Name: an anesthesia, surgery, and harvest method for the evaluation of transpedicular screws using an in vivo porcine lumbar spine model
Uploaded: 2017-05-31T12:30:00.000+00:00
Duration: 9 min 7 s
Description: Watch this Scientific Journal Video about An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model at JoVE.com

Este estudo foi apoiado por uma bolsa (CNUH-BRI-2012-02-005) financiada pelo Instituto de Pesquisa Biomédica do Hospital Nacional de Chonbuk (CNUH-BRI), República da Coréia.

O Comitê Institucional de Cuidados e Uso de Animais da Universidade Nacional de Chonbuk aprovou este estudo. O tratamento, uso e manipulação de animais seguiram todas as diretrizes e políticas. Manter a sala de operação a 24 ° C. 1. Anestesia <ol><li> Aclimatar porcos em miniatura, com idade de 12 meses, na unidade experimental por pelo menos uma semana. Realize um exame clínico que mede a freqüência respiratória, o coração e a temperatura corporal. Não alimente cada porco em miniatura por 12 h antes do procedimento de anestesia. </li><li> Injecte atropina (0,05 mg / kg) e ketamin (20 mg / kg) / xilaxina (2 mg / kg) na região lateral do músculo cervical, atrás da orelha, para a pré-medicação. </li><li> Após a sedação, aplique uma fita adesiva ao redor da base da orelha e limpe a orelha com álcool tópico. </li><li> Coloque um cateter plástico em cima da agulha na veia da orelha e remova a borracha. Confirme se o cateter está corretamente colocado. GripePegue o cateter com solução salina heparinizada e conserte com fita adesiva. </li><li> Para a intubação endotraqueal, posicione o porco em miniatura na decúbito esternal. Com a ajuda de um assistente, segure o maxilar do porco com uma funda adequada e abra a boca. <ol><li> Passe a ponta do laringoscópio na cavidade faríngea para deslocar a epiglota do paladar macio. Use a ponta da lâmina do laringoscópio para tornar visíveis os cordões vocais e avance o tubo endotraqueal para a traquéia durante a expiração. </li><li> Sinta-se para uma passagem livre de ar para a intubação adequada e verifique a ausculta do tórax para sons de respiração nos lados esquerdo e direito do porco em miniatura. </li></ol></li><li> Encha o manguito com o volume apropriado de ar do tubo endotraqueal com ar usando uma seringa de 10 mL e conserte o tubo no focinho usando fita adesiva. </li><li> Fornecer uma concentração de 2,0% de isoflurano, um anestésico por inalação para anestesia prolongada, através do endotrTubo de intubação transversal. Teste os reflexos corneano e palpebral para confirmar a anestesia e usar pomada nos olhos para evitar a secura. </li><li> Monitorize o sistema cardiovascular, o sistema respiratório e a temperatura corporal durante a anestesia pelo menos a cada 5 min até o porco em miniatura se recuperar. </li><li> 30 minutos antes da cirurgia da coluna vertebral, aplique 30 mg / kg de cefazolina IV lentamente, a 1ª geração de antibióticos de cefalosporina. </li><li> Administrar 5 a 10 mL / kg / h de solução salina quente (37 ° C) usando uma linha IV para manter a homeostase e fornecer 50 μg / kg / min de fentanil para controlar a dor. </li><li> Após a cirurgia da coluna vertebral, realizar extubação quando um forte reflexo de deglutição é aparente. </li><li> Pegue o porco em miniatura em uma sala e monitore até que ele se recupere da anestesia. Fornecer comida e água quando o porco em miniatura estiver totalmente consciente. </li><li> Aplique 3 mg / kg de antibiótico de enrofloxacina com 4,4 mg / kg de carprofeno diariamente para controle da dor durante os primeiros 3 dias. </li><li> MoniDiariamente ao porco até a remoção das suturas. </li></ol> 2. Cirurgia da coluna vertebral <ol><li> Autoclave os parafusos transpediculares e os sistemas fixadores posteriores para esterilização, seguindo as diretrizes do fabricante. </li><li> Raspe a parte de trás do porco em miniatura, a aproximadamente 10 cm do centro para a esquerda ou para a direita, usando um raspador enquanto o porco está em posição supina. Limpe a pele com solução de povidona-iodo e 70% de álcool. </li><li> Faça uma incisão longitudinal longitudinal a partir do segundo processo espinhoso da coluna lombar até a primeira crista sacral mediana usando um bisturi. Dissecar através do tecido subcutâneo e fáscia até a ponta dos processos espinhosos. </li><li> Elevar os músculos paraspinal subperiosteamente das lâminas subjacentes usando um elevador Cobb. Dissecte ao longo do processo espinhoso e a lâmina limitada às articulações facetadas. </li><li> Abra o córtex superficial do ponto de entrada (que é apenas inferior ao processo mamilítico de L3Para L5 em ambos os lados) com uma rebarba ou uma rongeur. </li><li> Insira o pino de guia em um local aberto, paralelo à placa de extremidade superior e a um ângulo de 20 ° para o processo espinhoso. Defina o ponto de partida ideal usando o braço em C ou radiografias postero-anterior / laterais portáteis. </li><li> Insira uma sonda de pedículo até 25 mm de acordo com a radiografia. Confirme a trajetória intra-ósea completa por palpação do pedículo e do corpo usando um dispositivo de sondagem do pedículo. </li><li> Insira seis parafusos pediculares no pedículo preparado de L3 a L5 até que a cabeça do parafuso esteja bem encaixada. Aponte a abertura lateral da cabeça do implante na direção desejada e alinhe a posição horizontal com a trajetória da haste. </li><li> Insira duas hastes em ambos os lados das cabeças dos parafusos do pedículo, respectivamente. Coloque a manga e a porca na cabeça do parafuso do pedículo usando uma alça universal. </li><li> Aperte suavemente a porca com uma chave de soquete reta e aperte firmemente a porca com uma chave de torque contadora. </li><li> Confirme as posições oF os parafusos pediculares usando raios X postero-anterior / laterais portáteis. NOTA: Aguarde até que o porco em miniatura acorde e verifique os padrões de marcha e a função do motor do membro traseiro para determinar se um parafuso foi mal implantado. </li><li> Irrigar o local da cirurgia com 3 L de solução salina normal usando uma seringa de irrigação com bulbo com sucção. </li><li> Coloque um dreno de silicone no local da cirurgia e tire a ponta de silicone. Feche os músculos paraspinal e subcutâneo usando suturas absorvíveis métricas. Feche a pele com suturas de nylon métricas não absorvíveis de 2.0. </li><li> Desinfecte o sítio da sutura com povidona-iodo e aplique um curativo usando gaze esterilizada e fita adesiva. </li></ol> 3. Procedimento de colheita <ol><li> Às 12 semanas pós-operatório, injete xilazina (2 mg / kg) e cetamina (10 mg / kg) na região lateral do músculo cervical, atrás da orelha, para a pré-medicação. </li><li> Após a sedação, administre 15 mg / kg de KCl diretamente na veia da orelhaCateter para a eutanásia. </li><li> Faça uma incisão longitudinal da linha média na lesão anterior da cicatriz cirúrgica. Dissecar os tecidos moles e os músculos paraspinal. </li><li> Exponha o processo espinhoso das espinhas lombares, laminas, hastes, nozes e processos transversais de L3 a L5. </li><li> Remova as porcas usando uma chave de torque com contador e hastes. Corte o espaço do disco L2-3 e o espaço do disco L5-S1 usando uma serra oscilante. </li><li> Dissecte ambos os lados da parte anterior e média da coluna L3-5 com um elevador Cobb e fórceps de torre. Após a colheita, se a coluna vertebral não pode ser testada imediatamente, envolva-a em uma gaze embebida com solução salina e guarde-a a -20 ° C. </li></ol>

