Surgical complications associated with hemilaminectomy and intervertebral disc fenestration: prospective study of 64 dogs / Complicações associadas à hemilaminectomia toracolombar e fenestração de disco intervertebral: estudo prospectivo em 64 cães

Hemilaminectomy and intervertebral disc fenestration are commonly used to treat intervertebral disc extrusion (IVDE); however, they are associated with surgical complications. Sixty-four dogs were assessed during the intraoperative, immediate postoperative, and late postoperative periods to evaluate complications resulting from these surgical procedures. During this study, 15.62% (n=10) of the dogs presented with complications during at least one of the evaluations. Iatrogenic rhizotomy, access to the spinal canal contralateral to the lesion, and cardiorespiratory arrest were observed intraoperatively. Abdominal wall flaccidity, neurological worsening, hematoma, dehiscence, and superficial wound infections were observed during the immediate postoperative period. Adverse reactions to the surgical thread, scar adhesion, and superficial wound infection were the most frequent complications during the late postoperative period. Dogs that undergo hemilaminectomy and intervertebral disc fenestration because of IVDE may experience complications during the intraoperative, immediate postoperative, and late postoperative periods. However, these complications are often transitory and rarely cause death.

A hemilaminectomia e a fenestração do disco intervertebral são os procedimentos cirúrgicos geralmente empregados no tratamento da extrusão do disco intervertebral (EDIV), os quais podem desencadear complicações cirúrgicas. Foram avaliadas complicações em 64 cães nos períodos intra e pós-operatório imediato e tardio. Dos pacientes incluídos no estudo, 15,62% (n=10) apresentaram alguma ocorrência em pelo menos uma das etapas avaliadas. Das complicações, no período intraoperatório foram observadas rizotomia iatrogênica, abertura do canal vertebral contralateral e parada cardio-respiratória. No pós-operatório imediato foram verificadas a flacidez da parede abdominal lateral, piora neurológica, hematoma, deiscência de ferida cirúrgica e infecção superficial da ferida de pele. No pós-operatório tardio foram verificadas reação ao fio cirúrgico, aderência cicatricial e flacidez da parede abdominal lateral como problemas mais frequentes. Conclui-se que cães submetidos à hemilaminectomia e fenestração do disco intervertebral envolvido em decorrência da EDIV podem apresentar complicações nos períodos intraoperatório, pós-operatório imediato e tardio, sendo transitórias e com mínimas chances de ocasionar óbito.

Biomechanical study of partial lateral corpectomy with or without an association with pediculectomy and hemilaminectomy in canine specimens / Estudo biomecânico de corpectomia lateral parcial com ou sem associação com pediculectomia e hemilaminectomia em espécimes caninos

The present objective was to increase the number of biomechanical cycles performed using non-chondrodystrophic dog specimens, based on the study by Araújo (2017), comparing partial lateral corpectomy (PLC) alone, corpectomy and pediculectomy, and PLC associated with pediculectomy and hemilaminectomy to determine if there are significant differences between them regarding deformation versus applied force. Groups were divided as: control (G1), corpectomy (G2), corpectomy +pediculectomy (G3), and corpectomy + pediculectomy + hemilaminectomy (G4). The level of displacement versus force was observed during axial compression, flexion, extension, right and left lateral bending, and right and left axial rotation. Significant differences were observed between groups for flexion, extension, right and left axial rotation, and left lateral bending, whereas there was no difference for axial compression and right lateral bending. PLC and PLC with pediculectomy had significant differences in flexion and in extension, similar to PLC associated with pediculectomy and with hemilaminectomy in right and left axial rotation, flexion, extension, and right lateral bending.

O presente objetivo foi, a partir de grupos de espécimes caninas não condrodistróficas, aumentar o número de ciclos biomecânicos realizados, com base no estudo de Araújo (2017), comparando-se corpectomia parcial lateral (CPL) isolada, corpectomia e pediculectomia, à CPL associada à pediculectomia e à hemilaminectomia, no intuito de determinar se há diferenças significativas entre eles quanto à deformação versus à força aplicada. Os grupos foram divididos em: controle (G1), corpectomia (G2), corpectomia + pediculectomia (G3) e corpectomia + pediculectomia + hemilaminectomia (G4). O nível de deslocamento versus a força foi observado durante a compressão axial, a flexão, a extensão, a flexão lateral direita e esquerda e a rotação axial direita e esquerda. Observaram-se diferenças significativas entre os grupos para flexão, extensão, rotação axial direita e esquerda e flexão lateral esquerda, ao passo que, na compressão axial e na flexão lateral direita, não houve diferença. CPL e CPL com pediculectomia tiveram diferenças significativas na flexão e na extensão, semelhantemente à CPL associada à pediculectomia e à hemilaminectomia nos movimentos de rotação axial direita e esquerda, flexão, extensão e flexão lateral direita.

Focal spinal hyperesthesia as a prognostic factor in paraplegic dogs without deep pain perception / Hiperestesia espinhal focal como fator prognóstico em cães paraplégicos sem percepção de dor profunda

Intervertebral disc extrusion (IVDE) is the most common cause of spinal cord compression in dogs, whose prognosis is variable and depends on several factors, with deep pain perception (DPP) being the main parameter used. Investigations of new prognostic factors are studied to assist in the estimation of functional recovery. Thus, this study aimed to evaluate whether spinal hyperesthesia (SH) at the compression site can be used as a prognostic factor for the functional recovery of dogs with acute IVDE (Hansen type I), without DPP being subjected to thoracolumbar hemilaminectomy. Decompression surgery was performed on the same day or the day after admission. The duration of the loss of DPP until surgery performance ranged from 1 to 60 days, with a median of 4.5 days for the group of dogs with SH and 5.5 days for those without SH. Among the 68 dogs included in this retrospective study, 73.5% (50/68) showed SH, and 26.5% (18/68) were not identified. Recovery was satisfactory in 60% (30/50) of dogs with SH and in 27.7% (5/18) of dogs without SH, demonstrating that paraplegic dogs without DPP but with SH were 3.9 times more likely to recover when compared to dogs in the same condition, but with no SH. No studies have evaluated SH by palpation of the spine as a prognostic factor, which reinforces the relevance of the present study. The results of this study imply that SH in paraplegic dogs affected by thoracolumbar IVDE, without the presence of DPP, can be used as a possible prognostic indicator of functional recovery.

