Estabilização cirúrgica da coluna vertebral cervical em ovino / Cervical spinal cord surgical stabilization in a sheep

Background: Trauma is the main cause of spinal fractures and dislocations in humans and large animals. Clinical signspresent with acute onset and vary according to the location and severity of the spinal cord injury. The treatment of fractures in large animals depends on economic value, cost of procedures, prognosis, location and type of fracture. However,although spinal fractures in large animals are not uncommon, the literature about their clinical aspects and treatment isscanty. Therefore, the purpose of this report is to describe a surgical stabilization of atlantoaxial subluxation, fracture ofthe third cervical vertebra and C2-C3 subluxation.Case: An approximately 2-year-old Île-de-France sheep, weighing 101 kg, with a history of cervical trauma and nonambulatory tetraparesis was treated at the Veterinary Hospital of the Institution (UNIPAMPA). During physical examination, the animal presented good general physical condition and heart rate, respiratory rate and temperature was accordingto physiological parameters for the species. The animal remained in lateral decubitus, with minimal head and limb movements, and exhibited deep pain sensitivity. Clinical treatment with dexamethasone, limb physiotherapy and change inlateral decubitus position were employed, but failed to improve the animal’s condition. After five days of unresponsive toclinical treatment, the patient was referred to the neurology department, where it underwent neurological examination andradiographic examination of the cervical region was performed under general anesthesia. The radiographic examinationrevealed atlantoaxial subluxation, by displacement of the odontoid process into the vertebral canal, fracture of the thirdcervical vertebra and C2-C3 vertebral subluxation. The surgical planning aimed cervical vertebral instability repair usingatlantoaxial arthrodesis associated the stabilization of C1-C2 and C2-C3 vertebrae with Schanz pins and bone cement...

Estabilização cirúrgica da coluna vertebral cervical em ovino / Cervical spinal cord surgical stabilization in a sheep

Background: Trauma is the main cause of spinal fractures and dislocations in humans and large animals. Clinical signspresent with acute onset and vary according to the location and severity of the spinal cord injury. The treatment of fractures in large animals depends on economic value, cost of procedures, prognosis, location and type of fracture. However,although spinal fractures in large animals are not uncommon, the literature about their clinical aspects and treatment isscanty. Therefore, the purpose of this report is to describe a surgical stabilization of atlantoaxial subluxation, fracture ofthe third cervical vertebra and C2-C3 subluxation.Case: An approximately 2-year-old Île-de-France sheep, weighing 101 kg, with a history of cervical trauma and nonambulatory tetraparesis was treated at the Veterinary Hospital of the Institution (UNIPAMPA). During physical examination, the animal presented good general physical condition and heart rate, respiratory rate and temperature was accordingto physiological parameters for the species. The animal remained in lateral decubitus, with minimal head and limb movements, and exhibited deep pain sensitivity. Clinical treatment with dexamethasone, limb physiotherapy and change inlateral decubitus position were employed, but failed to improve the animals condition. After five days of unresponsive toclinical treatment, the patient was referred to the neurology department, where it underwent neurological examination andradiographic examination of the cervical region was performed under general anesthesia. The radiographic examinationrevealed atlantoaxial subluxation, by displacement of the odontoid process into the vertebral canal, fracture of the thirdcervical vertebra and C2-C3 vertebral subluxation. The surgical planning aimed cervical vertebral instability repair usingatlantoaxial arthrodesis associated the stabilization of C1-C2 and C2-C3 vertebrae with Schanz pins and bone cement...(AU)

Carcinoma com metástase em coluna vertebral em dois cães / Carcinoma with vertebral column metastasis in two dogs

Background: Carcinomas are aggressive and invasive malignancies that originate from any type of epithelial cell and are responsible for many deaths in dogs. Carcinoma metastases occur primarily via the lymphatic route; however, they can occur by blood flow, thus reaching bone structures. In dogs, metastasis of mammary and squamous cell carcinomas to the skeletal system is poorly described. The aim of this study was to report two cases of dogs that developed metastases of carcinomas to the vertebral column. Cases: Case 1. A 10-year-old, male, mixed-breed dog with paralysis of the left pelvic limb, subcutaneous mass in the lumbar region, apathy, anorexia and progressive weight loss and with a previous history of amputation of the right pelvic limb resulting from squamous cell carcinoma (SCC) in the integument of the cranial face of the femorotibiopatellar joint. Due to the patient’s clinical condition and the negative prognosis associated with the neoplasia, euthanasia was performed. At necropsy, infiltrating the lumbar vertebrae from L5 to L7, a whitish and firm mass of approximately 15 x 8 cm was observed. Histologically, it comprised a malignant epithelial neoplastic development consisting of nests and cords interspersed with fibrovascular stroma, containing multiple keratine pearls. There was moderate to severe anisocytosis, severe anisokariosis, and about 4 mitosis figures for every 10 high power fields (400x). The histological features were consistent with an invasive SCC. Anti-cytokeratin and anti-p63 immunohistochemical (IHC) evaluations were performed, both with immunoreactivity in neoplastic cells. Case 2. An 8-year-old, female, Chihuahua with bilateral paralysis of the pelvic limbs, anorexia, and progressive weight loss, with a history of excision of solid mammary carcinoma. The clinical condition...