<ol>
	<li>Greenfield, R. T., Grant, R. E., Bryant, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pedicle+screw+fixation+in+the+management+of+unstable+thoracolumbar+spine+injuries.">Pedicle screw fixation in the management of unstable thoracolumbar spine injuries.</a> Orthop Rev. 21 (6), 701-706 (1992).</li><li>Upasani, V. V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pedicle+screw+surface+coatings+improve+fixation+in+nonfusion+spinal+constructs.">Pedicle screw surface coatings improve fixation in nonfusion spinal constructs.</a> Spine. 34 (4), 335-343 (2009).</li><li>Halvorson, T. L., Kelley, L. A., Thomas, K. A., Whitecloud, T. S., Cook, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+bone+mineral+density+on+pedicle+screw+fixation.">Effects of bone mineral density on pedicle screw fixation.</a> Spine. 19 (21), 2415-2420 (1994).</li><li>Weinstein, J. N., Spratt, K. F., Spengler, D., Brick, C., Reid, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spinal+pedicle+fixation:+reliability+and+validity+of+roentgenogram-based+assessment+and+surgical+factors+on+successful+screw+placement.">Spinal pedicle fixation: reliability and validity of roentgenogram-based assessment and surgical factors on successful screw placement.</a> Spine. 13 (9), 1012-1018 (1988).</li><li>Fini, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biological+assessment+of+the+bone-screw+interface+after+insertion+of+uncoated+and+hydroxyapatite-coated+pedicular+screws+in+the+osteopenic+sheep.">Biological assessment of the bone-screw interface after insertion of uncoated and hydroxyapatite-coated pedicular screws in the osteopenic sheep.</a> J Biomed Mater Res A. 66 (1), 176-183 (2003).</li><li>Kim, D. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+Titanium-Coated+Pedicle+Screws:+In+Vivo+Porcine+Lumbar+Spine+Model.">Evaluation of Titanium-Coated Pedicle Screws: In Vivo Porcine Lumbar Spine Model.</a> World Neurosurg. 91, 163-171 (2016).</li><li>Upasani, V. V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pedicle+screw+surface+coatings+improve+fixation+in+nonfusion+spinal+constructs.">Pedicle screw surface coatings improve fixation in nonfusion spinal constructs.</a> Spine. 34 (4), 335-343 (2009).</li><li>Smit, T. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+a+quadrupted+as+an+in+vivo+model+for+the+study+of+the+spine-biomechanical+considrations.">The use of a quadrupted as an in vivo model for the study of the spine-biomechanical considrations.</a> Eur Spine J. 11 (2), 137-144 (2002).</li><li>Aldini, N. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pedicular+fixation+in+the+osteoporotic+spine:+a+pilot+in+vivo+study+on+long-term+ovariectomized+sheep.">Pedicular fixation in the osteoporotic spine: a pilot in vivo study on long-term ovariectomized sheep.</a> J Orthop Res. 20 (6), 1217-1224 (2002).</li><li>Fini, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biological+assessment+of+the+bone-screw+interface+after+insertion+of+uncoated+and+hydroxyapatite-coated+pedicular+screws+in+the+osteopenic+sheep.">Biological assessment of the bone-screw interface after insertion of uncoated and hydroxyapatite-coated pedicular screws in the osteopenic sheep.</a> J Biomed Mater Res A. 66 (1), 176-183 (2003).</li><li>Branemark, R., Ohrnell, L. O., Skalak, R., Carlsson, L., Branemark, P. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biomechanical+characterization+of+osseointegration:+an+experimental+in+vivo+investigation+in+the+beagle+dog.">Biomechanical characterization of osseointegration: an experimental in vivo investigation in the beagle dog.</a> J Orthop Res. 16 (1), 61-69 (1998).</li><li>McLain, R. F., Yerby, S. A., Moseley, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+morphometry+of+L4+vertebrae:+comparison+of+large+animal+models+for+the+human+lumbar+spine.">Comparative morphometry of L4 vertebrae: comparison of large animal models for the human lumbar spine.</a> Spine. 27 (8), E200-E206 (2002).</li><li>Giavaresi, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+preclinical+evaluation+of+the+influence+of+osteoporosis+on+the+anchorage+of+different+pedicle+screw+designs.">In vivo preclinical evaluation of the influence of osteoporosis on the anchorage of different pedicle screw designs.</a> Eur Spine J. 20 (8), 1289-1296 (2011).</li><li>Hasegawa, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydroxyapatite-coating+of+pedicle+screws+improves+resistance+against+pull-out+force+in+the+osteoporotic+canine+lumbar+spine+model:+a+pilot+study.">Hydroxyapatite-coating of pedicle screws improves resistance against pull-out force in the osteoporotic canine lumbar spine model: a pilot study.</a> Spine J. 5 (3), 239-243 (2005).</li><li>Smorgick, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single-+versus+multilevel+fusion+for+single-level+degenerative+spondylolisthesis+and+multilevel+lumbar+stenosis:+four-year+results+of+the+spine+patient+outcomes+research+trial.">Single- versus multilevel fusion for single-level degenerative spondylolisthesis and multilevel lumbar stenosis: four-year results of the spine patient outcomes research trial.</a> Spine. 38 (10), 797-805 (2013).</li><li>Busscher, I., Ploegmakers, J. J., Verkerke, G. J., Veldhuizen, A. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+anatomical+dimensions+of+the+complete+human+and+porcine+spine.">Comparative anatomical dimensions of the complete human and porcine spine.</a> Eur Spine J. 19 (7), 1104-1114 (2010).</li></ol>

