022] Open
Abstract
Human acellular nerve allografts have a wide range of donor origin and can effectively avoid nerve injury in the donor area. Very little is known about one-stage reconstruction of digital nerve defects. The present study observed the feasibility and effectiveness of human acellular nerve allograft in the reconstruction of < 5-cm digital nerve defects within 6 hours after injury. A total of 15 cases of nerve injury, combined with nerve defects in 18 digits from the Department of Emergency were enrolled in this study. After debridement, digital nerves were reconstructed using human acellular nerve allografts. The patients were followed up for 6–24 months after reconstruction. Mackinnon-Dellon static two-point discrimination results showed excellent and good rates of 89%. Semmes-Weinstein monofilament test demonstrated that light touch was normal, with an obvious improvement rate of 78%. These findings confirmed that human acellular nerve allograft for one-stage reconstruction of digital nerve defect after hand injury is feasible, which provides a novel trend for peripheral nerve reconstruction.
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Affiliation(s)
- Xue-Yuan Li
- Department of Hand Surgery, Ningbo No.6 Hospital, Ningbo, Zhejiang Province, China
| | - Hao-Liang Hu
- Department of Hand Surgery, Ningbo No.6 Hospital, Ningbo, Zhejiang Province, China
| | - Jian-Rong Fei
- Department of Hand Surgery, Ningbo No.6 Hospital, Ningbo, Zhejiang Province, China
| | - Xin Wang
- Department of Hand Surgery, Ningbo No.6 Hospital, Ningbo, Zhejiang Province, China
| | - Tian-Bing Wang
- Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China
| | - Pei-Xun Zhang
- Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China
| | - Hong Chen
- Department of Hand Surgery, Ningbo No.6 Hospital, Ningbo, Zhejiang Province, China
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Giusti G, Lee JY, Kremer T, Friedrich P, Bishop AT, Shin AY. The influence of vascularization of transplanted processed allograft nerve on return of motor function in rats. Microsurgery 2014; 36:134-43. [PMID: 25557845 DOI: 10.1002/micr.22371] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 11/28/2014] [Accepted: 12/11/2014] [Indexed: 11/07/2022]
Abstract
Processed nerve allografts have become an alternative to repair segmental nerve defects, with results comparable with autografts regarding sensory recovery; however, they have failed to reproduce comparable motor recovery. The purpose of this study was to determine how revascularizaton of processed nerve allograft would affect motor recovery. Eighty-eight rats were divided in four groups of 22 animals each. A unilateral 10-mm sciatic nerve defect was repaired with allograft (group I), allograft wrapped with silicone conduit (group II), allograft augmented with vascular endothelial growth factor (group III), or autograft (group IV). Eight animals from each group were sacrificed at 3 days, and the remaining animals at 16 weeks. Revascularization was evaluated by measuring the graft capillary density at 3 days and 16 weeks. Measurements of ankle contracture, compound muscle action potential, tibialis anterior muscle weight and force, and nerve histomorphometry were performed at 16 weeks. All results were normalized to the contralateral side. The results of capillary density at 3 days were 0.99% ± 1.3% for group I, 0.33% ± 0.6% for group II, 0.05% ± 0.1% for group III, and 75.6% ± 45.7% for group IV. At 16 weeks, the results were 69.9% ± 22.4% for group I, 37.0% ± 16.6% for group II, 84.6% ± 46.6% for group III, and 108.3% ± 46.8% for group IV. The results of muscle force were 47.5% ± 14.4% for group I, 21.7% ± 13.5% for group II, 47.1% ± 7.9% for group III, and 54.4% ± 10.6% for group IV. The use of vascular endothelial growth factor in the fashion used in this study improved neither the nerve allograft short-term revascularization nor the functional motor recovery after 16 weeks. Blocking allograft vascularization from surrounding tissues was detrimental for motor recovery. The processed nerve allografts used in this study showed similar functional motor recovery compared with that of the autograft.
