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Hanada M, Kadota H, Fujiwara T, Setsu N, Endo M, Matsumoto Y, Nakashima Y. Immediate sciatic nerve reconstruction using an ipsilateral common peroneal nerve graft at the time of sarcoma resection. Microsurgery 2024; 44:e31034. [PMID: 36914614 DOI: 10.1002/micr.31034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 02/02/2023] [Accepted: 02/24/2023] [Indexed: 03/16/2023]
Abstract
BACKGROUND Concomitant resection of the sciatic nerve along with a malignant tumor is no longer a contraindication for limb-sparing surgery, as most of these patients remain ambulatory. However, sciatic nerve reconstruction after sarcoma resection is not commonly performed. Restoration of nerve function can improve patient quality of life. We describe our experience with four patients who underwent sciatic nerve reconstruction using an ipsilateral common peroneal nerve graft at the time of sarcoma resection. METHODS Because of the low chance of peroneal nerve recovery, the ipsilateral peroneal trunk was used as a graft to reconstruct the tibial trunk of the sciatic nerve. Two patients were men and two were women. Mean age was 45.3 years (range, 15-62). Mean sciatic nerve defect length was 9.4 cm (range, 8.5-12.0). Proximal thigh defects (three patients) were reconstructed with a double cable; the one patient with a distal thigh defect underwent single cable reconstruction. Mean operation time was 492 min (range, 428-682). RESULTS Mean length of the harvested peroneal trunks was 21 cm (range, 11-26). Mean graft length was 11.9 cm (range, 11-13). Postoperative course was uneventful in all four patients. One patient died of sarcoma lung metastasis and could not be evaluated. Three patients were followed for more than 2 years. Two patients achieved British Medical Research Council grade 4 plantar flexion; the remaining patient achieved grade 5 plantar flexion and grade 4 toe flexion. Semmes-Weinstein monofilament sensory testing showed loss of protective sensation on the plantar surface in all three. Musculoskeletal Tumor Society scores at last follow-up were 60.0%, 70.0%, and 43.3%, respectively. CONCLUSIONS Immediate sciatic nerve reconstruction using an ipsilateral common peroneal nerve graft avoids reconstruction delay and scar tissue formation, which is advantageous for nerve recovery. This technique may be considered when sciatic nerve resection is anticipated during sarcoma resection.
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Affiliation(s)
- M Hanada
- Department of Orthopedic Surgery, Kyushu Rosai Hospital, Kitakyushu, Japan
| | - H Kadota
- Department of Plastic Surgery, Kyushu University, Fukuoka, Japan
| | - T Fujiwara
- Department of Orthopedic Surgery, Kyushu University, Fukuoka, Japan
| | - N Setsu
- Department of Orthopedic Surgery, Kyushu University, Fukuoka, Japan
| | - M Endo
- Department of Orthopedic Surgery, Kyushu University, Fukuoka, Japan
| | - Y Matsumoto
- Department of Orthopedic Surgery, Kyushu University, Fukuoka, Japan
| | - Y Nakashima
- Department of Orthopedic Surgery, Kyushu University, Fukuoka, Japan
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Xie Y, Qin P, Guo T, Al Abed A, Lovell NH, Tsai D. Modulating individual axons and axonal populations in the peripheral nerve using transverse intrafascicular multichannel electrodes. J Neural Eng 2023; 20:046032. [PMID: 37536318 DOI: 10.1088/1741-2552/aced20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 08/03/2023] [Indexed: 08/05/2023]
Abstract
Objective.A transverse intrafascicular multichannel electrode (TIME) may offer advantages over more conventional cuff electrodes including higher spatial selectivity and reduced stimulation charge requirements. However, the performance of TIME, especially in the context of non-conventional stimulation waveforms, remains relatively unexplored. As part of our overarching goal of investigating stimulation efficacy of TIME, we developed a computational toolkit that automates the creation and usage ofin siliconerve models with TIME setup, which solves nerve responses using cable equations and computes extracellular potentials using finite element method.Approach.We began by implementing a flexible and scalable Python/MATLAB-based toolkit for automatically creating models of nerve stimulation in the hybrid NEURON/COMSOL ecosystems. We then developed a sciatic nerve model containing 14 fascicles with 1,170 myelinated (A-type, 30%) and unmyelinated (C-type, 70%) fibers to study fiber responses over a variety of TIME arrangements (monopolar and hexapolar) and stimulation waveforms (kilohertz stimulation and cathodic ramp modulation).Main results.Our toolkit obviates the conventional need to re-create the same nerve in two disparate modeling environments and automates bi-directional transfer of results. Our population-based simulations suggested that kilohertz stimuli provide selective activation of targeted C fibers near the stimulating electrodes but also tended to activate non-targeted A fibers further away. However, C fiber selectivity can be enhanced by hexapolar TIME arrangements that confined the spatial extent of electrical stimuli. Improved upon prior findings, we devised a high-frequency waveform that incorporates cathodic DC ramp to completely remove undesirable onset responses.Conclusion.Our toolkit allows agile, iterative design cycles involving the nerve and TIME, while minimizing the potential operator errors during complex simulation. The nerve model created by our toolkit allowed us to study and optimize the design of next-generation intrafascicular implants for improved spatial and fiber-type selectivity.
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Affiliation(s)
- Yuyang Xie
- Graduate School of Biomedical Engineering, UNSW Sydney, NSW 2052, Australia
| | - Peijun Qin
- Graduate School of Biomedical Engineering, UNSW Sydney, NSW 2052, Australia
| | - Tianruo Guo
- Graduate School of Biomedical Engineering, UNSW Sydney, NSW 2052, Australia
| | - Amr Al Abed
- Graduate School of Biomedical Engineering, UNSW Sydney, NSW 2052, Australia
| | - Nigel H Lovell
- Graduate School of Biomedical Engineering, UNSW Sydney, NSW 2052, Australia
- Tyree Institute of Health Engineering (IHealthE), UNSW Sydney, NSW 2052, Australia
| | - David Tsai
- Graduate School of Biomedical Engineering, UNSW Sydney, NSW 2052, Australia
- School of Electrical Engineering & Telecommunications, UNSW Sydney, NSW 2052, Australia
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Kim S, Oh YS, Lee K, Kim S, Maeng WY, Kim KS, Kim GB, Cho S, Han H, Park H, Wang M, Avila R, Xie Z, Ko K, Choi J, Je M, Lee H, Lee S, Koo J, Park I. Battery-Free, Wireless, Cuff-Type, Multimodal Physical Sensor for Continuous Temperature and Strain Monitoring of Nerve. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2206839. [PMID: 37069777 DOI: 10.1002/smll.202206839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 02/22/2023] [Indexed: 06/19/2023]
Abstract
Peripheral nerve injuries cause various disabilities related to loss of motor and sensory functions. The treatment of these injuries typically requires surgical operations for improving functional recovery of the nerve. However, capabilities for continuous nerve monitoring remain a challenge. Herein, a battery-free, wireless, cuff-type, implantable, multimodal physical sensing platform for continuous in vivo monitoring of temperature and strain from the injured nerve is introduced. The thin, soft temperature, and strain sensors wrapped around the nerve exhibit good sensitivity, excellent stability, high linearity, and minimum hysteresis in relevant ranges. In particular, the strain sensor integrated with circuits for temperature compensation provides reliable, accurate strain monitoring with negligible temperature dependence. The system enables power harvesting and data communication to wireless, multiple implanted devices wrapped around the nerve. Experimental evaluations, verified by numerical simulations, with animal tests, demonstrate the feasibility and stability of the sensor system, which has great potential for continuous in vivo nerve monitoring from an early stage to complete regeneration.
