Tibial plateau leveling osteotomy in dogs: an ex vivo comparative study of knee's surrounding structures protection methods

Background: Cranial cruciate ligament failure is one of the leading causes of pelvic limb lameness in dogs and one of the most recommended treatments is tibial plateau leveling osteotomy (TPLO) surgery. However, this procedure may lead to some complications as fractures of the fibula, laceration in varying degrees of the popliteal vasculature and its branches, neuropraxia, neurotmeses, among others. The goals of this study were to compare the effectiveness of 8 methods used during TPLO, to prevent damage to the cranial tibial artery, fibula, tibial and fibular nerve (surgical compresses, specific surgical retractors I and II and an osteotomy technique variation). Materials, Methods & Results: A total of 40 canine cadavers weighing 25.9 ± 3.7 kg were submitted to TPLO. Animals were previously prepared with 1: 4 barium red latex solution, to provide radiopacity of arteries surrounding the knee (n = 80). TPLO was performed using 8 methods to protect the cranial tibial artery, fibula, and tibial and fibular nerves. Each method was used in one of the knees of 5 animals. The contralateral knee was maintained as a control (without protection). The knees were radiographed in orthogonal projections before and after the osteotomies and then anatomically dissected. The evaluated structures were photographed, and the images sent to four blind evaluators (visual macroscopy) to classify the possible injuries. The highest incidence of injuries was identified when protection methods were used. However, this difference was not significant (P > 0.05). No significant differences regarding efficacy were found between all 8 protection methods. Discussion: In this study, the total incidence of injuries following TPLO was 20% was much higher than that presented in the literature which indicates when considering only intraoperative injuries. The dogs cadavers tissue resistance and stiffened latex may have predisposed the osteotomy injury, as soft tissues with greater flexibility are less susceptible to trauma caused by the oscillatory saw. When compared to others cadaveric studies that also evaluated the efficacy of surgical dressings to protect the cranial tibial artery, during TPLO, we also find a higher incidence of damage. Maybe the limb's position was responsible for this difference, once in the after mentioned researches the limb was positioned suspended to simulate a dorsal decubitus position and we choose the limb position with the lateral face resting on the surface of the operating table, and this may have provided extra pressure from the structures towards the osteotomy saw, increasing the occurrence of those damages. Although the present study did not reveal a significant difference for the use of protection methods, we believe that the dimensions of the compresses used herein may have contributed to a higher incidence of injuries. They probably increased the tissue trauma needed for their allocation and led to a lower positioning accuracy for the isolation of these structures. Maybe for the same reason, the specific type II surgical retractor was the only shield that, observationally, did not increase the occurrence of injuries, once less dissection was required to allocate it. The difference in geometric dimensions between the retractors may justify the superiority of the retractor II, since it allows a more careful and apparently less traumatic allocation. Performing TPLO without adopting these protection methods did not lead to a higher risk of injury to the cranial tibial artery, fibula, and tibial and fibular nerves.

Canal flare index evaluation for different dog breeds / Avaliação do canal flare index femoral de diferentes raças de cães

This study determined the canal flare index (CFI) of four dog breeds using two distinct femoral regions as a reference. Thirty-five radiographs of the hip joints of Golden Retrievers (GRG), German Shepherds (GSG), Labrador Retrievers (LRG), and Rottweilers (RG) of both sexes were used. Seventy experimental units were submitted to CFI calculation. Objective (CFIob) and subjective (CFIsub) values of the CFI of each experimental unit were determined according to the anatomical reference used for the calculation. A significant difference in the CFIob between the Golden Retriever and German Shepherd breeds (1.68 ± 0.16 and 1.49 ± 0.08), and in the CFIsub between Golden Retriever, German Shepherd, and Rottweiler breeds (2.09 ± 0.31, 1.86 ± 0.11, and 1.84 ± 0.18) was reported. The subjective form of measurement showed higher values than the objective form (GRG: 2.09 ± 0.31; GSG: 1.86 ± 0.11; LRG: 2.07 ± 0.12; RG: 1.84 ± 0.18). The CFI values of each breed were similar, suggesting a certain racial pattern. A significant difference in the interobserver assessment for both CFIsub and CFIob, in all races was observed. The CFI analysis identified morphological patterns of the proximal femur in the different races. Results indicated the need for standardization of the anatomical references used to calculate the CFI because there were statistical differences among the measurements among the observers.(AU)