Os autores não têm nada relacionado a este artigo para divulgar.

A avaliação dos parafusos transpediculares na espinha porcina requer muito tempo e esforço. Primeiro, o porco em miniatura é um animal grande. Para cuidados com animais e anestesia, o pesquisador precisa de um protocolo especializado. Em segundo lugar, a cirurgia deve manter um ambiente semelhante ao da cirurgia humana. O objetivo da avaliação dos parafusos pedicais na espinha porcina é desenvolver um parafuso eficiente que possa ser aplicado aos seres humanos. Em terceiro lugar, avaliar a estabilidade a longo pr...

Transpedicular screw fixation is a gold-standard treatment for degenerative lumbar spine and bursting fracture because it involves three columns of the spine and achieves stabilization1,2. However, most patients who undergo such surgery also have osteoporosis3,4. Many studies have evaluated the fixation strength and the osseointegration status of transpedicular screws, because the loosening of pedicle screws currently in use has been reported in patients with osteoporosis5,6.
The porcine spine is similar to the human spine in terms of size. It is less expensive compared to a primate model7. Furthermore, an in vivo mechanical study has demonstrated that the quadruped porcine spine is essentially loaded in the same way as that of the human spine8, which is why many researchers use porcine spines for studies on the prevention of pedicle screw loosening. However, it takes several months to study pedicle screws in the porcine spine because identifying the long-term stability of pedicle screws takes times. In order to compare different types of screws in the vertebral body, it is necessary to insert the screws in similar positions. Therefore, researchers should be well-acquainted with proper anesthesia techniques, standardized surgical protocols, and harvest procedures before performing any experiments. Here, we describe a detailed method for anesthesia, surgery, and harvest for the evaluation of pedicle screw fixation using a porcine spine model, including ex vivo imaging, histology, and strength testing.