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Affiliation(s)
- Seunghwan Kim
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Yong Suk Oh
- Department of Mechanical Engineering, Changwon National University, Changwon, 51140, Republic of Korea
| | - Kwanghyoung Lee
- Department of Thoracic and Cardiovascular Surgery, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Seongchan Kim
- Center for Biomaterials, Korea Institute of Science and Technology, Seoul, 02841, Republic of Korea
| | - Woo-Youl Maeng
- School of Biomedical Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Kyung Su Kim
- School of Biomedical Engineering, Korea University, Seoul, 02841, Republic of Korea
- Interdisciplinary Program in Precision Public Health, Korea University, Seoul, 02841, Republic of Korea
| | - Ga-Been Kim
- Center for Biomaterials, Korea Institute of Science and Technology, Seoul, 02841, Republic of Korea
- School of Biomedical Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Seokjoo Cho
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Hyeonseok Han
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Hyunwoo Park
- School of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Mengqiu Wang
- State Key Laboratory of Structural Analysis for Industrial Equipment, Department of Engineering Mechanics, Dalian University of Technology, Dalian, 116023, P. R. China
- Ningbo Institute of Dalian University of Technology, Ningbo, 315016, P. R. China
| | - Raudel Avila
- Department of Mechanical Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Zhaoqian Xie
- State Key Laboratory of Structural Analysis for Industrial Equipment, Department of Engineering Mechanics, Dalian University of Technology, Dalian, 116023, P. R. China
- Ningbo Institute of Dalian University of Technology, Ningbo, 315016, P. R. China
- DUT-BSU Joint Institute, Dalian University of Technology, Dalian, 116023, P. R. China
| | - Kabseok Ko
- Qualcomm Institute, La Jolla, CA, 92093, USA
- Department of Electronics Engineering, Kangwon National University, Chuncheon, 24341, Republic of Korea
| | - Jungrak Choi
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Minkyu Je
- School of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Hyojin Lee
- Center for Biomaterials, Korea Institute of Science and Technology, Seoul, 02841, Republic of Korea
| | - Sungho Lee
- Department of Thoracic and Cardiovascular Surgery, Korea University College of Medicine, Seoul, 02841, Republic of Korea
| | - Jahyun Koo
- School of Biomedical Engineering, Korea University, Seoul, 02841, Republic of Korea
- Interdisciplinary Program in Precision Public Health, Korea University, Seoul, 02841, Republic of Korea
| | - Inkyu Park
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
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Lubelski D, Halsey J, Suk I, Tuffaha S, Osgood G, Belzberg AJ. Novel Approach of Femur Shortening With Insertion of Expandable Rod to Achieve End-to-End Repair of Sciatic Nerve Laceration. Oper Neurosurg (Hagerstown) 2023; 24:455-459. [PMID: 36701656 DOI: 10.1227/ons.0000000000000569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 09/29/2022] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Sciatic nerve injuries are challenging for diagnosis and treatment. Particularly in proximally located high-grade injuries, neurorrhaphy often has poor outcomes. Most advocate autologous grafting and some more recently have suggested the value of knee flexion braces to facilitate end-to-end repair. OBJECTIVE To describe a case of femur shortening to facilitate tension-free, end-to-end sciatic nerve neurorrhaphy. METHODS The patient was a 17-year-old man who was injured by the propeller of a motor boat and suffered a series of lacerations to both lower extremities including transection of his right sciatic nerve in the proximal thigh. After extensive mobilization of the nerve, a greater than 7-cm gap was still present. The patient was treated with femur shortening to facilitate end-to-end coaptation. He subsequently had an expandable rod placed which was lengthened 1 mm per day until his leg length was symmetric. RESULTS Within 7 months postoperatively, the patient had an advancing Tinel sign and paresthesias to the dorsum of his foot. Nine months postoperatively, he had early mobility in his plantarflexion. CONCLUSION We present a novel method of femur shortening with insertion of an expandable rod to facilitate direct end-to-end and tension-free sciatic nerve neurorrhaphy in a proximally located injury. Furthermore, larger scale and comparative studies are warranted to further explore this and other techniques.
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Affiliation(s)
- Daniel Lubelski
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jordan Halsey
- Department of Plastic and Reconstructive Surgery, Johns Hopkins All Children's Hospital, St Petersburg, Florida, USA
| | - Ian Suk
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Sami Tuffaha
- Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Greg Osgood
- Department of Orthopedic Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Allan J Belzberg
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Sarcon AK, Li NY, Houdek MT, Moran SL. Restoration of hamstring function following sciatic nerve resection at the greater sciatic foramen with reconstruction involving acellular nerve allograft and vascularized sural nerve autograft: A case report. Microsurgery 2022; 42:824-828. [PMID: 36177748 DOI: 10.1002/micr.30970] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 08/25/2022] [Accepted: 09/16/2022] [Indexed: 11/10/2022]
Abstract
Segmental loss of the sciatic nerve secondary to oncologic resection or trauma is detrimental to hamstring and leg function. The diameter of this nerve and the length of its axons spanning the lower extremity create significant challenges in reconstruction and optimizing return of sensory or motor function. The purpose of this report is to describe outcomes of a free vascularized sural nerve graft to preserve hamstring function in a large proximal sciatic nerve defect beginning at the greater sciatic foramen. A 44-year-old female underwent neoadjuvant chemotherapy and radiation for treatment of a left sciatic nerve synovial cell sarcoma. The patient underwent R0 resection of the proximal left sciatic nerve resulting in a 15 cm defect. An ipsilateral vascularized sural nerve graft was used to reconstruct the medial aspect of the sciatic nerve, prioritizing the tibial division, in an effort to restore hamstring function and plantar sensation. A 5 cm allograft nerve was added to the cutaneous branches of the sural nerve graft to better span the large defect and reconstruct the lateral aspect of the nerve. The patient's postoperative course was uneventful. At 1-year follow-up, the patient showed MRC grade 4/5 strength with knee flexion and steady gait pattern with a left ankle-foot orthosis. Outcomes support the use of a single vascularized nerve graft alongside acellular nerve allograft to restore motor function in large diameter and large defect mixed nerve injuries.