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Affiliation(s)
| | - Joo-Yup Lee
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN
| | - Thomas Kremer
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN
| | | | - Allen T Bishop
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN.,Microvascular Research Laboratory, Mayo Clinic, Rochester, MN
| | - Alexander Y Shin
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN.,Microvascular Research Laboratory, Mayo Clinic, Rochester, MN
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Peripheral nerve injuries: advancing the field through research, collaboration, and education. J Hand Surg Am 2014; 39:2052-8. [PMID: 25124088 DOI: 10.1016/j.jhsa.2014.06.126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 06/24/2014] [Accepted: 06/24/2014] [Indexed: 02/02/2023]
Abstract
The Andrew J. Weiland Medal is presented each year by the American Society for Surgery of the Hand and the American Foundation for Surgery of the Hand for a body of work related to hand surgery research. This essay, awarded the Weiland Medal in 2013, focuses on advancing the field of peripheral nerve injuries through research, collaboration, and education.
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72
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Giusti G, Shin RH, Lee JY, Mattar TG, Bishop AT, Shin AY. The influence of nerve conduits diameter in motor nerve recovery after segmental nerve repair. Microsurgery 2014; 34:646-52. [DOI: 10.1002/micr.22312] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 08/05/2014] [Accepted: 08/08/2014] [Indexed: 02/06/2023]
Affiliation(s)
| | - Richard H. Shin
- Microvascular Research Laboratory; Mayo Clinic; Rochester MN
| | - Joo-Yup Lee
- Microvascular Research Laboratory; Mayo Clinic; Rochester MN
| | - Tiago G. Mattar
- Microvascular Research Laboratory; Mayo Clinic; Rochester MN
| | - Allen T. Bishop
- Microvascular Research Laboratory; Mayo Clinic; Rochester MN
- Department of Orthopedic Surgery; Mayo Clinic; Rochester MN
| | - Alexander Y. Shin
- Microvascular Research Laboratory; Mayo Clinic; Rochester MN
- Department of Orthopedic Surgery; Mayo Clinic; Rochester MN
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Abstract
Nerve conduits and acellular nerve allograft offer efficient and convenient tools for overcoming unexpected gaps during nerve repair. Both techniques offer guidance for migrating Schwann cells and axonal regeneration though utilizing very different scaffolds. The substantially greater amount of animal and clinical data published on nerve conduits is marked by wide discrepancies in results that may be partly explained by a still poorly defined critical repair gap and diameter size. The available information on acellular allografts appears more consistently positive though this tool is also hampered by a longer but also limited critical length. This article reviews the current relative literature and examines pertinent parameters for application of both acellular allograft and nerve conduits in overcoming short nerve gaps.
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Dayawansa S, Wang EW, Liu W, Markman JD, Gelbard HA, Huang JH. Allotransplanted DRG neurons or Schwann cells affect functional recovery in a rodent model of sciatic nerve injury. Neurol Res 2014; 36:1020-1027. [PMID: 24836462 DOI: 10.1179/1743132814y.0000000386] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
OBJECTIVE In this study, the functional recoveries of Sprague-Dawley rats following repair of a complete sciatic nerve transection using allotransplanted dorsal root ganglion (DRG) neurons or Schwann cells were examined using a number of outcome measures. METHODS Four groups were compared: (1) repair with a nerve guide conduit seeded with allotransplanted Schwann cells harvested from Wistar rats, (2) repair with a nerve guide conduit seeded with DRG neurons, (3) repair with solely a nerve guide conduit, and (4) sham-surgery animals where the sciatic nerve was left intact. The results corroborated our previous reported histology findings and measures of immunogenicity. RESULTS The Wistar-DRG-treated group achieved the best recovery, significantly outperforming both the Wistar-Schwann group and the nerve guide conduit group in the Von Frey assay of touch response (P < 0.05). Additionally, Wistar-DRG and Wistar-Schwann seeded repairs showed lower frequency and severity in an autotomy measure of the self-mutilation of the injured leg because of neuralgia. CONCLUSION These results suggest that in complete peripheral nerve transections, surgical repair using nerve guide conduits with allotransplanted DRG and Schwann cells may improve recovery, especially DRG neurons, which elicit less of an immune response.
