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.

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.

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.

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.

Infecções no sítio cirúrgico em cirurgias ortopédicas de equinos com a utilização de implantes: estudo retrospectivo (2009-2021) / Surgical site infections in equine orthopedic surgeries using implants: retrospective study (2009-2021

A infecção no sítio cirúrgico (ISC) é uma complicação grave que pode acontecer em decorrência das cirurgias ortopédicas que demandam a utilização de implantes nos equinos. Morbidade, tratamentos prolongados e, consequentemente, dispendiosos e até mesmo óbito, são decorrências desta complicação. O presente trabalho analisou de forma retrospectiva os equinos submetidos a osteossíntese ou artrodese, que apresentaram ISC no período pós-cirúrgico atendidos no Hospital Veterinário da FMVZ-USP no período de 2009 a 2021. Sessenta e sete equinos atenderam aos critérios de seleção e, destes, 13 (19,4%) apresentaram ISC no período pós-cirúrgico. Escherichia coli, Streptococcus sp. e Enterobacter cloacae complex foram os agentes mais comumente isolados e a remoção dos implantes foi realizada em 76,9% (10/13) dos pacientes. Aminoglicosídeos associados ou não aos beta-lactâmicos foram as classes de antimicrobianos utilizados na terapia prévia em 84,6% (11/13), houve alteração das drogas utilizadas depois do resultado da cultura e antibiograma em todos os casos, devido à resistência antimicrobiana identificada. A incidência de ISC foi similar ao relatado em outros trabalhos, a retirada dos implantes foi uma estratégia eficiente quando o tratamento clínico não surte melhora. A identificação dos agentes envolvidos e o antibiograma se mostraram decisivos para o manejo dos casos.(AU)

Surgical site infection (SSI) is a serious complication that can occur in orthopedic surgeries that require the use of implants in horses. Morbidity, prolonged and consequently expensive treatments, and even death are consequences of this complication. This paper retrospectively analyzed horses undergoing osteosynthesis or arthrodesis, which presented SSI in the post-surgical period, treated at the Veterinary Teaching Hospital of FMVZ-USP from 2009 to 2021. Sixty-seven horses met the selection criteria and of these, 13 (19.4%) had SSI in the postoperative period. Escherichia coli, Streptococcus sp, and Enterobacter cloacae complex were the most commonly isolated agents and implant removal was performed in 76.9% (10/13) of patients. Aminoglycosides associated or not with beta-lactams were the classes of antimicrobials used in previous therapy in 84.6% (11/13), and in all cases there was a change in the drugs used after the result of the culture and antibiogram, due to antimicrobial resistance identified. The incidence of SSI was similar as reported in other studies, and implant removal was an efficient strategy when clinical treatment fails to improve. The identification of the agents involved and the antibiogram was decisive for cases management.(AU)

Surgical correction of metatarsal angular deviation in a Thoroughbred filly using wedge metatarsal ostectomy: a case report / Correção cirúrgica de desvio angular metatársico em uma potra Puro-Sangue utilizando ostectomia em cunha: um relato de caso

This study describes a corrective procedure for a metatarsal angular malformation using wedge ostectomy in a 41-day-old Thoroughbred filly. A 41.6 °angular malformation of the metatarsus was corrected with wedge ostectomy of the left hindlimb in association with a type II external fixator and methyl methacrylate resin. The animal was subjected to the surgical procedure under general anesthesia. The filly was placed in dorsal recumbency with the left hind limb free for manipulation. A bone saw was used for the wedge ostectomy, while the bars for external fixation were placed using a drill. A Kirschner pin and acrylic resin were then applied. Radiographic images obtained immediately after surgery confirmed a total malformation reduction of 32.6 (from 41.6° to 9°). With medication and a Robert Jones bandage, intensive postoperative care was instituted to ensure that the animal adapted properly to the linear external fixator without overloading the pins and connection bars. No postoperative complications were observed. On the day after surgery, the filly was standing and walking with no signs of pain. After 180 days, total osseous calcification was achieved, and the implants were removed during the second surgery. The filly demonstrated adequate locomotion, performed all the movements, and ran without any difficulty in the paddock. The remaining discrete angular deviations were partially corrected using hoof trimming.