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Affiliation(s)
- Aida K Sarcon
- Department of Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Neill Y Li
- Department of Orthopaedic Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Matthew T Houdek
- Department of Orthopaedic Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Steven L Moran
- Department of Orthopaedic Surgery, Mayo Clinic, Rochester, Minnesota, USA.,Division of Plastic Surgery, Department of Surgery, Mayo Clinic, Rochester, Minnesota, USA
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Vallejo FA, Diaz A, Errante EL, Smartz T, Khan A, Silvera R, Brooks AE, Lee YS, Burks SS, Levi AD. Systematic review of the therapeutic use of Schwann cells in the repair of peripheral nerve injuries: Advancements from animal studies to clinical trials. Front Cell Neurosci 2022; 16:929593. [PMID: 35966198 PMCID: PMC9372346 DOI: 10.3389/fncel.2022.929593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 07/05/2022] [Indexed: 11/26/2022] Open
Abstract
Objective To systematically evaluate the literature on the therapeutic use of Schwann cells (SC) in the repair of peripheral nerve injuries. Methods The Cochrane Library and PubMed databases were searched using terms [(“peripheral nerve injury” AND “Schwann cell” AND “regeneration”) OR (“peripheral nerve injuries”)]. Studies published from 2008 to 2022 were eligible for inclusion in the present study. Only studies presenting data from in-vivo investigations utilizing SCs in the repair of peripheral nerve injuries qualified for review. Studies attempting repair of a gap of ≥10 mm were included. Lastly, studies needed to have some measure of quantifiable regenerative outcome data such as histomorphometry, immunohistochemical, electrophysiology, or other functional outcomes. Results A search of the PubMed and Cochrane databases revealed 328 studies. After screening using the abstracts and methods, 17 studies were found to meet our inclusion criteria. Good SC adherence and survival in conduit tubes across various studies was observed. Improvement in morphological and functional outcomes with the use of SCs in long gap peripheral nerve injuries was observed in nearly all studies. Conclusion Based on contemporary literature, SCs have demonstrated clear potential in the repair of peripheral nerve injury in animal studies. It has yet to be determined which nerve conduit or graft will prove superior for delivery and retention of SCs for nerve regeneration. Recent developments in isolation and culturing techniques will enable further translational utilization of SCs in future clinical trials.
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Affiliation(s)
- Frederic A. Vallejo
- Department of Neurosurgery, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Anthony Diaz
- Department of Neurosurgery, University of Connecticut, Farmington, CT, United States
| | - Emily L. Errante
- Department of Neurosurgery, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Taylor Smartz
- Department of Neurosurgery, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Aisha Khan
- Department of Neurosurgery, University of Miami Miller School of Medicine, Miami, FL, United States
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Risset Silvera
- Department of Neurosurgery, University of Miami Miller School of Medicine, Miami, FL, United States
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Adriana E. Brooks
- Department of Neurosurgery, University of Miami Miller School of Medicine, Miami, FL, United States
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Yee-Shuan Lee
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Stephen Shelby Burks
- Department of Neurosurgery, University of Miami Miller School of Medicine, Miami, FL, United States
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Allan D. Levi
- Department of Neurosurgery, University of Miami Miller School of Medicine, Miami, FL, United States
- Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
- *Correspondence: Allan D. Levi
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Defects of the sciatic nerve and its divisions treated by direct suturing in 90 degrees knee flexion: report on the first clinical series. Eur J Trauma Emerg Surg 2022; 48:4955-4962. [PMID: 35857068 DOI: 10.1007/s00068-022-02034-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 06/05/2022] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To evaluate functional results after treatment of large defects of the sciatic nerve and its divisions by direct nerve suturing in high knee flexion. METHODS A retrospective review was conducted in patients treated for lower extremity nerve defects between 2011 and 2019. Inclusion criteria were a defect > 2 cm with a minimal follow-up period of 2 years for the sciatic nerve and 1 year for its divisions. Nerve defects were bridged by an end-to-end suture with the knee flexed at 90° for 6 weeks. Functional results were assessed based on the Medical Research Council's grading system. RESULTS Seventeen patients with a mean age of 27.6 years were included. They presented with seven sciatic nerve defects and ten division defects, including eight missile injuries. The mean time to surgery was 12.3 weeks and the mean nerve defect length was 5 cm. Overall, 21 nerve sutures were performed, with eight in the tibial distribution and 13 in the fibular distribution. Post-operatively, there was no significant knee stiffness related to the immobilization. The mean follow-up time was 24.5 months. Meaningful motor and sensory recovery were observed after 7 of 8 sutures in the tibial distribution and 11 of 13 sutures in the fibular distribution. A functional sural triceps muscle with protective sensibility of the sole was restored in all patients. There were no differences according to the injury mechanisms. CONCLUSION Temporary knee flexion at 90° allows for direct coaptation of sciatic nerve defects up to 8 cm, with promising results no matter the level or mechanism of injury.
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Errante EL, Diaz A, Smartz T, Khan A, Silvera R, Brooks AE, Lee YS, Burks SS, Levi AD. Optimal Technique for Introducing Schwann Cells Into Peripheral Nerve Repair Sites. Front Cell Neurosci 2022; 16:929494. [PMID: 35846565 PMCID: PMC9283978 DOI: 10.3389/fncel.2022.929494] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/08/2022] [Indexed: 11/13/2022] Open
Abstract
Peripheral nerve injury (PNI) is found in a relatively large portion of trauma patients. If the injury is severe, such as with the presence of a long segmental gap, PNI can present a challenge for treatment. The current clinical standard of nerve harvest for the repair of long segmental gap PNI can lead to many potential complications. While other methods have been utilized, recent evidence indicates the relevance of cell therapies, particularly through the use of Schwann cells, for the treatment of PNI. Schwann cells (SCs) are integral in the regeneration and restoration of function following PNI. SCs are able to dedifferentiate and proliferate, remove myelin and axonal debris, and are supportive in axonal regeneration. Our laboratory has demonstrated that SCs are effective in the treatment of severe PNI when axon guidance channels are utilized. However, in order for this treatment to be effective, optimal techniques for cellular placement must be used. Thus, here we provide relevant background information, preclinical, and clinical evidence for our method in the treatment of severe PNI through the use of SCs and axon guidance channels.
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Affiliation(s)
- Emily L. Errante
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
- Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Anthony Diaz
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Taylor Smartz
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Aisha Khan
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
- Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Risset Silvera
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
- Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Adriana E. Brooks
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
- Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Yee-Shuan Lee
- Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, FL, United States
| | - S. Shelby Burks
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
- Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Allan D. Levi
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, United States
- Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL, United States
- *Correspondence: Allan D. Levi
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9
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Im JH, Shin SH, Lee MK, Lee SR, Lee JJ, Chung YG. Evaluation of anatomical and histological characteristics of human peripheral nerves: as an effort to develop an efficient allogeneic nerve graft. Cell Tissue Bank 2022; 23:591-606. [DOI: 10.1007/s10561-022-09998-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 02/13/2022] [Indexed: 12/14/2022]
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10
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Acharya AM, Bhat AK, Jyothish G, Mukadam A. Delayed Presentation of Sciatic Nerve Injury with Gap: A Case Report with a Unique Solution from the Past. JBJS Case Connect 2022; 12:01709767-202203000-00051. [PMID: 35171848 DOI: 10.2106/jbjs.cc.21.00192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
CASE A 35-year-old farmer presented with a foot ulcer on his left flail foot because of a sciatic nerve injury of 1-year duration. A gap of 11 cm was observed in the sciatic nerve for which he underwent 2-staged pedicled peroneal nerve grafting and posterior bone block procedure for the ankle. He had S3 grade sensation at 5-year follow-up without any recurrence of ulcer and a stable foot without external support for walking. CONCLUSION Staged pedicled peroneal nerve grafting with a posterior bone block procedure is a viable solution for very large sciatic nerve defect with predictable results.
