Finite element analysis of a new intervertebral disc prosthesis developed for the canine cervical spine / Elementos finitos de uma nova prótese de disco intervertebral desenvolvida para a coluna cervical canina

ABSTRACT: Cervical spondylomyelopathy (CSM) is a disease that affects mostly large- and giant-breed dogs. It is characterized by abnormalities of the cervical spine that may cause damage to the spinal cord and nerve roots. Cervical disc arthroplasty has been proposed as a treatment option in veterinary medicine. The current study evaluated the main stresses in a novel canine vertebral disc prosthesis and vertebral bodies using finite element analysis. Two experimental groups were created based on the material used for the prosthesis: stainless steel group (SSG) and titanium alloy group (TAG). Vertebral and prosthetic average equivalents von-Mises stress (VMS) and minimum principal stress (MiPS) were assessed while compressive, tensile, and lateral bending shear loads were applied. The stainless steel group had greater VMS distribution on all the evaluated parameters while the titanium alloy group had greater MiPS. Stresses were more concentrated on the lateral and ventral surfaces of the vertebral bodies than on their endplates. The average prosthetic stresses were more concentrated on the bone/implant contact surface than on the prosthesis/screw interface. Maximum stresses were concentrated in the screws' cranial surface. The novel prosthesis allows even distribution along the vertebral body. Comparing prosthesis materials, titanium alloy was marginally superior regarding average stresses in all directions and should be less likely to suffer subsidence.

RESUMO: Espondilomielopatia cervical (EMC) é uma doença que geralmente afeta cães de raças grandes e gigantes. Ela é caracterizada por anormalidades da coluna cervical que podem causar danos à medula espinhal ou às raízes nervosas. Artroplastia cervical com prótese de disco tem sido proposta como opção de tratamento na medicina veterinária. O presente estudo teve como objetivo avaliar os principais estresses em uma nova prótese de disco intervertebral canina e corpos vertebrais por meio da análise de elementos finitos. Foram compostos dois grupos experimentais que representaram o material constituinte da nova prótese: grupos aço inoxidável (SSG) e o liga de titânio (TAG). Tensões equivalente de von-Mises (VMS) e tensão principal mínima (MiPS) média foram avaliadas sob forças de compressão, tração e torção para vértebras e prótese. O grupo SSG teve maior distribuição de VMS para todos parâmetros avaliados, enquanto o grupo TAG teve maior MiPS. Estresses estiveram mais concentrados nas superfícies lateral e ventral dos corpos vertebrais do que nas placas terminais. Os estresses médios da prótese foram mais concentrados na superfície de contato osso/implante do que na interface prótese/parafuso. Estresses máximos foram concentrados na superfície cranial do parafuso. A nova prótese permitiu distribuição uniforme do estresse ao longo do corpo vertebral. Comparando os materiais da prótese, a liga de titânio foi marginalmente superior quanto aos estresses médios em todas as direções, sendo menos provável que sofra afundamento da prótese.

Tratamento de tromboembolismo e preparo para implantação de prótese osteointegrada com oxigenioterapia hiperbárica em uma gata / Treatment of tromboembolism and preparation for an osseointegrated prothesis fixation with hyperbaric oxygen therapy in a kitten

Background: Ischemic neuromyopathy is the most common reason for amputation in cats. In veterinary medicine, the use of prosthetic limbs is not widespread; therefore, in most cases total limb amputation is indicated. However, hyperbaric oxygen therapy (HBOT) is an alternative with several benefits for the treatment of vascular disorders with reperfusion, ischemia, and infection. Therefore, this study aimed to report the positive effects of HBOT on the treatment of ischemic neuromyopathy secondary to arterial thromboembolism on the patient's clinical improvement, and on the preparation of the patient for insertion of an osseointegrated prosthesis. Case: A 6-month-old mixed-breed kitten returned for treatment after undergoing surgery seven days earlier for reduction of traumatic diaphragmatic hernia, during which it suffered a cardiorespiratory arrest. The patient presented with acute pelvic limb paralysis with 24-h evolution, absent femoral pulse, plantar cushions and dorsal part of the limbs cold and pale. After supportive therapy and diagnosis of aortic thromboembolism by arterial Doppler, the patient started adjunctive treatment with HBOT from the first day of hospitalization. Sessions took place in an exclusive hyperbaric chamber for animals and lasted 60 min at a pressure of 2.5 absolute atmospheres and 100% oxygen, initially every 12 h. However, during the first 5 days of hospitalization, the distal region of both pelvic limbs began to show tissue devitalization and edema, and hematologic parameters showed changes on the 7th day. The right pelvic limb (RPL) showed more involvement of superficial tissues, extending to the tarsometatarsal joint region. After 8 days of hospitalization, the devitalized tissue was debrided. The RPL had an extensive devitalized area with exposed bone in the phalanges and necrosis in the pads. The left pelvic limb (LPL) suffered minor complications, with involvement of the phalangeal region. After 12 days, with HBOT every 48 h, exuberant granulation tissue was observed. After 17 days, the patient was discharged, and HBOT sessions were performed weekly. Gangrene of the midfoot and lack of proprioception were observed in RPL, while LPL showed bone divulsion of the 1st, 3rd, and 4th phalanges. Because of the poor prognosis for limb viability, the RPL was partially amputated, and a self-threaded intraosseous prosthesis was inserted. Discussion: The cardiorespiratory arrest that occurred during the surgical procedure to reduce the diaphragmatic hernia without thromboprophylaxis may have contributed to the peripheral ischemia. HBOT was proposed for the adjuvant treatment of ischemic injury because it is especially indicated for cases of ischemia-reperfusion injury. The main hematological parameters were evaluated at an average interval of 7 days. While the platelet count and hematocrit increased, the leukocytosis decreased. This demonstrates the benefit of oxygen therapy in the reported patient. The use of HBOT in orthopedic injuries is known to result mainly in stimulation of osteoblasts, promoting osseointegration of the prosthesis. We conclude that the adjuvant treatment with HBOT helped to preserve a large segment of both pelvic limbs, prevent the progression of necrosis, and provide a healthy bed for fixation of an osseointegrated prosthesis in the RPL, resulting in clinical improvement of the patient.