Carcinoma com metástase em coluna vertebral em dois cães / Carcinoma with vertebral column metastasis in two dogs

Background: Carcinomas are aggressive and invasive malignancies that originate from any type of epithelial cell and are responsible for many deaths in dogs. Carcinoma metastases occur primarily via the lymphatic route; however, they can occur by blood flow, thus reaching bone structures. In dogs, metastasis of mammary and squamous cell carcinomas to the skeletal system is poorly described. The aim of this study was to report two cases of dogs that developed metastases of carcinomas to the vertebral column. Cases: Case 1. A 10-year-old, male, mixed-breed dog with paralysis of the left pelvic limb, subcutaneous mass in the lumbar region, apathy, anorexia and progressive weight loss and with a previous history of amputation of the right pelvic limb resulting from squamous cell carcinoma (SCC) in the integument of the cranial face of the femorotibiopatellar joint. Due to the patients clinical condition and the negative prognosis associated with the neoplasia, euthanasia was performed. At necropsy, infiltrating the lumbar vertebrae from L5 to L7, a whitish and firm mass of approximately 15 x 8 cm was observed. Histologically, it comprised a malignant epithelial neoplastic development consisting of nests and cords interspersed with fibrovascular stroma, containing multiple keratine pearls. There was moderate to severe anisocytosis, severe anisokariosis, and about 4 mitosis figures for every 10 high power fields (400x). The histological features were consistent with an invasive SCC. Anti-cytokeratin and anti-p63 immunohistochemical (IHC) evaluations were performed, both with immunoreactivity in neoplastic cells. Case 2. An 8-year-old, female, Chihuahua with bilateral paralysis of the pelvic limbs, anorexia, and progressive weight loss, with a history of excision of solid mammary carcinoma. The clinical condition...(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...

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)

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)

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)

Corpectomia lateral parcial para o tratamento de compressão ventral extradural crônica entre T9-T10 em um cão / Partial lateral corpectomy for treatment of chronic ventral extradural compression between T9-T10 in a dog

Objetivou-se relatar um caso de protrusão do disco intervertebral com localização atípica e descrever a técnica cirúrgica de corpectomia lateral parcial no tratamento da afecção em um cão. Um cão de sete anos de idade, macho, raça Pug, foi atendido com ataxia proprioceptiva dos membros pélvicos havia três meses, associada à doença do disco intervertebral entre a nona e 10ª vértebras torácicas. Após um mês de tratamento conservativo sem melhora, o paciente foi encaminhado para o tratamento cirúrgico, quando foi realizada corpectomia lateral parcial esquerda para descompressão da medula espinhal. Após a cirurgia, o paciente apresentou melhora considerável do quadro, sendo a técnica eficaz na remoção da compressão extradural, sem manipulação da medula espinhal ou outras complicações.(AU)

The aim of this study is to report a case of intervertebral disc protrusion with atypical location and describe the surgical technique of partial lateral corpectomy in the treatment of this disease in a dog. A dog, seven -years-old, male, Pug breed was attended with proprioceptive ataxia of the hind limbs for three months correlated with intervertebral disc disease between the 9th and 10th thoracic vertebrae. After a month of conservative treatment without improvements, the patient was referred for surgical treatment, which was performed as a partial left lateral corpectomy for decompression of the spinal cord. After surgery, the patient showed considerable improvement, this technique being shown to be effective in the removal of extradural compression, without manipulation of the spinal cord or other complications.(AU)

Ensaio biomecânico para determinação do diâmetro de barra conectora de polimetilmetacrilato em fixador esquelético externo tipo Ia no úmero de suínos / Biomechanical test to determination the diameter of the polymethylmethacrylate bar in external skeletal fixator type Ia in swine humerusi