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Affiliation(s)
- Ashwath M Acharya
- Unit of Hand and Microsurgery, Department of Orthopaedics, Kasturba Medical College Hospital, Manipal, Manipal Academy of Higher Education, India
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Peng Y, Lin H. [Regulatory role of long non-coding RNA in peripheral nerve injury and neural regeneration]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 2021; 35:1051-1056. [PMID: 34387437 DOI: 10.7507/1002-1892.202103107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Objective To summarize the regulatory role of long non-coding RNA (lncRNA) in peripheral nerve injury (PNI) and neural regeneration. Methods The characteristics and mechanisms of lncRNA were summarized and its regulatory role in PNI and neural regeneration were elaborated by referring to relevant domestic and foreign literature in recent years. Results Neuropathic pain and denervated muscle atrophy are common complications of PNI, affecting patients' quality of life. Numerous lncRNAs are upregulated after PNI, which promote the progress of neuropathic pain by regulating nerve excitability and neuroinflammation. Several lncRNAs are found to promote the progress of denervated muscle atrophy. Importantly, peripheral nerve regeneration occurs after PNI. LncRNAs promote peripheral nerve regeneration through promoting neuronal axonal outgrowth and the proliferation and migration of Schwann cells. Conclusion At present, the research on lncRNA regulating PNI and neural regeneration is still in its infancy. The specific mechanism remains to be further explored. How to achieve clinical translation of experimental results is also a major challenge for future research.
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Affiliation(s)
- Ying Peng
- Trauma Clinic Medicine Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 201600, P.R.China
| | - Haodong Lin
- Trauma Clinic Medicine Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 201600, P.R.China
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12
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Burks SS, Diaz A, Haggerty AE, Oliva NDL, Midha R, Levi AD. Schwann cell delivery via a novel 3D collagen matrix conduit improves outcomes in critical length nerve gap repairs. J Neurosurg 2021; 135:1241-1251. [PMID: 33607621 DOI: 10.3171/2020.8.jns202349] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 08/25/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The current clinical standard of harvesting a nerve autograft for repair of long-segment peripheral nerve injuries (PNIs) is associated with many potential complications. Guidance channels offer an alternative therapy. The authors investigate whether autologous Schwann cells (SCs) implanted within a novel collagen-glycosaminoglycan conduit will improve axonal regeneration in a long-segment PNI model. METHODS Novel NeuraGen 3D collagen matrix conduits were implanted with autologous SCs to investigate axonal regeneration across a critical size defect (13 mm) in male Fischer rat sciatic nerve. Reversed sciatic nerve autografts served as positive controls, and conduits filled with serum only as negative controls. Electrophysiological assessments were made in vivo. Animals were killed at 4 or 16 weeks postinjury, muscle weights were measured, and grafts underwent immunohistochemical and morphometric analysis. RESULTS SC survival was confirmed by the presence of green fluorescent protein-labeled SCs within regenerated fibers. Regeneration and elongation of myelinated axons in all segments of the graft were significantly enhanced at 16 weeks in the SC-filled conduits compared to the conduit alone and were statistically similar to those of the autograft. Nerves repaired with SC-filled conduits exhibited onset latencies and nerve conduction amplitudes similar to those of the contralateral controls and autograft (p < 0.05). Adding SCs to the conduit also significantly reduced muscle atrophy compared to conduit alone (p < 0.0001). CONCLUSIONS Repair of long-segment PNI of rat sciatic nerve is significantly enhanced by SC-filled NeuraGen 3D conduits. Improvements in the total number of myelinated axons, axon diameter, and myelin thickness throughout SC-filled conduits allow for significant recovery in nerve conduction and a decrease in muscle atrophy.
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Affiliation(s)
- S Shelby Burks
- 1Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida; and
| | - Anthony Diaz
- 1Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida; and
| | - Agnes E Haggerty
- 1Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida; and
| | - Natalia de la Oliva
- 1Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida; and
| | - Rajiv Midha
- 2Department of Clinical Neurosciences and Hotchkiss Brain Institute, University of Calgary, Alberta, Canada
| | - Allan D Levi
- 1Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida; and
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13
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Burks SS, Levi AD. Commentary: A Porcine Model of Peripheral Nerve Injury Enabling Ultra-Long Regenerative Distances: Surgical Approach, Recovery Kinetics, and Clinical Relevance. Neurosurgery 2020; 87:E520-E521. [PMID: 32392340 DOI: 10.1093/neuros/nyaa121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 02/20/2020] [Indexed: 11/15/2022] Open
Affiliation(s)
| | - Allan D Levi
- Department of Neurological Surgery, University of Miami, Miami, Florida
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14
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Perez-Roman RJ, Shelby Burks S, Debs L, Cajigas I, Levi AD. The Risk of Peripheral Nerve Tumor Biopsy in Suspected Benign Etiologies. Neurosurgery 2020; 86:E326-E332. [PMID: 31927583 DOI: 10.1093/neuros/nyz549] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/05/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Peripheral nerve sheath tumors (PNSTs) are tumors with unique clinical and imaging features that present to a variety of physicians. These lesions are often referred for biopsy, which can put nerve fascicles at risk. Preoperative biopsy may cause distortion of normal anatomic planes, making definitive resection difficult. OBJECTIVE To evaluate the neurological risks of preoperative biopsy in benign PNSTs. METHODS Surgical cases collected retrospectively using a prospectively established database of PNSTs treated by a single surgeon between 1997 and 2019. Patients were dichotomized depending on preoperative biopsy. The effects of biopsy were assessed via history and physical examination both pre- and postdefinitive resection. RESULTS A total of 151 cases were included. Only 23.2% (35) of patients underwent preoperative biopsy, but 42.9% of these experienced new or worsening neurological examination immediately following biopsy. After definitive resection, the rate of neurological deficit was significantly different between the 2 groups with 60% of biopsy patients and 19% of those patients not biopsied experiencing decline in examination (F = 25.72, P < .001). Odds ratio for any postoperative deficit for biopsy was 6.40 (CI [2.8, 14.55], P < .001). Univariate logistic regression of neurological deficit with patient age, sex, tumor type, and biopsy status showed that only biopsy was associated with the occurrence of any postoperative deficit. CONCLUSION Biopsy of benign PNSTs is associated with a high rate of neurological deficit both immediately following the procedure and after definitive resection. Careful selection is imperative prior to proceeding with biopsy of nerve sheath tumors exhibiting benign features given the unacceptably high rate of neurological decline.
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Affiliation(s)
- Roberto J Perez-Roman
- Miami Project to Cure Paralysis, Department of Neurological Surgery, Miller School of Medicine, University of Miami, Miami, Florida
| | - S Shelby Burks
- Miami Project to Cure Paralysis, Department of Neurological Surgery, Miller School of Medicine, University of Miami, Miami, Florida
| | - Luca Debs
- Miami Project to Cure Paralysis, Department of Neurological Surgery, Miller School of Medicine, University of Miami, Miami, Florida
| | - Iahn Cajigas
- Miami Project to Cure Paralysis, Department of Neurological Surgery, Miller School of Medicine, University of Miami, Miami, Florida
| | - Allan D Levi
- Miami Project to Cure Paralysis, Department of Neurological Surgery, Miller School of Medicine, University of Miami, Miami, Florida
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15
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Fang Z, Ge X, Chen X, Xu Y, Yuan WE, Ouyang Y. Enhancement of sciatic nerve regeneration with dual delivery of vascular endothelial growth factor and nerve growth factor genes. J Nanobiotechnology 2020; 18:46. [PMID: 32169062 PMCID: PMC7071717 DOI: 10.1186/s12951-020-00606-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 03/09/2020] [Indexed: 02/14/2023] Open
Abstract
BACKGROUND Peripheral nerve injury is one common clinical disease worldwide, in which sciatic nerve is anatomically the most challenging to regenerate given its length and large cross-sectional area. For the present, autologous nerve grafting remains to be the most ideal strategy when treating with sciatic nerve injury. However, this method sacrifices healthy nerves and requires highly intensive surgery, still calling for other advanced alternatives for nerve grafting. RESULTS In this study, we utilized previously well-established gene delivery system to dually deliver plasmid DNA (pDNA) encoding vascular endothelial growth factor (VEGF) and nerve growth factor (NGF), exploring therapeutics for sciatic nerve injury. Low-molecular-weight branched polyethylenimine (bPEI) was constructed as the backbone structure of gene vectors, and it was further crosslinked to synthesize degradable polycations via the conjugation of dialdehydes. Potential synergistic effect between VEGF and NGF proteins were observed on rat sciatic nerve crush injury model in this study. CONCLUSIONS We concluded that dual delivery of plasmid VEGF and NGF as gene therapy could enhance sciatic nerve regeneration.