Fixed bilateral endo-exo prostheses in feline femur - case report / Endo-exoprótese bilateral fixa em fêmur de felino - relato de caso

The use of endo-exo prosthesis is an alternative to improve the quality of life of amputees, allowing correct distribution of body weight, reducing skin problems and pain related to the implant, and reducing lameness. The aim of this paper is to report the use of a fixed bilateral endo-exo femur prostheses in a cat with amputation prior to treatment. The endoprostheses were made with titanium and the exoprostheses were made with 3D printing technology. A longitudinal craniolateral surgical approach was used and the skin incision was made over the knee-joint, then fascia lata incision, followed by biceps femoris and vastus lateralis muscles retraction, incision through the joint capsule to expose the tibiofemoral joint, disarticulation, and tibia and fibula removal. Afterwards, a femoral leveling osteotomy and insertion of the implant in the medullary canal were performed, being attached in the cis and trans cortical bone. The patient was evaluated in the immediate post-operative and periodically thereafter, showing satisfactory results, without macroscopic signs of rejection, wound dehiscence or infection, fracture, or injury of limbs, and presented adapted walking. Furthermore, it was observed the return to common behaviors for the species.

O uso de endoexoprótese é uma alternativa para melhoria na qualidade de vida de pacientes amputados, permitindo distribuição correta do peso corporal, redução de problemas de pele e dor ligadas ao implante e redução da claudicação. Este trabalho objetivou relatar a utilização de endoexoprótese bilateral fixa em fêmur em felino com amputação prévia ao atendimento. Foram modeladas endopróteses em titânio e exopróteses projetadas e impressas em 3D. O acesso cirúrgico, em ambos os membros, foi realizado por incisão craniolateral transarticular da pele, incisão da fáscia lata, rebatimento dos músculos bíceps femoral e vasto lateral, incisão da cápsula articular para exposição da articulação femorotibial, desarticulação e remoção cirúrgica da tibia e da fibula. Em seguida, realizou-se osteotomia niveladora femoral e inserção do implante no canal medular, sendo esse fixo nas corticais cis e trans. O paciente foi avaliado no pós-cirúrgico imediato e posteriormente de forma periódica, demonstrando resultados satisfatórios, sem sinais macroscópicos de rejeição, deiscência ou infecção da ferida cirúrgica, fratura ou lesão de membros, e apresentava deambulação adaptada. Além disso, foi observado o retorno de comportamentos comuns da espécie.

Development of an intervertebral disc prosthesis prototype for the canine cervical spine / Desenvolvimento de um protótipo de prótese de disco intervertebral para a coluna vertebral cervical de cães

Cervical arthroplasty with disc prosthesis has been proposed as a treatment option for dogs with Cervical Spondylomyelopathy. The present study developed a novel vertebral disc prosthesis for dogs. Sixteen Functional Spinal Units (C5-C6) were collected from dog cadavers with body weights ranging between 25 and 35 kg, and their vertebral measurements were used to design a prosthetic disc. The sizing of the prosthesis was performed based on the averages of the measurements of width, height, and length of the vertebral bodies from C5-C6 of all specimens. The prosthesis was developed using the Rhinoceros 3D® and SolidWorks® programs, and 3D prototyping was carried out to define the best design. The developed prosthesis consisted of two independent parts that are fixed to the cranial and caudal vertebral bodies, in the intervertebral space, and fitted together by metal-to-metal surfaces capable of moving in the lateral, ventral, and dorsal directions. Each part of the prosthesis is angled in two portions: vertically, in the intervertebral space, and horizontally, in contact with the ventral surface of the vertebral bodies, both of which are fixed by means of monocortical locking screws. The design of the developed prototype allowed a good fit in the intervertebral space between C4-C5, C5-C6, and C6-C7.