Fraturas ósseas podem ser corrigidas com a utilização de fixadores esqueléticos externos (FEE), método de estabilização bastante comum. Para tanto, têm-se utilizado barras conectoras de polimetilmetacrilato (PMMA) sem critério de diâmetro, as quais podem quebrar, se ficarem muito delgadas, ou ocasionar incômodo, quando muito pesadas e volumosas. O objetivo deste trabalho foi testar, por meio de ensaio biomecânico de compressão axial e flexão, qual é o diâmetro ideal da barra conectora de PMMA, correlacionado com o diâmetro ósseo para utilização em FEE tipo Ia. Utilizaram-se 24 úmeros para se realizarem medidas de comprimento, diâmetro, circunferência e ensaios biomecânicos. Após, foram confeccionadas barras de 1,5 vezes a média do diâmetro ósseo (grupo I), do mesmo diâmetro ósseo (grupo II) e de 0,5 vezes o diâmetro (grupo III). Com os resultados obtidos ao se compararem os valores dos ossos com os dos grupos II e III, verificou-se que as barras conectoras do grupo II mostraram-se mais resistentes do que o tecido ósseo no ensaio de compressão. No ensaio de flexão, os ossos resistiram mais quando comparados aos grupos II e III, sendo 4,3 vezes mais resistentes do que o grupo III nesse mesmo ensaio mecânico. Os resultados permitem um direcionamento para confecção de barras considerando-se o diâmetro ósseo como referência.(AU)

Bone fractures can be corrected from external skeletal fixators (ESF) in a fairly common internal stabilization method, in which connector bars polymethylmethacrylate (PMMA) is used. PMMA is used without criterion of diameter, and it can break if it is too thin or too heavy. It can be uncomfortable when bulky. The aim of this study was to test, through biomechanical axial compression and bending which is the ideal connector bar diameter PMMA, correlated to bone diameter for use in type Ia ESF. Twenty-four humerus were used to make measurements of length, diameter, circumference, and biomechanical testing. After the bars confected with 1.5 times the average diameter of the bone (group I), the same diameter (group II) and 0.5 times the diameter of the bone (group III). With the obtained results, using GII and GIII results, it was observed that the connector bars in group II were more resistant than the bones in the compression test. In the bending test, the bones resisted flexion strength when compared to group III and the group II was 4.3 times more resistant than group III in the same mechanical test. The results allow a direction for making bars considering bone diameter as a reference.(AU)

Corpectomia lateral parcial para o tratamento de compressão ventral extradural crônica entre T9-T10 em um cão / Partial lateral corpectomy for treatment of chronic ventral extradural compression between T9-T10 in a dog

Objetivou-se relatar um caso de protrusão do disco intervertebral com localização atípica e descrever a técnica cirúrgica de corpectomia lateral parcial no tratamento da afecção em um cão. Um cão de sete anos de idade, macho, raça Pug, foi atendido com ataxia proprioceptiva dos membros pélvicos havia três meses, associada à doença do disco intervertebral entre a nona e 10ª vértebras torácicas. Após um mês de tratamento conservativo sem melhora, o paciente foi encaminhado para o tratamento cirúrgico, quando foi realizada corpectomia lateral parcial esquerda para descompressão da medula espinhal. Após a cirurgia, o paciente apresentou melhora considerável do quadro, sendo a técnica eficaz na remoção da compressão extradural, sem manipulação da medula espinhal ou outras complicações.(AU)

The aim of this study is to report a case of intervertebral disc protrusion with atypical location and describe the surgical technique of partial lateral corpectomy in the treatment of this disease in a dog. A dog, seven -years-old, male, Pug breed was attended with proprioceptive ataxia of the hind limbs for three months correlated with intervertebral disc disease between the 9th and 10th thoracic vertebrae. After a month of conservative treatment without improvements, the patient was referred for surgical treatment, which was performed as a partial left lateral corpectomy for decompression of the spinal cord. After surgery, the patient showed considerable improvement, this technique being shown to be effective in the removal of extradural compression, without manipulation of the spinal cord or other complications.(AU)

Moisture content on the mechanical behavior of crambe grains / Influência do teor de água no comportamento mecânico dos grãos de crambe

This study aimed to verify the influence of moisture content on the values of maximum compressive strength, proportional deformity modulus, elastic coefficients d, e, and f beyond the tangent values, and maximum grain drying of crambe (Crambe abyssinica Hochst) under compression in natural resting position. Crambe grains with moisture contents ranging from 0.1547 to 0.0482 decimal db were dried at 40°C and uniaxially compressed between two parallel plates in the natural rest position. The gravimetric method was used to monitor reduction in moisture content during drying (weight loss). It was concluded that the compression force required to deform the crambe grains decreases as the moisture content increases. The proportional deformity modulus increases as the deformation decreases, yielding values between (0.09-0.27)×102MPa. Sigmoidal model described by Taylor series adequately represents the compression resistance of crambe grains in the natural rest position with moisture content lower than 0.0813db.(AU)