A extrusão do disco intervertebral (EDIV) é a causa mais comum de lesão compressiva na medula espinhal de cães, cujo prognóstico é variável e depende de diversos fatores, sendo a percepção de dor profunda (PDP) o principal parâmetro utilizado. Pesquisas de novos fatores prognósticos são estudados com intuito de auxiliar na estimativa mais precisa de recuperação funcional. Com isso, o objetivo do estudo foi avaliar se a hiperestesia espinhal (HE) no local da compressão, pode ser utilizada como um fator prognóstico para recuperação funcional de cães com extrusão aguda do disco intervertebral (Hansen tipo I), sem a presença de PDP submetidos a hemilaminectomia toracolombar. A cirurgia descompressiva ocorreu no mesmo dia ou no dia seguinte ao atendimento. A duração da perda de dor profunda até a realização da cirurgia variou de 1 a 60 dias, com uma mediana de 4,5 dias para o grupo de cães com e 5,5 dias para aqueles sem hiperestesia espinhal. Dos 68 cães incluídos nesse estudo retrospectivo, 73,5% (50/68) apresentavam HE e, em 26,5% (18/68) a dor não foi identificada. A recuperação foi satisfatória nos cães com HE em 60% (30/50) e, sem HE, em 27,7% (5/18) dos casos, demonstrando que os cães paraplégicos sem PDP, mas com presença de hiperestesia espinhal tem 3,9 vezes mais chances de recuperação quando comparado com cães na mesma condição, mas sem HE. Não foram encontrados trabalhos que avaliaram a HE mediante a palpação da coluna vertebral como um fator prognóstico, o que reforça a relevância do presente estudo. Os resultados do presente trabalho sugerem que a HE em cães paraplégicos acometidos por EDIV toracolombar sem presença de PDP pode ser utilizada como um possível indicador prognóstico de recuperação funcional.

Clinical management of dogs with presumptive diagnosis of cervical intervertebral disc disease: 78 cases (2006-2017) / Tratamento clínico de cães com diagnóstico presuntivo de doença do disco intervertebral cervical: 78 casos (2006-2017)

This study aimed to identify dogs with a presumptive diagnosis of cervical intervertebral disc disease (IVDD; C1-C5 or C6-T2) submitted to clinical management and evaluate the outcome. This study also aimed to demonstrate the age, sex, and treatment response according to the neurological degree, and verify whether those factors could potentially influence the outcome. The data were obtained from patients with a neurological dysfunction, admitted at the Veterinary Hospital from January 2006 to March 2017. In addition to patient records, the tutors answered a questionnaire related to the success of therapy. A hundred and seventy-seven neurological records were evaluated, and 78 were included in the study according to the inclusion criteria. The most frequent breeds were Dachshunds, followed by mixed-breed dogs. Regarding the neurological dysfunction degree, 58.97% presented grade I (only neck pain), 25.64% were grade II (ambulatory tetraparesis), and 15.38% grade III (nonambulatory tetraparesis). Absolute and partial space rest were performed in 75.64% and 24.36% of the cases, respectively. The minimum rest time was one week and could come up to four weeks. Most dogs were small-sized (≤15kg). The recovery was satisfactory in 87.17% of dogs and unsatisfactory in 12.83%. Regarding recurrence, we observed that 10.3% of dogs presented satisfactory recovery. The clinical treatment for dogs with cervical IVDD can be indicated with adequate clinical response to dysfunction degrees ranging from I to III, either at rest or in restricted space and with a low rate of relapse.(AU)

O objetivo desse estudo foi identificar cães com diagnóstico presuntivo de doença do disco intervertebral cervical (DDIV; C1-C5 ou C6-T2) submetidos ao tratamento clínico e avaliar a resposta a terapia instituída e o índice de recidiva. Esse estudo também visou demonstrar a idade, o gênero e a resposta ao tratamento de acordo com o grau neurológico, a fim de verificar se esses parâmetros podem ser utilizados como fatores prognósticos para a evolução clínica desses pacientes. Foram revisados os registros neurológicos do Hospital Veterinário Universitário de janeiro de 2006 a março de 2017. Realizaram coleta de dados a partir dos registros e por meio de um questionário respondido pelos tutores. Avaliaram 177 fichas neurológicas de cães e obtidas informações para inclusão no estudo em 78 delas. As raças mais frequentes foram Dachshunds, seguido dos cães sem raça definida. Quanto ao grau de disfunção neurológica, 58,97% apresentavam grau I (somente dor), 25,64% estavam em grau II (tetraparesia ambulatória) e 15,38% em grau III (tetraparesia não ambulatória). O repouso absoluto e em espaço restrito foram realizados em 75,64% e 24,36% dos casos, respectivamente e com duração de no mínimo uma semana, podendo chegar a mais de quatro semanas. A maioria dos animais era de pequeno porte (≤15kg). A recuperação foi satisfatória em 87,17% dos cães e insatisfatória em 12,83%. Quanto à recidiva, esta foi observada em 10,3% dos pacientes com recuperação satisfatória. O tratamento clínico para cães com DDIV cervical pode ser indicado com adequada resposta clínica para graus de disfunção que variam de I a III, seja em repouso absoluto ou em espaço restrito e com baixo índice de recidiva.(AU)

Clinical management of dogs with presumptive diagnosis of cervical intervertebral disc disease: 78 cases (2006-2017) / Tratamento clínico de cães com diagnóstico presuntivo de doença do disco intervertebral cervical: 78 casos (2006-2017)

This study aimed to identify dogs with a presumptive diagnosis of cervical intervertebral disc disease (IVDD; C1-C5 or C6-T2) submitted to clinical management and evaluate the outcome. This study also aimed to demonstrate the age, sex, and treatment response according to the neurological degree, and verify whether those factors could potentially influence the outcome. The data were obtained from patients with a neurological dysfunction, admitted at the Veterinary Hospital from January 2006 to March 2017. In addition to patient records, the tutors answered a questionnaire related to the success of therapy. A hundred and seventy-seven neurological records were evaluated, and 78 were included in the study according to the inclusion criteria. The most frequent breeds were Dachshunds, followed by mixed-breed dogs. Regarding the neurological dysfunction degree, 58.97% presented grade I (only neck pain), 25.64% were grade II (ambulatory tetraparesis), and 15.38% grade III (nonambulatory tetraparesis). Absolute and partial space rest were performed in 75.64% and 24.36% of the cases, respectively. The minimum rest time was one week and could come up to four weeks. Most dogs were small-sized (≤15kg). The recovery was satisfactory in 87.17% of dogs and unsatisfactory in 12.83%. Regarding recurrence, we observed that 10.3% of dogs presented satisfactory recovery. The clinical treatment for dogs with cervical IVDD can be indicated with adequate clinical response to dysfunction degrees ranging from I to III, either at rest or in restricted space and with a low rate of relapse.(AU)