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Affiliation(s)
- Zhiwei Fang
- Department of Orthopedics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China.,Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.,Shanghai Sixth People's Hospital East Affiliated to Shanghai University of Medicine & Health Sciences, Shanghai, 201306, China
| | - Xuemei Ge
- School of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Xuan Chen
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yang Xu
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Wei-En Yuan
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Yuanming Ouyang
- Department of Orthopedics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China. .,Shanghai Sixth People's Hospital East Affiliated to Shanghai University of Medicine & Health Sciences, Shanghai, 201306, China.
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Abstract
Management of sciatic nerve injuries can be difficult for surgeons without a special interest in nerve surgery as they would only treat a handful of such cases for many years. Sciatic nerve defects pose the greatest repair challenges, with nerve grafting producing mixed results because of the large size of the nerve in both diameter and length. This article first presents the peculiarities of sciatic nerve defects management, based on the authors experience and a literature review. Various issues are dealt with: When to operate depending on the injury mechanism? What are the results of nerve autografting and allografting? On which component should the repair focus in very large defects? Subsequently, alternatives to conventional nerve grafting are proposed. The authors stress the usefulness of direct nerve suture with knee flexion at 90 degrees, which permits bridging of gaps as much as 8 cm in length. For larger defects, other procedures should be considered: long vascularized nerve grafting in complete lesions, short grafting with knee flexed, or tendon transfers in partial lesions.
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17
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Mathieu L, Pfister G, Murison JC, Oberlin C, Belkheyar Z. Missile Injury of the Sciatic Nerve: Observational Study Supporting Early Exploration and Direct Suture With Flexed Knee. Mil Med 2019; 184:e937-e944. [PMID: 31004436 DOI: 10.1093/milmed/usz087] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 02/21/2019] [Indexed: 11/13/2022] Open
Abstract
Missile injuries of the sciatic nerve are frequently encountered in modern violent conflicts. Gunshot and fragment wounds may cause large nerve defects, for which management is challenging. The great size of the sciatic nerve, in both diameter and length, explains the poor results of nerve repair using autografts or allografts. To address this issue, we used a simple technique consisting of a direct suture of the sciatic nerve combined with knee flexion for 6 weeks. Despite a published series showing that this procedure gives better results than sciatic nerve grafting, it remains unknown or underutilized. The purpose of this cases study is to highlight the efficiency of direct sciatic nerve coaptation with knee flexed through three cases with missile injuries at various levels. At the follow-up of two years, all patients were pain free with a protective sensory in the sole and M3+ or M4 gastrocnemius muscles, regardless of the injury level. Recovery was also satisfying in the fibular portion, except for the very proximal lesion. No significant knee stiffness was noticed, including in a case suffering from an associated distal femur fracture. Key points to enhance functional recovery are early nerve repair (as soon as definitive bone fixation and stable soft-tissue coverage are achieved) and careful patient selection.
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Affiliation(s)
- Laurent Mathieu
- Clinic of Orthopedic, Trauma and Reconstructive Surgery, Percy Military Teaching Hospital, 101 Avenue Henri Barbusse 92140 Clamart, France
- Department of Surgery, French Military Health Service Academy, Ecole du Val-de-Grâce, 1 place Alphone Laveran 75015 Paris, France
| | - Georges Pfister
- Clinic of Orthopedic, Trauma and Reconstructive Surgery, Percy Military Teaching Hospital, 101 Avenue Henri Barbusse 92140 Clamart, France
| | - James Charles Murison
- Clinic of Orthopedic, Trauma and Reconstructive Surgery, Percy Military Teaching Hospital, 101 Avenue Henri Barbusse 92140 Clamart, France
| | - Christophe Oberlin
- Mont-Louis Private Hospital, 8 rue de la Folie-Regnault 75011 Paris, France
| | - Zoubir Belkheyar
- Mont-Louis Private Hospital, 8 rue de la Folie-Regnault 75011 Paris, France
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18
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Meng D, Chen H, Lin Y, Lin H, Hou C. Transferring of femoral nerve motor branches for high-level sciatic nerve injury: a cadaver feasibility study. Acta Neurochir (Wien) 2019; 161:279-286. [PMID: 30483983 DOI: 10.1007/s00701-018-3746-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 11/21/2018] [Indexed: 11/30/2022]
Abstract
BACKGROUND Sciatic nerve injuries cause significant disability. We propose here a novel reconstructive procedure of transferring the motor branches of the femoral nerve as donor nerves to reconstruct both the peroneal and tibial nerve function as a novel approach to treat high sciatic nerve injury. METHODS The autopsies of donor nerves (vastus lateralis nerve branch (VLN), vastus medialis nerve branch (VMN), saphenous nerve (SAN)) and respective recipient nerves (deep peroneal nerve branch (DPN), medial gastrocnemius nerve branch (MGN), sural nerve (SN)) were conducted in six fresh-frozen lower limbs. The distance between the origin or bifurcation points of the nerves to the head of fibula and the diameter of the end at the coaptation site were measured. The feasibility of tensionless direct suturing or grafting between the donor nerves and the recipient was evaluated. Finally, the nerve end at the coaptation site was harvested for observation with toluidine blue staining and nerve fiber count. RESULTS The mean diameter of the VMN, VLN, MGN, DPN, SAN, and SN nerves were 1.5 ± 0.1, 1.4 ± 0.1, 1.3 ± 0.1, 2.3 ± 0.1, 2.1 ± 0.3, and 1.3 ± 0.2 mm, respectively. Histological observation showed that the abovementioned six nerve bundles had a respective nerve fiber number of 392 ± 27, 205 ± 520, 219 ± 67, 394 ± 50, 308 ± 77, and 335 ± 49. A total of 5/6 specimens needed grafting for a length ranging from 5 to 15 cm to bridge the VMN-MGN, 6/6 needed a graft length of 10-20 cm for VLN-DPN bridging, and 2/6 needed a graft length of 0-4 cm for SAN-SN bridging. CONCLUSION The study demonstrated the feasibility of the transferring femoral nerve branches to sciatic nerve branches to restore the function for sciatic injury.