A artroplastia cervical com prótese de disco tem sido proposta como uma opção de tratamento para cães com Espondilomielopatia Cervical. O presente estudo teve como objetivo desenvolver uma nova prótese de disco intervertebral para cães. Dezesseis Unidades Funcionais de Coluna Vertebral (C5-C6) foram coletadas de cadáveres de cães com peso corporal variando entre 25 e 35 kg, e suas medidas vertebrais foram usadas para projetar um disco intervertebral protético. O dimensionamento da prótese foi realizado com base nas médias das mensurações da largura, altura e comprimento dos corpos vertebrais de C5-C6 de todos os espécimes. A prótese foi desenvolvida nos programas Rhinoceros 3D® e SolidWorks® e utilizou-se prototipagem em 3D para a definição do melhor design. A prótese desenvolvida é formada por duas partes independentes que se fixam às espífises dos corpos vertebrais cranial e caudalmente ao espaço intervertebral, e se encaixam entre si por superfícies de metal-metal com capacidade de movimentação nas direções lateral, ventral e dorsal. Cada parte da prótese é angulada em duas porções: a vertical, que fica no espaço intervertebral, e a horizontal, que fica em contato com a superfície ventral dos corpos vertebrais, ambas as quais são fixadas por meio de parafusos bloqueados monocorticais. O design do protótipo desenvolvido permitiu bom encaixe no espaço intervertebral entre C4-C5, C5-C6 e C6-C7.

Finite element analysis of a new intervertebral disc prosthesis developed for the canine cervical spine / Elementos finitos de uma nova prótese de disco intervertebral desenvolvida para a coluna cervical canina

Cervical spondylomyelopathy (CSM) is a disease that affects mostly large- and giant-breed dogs. It is characterized by abnormalities of the cervical spine that may cause damage to the spinal cord and nerve roots. Cervical disc arthroplasty has been proposed as a treatment option in veterinary medicine. The current study evaluated the main stresses in a novel canine vertebral disc prosthesis and vertebral bodies using finite element analysis. Two experimental groups were created based on the material used for the prosthesis: stainless steel group (SSG) and titanium alloy group (TAG). Vertebral and prosthetic average equivalents von-Mises stress (VMS) and minimum principal stress (MiPS) were assessed while compressive, tensile, and lateral bending shear loads were applied. The stainless steel group had greater VMS distribution on all the evaluated parameters while the titanium alloy group had greater MiPS. Stresses were more concentrated on the lateral and ventral surfaces of the vertebral bodies than on their endplates. The average prosthetic stresses were more concentrated on the bone/implant contact surface than on the prosthesis/screw interface. Maximum stresses were concentrated in the screws' cranial surface. The novel prosthesis allows even distribution along the vertebral body. Comparing prosthesis materials, titanium alloy was marginally superior regarding average stresses in all directions and should be less likely to suffer subsidence.

Espondilomielopatia cervical (EMC) é uma doença que geralmente afeta cães de raças grandes e gigantes. Ela é caracterizada por anormalidades da coluna cervical que podem causar danos à medula espinhal ou às raízes nervosas. Artroplastia cervical com prótese de disco tem sido proposta como opção de tratamento na medicina veterinária. O presente estudo teve como objetivo avaliar os principais estresses em uma nova prótese de disco intervertebral canina e corpos vertebrais por meio da análise de elementos finitos. Foram compostos dois grupos experimentais que representaram o material constituinte da nova prótese: grupos aço inoxidável (SSG) e o liga de titânio (TAG). Tensões equivalente de von-Mises (VMS) e tensão principal mínima (MiPS) média foram avaliadas sob forças de compressão, tração e torção para vértebras e prótese. O grupo SSG teve maior distribuição de VMS para todos parâmetros avaliados, enquanto o grupo TAG teve maior MiPS. Estresses estiveram mais concentrados nas superfícies lateral e ventral dos corpos vertebrais do que nas placas terminais. Os estresses médios da prótese foram mais concentrados na superfície de contato osso/implante do que na interface prótese/parafuso. Estresses máximos foram concentrados na superfície cranial do parafuso. A nova prótese permitiu distribuição uniforme do estresse ao longo do corpo vertebral. Comparando os materiais da prótese, a liga de titânio foi marginalmente superior quanto aos estresses médios em todas as direções, sendo menos provável que sofra afundamento da prótese.

Surgical approach in correction of a crack in the gnathotheca of a black swan (Cygnus atratus, Latham, 1790): first case report / Abordagem cirúrgica em correção de fissura na gnatoteca em um cisne-negro (Cygnus atratus, Latham, 1790): primeiro relato de caso

The black swan (Cygnus atratus, LATHAM, 1790) is a bird kept as an ornamental in zoos. Because of their long beaks they tend to have a reserved prognosis in musculoskeletal disorders such as beak trauma, secondary to skull bone fractures, presenting irreversible lesions. The aim of this report is present a clinical surgical innovation in the repair of a black swan's gnathotheca fissure with the application of non-conventional materials used. It was observed that one of the swans kept in a zoo display area had difficulty feeding, with associated weight loss. It was observed tissue loss and a lacerative lesion in the caudal sublingual region of its beak. The lesion was corrected by a separate simple suture in the cranial region of the beak and with a x-clamping using steel surgical wire and the application of dental resin in the distal region to perform a sustentation bridge in the beak end-gap. After 12 days, the animal was able to feed again and remained perfectly adapted to the restoration, reestablishing the anatomical and physiological function of its beak.