O objetivo desse estudo foi identificar cães com diagnóstico presuntivo de doença do disco intervertebral cervical (DDIV; C1-C5 ou C6-T2) submetidos ao tratamento clínico e avaliar a resposta a terapia instituída e o índice de recidiva. Esse estudo também visou demonstrar a idade, o gênero e a resposta ao tratamento de acordo com o grau neurológico, a fim de verificar se esses parâmetros podem ser utilizados como fatores prognósticos para a evolução clínica desses pacientes. Foram revisados os registros neurológicos do Hospital Veterinário Universitário de janeiro de 2006 a março de 2017. Realizaram coleta de dados a partir dos registros e por meio de um questionário respondido pelos tutores. Avaliaram 177 fichas neurológicas de cães e obtidas informações para inclusão no estudo em 78 delas. As raças mais frequentes foram Dachshunds, seguido dos cães sem raça definida. Quanto ao grau de disfunção neurológica, 58,97% apresentavam grau I (somente dor), 25,64% estavam em grau II (tetraparesia ambulatória) e 15,38% em grau III (tetraparesia não ambulatória). O repouso absoluto e em espaço restrito foram realizados em 75,64% e 24,36% dos casos, respectivamente e com duração de no mínimo uma semana, podendo chegar a mais de quatro semanas. A maioria dos animais era de pequeno porte (≤15kg). A recuperação foi satisfatória em 87,17% dos cães e insatisfatória em 12,83%. Quanto à recidiva, esta foi observada em 10,3% dos pacientes com recuperação satisfatória. O tratamento clínico para cães com DDIV cervical pode ser indicado com adequada resposta clínica para graus de disfunção que variam de I a III, seja em repouso absoluto ou em espaço restrito e com baixo índice de recidiva.(AU)

Clinical management of dogs with presumptive diagnosis of thoracolumbar intervertebral disc disease: 164 cases (2006-2017) / Tratamento clínico de cães com diagnóstico presuntivo de doença do disco intervertebral toracolombar: 164 casos (2006-2017)

This study aimed to identify dogs with presumptive diagnosis of cervical intervertebral disc disease (IVDD) submitted to clinical management and to evaluate the outcomes. Data were obtained from the medical records of patients with neurological dysfunction assisted at a University Veterinary Hospital from 2006 to 2017. In addition to the patients' records, dog owners responded to a questionnaire on the success of therapy. Four hundred and thirteen neurological records were evaluated, and 164 met the inclusion criteria of the study. The most common breed was Dachshund, followed by mongrels. Classification of neurological dysfunction in the study sample was as follows: 15.9% with grade I, 25.6% with grade II, 26.8% with grade III, 8.5% with grade IV, and 23.2% with grade V. Outcome was satisfactory in 71.6% of the dogs and unsatisfactory in 28.4% of them. Recurrence was observed in 27.7% of those with satisfactory outcomes. The clinical treatment of dogs with thoracolumbar IVDD is satisfactory, particularly for animals with milder disease grades (I, II, and III). There is possibility of recurrence with conservative therapy and clinical signs may be more severe.(AU)

O objetivo desse estudo foi identificar cães com diagnóstico presuntivo de DDIV toracolombar submetidos ao tratamento clínico, a fim de avaliar a resposta à terapia instituída. Foram revisados os registros neurológicos de cães atendidos pelo Serviço de Neurologia e Neurocirurgia Veterinária no período de 2006 a 2017 de um Hospital Veterinário Universitário. Foi realizada coleta de dados a partir dos registros e por meio de um questionário respondido pelos tutores. Foram avaliadas 413 fichas neurológicas de cães e obtidas informações para inclusão no estudo em 164 delas. As raças mais frequentes foram dachshunds, seguido de cães sem raça definida. Quanto ao grau de disfunção neurológica foi definido como grau I para 15,9% dos cães, grau II para 25,6%, grau III para 26,8%, grau IV para 8,5% e grau V para 23,2%. A recuperação foi satisfatória em 71,6% dos cães e insatisfatória em 28,4%. Dos que se recuperaram satisfatoriamente, 27,7% tiveram recidivas. Com base nos resultados obtidos pode-se concluir que o tratamento clínico em repouso absoluto e administração de anti-inflamatórios e analgésicos opióides para cães com DDIV toracolombar é efetivo, principalmente para cães em graus mais leves da doença (grau I, II e III). Há possibilidade de recidiva com esse tipo de terapia cujos sinais clínicos poderão ser mais graves.(AU)

Clinical management of dogs with presumptive diagnosis of thoracolumbar intervertebral disc disease: 164 cases (2006-2017) / Tratamento clínico de cães com diagnóstico presuntivo de doença do disco intervertebral toracolombar: 164 casos (2006-2017)

This study aimed to identify dogs with presumptive diagnosis of cervical intervertebral disc disease (IVDD) submitted to clinical management and to evaluate the outcomes. Data were obtained from the medical records of patients with neurological dysfunction assisted at a University Veterinary Hospital from 2006 to 2017. In addition to the patients' records, dog owners responded to a questionnaire on the success of therapy. Four hundred and thirteen neurological records were evaluated, and 164 met the inclusion criteria of the study. The most common breed was Dachshund, followed by mongrels. Classification of neurological dysfunction in the study sample was as follows: 15.9% with grade I, 25.6% with grade II, 26.8% with grade III, 8.5% with grade IV, and 23.2% with grade V. Outcome was satisfactory in 71.6% of the dogs and unsatisfactory in 28.4% of them. Recurrence was observed in 27.7% of those with satisfactory outcomes. The clinical treatment of dogs with thoracolumbar IVDD is satisfactory, particularly for animals with milder disease grades (I, II, and III). There is possibility of recurrence with conservative therapy and clinical signs may be more severe.(AU)