Neste trabalho objetivou-se verificar a influência do teor de água nos valores da força máxima de compressão, módulo proporcional de deformidade, coeficientes elásticos d, e, f, além dos valores da tangente e secante máximas nos grãos de crambe (Crambe abyssinica Hochst), submetidos à compressão na posição natural de repouso. Os grãos de crambe, utilizados com teores de água entre 0,1547 e 0,0482 (decimal b.s.), foram secos nas temperaturas de 40°C e comprimidos uniaxialmente entre duas placas paralelas, na posição natural de repouso, cuja redução do teor de água ao longo da secagem foi acompanhada pelo método gravimétrico (perda de massa). A força de compressão necessária para deformar os grãos de crambe diminui com o aumento do teor de água. O módulo proporcional de deformidade aumenta com a redução da deformação, obtendo-se valores entre 0,09 e 0,27 (x 102MPa), em que o modelo sigmoidal, descrito por meio da série de Taylor, representa adequadamente a resistência dos grãos de crambe à compressão na posição natural de repouso, para os teores de água menores que 0,0813 (b.s.)(AU)

Ensaio biomecânico para determinação do diâmetro de barra conectora de polimetilmetacrilato em fixador esquelético externo tipo Ia no úmero de suínos / Biomechanical test to determination the diameter of the polymethylmethacrylate bar in external skeletal fixator type Ia in swine humerusi

Fraturas ósseas podem ser corrigidas com a utilização de fixadores esqueléticos externos (FEE), método de estabilização bastante comum. Para tanto, têm-se utilizado barras conectoras de polimetilmetacrilato (PMMA) sem critério de diâmetro, as quais podem quebrar, se ficarem muito delgadas, ou ocasionar incômodo, quando muito pesadas e volumosas. O objetivo deste trabalho foi testar, por meio de ensaio biomecânico de compressão axial e flexão, qual é o diâmetro ideal da barra conectora de PMMA, correlacionado com o diâmetro ósseo para utilização em FEE tipo Ia. Utilizaram-se 24 úmeros para se realizarem medidas de comprimento, diâmetro, circunferência e ensaios biomecânicos. Após, foram confeccionadas barras de 1,5 vezes a média do diâmetro ósseo (grupo I), do mesmo diâmetro ósseo (grupo II) e de 0,5 vezes o diâmetro (grupo III). Com os resultados obtidos ao se compararem os valores dos ossos com os dos grupos II e III, verificou-se que as barras conectoras do grupo II mostraram-se mais resistentes do que o tecido ósseo no ensaio de compressão. No ensaio de flexão, os ossos resistiram mais quando comparados aos grupos II e III, sendo 4,3 vezes mais resistentes do que o grupo III nesse mesmo ensaio mecânico. Os resultados permitem um direcionamento para confecção de barras considerando-se o diâmetro ósseo como referência.(AU)

Bone fractures can be corrected from external skeletal fixators (ESF) in a fairly common internal stabilization method, in which connector bars polymethylmethacrylate (PMMA) is used. PMMA is used without criterion of diameter, and it can break if it is too thin or too heavy. It can be uncomfortable when bulky. The aim of this study was to test, through biomechanical axial compression and bending which is the ideal connector bar diameter PMMA, correlated to bone diameter for use in type Ia ESF. Twenty-four humerus were used to make measurements of length, diameter, circumference, and biomechanical testing. After the bars confected with 1.5 times the average diameter of the bone (group I), the same diameter (group II) and 0.5 times the diameter of the bone (group III). With the obtained results, using GII and GIII results, it was observed that the connector bars in group II were more resistant than the bones in the compression test. In the bending test, the bones resisted flexion strength when compared to group III and the group II was 4.3 times more resistant than group III in the same mechanical test. The results allow a direction for making bars considering bone diameter as a reference.(AU)

Avaliação sensitiva, motora e cistométrica de cães com lesão medular crônica, submetidos ao transplante de células-tronco mesenquimais derivadas de tecido adiposo / Sensory, motor and cystometric evaluation of dogs with chronic spinal cord injury submitted to mesenchymal stem cell transplantation