O cisne-negro (Cygnus atratus, Latham, 1790) é uma ave mantida como ornamental em zoológicos. Por apresentar bicos longos, tende a ter prognóstico reservado em afecções musculoesqueléticas, como traumas de bico secundários e fraturas de ossos do crânio, com lesões irreversíveis. O objetivo deste relato é apresentar uma inovação clínica cirúrgica no reparo de fissura na gnatoteca de um cisne-negro, com a utilização de materiais não convencionais. Observou-se que um dos cisnes mantidos em uma área de exibição de um zoológico apresentava dificuldade para se alimentar, com perda de peso associada. Constatou-se perda tecidual e lesão lacerativa na região sublingual caudal de seu bico. A lesão foi corrigida por meio de sutura simples separada na região cranial do bico e posterior sutura em x com fio cirúrgico de aço, finalizando com aplicação de resina odontológica na região distal para realização de ponte de sustentação do bico. Após 12 dias, o animal conseguiu se alimentar novamente e se manteve perfeitamente adaptado à restauração, restabelecendo a função anatômica e fisiológica de seu bico.

Carpal valgus angle deviation in Thoroughbred foals corrected using single transphyseal screw implant / Correção de desvio angular valgo do carpo em potros Puro-sangue com implante de parafuso transfiseal único

The objective of this study was to demonstrate the effectiveness of the single transphyseal screw technique in foals diagnosed with carpal valgus deviation. This study included 22 thoroughbred animals of both sexes, with a mean age of 30 days. All animals had a carpal valgus deviation >5° with irregular development of the distal epiphysis of the radius. All animals were surgically treated to correct the carpal valgus deviation by creating a bridge using a single transphyseal screw. Surgical intervention was performed for 40 limbs, comprising 19 right and 21 left thoracic limbs. This corresponded to four animals with carpal valgus deviation >5° in only one of the limbs and 18 with the deviation in both limbs. It was observed that 38/40 treated limbs (95%) achieved normal angulation according to the literature, i.e., angulation between 0° and 5°. No statistical differences were observed between the affected limbs. The single transphyseal screw technique can be used for the correction of carpal valgus deviation in foals. It is indicated in animals with an average age of 30 days (20-55 days), as its main advantages are rapid application, simple execution, and limited trans- and post-surgical complications, making it an effective procedure in thoroughbred foals with carpal valgus angular deviation.

O objetivo do presente estudo foi demonstrar a viabilidade da aplicação da técnica de parafuso único transfiseal em potros, com diagnóstico de desvio valgo do carpo. Foram selecionados 22 animais, da raça PSI, com idade média de 30 dias, de ambos os sexos. Todos os animais apresentavam desvio valgo do carpo acima de cinco graus, com desenvolvimento irregular da epífise distal do rádio. Os animais foram submetidos à cirurgia corretiva para o desvio valgo do carpo por meio da realização de ponte com um único parafuso transfiseal. Foram submetidos à intervenção cirúrgica 40 membros, divididos entre membros torácicos direito e esquerdo 19 e 21, respectivamente, que corresponderam a quatro animais com desvio acima de 5 graus valgo do carpo em apenas um dos membros e 18 animais com o procedimento nos dois membros. Observou-se que 38 dos 40 membros tratados, ou seja, 95%, retornaram a uma angulação considerada normal, entre zero e cinco graus Dois animais apresentaram infecção do implante, de maneira que eles reduziram a angulação, porém não o suficiente para enquadrá-los na angulação normal estabelecida pela literatura. Não houve diferença estatística entre os membros acometidos. A técnica de aplicação do único parafuso transfiseal pode ser indicada para correção do desvio valgo do carpo em potros. Deve ser indicada em animais com idade média de 30 dias (20 a 55 dias de vida), por ter como principais vantagens aplicação rápida, execução simples e com limitadas intercorrências trans e pós-cirúrgicas.

Fraturas apendiculares em cães e gatos: métodos de tratamento e desfechos / Appendicular fractures in dogs and cats: treatment methods and outcome

O objetivo deste estudo retrospectivo foi identificar a ocorrência de fraturas apendiculares em cães e gatos, os métodos de tratamento e os resultados obtidos com os mesmos, no Hospital Veterinário (HV) da Universidade Regional do Noroeste do Estado do Rio Grande do Sul (Unijuí), no município de Ijuí - RS, no período de abril de 2013 a abril de 2022. De um total de 370 procedimentos cirúrgicos para tratamento de fraturas do esqueleto apendicular, 117 foram em fêmur (31,6%), 77 em tíbia e fíbula (20,8%), 62 em rádio e ulna (16,8%), 49 em úmero (13,2%), 45 em pelve (12,2%), 7 em metatarso e metacarpo (1,9%), 7 em tarso e carpo (1,9%), 4 em escápula (1,1%) e 2 em falanges (0,5%). O número de procedimentos foi superior ao número de animais, pois alguns apresentavam mais de uma fratura em diferentes ossos. Entre os 329 animais reportados neste estudo, concluiu-se que a principal causa de fraturas em cães e gatos foi atropelamento, sendo os filhotes os mais acometidos e as fraturas femorais as mais frequentes. Os fixadores esqueléticos externos destacaram-se como o método mais utilizado e o desfecho das osteossínteses foi satisfatório, sendo que a maior casuística correspondeu a fraturas cicatrizadas.