<table><tbody><tr><td>Miniature pig</td><td>OrientBio</td><td></td><td></td></tr><tr><td>Atropine</td><td>Jeil pharmaceutical</td><td>A04900241</td><td>Anesthesia</td></tr><tr><td>Over-the needle plastic catheter</td><td>BD</td><td>REF382412</td><td>Maintenance of IV line</td></tr><tr><td>Ketamine</td><td>Yuhan</td><td>A04502441</td><td>Anesthesia</td></tr><tr><td>Xylazine</td><td>Bayer Korea</td><td>A00800071</td><td>Anesthesia</td></tr><tr><td>Laryngoscope</td><td>Karl storz</td><td></td><td>Intubation</td></tr><tr><td>Endotracheal tube</td><td>Covidien</td><td></td><td>Intubation</td></tr><tr><td>Isoflurane</td><td>JW pharmaceutical Co</td><td>A02104781</td><td>Anesthesia</td></tr><tr><td>Eye ointment</td><td>Hanlim pharma</td><td>A37851721</td><td>Protection of pig&#039;s eye</td></tr><tr><td>Cefazolin</td><td>Donga pharma</td><td>A01503951</td><td>Antibiotics</td></tr><tr><td>Saline</td><td>JW pharmaceutical Co</td><td>A02151392</td><td>Maintenance of fluid homeostasis</td></tr><tr><td>Fentanyl</td><td>Hana pharm</td><td>C03200032</td><td>Pain control</td></tr><tr><td>Enrofloxacin</td><td>Bayer</td><td>93106-60-6&amp;nbsp;</td><td>Antibiotics</td></tr><tr><td>Morphine</td><td>Myungmoon pharma</td><td>C03700091</td><td>Pain control</td></tr><tr><td>Meloxicam</td><td>Boehringer Ingelheim</td><td>A07600711</td><td>Antibiotics</td></tr><tr><td>Povidone-iodine</td><td>Hyundai pharma</td><td></td><td>Wound dressing</td></tr><tr><td>Scalpel blade size 15</td><td>Braun</td><td>&amp;nbsp;I1 BB515</td><td>Skin incision</td></tr><tr><td>Cobb elevator</td><td>Codman</td><td>65-2546</td><td>Dissection of muscle</td></tr><tr><td>Burr</td><td>Medtronic</td><td></td><td>Making of starting point of screw</td></tr><tr><td>Rongeur</td><td>Aesculap</td><td>FO515R</td><td>Making of starting point of screw</td></tr><tr><td>Guide pin (K-wire)</td><td>CE</td><td>01067803</td><td>Guidance of screw trajectory</td></tr><tr><td>C-arm</td><td>GE</td><td>OEC 9800 plus</td><td>Guidance of screw trajectory</td></tr><tr><td>Portable X-ray</td><td>Siemens</td><td>Mobile XP hybrid</td><td>Guidance of screw trajectory</td></tr><tr><td>Pedicle probe</td><td>OtisBiotech</td><td>SPI-02-01</td><td>Guidance of screw trajectory</td></tr><tr><td>Pedicle sounding device</td><td>OtisBiotech</td><td>SPI-03-01</td><td>Guidance of screw trajectory</td></tr><tr><td>Pedicle screw</td><td>OtisBiotech</td><td>MS-40025</td><td></td></tr><tr><td>Posterior fixator systems</td><td>OtisBiotech</td><td></td><td></td></tr><tr><td>Rod&amp;nbsp;</td><td>OtisBiotech</td><td>ROD-60140</td><td>Rigid fixation between screws</td></tr><tr><td>Universal handle</td><td>OtisBiotech</td><td>SPI-08-01</td><td>To fix the screws to the rod</td></tr><tr><td>Straight socket wrench</td><td>OtisBiotech</td><td>SPI-06-01</td><td>To fix the screws to the rod</td></tr><tr><td>counter torque wrench</td><td>OtisBiotech</td><td>SPI-07-01</td><td>To fix the screws to the rod</td></tr><tr><td>Bulb irrigation syringe</td><td>Hyupsug medical</td><td>HS-IR-140</td><td>Irrigation</td></tr><tr><td>Silicone drain</td><td>Sewon medical</td><td>2205-006</td><td>To drain the fluid at the surgical site</td></tr><tr><td>3.0 metric absorbable suture</td><td>Ethicon</td><td>BA1673H</td><td>Muscle suture</td></tr><tr><td>2.0 metric nonabsorbable nylon suture</td><td>Ethicon</td><td>W1626T</td><td>Skin suture</td></tr><tr><td>Gauze</td><td>Kingphar Korea</td><td>KP120-06</td><td></td></tr><tr><td>Pentobarbital</td><td>Hanlim pharma</td><td>645301221</td><td>Euthanasia</td></tr><tr><td>Oscillating saw</td><td>Zimmer</td><td></td><td>Harvest spine</td></tr><tr><td>Tower forceps</td><td>Aesculap</td><td>BF461R</td><td>Harvest spine</td></tr></tbody></table>

an anesthesia, surgery, and harvest method for the evaluation of transpedicular screws using an in vivo porcine lumbar spine model