O objetivo desse estudo é descrever o procedimento de correção da malformação de desvio angular metatársico, utilizando ostectomia em cunha, em uma potra puro-sangue de 41 dias de idade. Uma malformação metatársica angular de 41.6º foi corrigida com a técnica de ostectomia em cunha, em associação com fixador externo tipo II e resina de metilmetacrilato, no membro pélvico esquerdo. O animal foi submetido à cirurgia sob protocolo de anestesia geral. A potra foi posicionada em decúbito dorsal, com o membro pélvico esquerdo livre para manipulação. Para a realização da ostectomia em cunha, foi utilizada uma serra óssea. Para a instalação das barras do fixador externo, uma furadeira foi utilizada e, para fixá-los, pinos de Kirschner e resina acrílica foram aplicados. Logo após a cirurgia, imagens radiográficas foram obtidas para confirmar a redução total de 32,6º (de 41,6º para 9º) de angulação. Para garantir que o animal se adaptasse ao fixador externo linear e não sobrecarregasse os pinos e barras, foram instituídos cuidados pós-operatórios intensos, com medicações e bandagem de Robert Jones. Não houve complicações no pós-operatório. No dia seguinte à cirurgia, a potra estava em pé, caminhando e sem sinais de dor. Após 180 dias, alcançou total calcificação óssea e os implantes puderam ser removidos em um segundo tempo cirúrgico. A potra demonstrou locomoção adequada, realizando todos os movimentos normais e pôde correr pelo pasto sem dificuldades. Um discreto desvio angular remanescente foi parcialmente corrigido por casqueamento.

Osteossíntese em maxila de anta-sul-americana (Tapirus terrestris Linnaeus, 1758) mantida sob cuidados humanos / Jaw osteosynthesis in a captive lowland tapir (Tapirus terrestris Linnaeus, 1758) kept under human care / Osteosintesis en la mandíbula de danta brasileña (Tapirus terrestris Linnaeus, 1758) mantenida bajo cuidado humano

A anta-sul-americana (Tapirus terrestris) é um mamífero de grande porte que habita áreas florestadas com abundância de água. É uma espécie bem representada em zoológicos e centros de triagem e de fácil adaptação ao ambiente artificial. Os problemas veterinários mais comuns em antas são lesões dermatológicas, oculares. em sistema musculoesquelético e, em menor proporção, problemas dentários. Objetivou-se relatar um caso de osteossintese em maxila superior de uma anta do sexo masculino de sete anos de idade, mantida sob cuidados humanos em um zoológico, com fratura da porção rostral maxilar. A metodologia de escolha para o tratamento foi a fixação interdentaria com flo de aço para coaptação dos fragmentos da fratura, seguida de ferulização para estabilização dos focos fraturários. Modificou- se a dieta para não sobrecarregar a força mastigatória durante o processo de cicatrização óssea. Após 120 dias, o animal foi submetido a nova anestesia para avaliação radiográfica e remoção dos implantes da osteossintese, apresentando boa recuperação e sendo incorporado ao grupo.(AU)

The lowland tapir (Tapirus terrestris) is a large mammal that inhabits. forested areas with abundance of water. It is well represented species in zoos and rescue centers and is easily adapted to the artificial environment. The most common veterinary problems in tapirs appear in skin, eye, musculoskeletal system and, to a lesser occurrence, teeth. The objective of this report is to present a case of osteosynthesis in the upper jaw of a seven-year-old male tapir, kept under human care in a zoo, with fracture of the rostral maxillary portion. The methodology of choice for the treatment was interdental fixation with steel wire, for coaptation of the fracture fragments, followed by splinting to stabilize the fracture foci. The diet was modified, to avoid overloading the masticatory force during the bone healing process. After 120 days, the animal underwent a new anesthesia for radiographic evaluation and removal of the osteosynthesis implants, showing good recovery and being incorporated into the group.(AU)

La danta brasilenä (Tapirus terrestris) es un grande mamifero que habita en zonas boscosas con abundancia de agua. Es una especie bien representada en zoológicos y centros de rescates y se adapta fácilmente al ambiente artificial. Los problemas veterinarios más comunes en los tapires son lesiones en piel, ojos y el sistema musculoesquelético y, en menor ocurrencia, los problemas dentales. El objetivo fue reportar un caso de osteosintesis en la mandíbula superior de un tapir macho de siete años, con fractura de la porción maxilar rostral, mantenido bajo cuidado humano en un zoológico. La metodologia de elección para el tratamiento fue el uso de ligadura interdental con alambre de acero para coaptación de los fragmentos de fractura, seguida de ferulización para estabilizar el foco de fractura. Se modificó la dieta para no sobrecargar la fuerza masticatoria durante el proceso de cicatrización osea. Después de 120 dias, el animal fue sometido a una nueva anestesia para evaluación radiográfica y retiro de los implantes de osteosintesis, mostrando buena recuperación e incorporándose al grupo.(AU)

Evaluation of the degradation of two bioabsorbable interference screws: an in-vivo study in sheep

