Supracondylar femoral fractures in adult animals

Supracondylar femoral (SCF) fractures in adult animals present significantly greater challenges to veterinary orthopedists than do fractures in immature animals in which the bone breaks are usually type I or II Salter-Harris physeal fractures. In adult animals, SCF fractures are often unstable because of their distal position and propensity to be comminuted. Because of the composition of the distal femur, minimal bone stock is usually available for implant placement. As a result, traditional implants such as intramedullary pins and dynamic compression plates may not be adequate to stabilize fracture forces. A range of available implants offers additional approaches to the management of this relatively uncommon fracture

Use of a lateral tibial head buttress plate to repair a tibial fracture in a labrador retriever

A lateral tibial head buttress plate designed for human beings was used to repair a highly comminuted tibial fracture in a two-year-old male labrador retriever caused by a gunshot wound. The plate was placed in a bridging fashion to provide minimal disruption of the fracture site and minimise surgical time. THE lateral tibial head buttress (LTHB) plate is a tibial plate used in human beings. It has an expanded metaphyseal section to improve the fixation of the tibial plateau. It has also been used to repair supracondylar femoral fractures (Schatzker and Tile 1996) and distal humeral shaft fractures (Levy and others 2005). It is 3·8 mm thick and 14 mm wide. The plate is available with a curved right or left proximal flare with a maximum width of 26 mm. The flared portion of the plate is designed to correspond to the proximal aspect of the human tibia, and contains one oval and three round screw holes so that the plate can be applied in compression. The plate is available with five to 13 shaft holes. Its use in dogs has been reported in the repair of supracondylar and distal femoral fractures (Dueland and VanEnkevort 1995, Glyde and others 2003). Gunshot injuries can cause extensive bony and soft tissue trauma as a result of crushing and laceration, the generation of shock waves, cavitation, and the formation of secondary missiles consisting of bone fragments. These cause major vascular and soft tissue damage, resulting in long healing times. The fixation of gunshot fractures requires rigid, long-lasting stabilisation. This paper reports the use of an LTHB plate in the repair of a tibial fracture in a dog

The effect of intramedullary pin size and plate working length on plate strain in locking compression plate-rod constructs under axial load

Objective: To investigate the effect of intramedullary pin size and plate working length on plate strain in locking compression plate-rod constructs. Methods: A synthetic bone model with a 40 mm fracture gap was used. Locking compression plates with monocortical locking screws were tested with no pin (LCP-Mono) and intramedullary pins of 20% (LCPR-20), 30% (LCPR-30) and 40% (LCPR-40) of intramedullary diameter. Two screws per fragment modelled a long (8-hole) and short (4-hole) plate working length. Strain responses to axial compression were recorded at six regions of the plate via three-dimensional digital image correlation. Results: The addition of a pin of any size provided a significant decrease in plate strain. For the long working length, LCPR-30 and LCPR-40 had significantly lower strain than the LCPR-20, and plate strain was significantly higher adjacent to the screw closest to the fracture site. For the short working length, there was no significant difference in strain across any LCPR constructs or at any region of the plate. Plate strain was significantly lower for the short working length compared to the long working length for the LCP-Mono and LCPR-20 constructs, but not for the LCPR-30 and LCPR-40 constructs. Clinical significance: The increase in plate strain encountered with a long working length can be overcome by the use of a pin of 30–40% intramedullary diameter. Where placement of a large diameter pin is not possible, screws should be placed as close to the fracture gap as possible to minimize plate strain and distribute it more evenly over the plate

The effect of tibial plateau levelling osteotomy on stifle extensor mechanism load: A canine ex vivo study

OBJECTIVE: To evaluate the effect of tibial plateau levelling osteotomy on stifle extensor mechanism load in an ex vivo cruciate-intact canine cadaveric model. STUDY DESIGN: Ex vivo mechanical testing study. ANIMALS: Cadaveric canine pelvic limbs (n = 6). MATERIALS AND METHODS: A 21-mm tibial radial osteotomy was performed on pelvic limbs (n = 6) prior to being mounted into a load-bearing limb press. The proximal tibial segment was incrementally rotated until the anatomical tibial plateau angle had been rotated to at least 1°. The proportional change in stifle extensor mechanism load between the anatomical tibial plateau angle and the neutralized (∼6.5 degrees) and over-rotated (∼1°) tibial plateau angle was analysed using a one-sample t-test against a null hypothesis of no change. A p-value ≤0.05 was considered significant. RESULTS: There was no significant change in the stifle extensor mechanism load from the anatomical tibial plateau angle (308 N [261-355 N]) to the neutralized tibial plateau angle (313 N [254-372 N]; p =.81), or from the anatomical tibial plateau angle to the over-rotated tibial plateau angle (303 N [254-352 N; p = 0.67). CONCLUSION: Tibial plateau levelling osteotomy does not significantly alter stifle extensor mechanism load at either a neutralized or over-rotated tibial plateau angle in our cruciate-intact model