A fixação do parafuso pedículo é o padrão-ouro para o tratamento de doenças da coluna vertebral. No entanto, muitos estudos relataram a questão do afrouxamento dos parafusos pedicais após a cirurgia da coluna vertebral, o que é uma preocupação séria. Para resolver este problema, diversos tipos de parafusos pedicais foram examinados para identificar aqueles com boa força de fixação e osseointegração no osso da coluna vertebral. A espinha porcina é uma boa alternativa para a coluna vertebral humana na avaliação de parafusos pediculares devido ao tamanho anatômico, características mecânicas e custo. Embora vários estudos tenham relatado que os parafusos pediculares são eficientes no modelo porcino, nenhum estudo descreveu protocolos detalhados para a avaliação de um parafuso de pedículo usando o modelo porcino. Aqui, descrevemos um método detalhado para avaliar os parafusos transpediculares usando um modelo de coluna espinhal porcino in vivo . Os detalhes técnicos para anestesia, cirurgia de coluna e colheita fornecidos aqui facilitarão com a avaliação do tModelo de fixação de parafuso ranspedicular.

Um protocolo detalhado para anestesia, cirurgia e colheita para avaliação de parafusos transpediculares usando um modelo de coluna espinhal porcino in vivo é descrito aqui. Este protocolo é adequado para uma série de análises a jusante, incluindo testes mecânicos ( Figura 1 ), avaliação quantitativa de micro-CT ( Figura 2 ) e histologia ( Figura 3 ). Testes mecânicos representativos ( Figura 1 ) mostra...

Watch this Scientific Journal Video about An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model at JoVE.com

An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model

Aqui, apresentamos um método para avaliar os parafusos transpediculares utilizando um modelo de coluna lombar porcino in vivo .

Método de anestesia, cirurgia e colheita para avaliação de parafusos transpediculares usando um In Vivo Modelo de espinha lombar porcina

Pedicle screw fixation is the gold standard for the treatment of spinal diseases. However, many studies have reported the issue of loosening pedicle ...

an-anesthesia-surgery-harvest-method-for-evaluation-transpedicular

Research

Education

JoVE Core

JoVE Journal

Pharmacology

Medicine

Unit 1

An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model

Local Anesthetics

SCIENTISTS IN ACTION

7.6K visualizações.  Chonbuk National University School of Medicine, Chonbuk National University Hospital.  Aqui, apresentamos um método para avaliar os parafusos transpediculares utilizando um modelo de coluna lombar porcino in vivo . 

Vídeo: An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model

In vivo Imaging of the Mouse Spinal Cord Using Two-photon Microscopy

In vivo imaging using two-photon microscopy 1 in mice that have been genetically engineered to express fluorescent proteins in specific cell types 2-3 has significantly broadened our knowledge of physiological and pathological processes in numerous tissues in vivo 4-7. In studies of the central nervous system (CNS), there has been a broad application of in vivo imaging in the brain, which has produced a plethora of novel and often unexpected findings about the behavior of cells such as neurons, astrocytes, microglia, under physiological or pathological conditions 8-17. However, mostly technical complications have limited the implementation of in vivo imaging in studies of the living mouse spinal cord. In particular, the anatomical proximity of the spinal cord to the lungs and heart generates significant movement artifact that makes imaging the living spinal cord a challenging task.
We developed a novel method that overcomes the inherent limitations of spinal cord imaging by stabilizing the spinal column, reducing respiratory-induced movements and thereby facilitating the use of two-photon microscopy to image the mouse spinal cord in vivo. This is achieved by combining a customized spinal stabilization device with a method of deep anesthesia, resulting in a significant reduction of respiratory-induced movements. This video protocol shows how to expose a small area of the living spinal cord that can be maintained under stable physiological conditions over extended periods of time by keeping tissue injury and bleeding to a minimum. Representative raw images acquired in vivo detail in high resolution the close relationship between microglia and the vasculature. A timelapse sequence shows the dynamic behavior of microglial processes in the living mouse spinal cord. Moreover, a continuous scan of the same z-frame demonstrates the outstanding stability that this method can achieve to generate stacks of images and/or timelapse movies that do not require image alignment post-acquisition. Finally, we show how this method can be used to revisit and reimage the same area of the spinal cord at later timepoints, allowing for longitudinal studies of ongoing physiological or pathological processes in vivo.

In vivo Imaging of the Mouse Spinal Cord Using Two-photon Microscopy

A minimally invasive protocol to stabilize the mouse spinal column and perform repetitive in vivo spinal cord imaging using two-photon microscopy is described. This method combines a spinal stabilization device and an anesthetic regimen to minimize respiratory-induced movements and produce raw imaging data that require no alignment or other post-processing.

Em Imaging vivo do Cordão do rato Spinal Usando Two-photon Microscopia

In vivo imaging using two-photon microscopy 1 in mice that have been genetically engineered to express fluorescent proteins in specific cell types 2-3 has ...