Purpose: To evaluate in-vivo degradation of two bioabsorbable interference screws. Methods: Twenty-two crossbred Santa Inês ewes were used. A poly-DL-lactide (PDLLA) screw (70%/30%) was inserted in the right pelvic limb, and a PDLLA screw (70%) + ß-tri-calcium phosphate (ß-TCP) (30%) in the left pelvic limb. Animals were euthanized at one, four, seven and a half and 18 months after surgery. Plain radiography, computed tomography (CT), microCT, and histological analysis were accomplished. Results: PDLLA screw was hypodense at all evaluation moments, but with progressive density increase along the central axis, whereas PDLLA/ß-TCP was initially hyperdense and progressively lost this characteristic. No adverse reactions were observed on histological evaluation. Conclusions: The inclusion of ß-TCP favors screw degradation since the PDLLA/ß-TCP screws evidenced a more intense degradation process than the PDLLA screws at the last evaluation. PDLLA screws showed higher bone production, evident around the screw thread, inside the lateral perforations, and in the central canal, whereas the PDLLA/ß-TCP screws presented less bone tissue at the implantation site.

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)

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)

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.

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.

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.

Biocompatibility in vivo of elastic cartilage treated in alkaline solutions / [Biocompatibilidade in vivo de cartilagem elástica tratada em soluções alcalinas]

This study verified the in vivo biocompatibility of bovine elastic cartilage decellularized with alkaline solution in relation to the non-decellularized cartilage implanted in rats. Fifty Wistar rats were divided into two groups, with the experimental group (EG) receiving subcutaneous implants of cartilage treated in alkaline solution and the control group (CG) receiving subcutaneous implants of untreated cartilage. In both groups, the implants were removed on days 3, 7, 14, 21 and 42 with the preparation of histological slides stained with Hematoxylin and Eosin for the quantification of inflammatory cells, fibroblasts, angiogenesis, and cartilage degradation. The results showed that EG presented a less intense inflammatory infiltrate and better organization of collagen fibers compared to CG. It was concluded that the alkaline treatment provided better biocompatibility for elastic cartilage when implanted subcutaneously in rats.

Este estudo verificou a biocompatibilidade in vivo de cartilagem elástica bovina descelularizada com solução alcalina em relação à cartilagem não descelularizada implantada em ratos. Cinquenta ratos Wistar foram divididos em dois grupos; o grupo experimental (GE) recebeu implantes subcutâneos de cartilagem tratada em solução alcalina, e o grupo controle (GC) recebeu implantes subcutâneos de cartilagem não tratada. Em ambos os grupos, os implantes foram retirados nos dias três, sete, 14, 21 e 42, com a preparação de lâminas histológicas coradas com hematoxilina e eosina para a quantificação de células inflamatórias, de fibroblastos, de angiogênese e para a degradação da cartilagem. Os resultados mostraram que o GE apresentou infiltrado inflamatório menos intenso e melhor organização das fibras de colágeno em relação ao GC. Concluiu-se que o tratamento alcalino proporcionou melhor biocompatibilidade para a cartilagem elástica quando implantado por via subcutânea em ratos.

Anatomy and surgical approach to the humerus, radius and ulna of common sloth (Bradypus variegatus) / Anatomia e acesso cirúrgico ao úmero, rádio e ulna de preguiça-comum (Bradypus variegatus)

The surgical clinic of wild animals has increased in routine veterinary, where fractures by traumas are of frequent occurrence. This study determined the surgical accesses for osteosynthesis of the diaphyses of the humerus, radius and ulna of common sloth (Bradypus variegatus). Seven cadavers of B. variegatus were used for determination of the muscles of the thoracic limb, as well as the most important vessels and nerves, and better bone area for fixation of internal implants. The structural conformation of the radius and ulna in Bradypus variegatus were like those described in the literature for domestic animals but the humerus presented differences in the distal extremity because it was flattened. The musculature of Bradypus variegatus showed similarities with domestic animals. Due the different conformation of the humerus the surgical access to this bone can be performed by lateral approach, from the incision of M. triceps brachii lateral head, for fixation of the implant on the lateral side of the bone. Surgical access to the radius shaft can be performed by craniolateral approach, by incising the muscular fascia and separation of the cranially M. common digital extensor, and lateral digital extensor caudally. In ulna, a caudal access to the bone can be performed followed by release of the insertion m. flexor carpoulnar for placement of the internal implant on the lateral bone face.