A utilização de células-tronco na reparação de lesões tem sido extensivamente investigada. Neste estudo, examinamos os efeitos terapêuticos de dois transplantes (12x106 céls/transplante) de células-tronco mesenquimais alogênicas derivadas do tecido adiposo (CTDAs) em 11 cães com lesões crônicas traumáticas toracolombares da medula espinhal. As CTDAs foram foram cultivadas in vitro, a proliferação e a viabilidade foram avaliadas. As suspensões foram expandidas e administradas no espaço intradural com intervalo de uma semana entre transplantes. Os cães foram submetidos à avaliações clínicas, laboratoriais, radiográficas, tomográficas, sensitivas, motoras e cistométricas. A maioria dos animais não tinha raça definida (63,63%), mesma proporção para o acometimento de fêmeas e foi observada predominância de fratura com subluxação vertebral (81,81%). Na comparação dos cães pré e pós-transplante não foram observadas alterações hematológicas e três animais (27,27%) apresentaram cistite bacteriana. Em relação a sensibilidade, motricidade e cistometria, também não houve alterações significativas dos índices antes e pós transplantes, sendo observado a ausência nociceptiva na maioria dos animais (72,73%), paraplegia e incontinência urinária na mesma proporção. Neste estudo concluiu-se que o protocolo utilizado de transplante de CTDAs, demonstrou ser um tratamento seguro para cães com lesão medular crônica, com melhora discreta da funcionalidade vesical, porém sem melhora clínica significativa.(AU)

The use of stem cells in injury repair has been extensively investigated. In this study, we examined the therapeutic effects of two transplants (12x106 cells/transplantation) of allogenic adipose-derived stem cells (ASCs) in 11 dogs with chronic spinal cord injury. ASC were cultured in vitro, proliferation and cell viability were evaluated. Cell suspensions were prepared and administered in the intradural space, with a one-week interval between transplants. The animals were submitted to clinical, laboratory, radiographic, tomographic, sensory, motor and cystometric evaluations. Most of the animals were not a breed defined (63.63%), the same proportion for females affected, predominance of vertebral subluxation fracture was observed (81.81%). Before and after the transplants no hematological changes were observed, three animals (27.27%) presented bacterial cystitis, and in relation to motor, cystometry and sensitivity, no improvement was observed; the rates were maintained before and after transplants, predominance of nociceptive absence in most animals (72.73%), and paraplegia and urinary incontinence in the same proportion. In this study it was concluded that the use of ADSCs for the treatment of dogs with chronic spinal cord injury is safe, with a slight improvement in bladder function, but without significantly clinical improvement.(AU)

Avaliação sensitiva, motora e cistométrica de cães com lesão medular crônica, submetidos ao transplante de células-tronco mesenquimais derivadas de tecido adiposo / Sensory, motor and cystometric evaluation of dogs with chronic spinal cord injury submitted to mesenchymal stem cell transplantation

A utilização de células-tronco na reparação de lesões tem sido extensivamente investigada. Neste estudo, examinamos os efeitos terapêuticos de dois transplantes (12x106 céls/transplante) de células-tronco mesenquimais alogênicas derivadas do tecido adiposo (CTDAs) em 11 cães com lesões crônicas traumáticas toracolombares da medula espinhal. As CTDAs foram foram cultivadas in vitro, a proliferação e a viabilidade foram avaliadas. As suspensões foram expandidas e administradas no espaço intradural com intervalo de uma semana entre transplantes. Os cães foram submetidos à avaliações clínicas, laboratoriais, radiográficas, tomográficas, sensitivas, motoras e cistométricas. A maioria dos animais não tinha raça definida (63,63%), mesma proporção para o acometimento de fêmeas e foi observada predominância de fratura com subluxação vertebral (81,81%). Na comparação dos cães pré e pós-transplante não foram observadas alterações hematológicas e três animais (27,27%) apresentaram cistite bacteriana. Em relação a sensibilidade, motricidade e cistometria, também não houve alterações significativas dos índices antes e pós transplantes, sendo observado a ausência nociceptiva na maioria dos animais (72,73%), paraplegia e incontinência urinária na mesma proporção. Neste estudo concluiu-se que o protocolo utilizado de transplante de CTDAs, demonstrou ser um tratamento seguro para cães com lesão medular crônica, com melhora discreta da funcionalidade vesical, porém sem melhora clínica significativa.(AU)

The use of stem cells in injury repair has been extensively investigated. In this study, we examined the therapeutic effects of two transplants (12x106 cells/transplantation) of allogenic adipose-derived stem cells (ASCs) in 11 dogs with chronic spinal cord injury. ASC were cultured in vitro, proliferation and cell viability were evaluated. Cell suspensions were prepared and administered in the intradural space, with a one-week interval between transplants. The animals were submitted to clinical, laboratory, radiographic, tomographic, sensory, motor and cystometric evaluations. Most of the animals were not a breed defined (63.63%), the same proportion for females affected, predominance of vertebral subluxation fracture was observed (81.81%). Before and after the transplants no hematological changes were observed, three animals (27.27%) presented bacterial cystitis, and in relation to motor, cystometry and sensitivity, no improvement was observed; the rates were maintained before and after transplants, predominance of nociceptive absence in most animals (72.73%), and paraplegia and urinary incontinence in the same proportion. In this study it was concluded that the use of ADSCs for the treatment of dogs with chronic spinal cord injury is safe, with a slight improvement in bladder function, but without significantly clinical improvement.(AU)