Neurociência

A Procedure for Implanting a Spinal Chamber for Longitudinal In Vivo Imaging of the Mouse Spinal Cord

Studies in the mammalian neocortex have enabled unprecedented resolution of cortical structure, activity, and response to neurodegenerative insults by repeated, time-lapse in vivo imaging in live rodents. These studies were made possible by straightforward surgical procedures, which enabled optical access for a prolonged period of time without repeat surgical procedures. In contrast, analogous studies of the spinal cord have been previously limited to only a few imaging sessions, each of which required an invasive surgery. As previously described, we have developed a spinal chamber that enables continuous optical access for upwards of 8 weeks, preserves mechanical stability of the spinal column, is easily stabilized externally during imaging, and requires only a single surgery. Here, the design of the spinal chamber with its associated surgical implements is reviewed and the surgical procedure is demonstrated in detail. Briefly, this video will demonstrate the preparation of the surgical area and mouse for surgery, exposure of the spinal vertebra and appropriate tissue debridement, the delivery of the implant and vertebral clamping, the completion of the chamber, the removal of the delivery system, sealing of the skin, and finally, post-operative care. The procedure for chronic in vivo imaging using nonlinear microscopy will also be demonstrated. Finally, outcomes, limitations, typical variability, and a guide for troubleshooting are discussed.

A Procedure for Implanting a Spinal Chamber for Longitudinal In Vivo Imaging of the Mouse Spinal Cord

In this video, we describe a procedure for implanting a chronic optical imaging chamber over the dorsal spinal cord of a live mouse. The chamber, surgical procedure, and chronic imaging are reviewed and demonstrated.

Um Processo de Implantação de uma Câmara Spinal para Longitudinal<em&gt; In Vivo</em&gt; Criação de Imagens do Cordão do rato Spinal

Studies in the mammalian neocortex have enabled unprecedented resolution of cortical structure, activity, and response to neurodegenerative insults by ...

Laminotomy for Lumbar Dorsal Root Ganglion Access and Injection in Swine

Dorsal root ganglia (DRG) are anatomically well defined structures that contain all primary sensory neurons below the head. This fact makes DRG attractive targets for injection of novel therapeutics aimed at treating chronic pain. In small animal models, laminectomy has been used to facilitate DRG injection because it involves surgical removal of the vertebral bone surrounding each DRG. We demonstrate a technique for intraganglionic injection of lumbar DRG in a large animal species, namely, swine. Laminotomy is performed to allow direct access to DRG using standard neurosurgical techniques, instruments, and materials. Compared with more extensive bone removal via laminectomy, we implement laminotomy to conserve spinal anatomy while achieving sufficient DRG access. Intraoperative progress of DRG injection is monitored using a non-toxic dye. Following euthanasia on post-operative day 21, the success of injection is determined by histology for intraganglionic distribution of 4&#39;,6-diamidino-2-phenylindole (DAPI). We inject a biologically inactive solution to demonstrate the protocol. This method could be applied in future preclinical studies to target therapeutic solutions to DRG. Our methodology should facilitate testing the translatability of intraganglionic small animal paradigms in a large animal species. Additionally, this protocol may serve as a key resource for those planning preclinical studies of DRG injection in swine.

We describe a method for laminotomy in swine that provides access to lumbar dorsal root ganglia (DRG) for intraganglionic injection. Injection progress is monitored intraoperatively and histologically confirmed up to 21 days after surgery. This protocol could be used for future preclinical studies involving DRG injection.

Laminotomy para acesso de gânglio lombar Dorsal raiz e injeção em suínos

Dorsal root ganglia (DRG) are anatomically well defined structures that contain all primary sensory neurons below the head. This fact makes DRG attractive ...

Laminectomy and Spinal Cord Window Implantation in the Mouse

This protocol describes a method for spinal cord laminectomy and glass window implantation for in vivo imaging of the mouse spinal cord. An integrated digital vaporizer is utilized to achieve a stable plane of anesthesia at a low-flow rate of isoflurane. A single vertebral spine is removed, and a commercially available cover-glass is overlaid on a thin agarose bed. A 3D-printed plastic backplate is then affixed to the adjacent vertebral spines using tissue adhesive and dental cement. A stabilization platform is used to reduce motion artifact from respiration and heartbeat. This rapid and clamp-free method is well-suited for acute multi-photon fluorescence microscopy. Representative data are included for an application of this technique to two-photon microscopy of the spinal cord vasculature in transgenic mice expressing eGFP:Claudin-5 &#8212; a tight junction protein.

This protocol describes implantation of a glass window onto the spinal cord of a mouse to facilitate visualization by intravital microscopy.

Implante de janela de laminectomia e medula espinhal no mouse

This protocol describes a method for spinal cord laminectomy and glass window implantation for in vivo imaging of the mouse spinal cord. An integrated ...