A clínica cirúrgica de animais silvestres tem se intensificado na rotina veterinária, onde fraturas por traumas são frequentes. O objetivo deste estudo foi a determinação de acessos cirúrgicos para osteossíntese das diáfises do úmero, rádio e ulna de preguiça-comum (Bradypus variegatus). Sete cadáveres de B. variegatus foram utilizados para determinação dos músculos do membro torácico, bem como dos vasos e nervos mais importantes, e melhor área óssea para fixação de implantes internos. A conformação estrutural do rádio e da ulna em B. variegatus eram similares às descritas na literatura para animais domésticos, o úmero apresentou diferenças na extremidade distal pois apresentou-se achatado. A musculatura de B. variegatus mostrou semelhanças com os animais domésticos. Devido à diferente conformação do úmero o acesso cirúrgico a este osso pode ser realizado por abordagem lateral, a partir da incisão do M. tríceps braquial cabeça lateral, para fixação do implante na face lateral do osso. O acesso cirúrgico à diáfise do rádio pode ser realizado por abordagem craniolateral, por incisão da fáscia muscular e separação cranialmente do M. extensor digital comum e extensor digital lateral caudalmente. Na ulna, pode-se realizar um acesso caudal ao osso seguido de liberação da inserção do M. flexor carpoulnar para colocação do implante interno na face lateral do osso.

Fratura exposta do fêmur em preguiça-real (Choloepus didactylus) - tratamento e reabilitação / Open fracture of the femur in a two-toed sloth (Choloepus didactylus) - treatment and rehabilitation

Background: The Choloepus didactylus is characterized by having 2 fingers on the forelimbs and 3 on the hind limbs, being found more frequently in northern South America, in countries such as Venezuela, Guyana, Ecuador, Peru, and Brazil. In Brazil, deforestation of the Amazon rainforest has threatened the survival of C. didactylus. In addition, these animals can be affected by several diseases, being those of the musculoskeletal system with limited reports. Thus, the present report aimed to describe the treatment and evolution of an open fracture of the femur in a free-living Choloepus didactylus, which after rehabilitation was released back to the wild. Case: A free-living female two-toed sloth (Choloepus didactylus), weighing 7.0 kg, was found in Manaus city and referred to the Wild Animal Treatment Center (CETAS - IBAMA-AM) located in Amazonas, Brazil, after initial treatment and osteosynthesis in a private clinic (CVMinasPet). According to history, the animal had suffered electrocution 30 days ago and, as a result, had an extensive wound that resulted in the exposure of the knee joint, distal fracture of the femur, and areas of necrosis in the right pelvic limb. After cleansing of the area and removal of necrotic tissues, the fracture was stabilized with the cross-pinning technique (2 Steinmann pins). Then, the stifle joint was stabilized with external skeletal fixation (Type 1b, unilateral biplanar). The external fixator and cross-pins were removed 2 months after the surgical procedure, being observed bone healing. Next, the animal underwent physical rehabilitation for 30 days. After the rehabilitation period, a microchip and a radio collar were applied, and the sloth was released back to the wild. Discussion: Electrocution has been one of the causes of wildlife rescue, with consequences varying depending on the degree of the burn. Generally, the burn is most severe at the entry and exit sites. Since suspensory quadrupedal locomotion requires that sloths have specialized hands and feet to connect with the supports, probably the animal of the current report touched the right pelvic limb on a high-tension pole. The cross-pinning technique combined with the external fixator was used because the animal had an exposed Salter-Harris type I fracture with soft tissue loss. The younger the animal presents physeal fractures, the greater is the chance of developing growth abnormalities due to growth plate closure caused by fracture type or immobilization method. Since the sloth was a free-living animal, the age was unknown. However, pelvic limb length discrepancy was not observed after removing the implants. Culture and antimicrobial susceptibility test were not done and may be considered a limitation of this report. However, the application of ceftriaxone was adequate to control the infection, since the animal did not show signs of infection or draining sinus tracts. Ceftriaxone is a third-generation antibiotic that can be used in chronic osteomyelitis. In addition, the animal in the present report showed good adaptation to captive conditions that contributed to the clinical management. The longevity of the sloth in captivity can reach more than 30 years, but the goal is always to return the animal to nature after the treatment. Surgical treatment of the fracture and physical therapy after implant removal allowed this action in the current report, confirmed by monitoring with the radio collar.

A castor oil plant (Ricinus communis)-derived implant improves the biomechanical properties of noncritical bone defects

Purpose The biomechanical properties of the polyurethanes implant material derived from castor oil plant (Ricinus communis) were evaluated in a noncritical bone defect model in rat tibia. Methods After three weeks of the implant application, the tibias were tested by means of the biomechanical three-point flexion test and resistance, rigidity, energy at maximum load and maximum energy were evaluated. Nonparametric statistical analysis was performed. Results It was found that the group that received the implant behaved the same as the intact control group and also showed a significant increase in maximum load compared to the spontaneous repair group. Conclusions Our results indicate that the tibias with the implant material in a noncritical bone defect recover normal biomechanical parameters in less time than spontaneously.(AU)