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Affiliation(s)
- Depeng Meng
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai, 200003, People's Republic of China
| | - Huihao Chen
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai, 200003, People's Republic of China
| | - Yaofa Lin
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai, 200003, People's Republic of China
| | - Haodong Lin
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai, 200003, People's Republic of China.
| | - Chunlin Hou
- Department of Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai, 200003, People's Republic of China
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19
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Moore AM, Krauss EM, Parikh RP, Franco MJ, Tung TH. Femoral nerve transfers for restoring tibial nerve function: an anatomical study and clinical correlation: a report of 2 cases. J Neurosurg 2018; 129:1024-1033. [DOI: 10.3171/2017.5.jns163076] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Sciatic nerve injuries cause debilitating functional impairment, particularly when the injury mechanism and level preclude reconstruction with primary grafting. The purpose of this study was to demonstrate the anatomical feasibility of nerve transfers from the distal femoral nerve terminal branches to the tibial nerve and to detail the successful restoration of tibial function using the described nerve transfers.Six cadaveric legs were dissected for anatomical analysis and the development of tension-free nerve transfers from femoral nerve branches to the tibial nerve. In 2 patients with complete tibial and common peroneal nerve palsies following sciatic nerve injury, terminal branches of the femoral nerve supplying the vastus medialis and vastus lateralis muscles were transferred to the medial and lateral gastrocnemius branches of the tibial nerve. Distal sensory transfer of the saphenous nerve to the sural nerve was also performed. Patients were followed up for lower-extremity motor and sensory recovery up to 18 months postoperatively.Consistent branching patterns and anatomical landmarks were present in all dissection specimens, allowing for reliable identification, neurolysis, and coaptation of donor femoral and saphenous nerve branches to the recipients. Clinically, the patients obtained Medical Research Council Grade 3 and 3+ plantar flexion by 18 months postoperatively. Improved strength was accompanied by improved ambulation in both patients and by a return to competitive sports in 1 patient. Sensory recovery was demonstrated by an advancing Tinel sign in both patients.This study illustrates the clinical success and anatomical feasibility of femoral nerve to tibial nerve transfers after proximal sciatic nerve injury.
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20
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Kohn C, Klemens JM, Kascholke C, Murthy NS, Kohn J, Brandenburger M, Hacker MC. Dual-component collagenous peptide/reactive oligomer hydrogels as potential nerve guidance materials - from characterization to functionalization. Biomater Sci 2018; 4:1605-1621. [PMID: 27722483 DOI: 10.1039/c6bm00397d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Toward a new generation of improved nerve guidance conduits (NGCs), novel biomaterials are required to address pressing clinical shortcomings in peripheral nerve regeneration (PNR) and to promote biological performance. A dual-component hydrogel system formed by cross-linking reaction between maleic anhydride groups in an oligomeric building block for cross-linking of free amine functionalities in partially hydrolyzed collagen is formulated for continuous processing and NGC fabrication. The influence of the gelation base is optimized for processing from a double syringe delivery system with a static mixer. A hydrophilic low-concentrated base was introduced to control network formation and to utilize highly reactive macromers for gelation. Cross-linking extent and building block conversion were improved and homogenous monoliths were fabricated. Chemically derivatized hydrogels were obtained by conversion of a fraction of anhydride groups in the oligomeric precursor with monovalent primary amine-containing grafting molecules prior to gelation. Network stability in functionalized hydrogels was maintained and cationic moieties were implement to the gel that promoted in vitro cell attachment and spreading irrespective of mechanical stiffness. A molding strategy was introduced that allowed for fabrication of flexible tubular conduits in tunable dimensions and with chemically patterned structures. These hydrogel-based conduits hold promise for the next generation NGCs with integrated chemical cues for PNR.
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Affiliation(s)
- C Kohn
- Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, 04317 Leipzig, Germany.
| | - J M Klemens
- Fraunhofer Research Institution for Marine Biotechnology EMB, 23562 Lübeck, Germany
| | - C Kascholke
- Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, 04317 Leipzig, Germany.
| | - N S Murthy
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854-8066, USA
| | - J Kohn
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854-8066, USA
| | - M Brandenburger
- Fraunhofer Research Institution for Marine Biotechnology EMB, 23562 Lübeck, Germany
| | - M C Hacker
- Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, 04317 Leipzig, Germany.
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21
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Use of Vascularized Sural Nerve Grafts for Sciatic Nerve Reconstruction After Malignant Bone and Soft Tissue Tumor Resection in the Lower Legs. Ann Plast Surg 2018; 80:379-383. [PMID: 29389699 DOI: 10.1097/sap.0000000000001315] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Vascularized nerve grafting is normally associated with a good outcome, but can be difficult to use for nerve reconstruction in patients with long defects of the sciatic nerve given the graft thickness. We report 3 cases of large defect sciatic nerve reconstruction using the bilateral sural nerves of the lower legs harvested together with the fascia and lesser saphenous vein to form a vascularized flap. METHODS The subjects were 3 patients who required the reconstruction of a 10-cm or longer segment of the sciatic nerve. Priority was given to restoring sensation in the plantar region such that reconstruction of the sensory nerves corresponding to the tibial region. RESULTS Two patients were followed up for long term. There was some persistent perceptual deficit in the foot, minimal protective sensation had been achieved. CONCLUSIONS We were able to selectively reconstruct the sensory nerves to achieve sensation in the soles of the feet by using sural nerve grafts from both legs. As the prognosis for the underlying condition in cases necessitating this procedure is often poor, the costs and benefits of reconstruction should always be weighed carefully for each individual patient.
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22
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Bora Karslı P, Karaahmet ÖZ, Ünlü E, Gürçay E, Çakcı FA. Siyatik sinir yaralanmalarında etiyolojik faktörler ile elektrofizyolojik bulguların değerlendirilmesi. EGE TIP DERGISI 2017. [DOI: 10.19161/etd.390329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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23
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Gersey ZC, Burks SS, Anderson KD, Dididze M, Khan A, Dietrich WD, Levi AD. First human experience with autologous Schwann cells to supplement sciatic nerve repair: report of 2 cases with long-term follow-up. Neurosurg Focus 2017; 42:E2. [PMID: 28245668 DOI: 10.3171/2016.12.focus16474] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Long-segment injuries to large peripheral nerves present a challenge to surgeons because insufficient donor tissue limits repair. Multiple supplemental approaches have been investigated, including the use of Schwann cells (SCs). The authors present the first 2 cases using autologous SCs to supplement a peripheral nerve graft repair in humans with long-term follow-up data. METHODS Two patients were enrolled in an FDA-approved trial to assess the safety of using expanded populations of autologous SCs to supplement the repair of long-segment injuries to the sciatic nerve. The mechanism of injury included a boat propeller and a gunshot wound. The SCs were obtained from both the sural nerve and damaged sciatic nerve stump. The SCs were expanded and purified in culture by using heregulin β1 and forskolin. Repair was performed with sural nerve grafts, SCs in suspension, and a Duragen graft to house the construct. Follow-up was 36 and 12 months for the patients in Cases 1 and 2, respectively. RESULTS The patient in Case 1 had a boat propeller injury with complete transection of both sciatic divisions at midthigh. The graft length was approximately 7.5 cm. In the postoperative period the patient regained motor function (Medical Research Council [MRC] Grade 5/5) in the tibial distribution, with partial function in peroneal distribution (MRC Grade 2/5 on dorsiflexion). Partial return of sensory function was also achieved, and neuropathic pain was completely resolved. The patient in Case 2 sustained a gunshot wound to the leg, with partial disruption of the tibial division of the sciatic nerve at the midthigh. The graft length was 5 cm. Postoperatively the patient regained complete motor function of the tibial nerve, with partial return of sensation. Long-term follow-up with both MRI and ultrasound demonstrated nerve graft continuity and the absence of tumor formation at the repair site. CONCLUSIONS Presented here are the first 2 cases in which autologous SCs were used to supplement human peripheral nerve repair in long-segment injury. Both patients had significant improvement in both motor and sensory function with correlative imaging. This study demonstrates preliminary safety and efficacy of SC transplantation for peripheral nerve repair.