In Vivo Mouse Model of Spinal Implant Infection

Spine implant infections portend poor outcomes as diagnosis is challenging and surgical eradication is at odds with mechanical spinal stability. The purpose of this method is to describe a novel mouse model of spinal implant infection (SII) that was created to provide an inexpensive, rapid, and accurate in vivo tool to test potential therapeutics and treatment strategies for spinal implant infections.
In this method, we present a model of posterior-approach spinal surgery in which a stainless-steel k-wire is transfixed into the L4 spinous process of 12-week old C57BL/6J wild-type mice and inoculated with 1 x 103 CFU of a bioluminescent strain of Staphylococcus aureus Xen36 bacteria. Mice are then longitudinally imaged for bioluminescence in vivo on post-operative days 0, 1, 3, 5, 7, 10, 14, 18, 21, 25, 28, and 35. Bioluminescence imaging (BLI) signals from a standardized field of view are quantified to measure in vivo bacterial burden.
To quantify bacteria adhering to implants and peri-implant tissue, mice are euthanized and the implant and surrounding soft tissue are harvested. Bacteria are detached from the implant by sonication, cultured overnight and then colony forming units (CFUs) are counted. The results acquired from this method include longitudinal bacterial counts as measured by in vivo S. aureus bioluminescence (mean maximum flux) and CFU counts following euthanasia.
While prior animal models of instrumented spine infection have involved invasive, ex vivo tissue analysis, the mouse model of SII presented in this paper leverages noninvasive, real time in vivo optical imaging of bioluminescent bacteria to replace static tissue study. Applications of the model are broad and may include utilizing alternative bioluminescent bacterial strains, incorporating other types of genetically engineered mice to contemporaneously study host immune response, and evaluating current or investigating new diagnostic and therapeutic modalities such as antibiotics or implant coatings.

The protocol describes a novel in vivo mouse model of spinal implant infection where a stainless-steel k-wire implant is infected with bioluminescent Staphylococcus aureus Xen36. Bacterial burden is monitored longitudinally with bioluminescent imaging and confirmed with colony forming unit counts after euthanasia.

Modelo in vivo de infecção de implante espinhal em camundongos

Spine implant infections portend poor outcomes as diagnosis is challenging and surgical eradication is at odds with mechanical spinal stability. The ...

Medicina

Real-Time Assessment of Spinal Cord Microperfusion in a Porcine Model of Ischemia/Reperfusion

Spinal cord injury is a devastating complication of aortic repair. Despite developments for the prevention and treatment of spinal cord injury, its incidence is still considerably high and therefore, influences patient outcome. Microcirculation plays a key role in tissue perfusion and oxygen supply and is often dissociated from macrohemodynamics. Thus, direct evaluation of spinal cord microcirculation is essential for the development of microcirculation-targeted therapies and the evaluation of existing approaches in regard to spinal cord microcirculation. However, most of the methods do not provide real-time assessment of spinal cord microcirculation. The aim of this study is to describe a standardized protocol for real-time spinal cord microcirculatory evaluation using laser-Doppler needle probes directly inserted in the spinal cord. We used a porcine model of ischemia/reperfusion to induce deterioration of the spinal cord microcirculation. In addition, a fluorescent microsphere injection technique was used. Initially, animals were anesthetized and mechanically ventilated. Thereafter, laser-Doppler needle probe insertion was performed, followed by the placement of cerebrospinal fluid drainage. A median sternotomy was performed for exposure of the descending aorta to perform aortic cross-clamping. Ischemia/reperfusion was induced by supra-celiac aortic cross-clamping for a total of 48 min, followed by reperfusion and hemodynamic stabilization. Laser-Doppler Flux was performed in parallel with macrohemodynamic evaluation. In addition, automated cerebrospinal fluid drainage was used to maintain a stable cerebrospinal pressure. After completion of the protocol, animals were sacrificed, and the spinal cord was harvested for histopathological and microsphere analysis. The protocol reveals the feasibility of spinal cord microperfusion measurements using laser-Doppler probes and shows a marked decrease during ischemia as well as recovery after reperfusion. Results showed comparable behavior to fluorescent microsphere evaluation. In conclusion, this new protocol might provide a useful large animal model for future studies using real-time spinal cord microperfusion assessment in ischemia/reperfusion conditions.

Spinal cord microcirculation plays a pivotal role in spinal cord injury. Most methods do not allow real-time assessment of spinal cord microcirculation, which is essential for the development of microcirculation-targeted therapies. Here, we propose a protocol using Laser-Doppler-Flow Needle probes in a large animal model of ischemia/reperfusion.

Avaliação em tempo real da microperfusão da medula espinhal em um modelo suíno de isquemia/reperfusão

Spinal cord injury is a devastating complication of aortic repair. Despite developments for the prevention and treatment of spinal cord injury, its ...

Surgical Technique for Lumbar Spinal Catheter Insertion in Pigs Enabling Continuous Access to the Thecal Sac in a Terminal Setup

Pigs are increasingly used as a large animal model for pharmacologic CNS research due to the anatomical and physiological similarities between the porcine and human central nervous systems (CNS). However, accessing the cerebrospinal fluid (CSF) in larger pig breeds by conventional lumbar puncture techniques can be challenging due to an oblique orientation of the spinal spinous processes and a limited interlaminar space. Accordingly, an open surgical procedure for inserting a lumbar spinal catheter for continuous CSF sampling at the L4/L5 level in pigs is thoroughly described in this work. After positioning the pig and identifying the anatomical landmarks, a dorsal midline surgical incision is made to expose the spinous processes. By advancing the introducer needle, the spinal catheter is inserted inside the thecal sac of the spinal canal while leaving the bone structures of the spine intact. This method allows continuous infusion into or sampling from the porcine thecal sac with minimal bleeding or CSF leakage. The procedure is simple, time-efficient, and reproducible across different experimental setups, offering significant potential for various pre-clinical studies, including pharmacokinetic research, surgical training, and spinal cord injury models.