This retrospective study aimed to identify the occurrence of appendicular fractures in dogs and cats, treatment methods, and results obtained with them, at the Veterinary Hospital (VH) of the Regional University of the Northwest of the State of Rio Grande do Sul (Unijuí), in the city of Ijuí/RS, from April 2013 to April 2022. A total of 370 surgical procedures for the treatment of fractures of the appendicular skeleton was performed: 117 were in the fêmur (31,6%), 77 in the tíbia and fíbula (20,8%), 62 in the radius and ulna (16,8%), 49 in the humerus (13,2%), 45 in pélvis (12,2%), 7 in metatarsus and metacarpus (1,9%), 7 in tarsus and carpus (1,9%), 4 in the scapula (1,1%), and 2 in phalanges (0,5%). The number of procedures was higher than the number of animals, as some had more than one fracture in different bones. Among the 329 animals reported in this study, it was concluded that the main cause of fractures in dogs and cats was being run over, puppies were the most affected, and femoral fractures were the most frequent. External skeletal fixators stood out as the most used method and the outcome of osteosynthesis was satisfactory, with the largest number of cases corresponding to healed fractures.

USE OF PROSTHESIS IN A CAPARACE FRACTURE OF Chelonoidis carbonarius (Testudines: Testudinidae): CASE REPORT / USE OF PROSTHESIS IN A CAPARACE FRACTURE OF Chelonoidis carbonarius (Testudines: Testudinidae)

The testudines are members of the Reptilia class, they are ectothermic and differ from other reptiles by the presence of the shell, which covers most of their bodies. Shell fractures are common in these animals and can occur due to several factors, mainly trauma. This paper aims to report the use of a prosthesis in a red-footed tortoise (Chelonoidis carbonarius). An adult female weighing 2.45 kg was sent to the Setor de Animais Silvestres of Veterinary Hospital of Universidade de Brasília. The specimen presented a carapace fracture caused by compress of garbage truck. Even after the healing of the lesion, there was persistence communication between the celomatic cavity and the environment, which caused recurrent pneumonia. After stabilization of the patient and treatment of infections, an adhesive cover was placed to isolate the cellomic cavity, which was changed periodically. Moreover, it was decided to make a prosthesis with acrylic resin, since it was not feasible to perform the repair by conventional methods. The method was satisfactory in the sealing of the carapace and the animal was monitored for a month without showing signs of pneumonia or any other complications.

Testudines are members ofthe Reptilia class, they are ectothermic anddiffer from other reptiles by the presence ofthe shell, which covers most of their bodies.Shell fractures are common in these animalsand can occur due to several factors, mainlytrauma. This paper aims to report the useof prosthesis in a red-footed tortoise (Chelonoidis carbonarius). An adult female weighing 2.45 kg was sent to the Wild AnimalSector of Veterinary Hospital of Universityof Brasilia. The specimen presented carapace fracture caused by compress of garbage truck. Even after healing the lesion, there was persistent communication betweenthe coelomic cavity and the environment,which caused recurrent pneumonia. Afterstabilization of the patient and treatmentof infections, an adhesive cover was placedto isolate the coelomic cavity, which waschanged periodically. Moreover, it was decided to make a prosthesis with acrylic resin, since it was not feasible to perform the repair by conventional methods. The methodwas satisfactory in the sealing of the carapace and the animal was monitored for amonth without showing signs of pneumoniaor any other complications.

Prótese intraescleral em um cão - evisceração e implantação / Intrascleral prosthesis in a dog - evisceration and implantation

Background: There is no hope of preserving vision at the terminal stage of glaucoma, and surgical treatment is indicated in thesecases. Among the various surgical techniques used, eye evisceration with implantation of an intrascleral prosthesis provide thebest cosmetic results. Even though eye evisceration with prosthesis implantation represents an excellent treatment option forterminal glaucoma, reports on the use of this technique in dogs are scarce in the current literature. The aim of this work is to reporta case of a dog with end-stage glaucoma subjected to eye evisceration surgery and implantation of an intrascleral prosthesis.Case: A 7-year-old bitch mixed breed with a history of glaucoma secondary to uveitis with no response to medical therapy wasreferred to the Ophthalmology service of the University Veterinary Hospital of Coimbra (HVUC), Portugal At the ophthalmicexamination, the glaucomatous left eye was buphthalmic, with congested episcleral blood vessels, mydriasis, and posterior luxation of the lens; there was no response to threat or obfuscation, no direct and consensual pupillary reflex, nor pupillary reflexesto chromatic light. The intraocular pressure (IOP) was 55 mmHg, and the Schirmer’s tear test (STT-1) result was 19 mm/min.Ophthalmoscopy revealed attenuated retinal blood vessels and a pale optic papilla with mild excavation. The right eye wasfunctional, with all parameters assessed on examination and by tests within the normal ranges for the species. An ultrasoundexamination of the left eye confirmed the presence of posterior luxation of the lens and buphthalmia in the absence of intraocularneoplasm. In view of the patient’s history and results of the clinical examinations, a surgical approach was indicated to treat theglaucomatous eye. The patient’s tutor requested a surgical procedure that...