Objetivou-se determinar o canal flare index (CFI) de quatro raças específicas de cães, utilizando-se duas regiões femorais distintas como referência. Foram analisadas 35 radiografias de articulações coxofemorais de cães das raças Golden Retriever (GGR), Pastor Alemão (GPA), Labrador Retriever (GLR) e Rottweiler (GR), de ambos os sexos, configurando 70 unidades experimentais submetidas ao cálculo do CFI. Determinaram-se os valores objetivo (CFIob) e subjetivo (CFIsub) do CFI de cada unidade experimental de acordo com a referência anatômica utilizada para o cálculo. Houve diferença significativa do CFIob entre as raças Golden Retriever e Pastor Alemão (1,68 ± 0,16 e 1,49 ± 0,08), e do CFIsub entre as raças Golden Retriever, Pastor Alemão e Rottweiler (2,09 ± 0,31, 1,86 ± 0,11 e 1,84 ± 0,18). A forma subjetiva de mensuração apresentou valores maiores que a forma objetiva (GGR: 2,09 ± 0,31; GPA: 1,86 ± 0,11; GLR: 2,07 ± 0,12; GR: 1,84 ± 0,18). Os valores de CFI de cada raça se apresentaram similares, sugerindo haver determinado padrão racial. Houve diferença significativa na avaliação interobservadores, tanto do CFIsub quanto CFIob, em todas as raças. A análise do CFI identificou padrões morfológicos do fêmur proximal nas diferentes raças. Os resultados indicaram a necessidade de padronização dos referenciais anatômicos utilizados para o cálculo do CFI, uma vez que houve relevância estatística entre as diferentes mensurações entre os observadores.(AU)

Uso de técnica adaptada para cavotomia em cão com feocromocitoma associado a trombo neoplásico / Adapted cavotomy technique for pheochromocytoma associated tumor thrombi in a dog

Background: In dogs pheochromocytoma usually compress and invade into the adjacent vessels and structures, whichmay lead to the occurrence of caudal vena caval tumor thrombi. The surgical approach in these cases requires adrenalectomy with caval thrombectomy. Conventionally, tourniquets and partial occlusion clamp are used to reduce intraoperativeblood loss, but in dogs with a large thrombus associated to a great local tumor invasion, the traditional technique may behindered. The aim of this study was to report the use of a purse-string suture during venotomy of the caudal vena cava forthrombectomy, as an alternative to tourniquet and partial occlusion clamp.Case: An 11-year-old male Daschound breed dog, was referred for evaluation because of the appearance of small blackenednodules in the ventral abdomen. During a search for metastatic lesions with abdominal ultrasound, the right adrenal wasidentified with significant volume increase, and presence of tumor-associate circular formation that appeared to invade thecaudal vena cava, suggestive of neoplastic invasion or thrombus. Abdominal computed tomography showed caudal venacava in its hepatic portion presenting considerable increase in diameter, with caudal dilation and presence of hypoattenuatingmaterial in its lumen. Right adrenal gland with rounded appearance and regular borders, heterogeneous parenchyma andjuxtaposed caudal vena cava suggesting invasion of this, confirming the sonographic findings. During exploratory celiotomy,adherence of the adrenal mass to the right renal vessels and invasion of the caudal vena cava were observed, leading to theneed of nephrectomy and venotomy for thrombectomy. To perform the venotomy, a Rumel tourniquet was placed looselyaround the vena cava only caudal to the invasion point of the tumor thrombus, cranially, tourniquet application was notpossible due to the presence of a large thrombus extending into the intrahepatic cava...

Uso de técnica adaptada para cavotomia em cão com feocromocitoma associado a trombo neoplásico / Adapted cavotomy technique for pheochromocytoma associated tumor thrombi in a dog