O objetivo desse estudo foi identificar cães com diagnóstico presuntivo de DDIV toracolombar submetidos ao tratamento clínico, a fim de avaliar a resposta à terapia instituída. Foram revisados os registros neurológicos de cães atendidos pelo Serviço de Neurologia e Neurocirurgia Veterinária no período de 2006 a 2017 de um Hospital Veterinário Universitário. Foi realizada coleta de dados a partir dos registros e por meio de um questionário respondido pelos tutores. Foram avaliadas 413 fichas neurológicas de cães e obtidas informações para inclusão no estudo em 164 delas. As raças mais frequentes foram dachshunds, seguido de cães sem raça definida. Quanto ao grau de disfunção neurológica foi definido como grau I para 15,9% dos cães, grau II para 25,6%, grau III para 26,8%, grau IV para 8,5% e grau V para 23,2%. A recuperação foi satisfatória em 71,6% dos cães e insatisfatória em 28,4%. Dos que se recuperaram satisfatoriamente, 27,7% tiveram recidivas. Com base nos resultados obtidos pode-se concluir que o tratamento clínico em repouso absoluto e administração de anti-inflamatórios e analgésicos opióides para cães com DDIV toracolombar é efetivo, principalmente para cães em graus mais leves da doença (grau I, II e III). Há possibilidade de recidiva com esse tipo de terapia cujos sinais clínicos poderão ser mais graves.(AU)

Ventral slot in the clinical recovery of dogs with lateralized compression as a result of cervical intervertebral disc disease: 20 cases (2008-2018) / Fenda (slot) ventral na recuperação clínica de cães com compressões lateralizadas em decorrência da doença do disco intervertebral cervical: 20 casos (2008-2018)

The objective of this study was to verify the clinical recovery of dogs that underwent ventral slot surgical decompression with lateralized compressions of the cervical spinal cord caused by intervertebral disc disease (IVDD). Twenty patients were selected in different degrees of neurological dysfunction with definitive diagnosis of lateralized compression by cervical IVDD. Postoperative clinical recovery was assessed in patients who had undergone at least two months of the surgical procedure. There was a satisfactory recovery in 19 dogs (95%) and unsatisfactory recovery in another (5%), showing a significant clinical improvement (p 0.05) in the use of this technique in lateralized compression cases. The ventral slot promotes satisfactory clinical recovery of dogs with lateralized compression of the spinal cord caused by cervical IVDD and may be indicated as a surgical alternative.(AU)

O objetivo desse estudo foi verificar a recuperação clínica de cães submetidos a descompressão cirúrgica por fenda ventral em compressões lateralizadas da medula espinhal cervical ocasionada pela doença do disco intervertebral (DDIV). Foram selecionados 20 pacientes em diferentes graus de disfunção neurológica com diagnóstico definitivo de compressões lateralizadas por DDIV cervical. A recuperação clínica pós-operatória foi avaliada nos pacientes decorridos, no mínimo, dois meses do procedimento cirúrgico. Houve recuperação satisfatória em 19 cães (95%) e um insatisfatório (5%), demonstrando melhora clínica significativa (p 0,05) no emprego desta técnica em casos de compressões lateralizadas. A fenda ventral promove recuperação clínica satisfatória de cães com compressões lateralizadas da medula espinhal, ocasionadas pela DDIV cervical, e pode ser indicada como alternativa cirúrgica.(AU)

Development of a lumbosacral intervertebral cage prototype for dogs / Desenvolvimento de um protótipo de cage intervertebral lombossacro para cães

Several surgical procedures aim to decompress and/or stabilize the lumbosacral (LS) joint of dogs; however, the lumbar interbody fusion technique, by using a cage combined with a bone graft, is the most indicated and used in human medicine. No specific implant is available for application to the canine lumbosacral joint. Thus, this study measured lumbosacral discs in large dogs, determined whether a human cage model could fit the dogs' L7-S1 intervertebral space, and developed a LS cage prototype for dogs. Ten cadaveric lumbosacral spines from adult dog weighing 20-35kg were used. The dogs had died for reasons unrelated to this study. The vertebral body dimensions and the L7-S1 intervertebral space occupied by the intervertebral disc were measured by lateral and ventrodorsal radiographs and by computed tomography in the dorsal, sagittal, and transverse views. Measurements were also taken of the anatomical specimens in the sagittal and transverse planes. After measuring the intervertebral discs, the following mean measures were obtained for L7-S1 discs: height 12.23mm, dorsal thickness 3.3mm, central thickness 4mm, ventral thickness 5.5mm, and width 24.74mm. The human lumbar cage models from brands LDR, Baumer Orthopedics, Stryker, Synthes, and Vertebral Technologies, Inc. and cervical stabilization cages from the brands B-Braun and Stryker were evaluated and were found to be unsuitable for large dogs. Cervical human cages had measurements similar to those found in this study; however, due to their quadrangular shape, the possibility of being introduced surgically through the surgical accesses available for the articulation between L7-S1 in dogs without injuring the cauda equina or the L7 root is small. A cage model was then developed using 3D modelling software. It was designed for insertion via dorsal laminectomy in the lateral portions of the intervertebral space. To avoid cauda equina lesion, the implant model was developed to be placed laterally to the midline. The cage surface is serrated to prevent using the locking screw to fix it, thus avoiding further injury to nerve structures. The serrated surfaces are also designed to avoid cage migration and promote stability. The prototype allows graft placement in the surrounding intervertebral space, which is fundamental for fusion through integration between the cage and the endplates as well as for bone growth between and around the cage. It was also considered studies on humans showing that the lateral regions of the endplates support a more considerable load. Biomechanical and in vivo studies on the developed model are necessary to evaluate the actual degree of distraction, mobility and the long-term rate of fusion between L7 and S1 and its possible impact on the adjacent motor units, combined or not with dorsal fixation techniques.(AU)