We present a technique for inserting a lumbar spinal catheter at the L4-L5 level in a 3-month-old Danish Landrace pig as part of a terminal research protocol, enabling continuous infusion or CSF sampling from the thecal sac.

Técnica cirúrgica para inserção de cateter espinhal lombar em suínos permitindo acesso contínuo ao saco tecal em uma configuração terminal

Pigs are increasingly used as a large animal model for pharmacologic CNS research due to the anatomical and physiological similarities between the porcine ...

A Mouse Model of Lumbar Spine Instability

Intervertebral disc degeneration (IDD) is a common pathological change leading to low back pain. Appropriate animal models are desired for understanding the pathological processes and evaluating new drugs. Here, we introduced a surgically induced lumbar spine instability (LSI) mouse model that develops IDD starting from 1 week post operation. In detail, the mouse under anesthesia was operated by low back skin incision, L3&#8211;L5 spinous processes exposure, detachment of paraspinous muscles, resection of processes and ligaments, and skin closure. L4&#8211;L5 IVDs were chosen for the observation. The LSI model develops lumbar IDD by porosity and hypertrophy in endplates at an early stage, decrease in intervertebral disc volume, shrinkage in nucleus pulposus at an intermediate stage, and bone loss in lumbar vertebrae (L5) at a later stage. The LSI mouse model has the advantages of strong operability, no requirement of special equipment, reproducibility, inexpensive, and relatively short period of IDD development. However, LSI operation is still a trauma that causes inflammation within the first week post operation. Thus, this animal model is suitable for study of lumbar IDD.

We developed a lumbar intervertebral disc degeneration mouse model by resection of L3&#8211;L5 spinous processes along with supra- and inter-spinous ligaments and detachment of paraspinous muscles.

Um modelo de mouse de instabilidade lombar

Intervertebral disc degeneration (IDD) is a common pathological change leading to low back pain. Appropriate animal models are desired for understanding ...

Biologia

Pedicle Screw Placement Using an Augmented Reality Head-Mounted Display in a Porcine Model

This protocol helps assess the accuracy and workflow of an augmented reality (AR) hybrid navigation system using the Magic Leap head-mounted display (HMD) for minimally invasive pedicle screw placement. The cadaveric porcine specimens were placed on a surgical table and draped with sterile covers. The levels of interest were identified using fluoroscopy, and a dynamic reference frame was attached to the spinous process of a vertebra in the region of interest. Cone beam computerized tomography (CBCT) was performed, and a 3D rendering was automatically generated, which was used for the subsequent planning of the pedicle screw placements. Each surgeon was fitted with an HMD that was individually eye-calibrated and connected to the spinal navigation system.
Navigated instruments, tracked by the navigation system and displayed in 2D and 3D in the HMD, were used for 33 pedicle cannulations, each with a diameter of 4.5 mm. Postprocedural CBCT scans were assessed by an independent reviewer to measure the technical (deviation from the planned path) and clinical (Gertzbein grade) accuracy of each cannulation. The navigation time for each cannulation was measured. The technical accuracy was 1.0 mm &#177; 0.5 mm at the entry point and 0.8 mm &#177; 0.1 mm at the target. The angular deviation was 1.5&#176; &#177; 0.6&#176;, and the mean insertion time per cannulation was 141 s &#177; 71 s. The clinical accuracy was 100% according to the Gertzbein grading scale (32 grade 0; 1 grade 1). When used for minimally invasive pedicle cannulations in a porcine model, submillimeter technical accuracy and 100% clinical accuracy could be achieved with this protocol.

The augmented reality head-mounted display, Magic Leap, was used in combination with a conventional navigation system to place pedicle screws in a porcine model by adhering to a novel workflow. With a median insertion time of &lt;2.5 min, submillimeter technical accuracy and 100% clinical accuracy were achieved according to Gertzbein.

Colocação de parafuso pedicular usando um display de realidade aumentada montado na cabeça em um modelo suíno

This protocol helps assess the accuracy and workflow of an augmented reality (AR) hybrid navigation system using the Magic Leap head-mounted display (HMD) ...

Laser Doppler Needle Probe Insertion: A Technique for Real-time Quantification of Blood Flow within the Spinal Cord in a Porcine Model

Source: Behem, C. R. et al., <a href="https://www.jove.com/v/62047">Real-Time Assessment of Spinal Cord Microperfusion in a Porcine Model of Ischemia/Reperfusion.</a> J. Vis. Exp. (2020).
This video demonstrates the placement of a laser Doppler needle probe in the spinal cord of a porcine model. This helps in the continuous quantification of blood supply to the spinal cord, an important assessment in spinal cord injury.

Inserção de sonda de agulha Doppler a laser: uma técnica para quantificação em tempo real do fluxo sanguíneo na medula espinhal em um modelo suíno

Source: Behem, C. R. et al., Real-Time Assessment of Spinal Cord Microperfusion in a Porcine Model of Ischemia/Reperfusion. J. Vis. Exp. (2020).
This ...