Background: In dogs pheochromocytoma usually compress and invade into the adjacent vessels and structures, whichmay lead to the occurrence of caudal vena caval tumor thrombi. The surgical approach in these cases requires adrenalectomy with caval thrombectomy. Conventionally, tourniquets and partial occlusion clamp are used to reduce intraoperativeblood loss, but in dogs with a large thrombus associated to a great local tumor invasion, the traditional technique may behindered. The aim of this study was to report the use of a purse-string suture during venotomy of the caudal vena cava forthrombectomy, as an alternative to tourniquet and partial occlusion clamp.Case: An 11-year-old male Daschound breed dog, was referred for evaluation because of the appearance of small blackenednodules in the ventral abdomen. During a search for metastatic lesions with abdominal ultrasound, the right adrenal wasidentified with significant volume increase, and presence of tumor-associate circular formation that appeared to invade thecaudal vena cava, suggestive of neoplastic invasion or thrombus. Abdominal computed tomography showed caudal venacava in its hepatic portion presenting considerable increase in diameter, with caudal dilation and presence of hypoattenuatingmaterial in its lumen. Right adrenal gland with rounded appearance and regular borders, heterogeneous parenchyma andjuxtaposed caudal vena cava suggesting invasion of this, confirming the sonographic findings. During exploratory celiotomy,adherence of the adrenal mass to the right renal vessels and invasion of the caudal vena cava were observed, leading to theneed of nephrectomy and venotomy for thrombectomy. To perform the venotomy, a Rumel tourniquet was placed looselyaround the vena cava only caudal to the invasion point of the tumor thrombus, cranially, tourniquet application was notpossible due to the presence of a large thrombus extending into the intrahepatic cava...(AU)

Comparação clínica entre dois métodos de estabilização em desvio angular distal de tíbia corrigido pela metodologia CORA / Clinical comparison between two stabilization methods in distal tibial angular deviation corrected by the CORA method

Background: Angular deformity is characterized by the deviation of part of the bone that can occur in three different planes, frontal, sagittal and transverse. Trauma on physeal plates is the most common cause of angular deviations of the limbs in dogs. Currently the CORA (Center of Rotation of Angulation) methodology is the best way to evaluate and surgically correct these deformities. The objective of this study is to describe the surgical procedures performed to treat the uniapical valgus deviation affecting both tibial bones in a dog, comparing the outcomes of hybrid external skeletal fixator used in the right pelvic limb in relation to the locking plate used in the left pelvic limb. Case: A 10-month old Border Collie dog was attended at the University Veterinary Hospital with history of lameness and deviation of both pelvic limbs. In the orthopedic examination, it was possible to identify bilateral valgus deviation in the region of the tibio-tarsal joints and moderate lameness, with absence of pain or joint crepitation. Radiographic examination showed that the deformity was only uniapical in the frontal plane, affecting both tibial bones of the dog. Signs of osteoarthrosis were not observed and the preoperative examinations were within the normal limits for the species. The deformities were corrected in two surgical times starting with the procedure in the right tibia, which appeared to be clinically worse. Due to the fact that it was a bilateral affection and there was not a healthy pelvic limb to obtain the normal angles values of this dog, for planning according to the CORA methodology, the values of the tibial mechanical angles for dogs of similar size were taken from the literature. For surgical correction of the right tibia, a closed wedge osteotomy was performed following the second rule of Paley

Comparação clínica entre dois métodos de estabilização em desvio angular distal de tíbia corrigido pela metodologia CORA / Clinical comparison between two stabilization methods in distal tibial angular deviation corrected by the CORA method

Background: Angular deformity is characterized by the deviation of part of the bone that can occur in three different planes, frontal, sagittal and transverse. Trauma on physeal plates is the most common cause of angular deviations of the limbs in dogs. Currently the CORA (Center of Rotation of Angulation) methodology is the best way to evaluate and surgically correct these deformities. The objective of this study is to describe the surgical procedures performed to treat the uniapical valgus deviation affecting both tibial bones in a dog, comparing the outcomes of hybrid external skeletal fixator used in the right pelvic limb in relation to the locking plate used in the left pelvic limb. Case: A 10-month old Border Collie dog was attended at the University Veterinary Hospital with history of lameness and deviation of both pelvic limbs. In the orthopedic examination, it was possible to identify bilateral valgus deviation in the region of the tibio-tarsal joints and moderate lameness, with absence of pain or joint crepitation. Radiographic examination showed that the deformity was only uniapical in the frontal plane, affecting both tibial bones of the dog. Signs of osteoarthrosis were not observed and the preoperative examinations were within the normal limits for the species. The deformities were corrected in two surgical times starting with the procedure in the right tibia, which appeared to be clinically worse. Due to the fact that it was a bilateral affection and there was not a healthy pelvic limb to obtain the normal angles values of this dog, for planning according to the CORA methodology, the values of the tibial mechanical angles for dogs of similar size were taken from the literature. For surgical correction of the right tibia, a closed wedge osteotomy was performed following the second rule of Paley…(AU)