Vários procedimentos cirúrgicos visam descomprimir e/ou estabilizar a articulação lombossacra (LS) de cães; no entanto, a técnica de fusão lombar, usando um cage intersomático combinado com um enxerto ósseo, é a mais indicada e utilizada na medicina humana. Não há implante específico disponível para aplicação na articulação lombossacra canina. Assim, neste estudo foi realizada a mensuração do espaço do disco intervertebral lombossacro de cães de raças grandes, para verificar se algum modelo de cage usado na medicina humana poderia ser usado no espaço intervertebral L7-S1 de cães. O segundo objetivo foi desenvolver um protótipo de cage lombossacro para cães. Foram utilizadas dez colunas lombossacras provenientes de cadáveres de cães adultos com peso entre 20 e 35kg. Os cães vieram a óbito por razões não relacionadas a este estudo. As dimensões do corpo vertebral e o espaço intervertebral L7-S1 ocupado pelo disco intervertebral foram medidos por radiografias laterais e ventrodorsais e por tomografia computadorizada nos cortes dorsal, sagital e transversal. Também foram realizadas mensurações das peças anatômicas nos planos sagital e transversal. Após a mensuração dos discos intervertebrais, foram obtidas as seguintes medidas médias dos discos L7-S1: altura 12,23mm, espessura dorsal 3,3mm, espessura central 4mm, espessura ventral 5,5mm e largura 24,74mm. Os modelos de cage lombar humano das marcas LDR, Baumer Orthopaedics, Stryker, Synthes e Vertebral Technologies, Inc. não possuíam dimensões adequadas para os cães. Cages de estabilização cervical das marcas B-Braun e Stryker também foram avaliados e apresentaram medidas semelhantes às encontradas neste estudo; no entanto, devido à sua forma quadrangular, a possibilidade de serem introduzidos cirurgicamente através das abordagens disponíveis para a articulação entre L7-S1 em cães sem lesionar a cauda equina ou a raiz L7 é pequena. Um modelo de cage foi então desenvolvido usando-se o software de modelagem 3D. Foi projetado para inserção via laminectomia dorsal nas porções laterais do espaço intervertebral. Para evitar a lesão da cauda equina, o modelo de implante foi desenvolvido para ser colocado lateralmente à linha média. A superfície do cage é serrilhada para evitar o uso do parafuso de travamento, evitando-se lesões adicionais às estruturas nervosas. As superfícies serrilhadas também foram projetadas para evitar a migração do cage e promover estabilidade. O protótipo permite a colocação do enxerto no espaço intervertebral circundante, fundamental para a fusão através da integração entre o cage e as placas vertebrais terminais, bem como para o crescimento ósseo entre e ao redor do implante. Também foram considerados estudos em seres humanos que mostraram que as regiões laterais das placas vertebrais terminais suportam uma carga maior. São necessários estudos biomecânicos e in vivo do modelo desenvolvido para avaliar o grau real de distração, mobilidade e a taxa de fusão a longo prazo entre L7 e S1 e seu possível impacto nas unidades motoras adjacentes, quando combinado ou não com técnicas de fixação dorsal.(AU)

Proposta de sequenciamento das projeções mielográficas na identificação de compressão da medula espinhal em cães com doença do disco intervertebral cervical / [Sequential proposal in the myelographic views for detection of spinal cord compression in dogs with cervical intervertebral disc disease]

O objetivo deste trabalho foi verificar em quais projeções foi possível identificar compressão da medula espinhal em cães com doença do disco intervertebral (DDIV) cervical e propor um sequenciamento das projeções a ser realizado no exame mielográfico dessa região. Foram avaliadas quatro projeções mielográficas (lateral, ventrodorsal e oblíquas esquerda e direita) de 41 pacientes diagnosticados com DDIV cervical. Em 40 pacientes (97,5%), foi possível identificar compressão da medula espinhal na projeção lateral; em 22 (53,6%), nas oblíquas; e em 11 (26,8%), na ventrodorsal (P<0,05). Havia lateralização da compressão em 22 (53,6%) pacientes; 100% delas (n=22) foram detectadas pelas projeções oblíquas e 50% (n=11) pela ventrodorsal. Em 10 (24,4%) cães, foi observado mais que um local de compressão, tendo as projeções ventrodorsal e oblíquas auxiliado na definição do local de compressão em 50% e 70%, respectivamente. Pode-se concluir que todas as projeções mielográficas estudadas permitem identificar compressão na medula espinhal em cães com DDIV cervical, sendo a incidência lateral a que mais a revelou, seguida das oblíquas e da ventrodorsal, estabelecendo-se, assim, uma proposta de sequenciamento das projeções mielográficas a serem realizadas para essa região.(AU)

The aim of this study was to verify in which of the myelographic views it was possible to identify spinal cord compression in dogs with cervical intervertebral disc disease (IVDD), and to establish a sequence in which myelographic views should be obtained for this region. Four myelographic views (lateral, ventrodorsal, left oblique and right oblique) of 41 patients diagnosed with cervical IVDD were evaluated. In 40 patients (97.5%) it was possible to identify spinal cord compression by lateral view, 22 (53.6%) by the oblique view, and 11 (26.8%) by the ventrodorsal view (P< 0.05). There were lateralized compressions in 22 (53.6%) patients, detected by all oblique views (100%) and by 11 (50%) of the ventrodorsal views. In 10 (24.4%) dogs, more than one compression site was observed, where the ventrodorsal view helped to decide the site in 50% of the cases and oblique in 70%. It can be concluded that all the tested myelographic views allow the identification of spinal cord compressions in dogs with cervical IVDD, the lateral view being the most relevant, followed by the oblique and ventrodorsal view, therefore establishing a sequence of myelographic views should be obtained for this region.(AU)

Proposta de sequenciamento das projeções mielográficas na identificação de compressão da medula espinhal em cães com doença do disco intervertebral cervical / [Sequential proposal in the myelographic views for detection of spinal cord compression in dogs with cervical intervertebral disc disease]

O objetivo deste trabalho foi verificar em quais projeções foi possível identificar compressão da medula espinhal em cães com doença do disco intervertebral (DDIV) cervical e propor um sequenciamento das projeções a ser realizado no exame mielográfico dessa região. Foram avaliadas quatro projeções mielográficas (lateral, ventrodorsal e oblíquas esquerda e direita) de 41 pacientes diagnosticados com DDIV cervical. Em 40 pacientes (97,5%), foi possível identificar compressão da medula espinhal na projeção lateral; em 22 (53,6%), nas oblíquas; e em 11 (26,8%), na ventrodorsal (P<0,05). Havia lateralização da compressão em 22 (53,6%) pacientes; 100% delas (n=22) foram detectadas pelas projeções oblíquas e 50% (n=11) pela ventrodorsal. Em 10 (24,4%) cães, foi observado mais que um local de compressão, tendo as projeções ventrodorsal e oblíquas auxiliado na definição do local de compressão em 50% e 70%, respectivamente. Pode-se concluir que todas as projeções mielográficas estudadas permitem identificar compressão na medula espinhal em cães com DDIV cervical, sendo a incidência lateral a que mais a revelou, seguida das oblíquas e da ventrodorsal, estabelecendo-se, assim, uma proposta de sequenciamento das projeções mielográficas a serem realizadas para essa região.(AU)