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Affiliation(s)
- Samantha Dayawansa
- Department of Neurosurgery, University of Rochester, NY, USA.,Department of Pathology, University of Buffalo, NY, USA
| | - Ernest W Wang
- Department of Neurosurgery, University of Rochester, NY, USA.,Center for Neural Development and Disease, University of Rochester, NY, USA
| | - Weimin Liu
- Department of Neurosurgery, University of Rochester, NY, USA.,Center for Neural Development and Disease, University of Rochester, NY, USA
| | - John D Markman
- Department of Neurosurgery, University of Rochester, NY, USA.,Center for Neural Development and Disease, University of Rochester, NY, USA.,Department of Neurology, University of Rochester, NY, USA
| | - Harris A Gelbard
- Center for Neural Development and Disease, University of Rochester, NY, USA.,Department of Neurology, University of Rochester, NY, USA
| | - Jason H Huang
- Department of Neurosurgery, University of Rochester, NY, USA.,Center for Neural Development and Disease, University of Rochester, NY, USA.,Department of Neurosurgery, Scott & White Health System, Temple, TX, USA
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Abstract
When possible, direct repair remains the current standard of care for the repair of peripheral nerve lacerations. In large nerve gaps, in which direct repair is not possible, grafting remains the most viable option. Nerve scaffolds include autologous conduits, artificial nonbioabsorbable conduits, and bioabsorbable conduits and are options for repair of digital nerve gaps that are <3 cm in length. Experimental studies suggest that the use of allografts may be an option for repairing larger sensory nerve gaps without associated donor-site morbidity.
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Affiliation(s)
- Justin W Griffin
- Department of Orthopaedic Surgery, University of Virginia Health System, 400 Ray C. Hunt Drive, Suite 330, P.O. Box 800159, Charlottesville, VA 22908-0159
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Abstract
Major peripheral nerve injuries in the upper extremities can result in significant morbidity. Understanding the pathophysiology of these injuries aids in the assessment and planning of appropriate treatment. With limited nerve mobilization, tension-free repairs can often be performed using sutures, fibrin glue, or nerve connectors. Acellular allograft and autograft reconstruction are better for bridging any gaps greater than a few millimeters. Adherence to proper principles of nerve repair improves the chances of achieving a favorable result, although in general these injuries portend a guarded prognosis.
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Tang P, Kilic A, Konopka G, Regalbuto R, Akelina Y, Gardner T. Histologic and functional outcomes of nerve defects treated with acellular allograft versus cabled autograft in a rat model. Microsurgery 2013; 33:460-7. [PMID: 23861174 DOI: 10.1002/micr.22102] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2013] [Revised: 02/07/2013] [Accepted: 02/11/2013] [Indexed: 12/22/2022]
Abstract
PURPOSE Acellular nerve allograft is a new option for bridging nerve defects that allows appropriate diameter matching. The aim of the study was to compare the histologic and functional recovery of nerve defects treated with acellular nerve allograft versus cabled sural nerve autograft. METHOD Fifty-four Sprague-Dawley rats were divided into one of three experimental groups. A unilateral 10 mm sciatic nerve defect was created and repaired with an acellular nerve allograft (Group A), three cabled sural nerve autografts in antidromic orientation (Group B), and the newly created segmental defect in antidromic orientation (reversed autograft) (Group C). Two rats in each group we evaluated histologically at 6 weeks while the rest of the groups were tested histologically and functionally at 12 weeks. RESULTS There were no differences in histomorphometry between the groups at 6 weeks, but at 12 weeks at mid-graft there were differences. Group C had the highest fiber count which was statistically greater when compared to Group A (P = 0.023) and when compared to Group B (P = 0.001). The average normalized maximum isometric tetanic force (ITF) was 52 ± 2.9% for Group A, 34.1 ± 4.2% for Group B, and 51.3 ± 3.3% for Group C at 12 weeks. There was no statistical difference between Groups A and C, but Group A was statistically greater when compared to B, and when Group C was compared to B. CONCLUSION In conclusion, acellular nerve allograft demonstrated equal functional recovery when compared to reversed autograft (control), and superior recovery compared to the cabled nerve autograft.
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Affiliation(s)
- Peter Tang
- Department of Orthopaedic Surgery, Allegheny Health System, Pittsburgh, PA, USA.