Pantarsal arthrodesis with a customized titanium medial plate in a dog

Background: Tibiotarsal joint luxations are mostly traumatic and due to automobile accidents. The arthrodesis of this joint is considered the final solution for trauma with ligament lesions without repair, luxations without possibility of joint recovery and chronic joint diseases. The direction to which the joint is dislocated is associated with the forces of trauma, and bilateral ligament injuries are not uncommon. However, the medial ligaments are more frequently injured. The aim of this study is to describe the performance of pantarsal arthrodesis using a customized titanium plate for application to the medial surface of the joint.Case: An undefined breed dog, weighing 21.5 kg, was attended at the Veterinary Hospital of the Federal University of Lavras (UFLA) with history of trauma and injury in the right pelvic limb. After physical and radiographic examinations it was diagnosed with an exposed luxation of the tibiotarsal joint and tissue loss in the region. The tibiotarsal region was cleaned and a bandage was made daily until the first surgical procedure, which occurred five days later. Initially, it was treated without success with the use of a transarticular external fixator1 . Subsequently, pantarsal arthrodesis was performed using a customized titanium angled plate (Made by a private manufacturer based on the functional angulation of the tibiotarsal joint of the contralateral limb). The joint was accessed for exposure of the distal portion of the tibia, tarsal and metatarsals bones. Wear of the articular surfaces was performed and then the customized angulation plate for pantarsal arthrodesis was placed on the medial side of the joint. Bicortical drillings were performed, starting with the proximal orifice. According to the holes of the plate, five 3.5 mm diameter screws1 (four at the distal tibia and one at the tarsus) and four 2.7 mm diameter screws were used in the metatarsal bones.[...](AU)

Pantarsal arthrodesis with a customized titanium medial plate in a dog

Background: Tibiotarsal joint luxations are mostly traumatic and due to automobile accidents. The arthrodesis of this joint is considered the final solution for trauma with ligament lesions without repair, luxations without possibility of joint recovery and chronic joint diseases. The direction to which the joint is dislocated is associated with the forces of trauma, and bilateral ligament injuries are not uncommon. However, the medial ligaments are more frequently injured. The aim of this study is to describe the performance of pantarsal arthrodesis using a customized titanium plate for application to the medial surface of the joint.Case: An undefined breed dog, weighing 21.5 kg, was attended at the Veterinary Hospital of the Federal University of Lavras (UFLA) with history of trauma and injury in the right pelvic limb. After physical and radiographic examinations it was diagnosed with an exposed luxation of the tibiotarsal joint and tissue loss in the region. The tibiotarsal region was cleaned and a bandage was made daily until the first surgical procedure, which occurred five days later. Initially, it was treated without success with the use of a transarticular external fixator1 . Subsequently, pantarsal arthrodesis was performed using a customized titanium angled plate (Made by a private manufacturer based on the functional angulation of the tibiotarsal joint of the contralateral limb). The joint was accessed for exposure of the distal portion of the tibia, tarsal and metatarsals bones. Wear of the articular surfaces was performed and then the customized angulation plate for pantarsal arthrodesis was placed on the medial side of the joint. Bicortical drillings were performed, starting with the proximal orifice. According to the holes of the plate, five 3.5 mm diameter screws1 (four at the distal tibia and one at the tarsus) and four 2.7 mm diameter screws were used in the metatarsal bones.[...]

Condrossarcoma em gradil costal de cão: relato de caso / Chondrosarcoma in grating costal in a dog a case report / Condrosarcoma en costal rejilla en un perro - un informe del caso

O condrossarcoma é uma neoplasia maligna, de origem mesenquimal, cujas células neoplásicas produzem uma matriz cartilaginosa, não osteoide ou diretamente óssea. O diagnóstico pode ser auxiliado por meio de métodos imaginológicos, porém apenas a histopatologia é definitivo. O presente relato descreve o caso de um cão sem padrão racial definido, com sete anos de idade, o qual apresentou um aumento de volume com cerca de 6,0 x 5,0 x 4,0 cm na região do hemitórax esquerdo, o qual segundo o proprietário estava presente há dois meses. Após a histopatologia, foi realizado o diagnóstico de condrossarcoma, porém o proprietário não procedeu com o tratamento instituído e o animal retornou a clínica 11 meses após o primeiro incidente em sofrimento irreversível. Objetiva-se descrever os aspectos macro e microscópico da respectiva neoplasia.(AU)