The aim of this study was to verify in which of the myelographic views it was possible to identify spinal cord compression in dogs with cervical intervertebral disc disease (IVDD), and to establish a sequence in which myelographic views should be obtained for this region. Four myelographic views (lateral, ventrodorsal, left oblique and right oblique) of 41 patients diagnosed with cervical IVDD were evaluated. In 40 patients (97.5%) it was possible to identify spinal cord compression by lateral view, 22 (53.6%) by the oblique view, and 11 (26.8%) by the ventrodorsal view (P< 0.05). There were lateralized compressions in 22 (53.6%) patients, detected by all oblique views (100%) and by 11 (50%) of the ventrodorsal views. In 10 (24.4%) dogs, more than one compression site was observed, where the ventrodorsal view helped to decide the site in 50% of the cases and oblique in 70%. It can be concluded that all the tested myelographic views allow the identification of spinal cord compressions in dogs with cervical IVDD, the lateral view being the most relevant, followed by the oblique and ventrodorsal view, therefore establishing a sequence of myelographic views should be obtained for this region.(AU)

Extrusão de disco intervertebral intradural em um cão / Intradural disc extrusion in a dog

Background: Intervertebral disc extrusion is an important cause of spinal cord dysfunction in dogs. Intradural localizationof the extruded disc material is rare, and is generally associated with a traumatic event or with recurrence of disc extrusionat a previously affected site. We report the clinical presentation, diagnostic workup, and treatment of a dog with intraduralintervertebral disc extrusion not preceded by a traumatic event.Case: A 6-year-old male Dachshund was referred for neurological evaluation due to acute onset of hind-end paralysispreceded by claudication of the left hindlimb. The patient had been receiving conservative treatment to no effect. Neurological examination revealed asymmetric non-ambulatory paraparesis, absence of postural reactions and decreased muscletone in both hindlimbs, a bilaterally diminished patellar reflex, and a hindlimb withdrawal reflex which was normal onthe right and greatly diminished to absent on the left. The lower back was tender to epaxial palpation. Plain radiographsof the lumbar spine in the lateral projection showed calcified material within the spinal canal between the third and fourthlumbar vertebrae. Myelography was suggestively abnormal at the same level, with epidural leakage of contrast at L3-L4.Considering the clinical history, breed, age, neurological signs, and radiographic findings, intervertebral disc disease wassuspected despite the inconclusive myelography findings. A dorsolateral lumbar hemilaminectomy was performed. Intraoperatively, the diagnosis was confirmed by visualization of a discolored spinal cord and absence of extradural material.The intradural space was accessed via durotomy. A firm, straw-yellow material was seen compressing the spinal cord andremoved. Subsequent histopathological...

Extrusão de disco intervertebral intradural em um cão / Intradural disc extrusion in a dog

Background: Intervertebral disc extrusion is an important cause of spinal cord dysfunction in dogs. Intradural localizationof the extruded disc material is rare, and is generally associated with a traumatic event or with recurrence of disc extrusionat a previously affected site. We report the clinical presentation, diagnostic workup, and treatment of a dog with intraduralintervertebral disc extrusion not preceded by a traumatic event.Case: A 6-year-old male Dachshund was referred for neurological evaluation due to acute onset of hind-end paralysispreceded by claudication of the left hindlimb. The patient had been receiving conservative treatment to no effect. Neurological examination revealed asymmetric non-ambulatory paraparesis, absence of postural reactions and decreased muscletone in both hindlimbs, a bilaterally diminished patellar reflex, and a hindlimb withdrawal reflex which was normal onthe right and greatly diminished to absent on the left. The lower back was tender to epaxial palpation. Plain radiographsof the lumbar spine in the lateral projection showed calcified material within the spinal canal between the third and fourthlumbar vertebrae. Myelography was suggestively abnormal at the same level, with epidural leakage of contrast at L3-L4.Considering the clinical history, breed, age, neurological signs, and radiographic findings, intervertebral disc disease wassuspected despite the inconclusive myelography findings. A dorsolateral lumbar hemilaminectomy was performed. Intraoperatively, the diagnosis was confirmed by visualization of a discolored spinal cord and absence of extradural material.The intradural space was accessed via durotomy. A firm, straw-yellow material was seen compressing the spinal cord andremoved. Subsequent histopathological...(AU)

Aortic and iliac thrombosis in a dog with adrenal-dependent hypercortisolism due to bilateral adrenocortical adenoma / Trombose aórtica e ilíaca em um cão com hipercortisolismo adrenal-dependente devido a adenoma adrenocortical bilateral

Hypercortisolism is a common endocrinopathy in dogs; however, in a few cases, bilateral functional adrenocortical adenomas cause spontaneous disease, and thrombotic events are considered uncommon complications. The aim of this report was to describe a case of bilateral adrenocortical adenoma in a dog with hyperadrenocorticism associated with distal aortic and iliac thrombosis, with emphasis on clinical and pathological aspects. A 15-year-old spayed female Dachshund with a previous clinical history of hyperadrenocorticism presented with acute bilateral hindlimb paraparesis. A vertebral thoracolumbar radiography was performed and did not present any evidence of intervertebral disk disease or vertebral abnormalities; however, abdominal ultrasound and vascular Doppler evaluation revealed bilateral adrenal enlargement in addition to an aortic and external iliac artery thrombus. The animal was euthanized. At necropsy, both adrenal glands were enlarged by well-demarcated neoplastic nodules in the parenchyma, and a thrombus caudal to the abdominal aorta bifurcation within the external iliac arteries that extended to the left external iliac artery was noted. Histological evaluation revealed a well-differentiated neoplastic proliferation of cortical epithelial cells, consistent with bilateral adenoma, and muscular necrosis in the pelvic limbs was also observed. Bilateral functional adrenocortical adenoma; although, very rare, should be considered as a cause of hypercortisolism, and aortic thrombosis in dogs should be considered as a possible consequence.(AU)