Prótese intraescleral em um cão - evisceração e implantação / Intrascleral prosthesis in a dog - evisceration and implantation

Background: There is no hope of preserving vision at the terminal stage of glaucoma, and surgical treatment is indicated in thesecases. Among the various surgical techniques used, eye evisceration with implantation of an intrascleral prosthesis provide thebest cosmetic results. Even though eye evisceration with prosthesis implantation represents an excellent treatment option forterminal glaucoma, reports on the use of this technique in dogs are scarce in the current literature. The aim of this work is to reporta case of a dog with end-stage glaucoma subjected to eye evisceration surgery and implantation of an intrascleral prosthesis.Case: A 7-year-old bitch mixed breed with a history of glaucoma secondary to uveitis with no response to medical therapy wasreferred to the Ophthalmology service of the University Veterinary Hospital of Coimbra (HVUC), Portugal At the ophthalmicexamination, the glaucomatous left eye was buphthalmic, with congested episcleral blood vessels, mydriasis, and posterior luxation of the lens; there was no response to threat or obfuscation, no direct and consensual pupillary reflex, nor pupillary reflexesto chromatic light. The intraocular pressure (IOP) was 55 mmHg, and the Schirmers tear test (STT-1) result was 19 mm/min.Ophthalmoscopy revealed attenuated retinal blood vessels and a pale optic papilla with mild excavation. The right eye wasfunctional, with all parameters assessed on examination and by tests within the normal ranges for the species. An ultrasoundexamination of the left eye confirmed the presence of posterior luxation of the lens and buphthalmia in the absence of intraocularneoplasm. In view of the patients history and results of the clinical examinations, a surgical approach was indicated to treat theglaucomatous eye. The patients tutor requested a surgical procedure that...(AU)

TGF-ß1 and CD68 immunoexpression in capsules formed by textured implants with and without mesh coverage: a study on female rats

Purpose: To evaluate fibrosis formation and number of macrophages in capsules formed around textured implants without and with mesh coverage. Methods: Fibrosis was analyzed through transforming growth factor-beta 1 (TGF-ß1) immunomarker expression and the number of macrophages through CD68 percentage of cells in magnified field. Sixty female Wistar rats were distributed into two groups of 30 rats (unmeshed and meshed). Each group was then subdivided into two subgroups for postoperative evaluation after 30 and 90 days. The p value was adjusted by Bonferroni lower than 0.012. Results: No difference was observed in fibrosis between meshed and unmeshed groups (30 days p = 0.436; 90 days p = 0.079) and from 30 to 90 days in the unmeshed group (p = 0.426). The meshed group showed higher fibrosis on the 90th day (p = 0.001). The number of macrophages was similar between groups without and with mesh coverage (30 days p = 0.218; 90 days p = 0.044), and similar between subgroups 30 and 90 days (unmeshed p = 0.085; meshed p = 0.059). Conclusions: In the meshed group, fibrosis formation was higher at 90 days and the mesh-covered implants produced capsules similar to microtextured ones when analyzing macrophages. Due to these characteristics, mesh coating did not seem to significantly affect the local fibrosis formation.

Estabilização de ombro em um gato ­ Relato de caso / Shoulder estabilization in a cat ­ Case report

A estabilidade da articulação do ombro é garantida por ligamentos, cápsula articular, tendões e músculos, contudo traumas podem causar falência dos mecanismos estabilizadores, com consequente luxação ou instabilidade articular. Objetivou-se relatar o caso de instabilidade medial e lateral de ombro direito em felino sem raça definida, atendido com queixa de claudicação aguda de membro torácico secundária a trauma por confronto com outro animal. Inicialmente foi realizado tratamento clínico por meio de imobilização articular. Contudo, devido ao insucesso da técnica, procedeu-se para o tratamento cirúrgico de estabilização articular com prótese ligamentar sintética. No pós-operatório imediato, evidenciou-se ausência de crepitações e instabilidade articular. Após oito dias da cirurgia, o paciente apresentou retorno total às funções de apoio do membro e sem sinais de dor ou redução de movimentos. Concluiu-se que, embora de reduzida ocorrência, a instabilidade de origem traumática do ombro configura-se como um diferencial para claudicação aguda de membro torácico e que o tratamento cirúrgico pode ser necessário, mostrando-se eficiente na resolução de tais casos com o acesso e técnica de estabilização propostos.

The stability of the shoulder joint is granted by ligaments, joint capsule, tendons and muscles. However, traumatic injuries can cause failure of the stabilization mechanisms, which leads to articular luxation or instability. The aim of the paper is to report a case of medial and lateral right shoulder joint instability in a mixed-breed cat, presenting acute forelimb lameness after a fight trauma with another cat. Initially, it was recommended a conservative treatment through articular immobilization. However, the technique was unsuccessful, and the surgery treatment was performed, to stabilize the joint with synthetic ligament prosthetic. In the postoperative period, no crepitation or instability were identified. After eight days of surgery, the patient returned totally to the normal function of the forelimb, without movement restriction or pain. It was concluded that, although rare, the traumatic shoulder joint instability is a differential diagnosis for acute forelimb lameness and the surgical treatment can be necessary, showing a good result in the resolution of these injuries with the surgical approach and stabilization method proposed.