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Affiliation(s)
- Zachary C Gersey
- Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - S Shelby Burks
- Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Kim D Anderson
- Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Marine Dididze
- Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Aisha Khan
- Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - W Dalton Dietrich
- Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Allan D Levi
- Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
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24
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Tubbs RS, Collin PG, D'Antoni AV, Loukas M, Oskouian RJ, Spinner RJ. Sciatic Nerve Intercommunications: New Finding. World Neurosurg 2017; 98:176-181. [DOI: 10.1016/j.wneu.2016.10.118] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 10/22/2016] [Accepted: 10/24/2016] [Indexed: 11/28/2022]
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25
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Burks SS, Cajigas I, Jose J, Levi AD. Intraoperative Imaging in Traumatic Peripheral Nerve Lesions: Correlating Histologic Cross-Sections with High-Resolution Ultrasound. Oper Neurosurg (Hagerstown) 2017; 13:196-203. [DOI: 10.1093/ons/opw016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 11/07/2016] [Indexed: 11/13/2022] Open
Abstract
Abstract
BACKGROUND: Intraoperative ultrasound (US) has been used as a guide during surgery to better identify deep neuroanatomical structures.
OBJECTIVE: To correlate histologic cross-sections from nerve samples taken at the time of surgery with axial, high-resolution US images at similar locations and validate this important tool for intraoperative guidance in nerve surgery.
METHODS: Three subjects undergoing nerve repair procedures after traumatic nerve injuries were enrolled prospectively. US images captured at the time of surgery were later matched with gross anatomic cross-sections and fascicular anatomy compared across modalities.
RESULTS: In cases 1 and 3, neuromatous tissue spanned the entire cross-section of the common peroneal and upper trunk of the brachial plexus, respectively. In case 2, only a portion of the sciatic nerve was involved with neuroma. Intraoperative US aided in differentiating normal peripheral nerve from neuroma in all 3 cases and helped minimize the disruption of healthy peripheral nerve tissue.
CONCLUSION: Intraoperative US correlates well with anatomic sections removed at the time of surgery. The ability to noninvasively image the peripheral nerve along with compound nerve action potentials can greatly assist in determining the extent of neurolysis, resection, and grafting and is a useful adjunct for intraoperative decision-making. This report serves to highlight the role of US and validate its use in peripheral nerve surgery for trauma.
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Affiliation(s)
- S. Shelby Burks
- Department of Neurological Surgery and The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Iahn Cajigas
- Department of Neurological Surgery and The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Jean Jose
- Department of Radiology, University of Miami/Jackson Memorial Hospital, Miami, Florida
| | - Allan D. Levi
- Department of Neurological Surgery and The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
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Tomaszewski KA, Graves MJ, Henry BM, Popieluszko P, Roy J, Pękala PA, Hsieh WC, Vikse J, Walocha JA. Surgical anatomy of the sciatic nerve: A meta-analysis. J Orthop Res 2016; 34:1820-1827. [PMID: 26856540 DOI: 10.1002/jor.23186] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Accepted: 02/03/2016] [Indexed: 02/04/2023]
Abstract
The sciatic nerve has varying anatomy with respect to the piriformis muscle. Understanding this variant anatomy is vital to avoiding iatrogenic nerve injuries. A comprehensive electronic database search was performed to identify articles reporting the prevalence of anatomical variations or morphometric data of the sciatic nerve. The data found was extracted and pooled into a meta-analysis. A total of 45 studies (n = 7068 lower limbs) were included in the meta-analysis on the sciatic nerve variations with respect to the piriformis muscle. The normal Type A variation, where the sciatic nerve exits the pelvis as a single entity below the piriformis muscle, was most common with a pooled prevalence of 85.2% (95%CI: 78.4-87.0). This was followed by Type B with a pooled prevalence of 9.8% (95%CI: 6.5-13.2), where the sciatic nerve bifurcated in the pelvis with the exiting common peroneal nerve piercing, and the tibial nerve coursing below the piriformis muscle. In morphometric analysis, we found that the pooled mean width of the sciatic nerve at the lower margin of the piriformis muscle was 15.55 mm. The pooled mean distance of sciatic nerve bifurcation from the popliteal fossa was 65.43 mm. The sciatic nerve deviates from its normal course of pelvic exit in almost 15% of cases. As such we recommend that a thorough assessment of sciatic nerve variants needs to be considered when performing procedures in the pelvic and gluteal regions in order to reduce the risk of iatrogenic injury. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1820-1827, 2016.
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Affiliation(s)
- Krzysztof A Tomaszewski
- International Evidence-Based Anatomy Working Group, Krakow, Poland. .,Department of Anatomy, Jagiellonian University Medical College, 12 Kopernika St, 31-034 Krakow, Poland.
| | - Matthew J Graves
- International Evidence-Based Anatomy Working Group, Krakow, Poland.,Department of Anatomy, Jagiellonian University Medical College, 12 Kopernika St, 31-034 Krakow, Poland
| | - Brandon Michael Henry
- International Evidence-Based Anatomy Working Group, Krakow, Poland.,Department of Anatomy, Jagiellonian University Medical College, 12 Kopernika St, 31-034 Krakow, Poland
| | - Patrick Popieluszko
- International Evidence-Based Anatomy Working Group, Krakow, Poland.,Department of Anatomy, Jagiellonian University Medical College, 12 Kopernika St, 31-034 Krakow, Poland
| | - Joyeeta Roy
- International Evidence-Based Anatomy Working Group, Krakow, Poland.,Department of Anatomy, Jagiellonian University Medical College, 12 Kopernika St, 31-034 Krakow, Poland
| | - Przemysław A Pękala
- International Evidence-Based Anatomy Working Group, Krakow, Poland.,Department of Anatomy, Jagiellonian University Medical College, 12 Kopernika St, 31-034 Krakow, Poland
| | - Wan Chin Hsieh
- International Evidence-Based Anatomy Working Group, Krakow, Poland.,First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Jens Vikse
- International Evidence-Based Anatomy Working Group, Krakow, Poland.,Department of Anatomy, Jagiellonian University Medical College, 12 Kopernika St, 31-034 Krakow, Poland
| | - Jerzy A Walocha
- International Evidence-Based Anatomy Working Group, Krakow, Poland.,Department of Anatomy, Jagiellonian University Medical College, 12 Kopernika St, 31-034 Krakow, Poland
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Levi AD, Burks SS, Anderson KD, Dididze M, Khan A, Dietrich WD. The Use of Autologous Schwann Cells to Supplement Sciatic Nerve Repair With a Large Gap: First in Human Experience. Cell Transplant 2015; 25:1395-403. [PMID: 26610173 DOI: 10.3727/096368915x690198] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Insufficient donor nerve graft material in peripheral nerve surgery remains an obstacle for successful long-distance regeneration. Schwann cells (SCs) can be isolated from adult mammalian peripheral nerve biopsies and can be grown in culture and retain their capacity to enhance peripheral nerve regeneration within tubular repair strategies in multiple animal models. Human Schwann cells (hSCs) can be isolated, expanded in number, and retain their ability to promote regeneration and myelinate axons, but have never been tested in a clinical case of peripheral nerve injury. A sural nerve biopsy and peripheral nerve tissue from the traumatized sciatic nerve stumps was obtained after Food and Drug Administration (FDA) and Institutional Review Board (IRB) approval as well as patient consent. The SCs were isolated after enzymatic digestion of the nerve and expanded with the use of heregulin β1 (0.1 µg/ml) and forskolin (15 mM). After two passages the Schwann cell isolates were combined with sural nerve grafts to repair a large sciatic nerve defect (7.5 cm) after a traumatic nerve injury. The sural nerve and the traumatized sciatic nerve ends both served as an excellent source of purified (90% and 97%, respectively) hSCs. Using ultrasound and magnetic resonance imaging (MRI) we were able to determine continuity of the nerve graft repair and the absence of tumor formation. The patient had evidence of proximal sensory recovery and definitive motor recovery distal to the repair in the distribution of the tibial and common peroneal nerve. The patient did experience an improvement in her pain scores over time. The goals of this approach were to determine the safety and clinical feasibility of implementing a new cellular repair strategy. In summary, this approach represents a novel strategy in the treatment of peripheral nerve injury and represents the first reported use of autologous cultured SCs after human peripheral nerve injury.