Hipercortisolismo é uma endocrinopatia comum em cães, no entanto, apenas em poucos casos adenomas adrenocorticais funcionais bilaterais são a causa de doença espontânea, e eventos trombóticos são considerados complicações incomuns. O objetivo deste relato foi descrever um caso de adenoma adrenocortical bilateral em um cão com hiperadrenocorticismo associado a trombose aórtica distal e ilíaca, com ênfase nos aspectos clínicos e patológicos. Um cão, Dachshund, fêmea castrada, de 15 anos, com histórico clínico prévio de hiperadrenocorticismo, apresentou paraparesia aguda dos membros posteriores. Foi realizada radiografia toracolombar vertebral, a qual não mostrou nenhuma evidência de doença do disco intervertebral ou anormalidades vertebrais; no entanto, ultrassonografia abdominal e Doppler vascular revelaram um trombo na aorta e artéria ilíaca externa, e adrenomegalia bilateral. O animal foi submetido à eutanásia. Na necropsia, ambas as adrenais estavam distendidas por nódulos neoplásicos bem delimitados no parênquima e notou-se um trombo caudalmente à bifurcação da aorta abdominal às artérias ilíacas externas, estendendo-se à ilíaca externa esquerda. Na avaliação histológica observou-se proliferação neoplásica bem diferenciada de células epiteliais corticais, consistente com adenoma bilateral; também foi observada necrose muscular nos membros pélvicos. O adenoma adrenocortical funcional bilateral, embora muito raro, deve ser considerado uma causa de hipercortisolismo, e a trombose aórtica em cães deve ser considerada uma possível consequência.(AU)

Hérnia de disco sequestrada em cão / Sequestered disc herniation in dog

Background: Dogs are frequently affected by intervertebral disc degeneration, a structural failure associated with changesaccelerated by aging. Disc degeneration may occur in the presence or absence of clinical signs, which are variable andcommon to other spinal cord diseases and therefore early diagnosis is crucial to a successful outcome. Treatment may beconservative or surgical according to severity of the clinical signs and should be combined with a rehabilitation protocol.Prognosis depends on the location of the spinal cord compression, volume and velocity of the disc material herniation andtime between initial clinical signs, definitive diagnosis and therapeutic approach.Case: A nonchondrodystrophic 14-year-old dog with acute clinical manifestation of paraparesis and proprioceptive deficitin hind limbs was submitted to myelography examination. There was contrast column deviation in the T13-L1 region,determining spinal compression, and spondyloses were also noted in several thoracolumbar vertebrae. Hemilaminectomywas performed with complete removal of the compressor fragment. Histological analysis confirmed the presence of fibrocartilaginous material that corresponds to the part of the annulus fibrosus. The kidnap of the fragment was characterizedby loss of continuity with the remaining disk. In these cases, magnetic resonance imaging does provides the definitivediagnosis, since neoplasm, arachnoid cysts and abscesses may be remaining differential diagnosis. Therefore, surgical approach followed by histopathological analysis of the obtained material are necessary to confirm the diagnosis.Discussion: The present report differs from most cases of disc herniation because it is a thoracolumbar lesion with an acutemanifestation of significant neurological deficit in an elderly dog of non-chondrodystophic...

Hérnia de disco sequestrada em cão / Sequestered disc herniation in dog

Background: Dogs are frequently affected by intervertebral disc degeneration, a structural failure associated with changesaccelerated by aging. Disc degeneration may occur in the presence or absence of clinical signs, which are variable andcommon to other spinal cord diseases and therefore early diagnosis is crucial to a successful outcome. Treatment may beconservative or surgical according to severity of the clinical signs and should be combined with a rehabilitation protocol.Prognosis depends on the location of the spinal cord compression, volume and velocity of the disc material herniation andtime between initial clinical signs, definitive diagnosis and therapeutic approach.Case: A nonchondrodystrophic 14-year-old dog with acute clinical manifestation of paraparesis and proprioceptive deficitin hind limbs was submitted to myelography examination. There was contrast column deviation in the T13-L1 region,determining spinal compression, and spondyloses were also noted in several thoracolumbar vertebrae. Hemilaminectomywas performed with complete removal of the compressor fragment. Histological analysis confirmed the presence of fibrocartilaginous material that corresponds to the part of the annulus fibrosus. The kidnap of the fragment was characterizedby loss of continuity with the remaining disk. In these cases, magnetic resonance imaging does provides the definitivediagnosis, since neoplasm, arachnoid cysts and abscesses may be remaining differential diagnosis. Therefore, surgical approach followed by histopathological analysis of the obtained material are necessary to confirm the diagnosis.Discussion: The present report differs from most cases of disc herniation because it is a thoracolumbar lesion with an acutemanifestation of significant neurological deficit in an elderly dog of non-chondrodystophic...(AU)

Hérnia de disco tipo III em um cão / Type III disc herniation in a dog

Background: Acute and non-compressive nucleus pulposus extrusion, also called type III disc herniation, usually results from extreme exercises or traumatic episodes and is characterized by an acute extrusion without a compression of the spinal cord. Extrusion reaches the spinal cord at high speed, causing bruising in its parenchyma, and dissipates through the epidural space without causing compression. This report aims to describe the clinical signs, diagnosis and treatment of a canine patient possibly affected by acute non-compressive extrusion of the intervertebral disc, as well as the evolution of the case with the proposed therapy.Case: A 7-year-old male Dachshund, weighing 9.4 kg, was presented with an acute loss of hind limb locomotion. At the neurological examination, paraplegia of acute onset with absence of deep pain, increased muscle tone, and increased patellar and withdrawal reflexes in hind limbs was found, as well as pain on epaxial palpation of the thoracolumbar spine. The perineal reflex was preserved, and the cutaneous trunci reflex was absent until the level of the second lumbar vertebra (L2). Magnetic resonance imaging (MRI) showed an uncompressed heterogeneous hyper intense area in the thoracolumbar spinal cord on the intervertebral disc (IVD) between T13-L1. Based on the imaging findings, a presumptive diagnosis of an acute non-compressive disc extrusion was assumed, thus discarding the need for surgical decompression. The patient was hospitalized, initially being treated with dexamethasone, tramadol and dipyrone. After 24 hours of hospitalization, the dog recovered deep pain in the pelvic limbs and control over urination. The dog was then discharged from hospital and was prescribed prednisolone and absolute rest. After 25 days of clinical onset, there was a significant improvement in the patient neurological status, presenting only an ataxia of the pelvic limbs.[...]