Use of prosthesis in a caparace fracture of Chelonoidis carbonarius (Testudines: Testudinidae) / Emprego de prótese em fratura de carapaça de Chelonoidis carbonarius (Testudines: Testudinidae)

Testudines are members of the Reptilia class, they are ectothermic and differ from other reptiles by the presence of the shell, which covers most of their bodies. Shell fractures are common in these animals and can occur due to several factors, mainly trauma. This paper aims to report the use of prosthesis in a red-footed tortoise (Chelonoidis carbonarius). An adult female weighing 2.45 kg was sent to the Wild Animal Sector of Veterinary Hospital of University of Brasilia. The specimen presented carapace fracture caused by compress of garbage truck. Even after healing the lesion, there was persistent communication between the coelomic cavity and the environment, which caused recurrent pneumonia. After stabilization of the patient and treatment of infections, an adhesive cover was placed to isolate the coelomic cavity, which was changed periodically. Moreover, it was decided to make a prosthesis with acrylic resin, since it was not feasible to perform the repair by conventional methods. The method was satisfactory in the sealing of the carapace and the animal was monitored for a month without showing signs of pneumonia or any other complications.(AU)

Os testudines pertencem à classe Reptilia, são ectotérmicos e se diferem dos demais répteis pela presença do casco, que envolve a maior parte de seus corpos. Fraturas nesse arcabouço ósseo são comuns e podem ocorrer devido a diversos fatores, principalmente traumas. O presente trabalho tem como objetivo relatar um caso de colocação de prótese em casco de jabuti-piranga (Chelonoidis carbonarius). Um exemplar adulto, fêmea, de 2,45 kg, foi encaminhado ao Setor de Animais Silvestres do Hospital Veterinário da Universidade de Brasília. O espécime apresentava fratura de carapaça provocada por prensas compactadoras de um caminhão de coleta de lixo domiciliar. Mesmo após a cicatrização da lesão, houve persistência de uma comunicação da cavidade celomática com o meio externo, o que ocasionava quadros de pneumonia recorrentes. Após estabilização do paciente e tratamento das infecções, foi colocada uma cobertura com esparadrapo para isolar a cavidade celomática, que era trocada periodicamente. Posteriormente, decidiu-se pela confecção de uma prótese feita de resina acrílica, visto que não era viável realizar o reparo por técnicas convencionais. O método se mostrou satisfatório na vedação da carapaça e o animal foi acompanhado durante um mês sem demonstrar indícios de pneumonia ou qualquer complicação.(AU)

Reconstrução de palato com malha de polipropileno e prótese acrílica para correção de fístula oronasal adquirida em cão / Palate reconstruction with polypropylene mesh and acrylic prosthesis in dog for correcton of acquired oronosal fistulae

As fístulas oronosais adquiridas são defeitos que permitem a comunicação anormal entre as cavidades oral e nasal. Inúmeras causas podem ser atribuídas à etiologia de tal defeito. O presente trabalho visa relatar o caso de um cão com fístula oronasal adquirida que foi submetido à reconstrução cirúrgica do palato com o uso de malha de polipropileno e prótese acrílica. Após estabilização do quadro clínico e remoção manual das larvas, o paciente foi encaminhado para o desbridamento cirúrgico das lesões orais e correção do defeito no palato. A palatoplastia foi realizada com o uso da malha e resina de polimetilmetacrilato autopolimerizável. A malha foi suturada sobre o defeito palatino com pontos simples separados e fio náilon 3-0 nas extremidades da ferida. Em seguida, a resina foi preparada e, ao atingir consistência adequada, foi aplicada e modelada sobre o a malha de polipropileno com o auxílio de um descolador de Molt, sendo também suturada nas bordas da fístula com pontos simples separados e fio náilon 3-0. No mesmo tempo cirúrgico foi inserida uma sonda esofágica para alimentação enteral. Devido complicações cirúrgicas no pós operatório, o paciente foi submetido a mais duas intervenções cirúrgicas para desfecho satisfatório do tratamento. Conclui-se que associação entre a tela de polipropileno e a prótese acrílica foi uma alternativa exequível para a palatoplastia em cão.

Acquired oronosal fistulae are abnormal communication between the oral and nasal cavities. A oronasal fistula can be the result of different causes, like oral myiasis. The objetctive of these paper is to report the case of a dog with acquired oronasal fistula that underwent surgical reconstruction of the palate using polypropylene mesh and acrylic prosthesis. After stabilization of the patient ́s clinical condition and mecanic removal of the larvae, the dog was referred for surgical debridement of the oral lesions and correction of the defect in the palate. Palatoplasty was performed using a mesh and polymethylmethacrylate resin. The mesh was sutured over the palatal defect with separate simple suture and 3-0 naylon thread at the ends of the wound. Then, the resin was prepared and, upon reaching adequate consistency, it was applied and shaped over the polypropylene mesh with Molt peeler. It was also sutured on the edges of the fistula with separate simple suture and 3-0 nylon suture. At the same surgical time, an esophageal tube was inserted for enteral feeding. Due to complications, the dog underwent two more surgical interventions for a satisfactory treatment outcome. It is concluded that the association between the polypropylene mesh and the acrylic prosthesis was a practical alternative for palatoplasty in dogs after oral myiasis.

Extraluminal nitinol prosthesis in the treatment of intrathoracic tracheal collapse in a dog / Uso de prótese extraluminal de nitinol no tratamento de colapso traqueal intratorácico em um cão

A six-month-old male Brazilian Terrier with persistent cough and dyspnea was diagnosed with intrathoracic tracheal collapse and pneumonia after chest radiographics. The medical treatment was performed, and an extraluminal nitinol prosthesis was placed through thoracic access. The dog did not presented recurrence of dyspnea or pneumonia for four years after the surgical procedure. Placement of the extraluminal prosthesis with the thoracic approach effectively stabilized intrathoracic tracheal collapse without causing any structural damage in the thoracic region. Therefore, this is the first report of a successful use of this prosthesis with an intercostal approach in dogs for intrathoracic trachea collapse.