A importância dos exames neurológico e radiográfico no diagnóstico de lesões cervicais em equino: relato de caso / Fundamentals of neurological and radiographic examination on diagnosis of cervical lesions of a horse: case report

As lesões vertebrais cervicais são relativamente comuns nos equinos. No entanto, são poucas as descrições a respeito desse tema na literatura. Acredita-se que esse fato se deva, em parte, às limitações relacionadas ao diagnóstico. Em virtude de um traumatismo cervical, o animal pode apresentar sinais clínicos de paresia e paraplegia até tetraparesia ou tetraplegia, que podem culminar em estado comatoso e, eventualmente, em morte. Esses sinais clínicos podem ser detectados no exame físico, porém, quando associado à imaginologia (avaliação radiográfica), permite a obtenção de diagnóstico mais preciso da lesão. Consequentemente, um prognóstico mais adequado pode ser estabelecido para o paciente. Em face do exposto, apresenta-se o caso de uma égua Mangalarga, de quatro anos de idade, com sinais de tetraplegia pós-trauma, aumento de tônus muscular e paralisia espástica, com hiperreflexia, nos quatros membros. Por meio dos exames neurológicos realizados na paciente, em associação com as imagens radiográficas convencionais e contrastadas, foi possível estabelecer o diagnóstico do quadro. O animal apresentava lesões envolvendo as duas primeiras vértebras cervicais, atlas (C1) e áxis (C2), e a quinta e a sexta vértebra (C5-C6), destacando fratura de C1, deslocamento do dente de C2 e subluxação entre C5 e C6, com compressão ventrodorsal da medula espinhal. Confirmadas as suspeitas neurológicas e mediante prognóstico desfavorável, o animal foi submetido à eutanásia, com consentimento do proprietário. As lesões observadas nas imagens radiográficas foram confrontadas e confirmadas na necropsia.(AU)

Cervical vertebral lesions are relatively common in equine patients, but its diagnosis seems challenging for the clinician. Clinical signs most commonly associated with this clinical feature are paresis, paraplegia, tetraparesis, tetraplegia, which may lead the patient to a comatose state, and even death. Fortunately, these clinical signs can be perceived during physical examination. All of which, alongside imaging techniques, may allow a precise diagnose of the location of lesions and prediction of a prognosis for the patient. We present a case report of a Mangalarga mare, with four years of age, presenting signs of post-traumatic tetraplegia with spastic paralysis with increased muscular tonus and hyperreflexia in all four limbs. A thorough neurological examination of the patient associated with conventional and contrast medium radiographic imaging of the cervical region identified lesions at the atlas (C1) and axis (C2, and fifth (C5) and sixth (C6) cervical vertebrae. Fracture of the atlas vertebrae, dislocation of the axis' dens as well as subluxation of C5-C6 causing ventrodorsal medullary compression of the spinal cord were diagnosed radiographically. Due to the extent of the lesions the animal was euthanatized with the owner's consent. All lesions identified radiographically were posteriorly confirmed during post-mortem examination.(AU)

A importância dos exames neurológico e radiográfico no diagnóstico de lesões cervicais em equino: relato de caso

ABSTRACT Cervical vertebral lesions are relatively common in equine patients, but its diagnosis seems challenging for the clinician. Clinical signs most commonly associated with this clinical feature are paresis, paraplegia, tetraparesis, tetraplegia, which may lead the patient to a comatose state, and even death. Fortunately, these clinical signs can be perceived during physical examination. All of which, alongside imaging techniques, may allow a precise diagnose of the location of lesions and prediction of a prognosis for the patient. We present a case report of a Mangalarga mare, with four years of age, presenting signs of post-traumatic tetraplegia with spastic paralysis with increased muscular tonus and hyperreflexia in all four limbs. A thorough neurological examination of the patient associated with conventional and contrast medium radiographic imaging of the cervical region identified lesions at the atlas (C1) and axis (C2, and fifth (C5) and sixth (C6) cervical vertebrae. Fracture of the atlas vertebrae, dislocation of the axis dens as well as subluxation of C5-C6 causing ventrodorsal medullary compression of the spinal cord were diagnosed radiographically. Due to the extent of the lesions the animal was euthanatized with the owners consent. All lesions identified radiographically were posteriorly confirmed during post-mortem examination.