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Affiliation(s)
- Allan D Levi
- Department of Neurological Surgery and the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, USA
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29
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Régis J, Tuleasca C, Resseguier N, Carron R, Donnet A, Gaudart J, Levivier M. Long-term safety and efficacy of Gamma Knife surgery in classical trigeminal neuralgia: a 497-patient historical cohort study. J Neurosurg 2015; 124:1079-87. [PMID: 26339857 DOI: 10.3171/2015.2.jns142144] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Gamma Knife surgery (GKS) is one of the surgical alternatives for the treatment of drug-resistant trigeminal neuralgia (TN). This study aims to evaluate the safety and efficacy of GKS in a large population of patients with TN with very long-term clinical follow-up. METHODS Between July 1992 and November 2010, 737 patients presenting with TN were treated using GKS. Data were collected prospectively and were further retrospectively evaluated at Timone University Hospital. The frequency and severity of pain, as well as trigeminal nerve function, were evaluated before GKS and regularly thereafter. Radiosurgery using the Gamma Knife (model B, C, 4C, or Perfexion) was performed with the help of both MR and CT targeting. A single 4-mm isocenter was positioned in the cisternal portion of the trigeminal nerve at a median distance of 7.6 mm (range 4-14 mm) anterior to the emergence of the nerve (retrogasserian target). A median maximum dose of 85 Gy (range 70-90 Gy) was prescribed. RESULTS The safety and efficacy are reported for 497 patients with medically refractory classical TN who were never previously treated by GKS and had a follow-up of at least 1 year. The median age in this series was 68.3 years (range 28.1-93.2 years). The median follow-up period was 43.8 months (range 12-174.4 months). Overall, 456 patients (91.75%) were initially pain free in a median time of 10 days (range 1-180 days). Their actuarial probabilities of remaining pain free without medication at 3, 5, 7, and 10 years were 71.8%, 64.9%, 59.7%, and 45.3%, respectively. One hundred fifty-seven patients (34.4%) who were initially pain free experienced at least 1 recurrence, with a median delay of onset of 24 months (range 0.6-150.1 months). However, the actuarial rate of maintaining pain relief without further surgery was 67.8% at 10 years. The hypesthesia actuarial rate at 5 years was 20.4% and at 7 years reached 21.1%, but remained stable until 14 years with a median delay of onset of 12 months (range 1-65 months). Very bothersome facial hypesthesia was reported in only 3 patients (0.6%). CONCLUSIONS Retrogasserian GKS proved to be safe and effective in the long term and in a very large number of patients. Even if the probability of long-lasting effects may be modest compared with microvascular decompression, the rarity of complications prompts discussion of using GKS as the pragmatic surgical first- or second-intention alternative for classical TN. However, a randomized trial, or at least a case-matched control study, would be required to compare with microvascular decompression.
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Affiliation(s)
- Jean Régis
- Functional and Stereotactic Neurosurgery Service and Gamma Knife Unit, Centre Hospitalier Universitaire La Timone Assistance Publique-Hopitaux de Marseille, Université de la Méditerranée, Marseille, France
| | - Constantin Tuleasca
- Functional and Stereotactic Neurosurgery Service and Gamma Knife Unit, Centre Hospitalier Universitaire La Timone Assistance Publique-Hopitaux de Marseille, Université de la Méditerranée, Marseille, France;,Signal Processing Laboratory (LTS-5), Swiss Federal Institute of Technology, Lausanne, Switzerland;,Medical Image Analysis Laboratory, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland;,Department of Clinical Neurosciences, Neurosurgery Service and Gamma Knife Center, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland; and.,Faculty of Biology and Medicine, University of Lausanne, Switzerland
| | - Noémie Resseguier
- Department of Public Health and Medical Information, Centre Hospitalier Universitaire La Timone, Assistance Publique-Hopitaux de Marseille, France
| | - Romain Carron
- Functional and Stereotactic Neurosurgery Service and Gamma Knife Unit, Centre Hospitalier Universitaire La Timone Assistance Publique-Hopitaux de Marseille, Université de la Méditerranée, Marseille, France
| | - Anne Donnet
- Department of Neurology, Clinical Neuroscience Federation, Centre Hospitalier Universitaire La Timone Assistance Publique-Hopitaux de Marseille, France
| | - Jean Gaudart
- Department of Public Health and Medical Information, Centre Hospitalier Universitaire La Timone, Assistance Publique-Hopitaux de Marseille, France
| | - Marc Levivier
- Department of Clinical Neurosciences, Neurosurgery Service and Gamma Knife Center, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland; and.,Faculty of Biology and Medicine, University of Lausanne, Switzerland
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30
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Zilic L, Garner PE, Yu T, Roman S, Haycock JW, Wilshaw SP. An anatomical study of porcine peripheral nerve and its potential use in nerve tissue engineering. J Anat 2015. [PMID: 26200940 PMCID: PMC4560565 DOI: 10.1111/joa.12341] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Current nerve tissue engineering applications are adopting xenogeneic nerve tissue as potential nerve grafts to help aid nerve regeneration. However, there is little literature that describes the exact location, anatomy and physiology of these nerves to highlight their potential as a donor graft. The aim of this study was to identify and characterise the structural and extracellular matrix (ECM) components of porcine peripheral nerves in the hind leg. Methods included the dissection of porcine nerves, localisation, characterisation and quantification of the ECM components and identification of nerve cells. Results showed a noticeable variance between porcine and rat nerve (a commonly studied species) in terms of fascicle number. The study also revealed that when porcine peripheral nerves branch, a decrease in fascicle number and size was evident. Porcine ECM and nerve fascicles were found to be predominately comprised of collagen together with glycosaminoglycans, laminin and fibronectin. Immunolabelling for nerve growth factor receptor p75 also revealed the localisation of Schwann cells around and inside the fascicles. In conclusion, it is shown that porcine peripheral nerves possess a microstructure similar to that found in rat, and is not dissimilar to human. This finding could extend to the suggestion that due to the similarities in anatomy to human nerve, porcine nerves may have utility as a nerve graft providing guidance and support to regenerating axons.
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Affiliation(s)
- Leyla Zilic
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, UK
| | - Philippa E Garner
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Tong Yu
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, UK
| | - Sabiniano Roman
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, UK
| | - John W Haycock
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, UK
| | - Stacy-Paul Wilshaw
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK
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