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Jin J, Limburg S, Joshi SK, Landman R, Park M, Zhang Q, Kim HT, Kuo AC. Peripheral nerve repair in rats using composite hydrogel-filled aligned nanofiber conduits with incorporated nerve growth factor. Tissue Eng Part A 2013; 19:2138-46. [PMID: 23659607 DOI: 10.1089/ten.tea.2012.0575] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Repair of peripheral nerve defects with current synthetic, tubular nerve conduits generally shows inferior recovery when compared with using nerve autografts, the current gold standard. We tested the ability of composite collagen and hyaluronan hydrogels, with and without the nerve growth factor (NGF), to stimulate neurite extension on a promising aligned, nanofiber poly-L-lactide-co-caprolactone (PLCL) scaffold. In vitro, the hydrogels significantly increased neurite extension from dorsal root ganglia explants. Consistent with these results, the addition of hydrogels as luminal fillers within aligned, nanofiber tubular PLCL conduits led to improved sensory function compared to autograft repair in a critical-size defect in the sciatic nerve in a rat model. Sensory recovery was assessed 3 and 12 weeks after repair using a withdrawal assay from thermal stimulation. The addition of hydrogel did not enhance recovery of motor function in the rat model. The NGF led to dose-dependent improvements in neurite out-growth in vitro, but did not have a significant effect in vivo. In summary, composite collagen/hyaluronan hydrogels enhanced sensory neurite outgrowth in vitro and sensory recovery in vivo. The use of such hydrogels as luminal fillers for tubular nerve conduits may therefore be useful in assisting restoration of protective sensation following peripheral nerve injury.
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Affiliation(s)
- Jenny Jin
- Department of Orthopaedic Surgery, University of California-San Francisco, CA 94121, USA
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Strauch RJ, Strauch B. Nerve conduits: an update on tubular nerve repair and reconstruction. J Hand Surg Am 2013; 38:1252-5; quiz 1255. [PMID: 23602436 DOI: 10.1016/j.jhsa.2013.02.034] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 02/05/2013] [Accepted: 02/18/2013] [Indexed: 02/02/2023]
Affiliation(s)
- Robert J Strauch
- Department of Orthopaedic Surgery, Columbia University, New York, NY 10032, USA.
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81
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Abou Neel EA, Bozec L, Knowles JC, Syed O, Mudera V, Day R, Hyun JK. Collagen--emerging collagen based therapies hit the patient. Adv Drug Deliv Rev 2013; 65:429-56. [PMID: 22960357 DOI: 10.1016/j.addr.2012.08.010] [Citation(s) in RCA: 190] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2012] [Revised: 08/10/2012] [Accepted: 08/28/2012] [Indexed: 12/11/2022]
Abstract
The choice of biomaterials available for regenerative medicine continues to grow rapidly, with new materials often claiming advantages over the short-comings of those already in existence. Going back to nature, collagen is one of the most abundant proteins in mammals and its role is essential to our way of life. It can therefore be obtained from many sources including porcine, bovine, equine or human and offer a great promise as a biomimetic scaffold for regenerative medicine. Using naturally derived collagen, extracellular matrices (ECMs), as surgical materials have become established practice for a number of years. For clinical use the goal has been to preserve as much of the composition and structure of the ECM as possible without adverse effects to the recipient. This review will therefore cover in-depth both naturally and synthetically produced collagen matrices. Furthermore the production of more sophisticated three dimensional collagen scaffolds that provide cues at nano-, micro- and meso-scale for molecules, cells, proteins and bulk fluids by inducing fibrils alignments, embossing and layered configuration through the application of plastic compression technology will be discussed in details. This review will also shed light on both naturally and synthetically derived collagen products that have been available in the market for several purposes including neural repair, as cosmetic for the treatment of dermatologic defects, haemostatic agents, mucosal wound dressing and guided bone regeneration membrane. There are other several potential applications of collagen still under investigations and they are also covered in this review.
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Abstract
Since the advent of the operating microscope by Julius Jacobson in 1960, reconstructive microsurgery has become an integral part of extremity reconstruction and orthopaedics. During World War I, with the influx of severe extremity trauma Harold Gillies introduced the concept of the reconstructive ladder for wound closure. The concept of the reconstructive ladder goes from simple to complex means of attaining wound closure. Over the last half century microsurgery has continued to evolve and progress. We now have a microsurgical reconstructive ladder. The microsurgical reconstruction ladder is based upon the early work on revascularization and replantation extending through the procedures that are described in this article.
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Affiliation(s)
- Scott M Tintle
- University of Pennsylvania, Philadelphia, PA, United States
| | - L Scott Levin
- University of Pennsylvania, Philadelphia, PA, United States.
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