Um cão macho, da raça Terrier Brasileiro de seis meses de idade, com dispnéia e tosse persistente foi diagnosticado com colapso traqueal intratorácico e pneumonia após estudo radiográfico de tórax. Foi instituído tratamento médico e realizada toracotomia para a implantação de prótese traqueal extraluminal de nitinol. O animal não manifestou dispneia ou pneumonia durante os quatro anos posteriores ao procedimento. A implantação da prótese extraluminal através da toracotomia foi eficaz para o tratamento do colapso traqueal intratorácico, sem provocar danos estruturais na região torácica. Desta forma, este é primeiro relato da utilização bem-sucedida deste tipo de prótese, a partir da abordagem intercostal, no tratamento de cães com colapso traqueal intratorácico.

Femoral orthopedic implants in dogs with titanium - mechanical evaluation

Background: Orthopedic implants are commonly used for different types of surgical procedures to gain optimal functionand to provide stability to both bones and tendon structures. When inserting these implants, the characteristics of the material are important for surgical success, and the ideal implant must be biocompatible and nonallergenic. However, whenmolding an implant to the bone structure, its resistance can change significantly. Implants can be temporary or permanentin the body, and metal possesses properties that make it acceptable for bone repair. In biomedical implants, 2 types aremost common, commercially pure (CP)-Ti and Ti-6A1-4V. They both provide stable fixation and low risk of loosening.Implants made with the same material and composition can perform differently if the material has been altered by processing techniques for different scenarios. Stress, strain and elastic modulus are the primary metrics used in the description ofimplant materials. They can be calculated based on mechanical tests of specimens with defined geometry, most commonlytensile, bending and torsional tests. In order to better evaluate those changes, we compared the mechanical characteristicsof titanium bone plates, before and after they were molded to the bone, to verify and quantify the loss of stiffness andresistance after molding the plate.Materials, Methods & Results: The study was prospective. Orthopedic implant made of commercially pure titanium (CPTi) were divided into 2 groups, one group without plate molding and the other with plate molding to a dog femora bone.Thirty-six plates of different sizes (5.0, 6.5, 8.0, 9.0, 10.0- and 11.0-mm diameter) were divided into 6 groups containing6 plates of each size and submitted to the 4-point flexion test of resistance, using a piece of dog femur (weights of 5, 10,15, 20 and 25 kg) as the bone in which the...

Femoral orthopedic implants in dogs with titanium - mechanical evaluation

Background: Orthopedic implants are commonly used for different types of surgical procedures to gain optimal functionand to provide stability to both bones and tendon structures. When inserting these implants, the characteristics of the material are important for surgical success, and the ideal implant must be biocompatible and nonallergenic. However, whenmolding an implant to the bone structure, its resistance can change significantly. Implants can be temporary or permanentin the body, and metal possesses properties that make it acceptable for bone repair. In biomedical implants, 2 types aremost common, commercially pure (CP)-Ti and Ti-6A1-4V. They both provide stable fixation and low risk of loosening.Implants made with the same material and composition can perform differently if the material has been altered by processing techniques for different scenarios. Stress, strain and elastic modulus are the primary metrics used in the description ofimplant materials. They can be calculated based on mechanical tests of specimens with defined geometry, most commonlytensile, bending and torsional tests. In order to better evaluate those changes, we compared the mechanical characteristicsof titanium bone plates, before and after they were molded to the bone, to verify and quantify the loss of stiffness andresistance after molding the plate.Materials, Methods & Results: The study was prospective. Orthopedic implant made of commercially pure titanium (CPTi) were divided into 2 groups, one group without plate molding and the other with plate molding to a dog femora bone.Thirty-six plates of different sizes (5.0, 6.5, 8.0, 9.0, 10.0- and 11.0-mm diameter) were divided into 6 groups containing6 plates of each size and submitted to the 4-point flexion test of resistance, using a piece of dog femur (weights of 5, 10,15, 20 and 25 kg) as the bone in which the...(AU)

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)

Biomechanical evaluation of a new femoral stem design for total hip replacement in a canine model

ABSTRACT Purpose To evaluate the biomechanical properties of a novel total hip replacement femoral stem. Methods Eight pairs of femurs from dog cadavers were used. The femurs were separated into different groups. A novel femoral stem with a convex proximal portion (Stem B) was biomechanically evaluated and compared to awell-known veterinary collared stem (Stem A). Femoral stems were inserted into the contralateral femurs from the same dog, forming 16 constructs. A flexo-compression load was applied on the axial axis of each sample. Maximum strength, deflection, stiffness, and energy absorption were analysed. Results Group B constructs showed significantly higher values (p ? 0.05) for the variables, except stiffness. The mean maximum strength was 1,347 ± 357 N for Group A and 1,805 ± 123 N for Group B (p ? 0.0069). The mean deflection was5.54 ± 2.63 mm for Group A and 10.03 ± 3.99 mm for Group B (p ? 0.0056). For the energy variable, the force was 6,203 ± 3,488 N/mm for Group A and 12,885 ± 5,056 N/mm for Group B (p ? 0.0054). Stem B had greater maximum strength, deflection, and energy. Conclusions The new stem was effective in neutralizing the impact of axial flexion-compression stresses during biomechanical tests in cadaveric models.