Chondrosarcoma is a malignant tumor of mesenchymal origin, which the neoplastic cells produce a cartilage matrix, no osteoid or bone directly. Diagnosis can be aided by imaginological methods, but only histopathology is definitive. This report describes the case of a mongrel dog, seven years old, with a volume increase of about 6,0 x 5,0 x 4,0 cm in the left hemithorax, which according to the owner there was two months ago. Histopathology after the diagnosis of chondrosarcoma was made and treatment instituted, but as the owner lost the thread it was not performed and the animal returned to clinical 11 months after the first incident irreversible suffering. Objective is to describe the macro and microscopic aspects of the neoplasm.(AU)

El condrosarcoma es un tumor maligno de origen mesenquimal, cuyas células neoplásicas producir una matriz de cartílago, no osteoide o hueso directamente. El diagnóstico puede ser assistido por métodos de imagen, pero sólo la histología esdefinitiva. Este informe describe el caso de un perro sin raza definida, de siete anos, con un aumento de volumen de alrededor de 6,0 x 5,0 x 4,0 cm en el hemitórax izquierdo, que según el propietario estaba allí hace dos meses. Después se realizó el diagnóstico histopatológico de condrosarcoma y el tratamiento instituido, pero como el propietario pierde el hilo no se hizo y el animal volvió a clínicas 11 meses después del primer incidente en el sufrimiento irreversible. Su objetivo es describir los aspectos macroscópicos y microscópicos de su neoplasia.(AU)

Condrossarcoma em gradil costal de cão: relato de caso / Chondrosarcoma in grating costal in a dog – a case report / Condrosarcoma en costal rejilla en un perro - un informe del caso

O condrossarcoma é uma neoplasia maligna, de origem mesenquimal, cujas células neoplásicas produzem uma matriz cartilaginosa, não osteoide ou diretamente óssea. O diagnóstico pode ser auxiliado por meio de métodos imaginológicos, porém apenas a histopatologia é definitivo. O presente relato descreve o caso de um cão sem padrão racial definido, com sete anos de idade, o qual apresentou um aumento de volume com cerca de 6,0 x 5,0 x 4,0 cm na região do hemitórax esquerdo, o qual segundo o proprietário estava presente há dois meses. Após a histopatologia, foi realizado o diagnóstico de condrossarcoma, porém o proprietário não procedeu com o tratamento instituído e o animal retornou a clínica 11 meses após o primeiro incidente em sofrimento irreversível. Objetiva-se descrever os aspectos macro e microscópico da respectiva neoplasia.

Chondrosarcoma is a malignant tumor of mesenchymal origin, which the neoplastic cells produce a cartilage matrix, no osteoid or bone directly. Diagnosis can be aided by imaginological methods, but only histopathology is definitive. This report describes the case of a mongrel dog, seven years old, with a volume increase of about 6,0 x 5,0 x 4,0 cm in the left hemithorax, which according to the owner there was two months ago. Histopathology after the diagnosis of chondrosarcoma was made and treatment instituted, but as the owner lost the thread it was not performed and the animal returned to clinical 11 months after the first incident irreversible suffering. Objective is to describe the macro and microscopic aspects of the neoplasm.

El condrosarcoma es un tumor maligno de origen mesenquimal, cuyas células neoplásicas producir una matriz de cartílago, no osteoide o hueso directamente. El diagnóstico puede ser assistido por métodos de imagen, pero sólo la histología esdefinitiva. Este informe describe el caso de un perro sin raza definida, de siete anos, con un aumento de volumen de alrededor de 6,0 x 5,0 x 4,0 cm en el hemitórax izquierdo, que según el propietario estaba allí hace dos meses. Después se realizó el diagnóstico histopatológico de condrosarcoma y el tratamiento instituido, pero como el propietario pierde el hilo no se hizo y el animal volvió a clínicas 11 meses después del primer incidente en el sufrimiento irreversible. Su objetivo es describir los aspectos macroscópicos y microscópicos de su neoplasia.