RESUMO As lesões vertebrais cervicais são relativamente comuns nos equinos. No entanto, são poucas as descrições a respeito desse tema na literatura. Acredita-se que esse fato se deva, em parte, às limitações relacionadas ao diagnóstico. Em virtude de um traumatismo cervical, o animal pode apresentar sinais clínicos de paresia e paraplegia até tetraparesia ou tetraplegia, que podem culminar em estado comatoso e, eventualmente, em morte. Esses sinais clínicos podem ser detectados no exame físico, porém, quando associado à imaginologia (avaliação radiográfica), permite a obtenção de diagnóstico mais preciso da lesão. Consequentemente, um prognóstico mais adequado pode ser estabelecido para o paciente. Em face do exposto, apresenta-se o caso de uma égua Mangalarga, de quatro anos de idade, com sinais de tetraplegia pós-trauma, aumento de tônus muscular e paralisia espástica, com hiperreflexia, nos quatros membros. Por meio dos exames neurológicos realizados na paciente, em associação com as imagens radiográficas convencionais e contrastadas, foi possível estabelecer o diagnóstico do quadro. O animal apresentava lesões envolvendo as duas primeiras vértebras cervicais, atlas (C1) e áxis (C2), e a quinta e a sexta vértebra (C5-C6), destacando fratura de C1, deslocamento do dente de C2 e subluxação entre C5 e C6, com compressão ventrodorsal da medula espinhal. Confirmadas as suspeitas neurológicas e mediante prognóstico desfavorável, o animal foi submetido à eutanásia, com consentimento do proprietário. As lesões observadas nas imagens radiográficas foram confrontadas e confirmadas na necropsia.

A importância dos exames neurológico e radiográfico no diagnóstico de lesões cervicais em equino: relato de caso / Fundamentals of neurological and radiographic examination on diagnosis of cervical lesions of a horse: case report

As lesões vertebrais cervicais são relativamente comuns nos equinos. No entanto, são poucas as descrições a respeito desse tema na literatura. Acredita-se que esse fato se deva, em parte, às limitações relacionadas ao diagnóstico. Em virtude de um traumatismo cervical, o animal pode apresentar sinais clínicos de paresia e paraplegia até tetraparesia ou tetraplegia, que podem culminar em estado comatoso e, eventualmente, em morte. Esses sinais clínicos podem ser detectados no exame físico, porém, quando associado à imaginologia (avaliação radiográfica), permite a obtenção de diagnóstico mais preciso da lesão. Consequentemente, um prognóstico mais adequado pode ser estabelecido para o paciente. Em face do exposto, apresenta-se o caso de uma égua Mangalarga, de quatro anos de idade, com sinais de tetraplegia pós-trauma, aumento de tônus muscular e paralisia espástica, com hiperreflexia, nos quatros membros. Por meio dos exames neurológicos realizados na paciente, em associação com as imagens radiográficas convencionais e contrastadas, foi possível estabelecer o diagnóstico do quadro. O animal apresentava lesões envolvendo as duas primeiras vértebras cervicais, atlas (C1) e áxis (C2), e a quinta e a sexta vértebra (C5-C6), destacando fratura de C1, deslocamento do dente de C2 e subluxação entre C5 e C6, com compressão ventrodorsal da medula espinhal. Confirmadas as suspeitas neurológicas e mediante prognóstico desfavorável, o animal foi submetido à eutanásia, com consentimento do proprietário. As lesões observadas nas imagens radiográficas foram confrontadas e confirmadas na necropsia.(AU)

Cervical vertebral lesions are relatively common in equine patients, but its diagnosis seems challenging for the clinician. Clinical signs most commonly associated with this clinical feature are paresis, paraplegia, tetraparesis, tetraplegia, which may lead the patient to a comatose state, and even death. Fortunately, these clinical signs can be perceived during physical examination. All of which, alongside imaging techniques, may allow a precise diagnose of the location of lesions and prediction of a prognosis for the patient. We present a case report of a Mangalarga mare, with four years of age, presenting signs of post-traumatic tetraplegia with spastic paralysis with increased muscular tonus and hyperreflexia in all four limbs. A thorough neurological examination of the patient associated with conventional and contrast medium radiographic imaging of the cervical region identified lesions at the atlas (C1) and axis (C2, and fifth (C5) and sixth (C6) cervical vertebrae. Fracture of the atlas vertebrae, dislocation of the axis' dens as well as subluxation of C5-C6 causing ventrodorsal medullary compression of the spinal cord were diagnosed radiographically. Due to the extent of the lesions the animal was euthanatized with the owner's consent. All lesions identified radiographically were posteriorly confirmed during post-mortem examination.(AU)