Hérnia de disco tipo III em um cão / Type III disc herniation in a dog

Background: Acute and non-compressive nucleus pulposus extrusion, also called type III disc herniation, usually results from extreme exercises or traumatic episodes and is characterized by an acute extrusion without a compression of the spinal cord. Extrusion reaches the spinal cord at high speed, causing bruising in its parenchyma, and dissipates through the epidural space without causing compression. This report aims to describe the clinical signs, diagnosis and treatment of a canine patient possibly affected by acute non-compressive extrusion of the intervertebral disc, as well as the evolution of the case with the proposed therapy.Case: A 7-year-old male Dachshund, weighing 9.4 kg, was presented with an acute loss of hind limb locomotion. At the neurological examination, paraplegia of acute onset with absence of deep pain, increased muscle tone, and increased patellar and withdrawal reflexes in hind limbs was found, as well as pain on epaxial palpation of the thoracolumbar spine. The perineal reflex was preserved, and the cutaneous trunci reflex was absent until the level of the second lumbar vertebra (L2). Magnetic resonance imaging (MRI) showed an uncompressed heterogeneous hyper intense area in the thoracolumbar spinal cord on the intervertebral disc (IVD) between T13-L1. Based on the imaging findings, a presumptive diagnosis of an acute non-compressive disc extrusion was assumed, thus discarding the need for surgical decompression. The patient was hospitalized, initially being treated with dexamethasone, tramadol and dipyrone. After 24 hours of hospitalization, the dog recovered deep pain in the pelvic limbs and control over urination. The dog was then discharged from hospital and was prescribed prednisolone and absolute rest. After 25 days of clinical onset, there was a significant improvement in the patient neurological status, presenting only an ataxia of the pelvic limbs.[...](AU)

Diagnóstico por imagen de la hernia discal Hansen tipo I, II y III en los perros / Imaging diagnostic of Hansen type I, II and III disc herniation in dogs / Diagnóstico por imagem de hérnia discal Hansen tipo I, II e III em cães

Para este estudio, se realizó una literatura sobre los métodos de diagnóstico de la hernia de disco, que es la enfermedad del disco más común en los perros y se relaciona con trastornos neurológicos que implican la médula espinal. La hernia de disco es la causa principal para la investigación por imagen de la columna vertebral en los animales pequeños. El diagnóstico por imagen es esencial para la comprensión de la enfermedad, la localización de la lesión y la gravedad. Las pruebas más comunes que se realizan en la medicina veterinaria son la radiografía y la mielografía, debido a que son más asequibles, pero el diagnóstico exacto es a través de la tomografía computarizada o resonancia magnética, siendo esta última la principal técnica de discopatías. Estos factores, así como su etiología, fisiopatología y la predisposición también serán abordados en este trabajo.(AU)

For the present study was reviewed bibliography about the diagnostic methods of disc herniation, which it is the discopathy most common in dogs and it is related to neurological disorders involving the spinal cord. Disc herniation is the main cause for the imaging investigation of the spine in small animal. Diagnostic imaging is fundamental to have knowledge of the disease, the location and severity of the lesion. The most common examinations performed in veterinary medicine are radiography and myelography, because they are more accessible, but an accurate diagnosis is made through computed tomography or magnetic resonance, being the latter the primary technique to the discopathy. These factors, as well as the etiology and pathophysiology will be approached also in this study.(AU)

Para o presente trabalho, foi realizado um levantamento bibliográfico abordando os métodos diagnósticos da hérnia discal, a qual é a discopatia mais comum em cães e está relacionada aos distúrbios neurológicos que envolvem a medula espinhal. A hérnia discal é a principal causa para a investigação imagenológica da coluna vertebral em pequenos animais. O diagnóstico por imagem é fundamental para obter o conhecimento da doença, da localidade da lesão e da gravidade. Os exames mais comuns realizados na rotina veterinária são a radiografia e a mielografia, por serem mais acessíveis, porém o diagnóstico preciso se dá por meio da tomografia computadorizada ou da ressonância magnética, sendo esta última a técnica primordial para as discopatias. Esses fatores, bem como sua etiologia, fisiopatologia e predisposição serão abordados também neste estudo.(AU)

Diagnóstico por imagen de la hernia discal Hansen tipo I, II y III en los perros / Imaging diagnostic of Hansen type I, II and III disc herniation in dogs / Diagnóstico por imagem de hérnia discal Hansen tipo I, II e III em cães

Para este estudio, se realizó una literatura sobre los métodos de diagnóstico de la hernia de disco, que es la enfermedad del disco más común en los perros y se relaciona con trastornos neurológicos que implican la médula espinal. La hernia de disco es la causa principal para la investigación por imagen de la columna vertebral en los animales pequeños. El diagnóstico por imagen es esencial para la comprensión de la enfermedad, la localización de la lesión y la gravedad. Las pruebas más comunes que se realizan en la medicina veterinaria son la radiografía y la mielografía, debido a que son más asequibles, pero el diagnóstico exacto es a través de la tomografía computarizada o resonancia magnética, siendo esta última la principal técnica de discopatías. Estos factores, así como su etiología, fisiopatología y la predisposición también serán abordados en este trabajo.

For the present study was reviewed bibliography about the diagnostic methods of disc herniation, which it is the discopathy most common in dogs and it is related to neurological disorders involving the spinal cord. Disc herniation is the main cause for the imaging investigation of the spine in small animal. Diagnostic imaging is fundamental to have knowledge of the disease, the location and severity of the lesion. The most common examinations performed in veterinary medicine are radiography and myelography, because they are more accessible, but an accurate diagnosis is made through computed tomography or magnetic resonance, being the latter the primary technique to the discopathy. These factors, as well as the etiology and pathophysiology will be approached also in this study.

Para o presente trabalho, foi realizado um levantamento bibliográfico abordando os métodos diagnósticos da hérnia discal, a qual é a discopatia mais comum em cães e está relacionada aos distúrbios neurológicos que envolvem a medula espinhal. A hérnia discal é a principal causa para a investigação imagenológica da coluna vertebral em pequenos animais. O diagnóstico por imagem é fundamental para obter o conhecimento da doença, da localidade da lesão e da gravidade. Os exames mais comuns realizados na rotina veterinária são a radiografia e a mielografia, por serem mais acessíveis, porém o diagnóstico preciso se dá por meio da tomografia computadorizada ou da ressonância magnética, sendo esta última a técnica primordial para as discopatias. Esses fatores, bem como sua etiologia, fisiopatologia e predisposição serão abordados também neste estudo.