Estudo comparativo da resistência mecânica da força de compressão entre biomateriais naturais, sintéticos e mistos / Comparative study of mechanical strength of compression between natural, synthetic and mixed biomaterials

As afecções ortopédicas com perda de tecido ósseo são um desafio tanto na medicina veterinária quanto na medicina humana. Portanto, não é raro ortopedistas se depararem com fraturas cominutivas irredutíveis de ossos longos, neoplasias ósseas ou não-uniões, que necessitam de procedimentos cirúrgicos reparadores, por meio da substituição de segmento ou preenchimento de falha óssea com o uso de biomateriais. Pretende-se com esta pesquisa avaliar e comparar a resistência mecânica entre biomateriais naturais, sintéticos e mistos. Foram utilizados sete grupos experimentais compostos por seis corpos de provas cada: Grupo 1 , tecido ósseo cortical de coelho (OSSO - controle); Grupo 2, cimento ósseo (CO); Grupo 3, cimento ósseo autoclavado (COA); Grupo 4, cimento ósseo e macrofragmento ósseo cortical de cão (COMaFO); Grupo 5, cimento ósseo e macrofragmento ósseo autoclavado de cortical de cão (COMaFOA); Grupo 6, cimento ósseo e microfragmento ósseo cortical de cão (COMiFO) e Grupo 7, cimento ósseo e microfragmento ósseo cortical de cão (COMiFOA). Os corpos de prova foram submetidos a ensaios mecânicos de compressão axial controlada em máquina universal de ensaio Emic®. O teste era interrompido quando ocorria queda brusca na curva do gráfico indicando falência da amostra. Em relação à Força máxima, os grupos COA, COMaFOA e COMiFOA não diferiram estatisticamente do grupo controle (OSSO; p>0,01). Já os grupos CO, COMaFO e COMiFO diferiram estatisticamente do grupo controle (OSSO; p<0,01). Quanto a rigidez relativa, os grupos COMaFOA e COMiFOA não diferiram estatisticamente do grupo controle (OSSO; p>0,01). Já os grupos CO, COA, COMaFO e COMiFO diferiram estatisticamente do grupo controle (OSSO; p<0,01). Comparando a deformação, os grupos COMaFo, COMaFOA e COMiFO não diferiram estatisticamente do grupo controle (OSSO; p>0,01). Já os grupos CO, COA e COMiFOA diferiram estatisticamente do grupo controle (OSSO; p<0,01). Conclui-se que apenas os grupos COMaFOA e COMiFOA apresentaram propriedades mecânicas muito semelhantes às do grupo controle (OSSO). Por isso, devido a essas características, esses dois biomateriais (COMaFOA e COMiFOA) seriam os mais indicados como substitutos na reparação de falhas ósseas.(AU)

The orthopedic diseases with bone loss are the challenge in both veterinary and human medicine. Therefore, the orthopedist commonly deal with irreducible comminuted fractures of long bones, bone tumors or non-unions, which require repairers surgical procedures, through the segment replacement or bone defect filling with biomaterials. The aim of this research is to evaluate and compare the mechanical strength of natural, synthetic and mixed biomaterials. Seven experimental groups of six test samples each were used: Group 1 rabbit cortical bone (BONE - control); Group 2, bone cement (CO); Group 3, bone cement autoclaved (COA); Group 4, bone cement and dog cortical bone macrofragment (COMaFO); Group 5, bone cement and bone autoclaved macrofragment dog cortical (COMaFOA); Group 6, bone cement and dog cortical bone microfragment (COMIFO) and Group 7, bone cement and dog cortical bone microfragment (COMiFOA). The specimens were subjected to axial compression mechanical tests controlled universal testing machine EMIC®. The test was stopped when there was sharp decline in the graph curve indicating failure of the sample. In relation to the maximum force, the COA groups COMaFOA and COMiFOA not statistically different from the control group (BONE; p> 0.01). Already the CO groups, COMaFO and COMIFO difeririram statistically the control group (BONE; p <0.01). The relative rigidity, the COMaFOA and COMiFOA groups did not differ statistically from the control group (BONE; p>0.01). Already the CO groups, COA, COMaFO and COMIFO differed significantly from the control group (BONE; p<0.01). Comparing the deformation, the COMaFo groups COMaFOA and COMIFO not statistically different from the control group (BONE; p>0.01). Already the CO groups, COA and COMiFOA differed significantly from the control group (BONE; p<0.01). It is concluded that only COMaFOA and COMiFOA groups showed very similar mechanical properties to the control group (BONE). Therefore, due to these characteristics, these two biomaterials (COMaFOA e COMiFOA) would be the most suitable as a substitute in the repair of bone defects.(AU)