Partial rupture of the cranial cruciate ligament in 13 dogs: Clinical, radiological, clinicopathological and histopathological feature

Objective To report the clinical, radiological, clinicopathological and histopathological features of the stifle joints of dogs with partial rupture of the cranial cruciate ligament (PR). Procedure Information on patient data and results of physical, radiological and surgical examination, synovial fluid and histopathological analysis from stifle joints of 13 dogs treated for PR at the University of Melbourne Veterinary Clinic and Hospital was evaluated. Results Rupture of the craniomedial band (CMB) was most common. In five dogs a cranial drawer sign was present in flexion only and was absent in one dog. Ipsilateral stifle joint effusion and osteoarthritis were present in 11 cases. Contralateral osteoarthritis was present in ten cases. Synovial fluid was non-inflammatory (mean total cell count 2.0 × 109/L, SEM 0.2, range 1.1 to 2.7; mean neutrophil percentage 5.5, SEM 2.95, range 0 to 30). Mild synovitis was present on histopathological examination with mild diffuse plasmacytic infiltration of the subsynovial tissue being most common. No evidence of primary immune-mediated arthropathy was identified. Conclusions Testing for cranial drawer with the stifle joint in a flexed position will increase the sensitivity of the cranial drawer test in diagnosing PR. Absence of a cranial drawer sign does not rule out PR. Abnormalities consistent with chronic degenerative joint disease are apparent in the majority of stifle joints with PR. Ipsilateral stifle joint osteoarthritis and effusion and contralateral osteoarthritis are likely to be present. Synovial fluid analysis is consistent with a non-inflammatory degenerative arthropathy. Mild diffuse plasmacytic or lymphoplasmacytic synovitis is typical of PR

Reduction of the A-Frame angle of incline does not change the maximum carpal joint extension angle in agility dogs entering the A-Frame

Objective This article aims to investigate the effect of a decrease in the A-frame angle of incline on the highest carpal extension angle in agility dogs. Methods Kinematic gait analysis (two-dimensional) measuring carpal extension was performed on 40 dogs entering the A-frame at 3 angles of incline: 40° (standard), 35° and 30°. The highest carpal extension angle from three trials at each incline was examined for a significant effect of A-frame angle with height, body weight and velocity included as covariates. Results There was no significant effect of A-frame angle on the highest carpal joint extension angle for the first or second limb. The adjusted mean carpal extension angle for the first limb at 40° was 64° [95% confidence interval (CI), 60–68), at 35° was 61° (95% CI, 57–65) and at 30° was 62° (95% CI, 59–65). The raw mean carpal extension angle for all dogs across all A-frame angles for the first limb was 62° (95% CI, 60–64) and the second limb was 61° (95% CI, 59–63). Clinical Significance Decreasing the A-frame angle of incline from 40° to 30° did not result in reduced carpal extension angles. The failure to find a difference and the narrow CI of the carpal angles may indicate that the physiologic limits of carpal extension were reached at all A-frame angles

Fisioterapia após substituição artroscópica do ligamento cruzado cranial em cães: I - avaliação clínica, radiográfica e ultrassonográfica Physiotherapy after arthroscopic repair of the cranial cruciate ligament in dogs: I - clinical, radiographic, and ultrasonographic evaluation

Foram avaliadas a aplicabilidade da cirurgia artroscópica na substituição do ligamento cruzado cranial (LCC) e o efeito da fisioterapia pós-operatória, por meio de exames clínicos, radiográficos e ultrassonográficos, em 16 cães sem raça definida, machos, com pesos entre 19,2 e 26,3kg, submetidos à ruptura experimental do LCC e subsequente substituição deste ligamento pelo enxerto autógeno da fascia lata. Os animais foram distribuídos em dois grupos de oito cada: no grupo I os cães foram submetidos ao programa de fisioterapia pós-operatória e no grupo II à imobilização temporária do membro. Por meio dos exames citados, não foram verificadas diferenças significativas entre os dois grupos, e ambos demonstraram sinais de processo articular degenerativo. A função do membro foi avaliada com auxílio da plataforma de força, e os animais do grupo I apresentaram melhor apoio do membro operado durante o período de reabilitação. Conclui-se que a cirurgia artroscópica é uma técnica eficaz para substituição do LCC em cães, apesar de não impedir o desenvolvimento da doença articular degenerativa, e que a fisioterapia permite recuperação mais rápida no apoio do membro durante o período de reabilitação.<br>The reconstruction of experimentally ruptured cranial cruciate ligament (CCL) under arthroscopic guidance and the effects of an early postoperative rehabilitation program by clinical, radiographic, and ultrasonographic exams were evaluated. Sixteen male mongrel dogs weighing from 19.2 to 26.3kg had the CCL experimentally ruptured and the stifle joint was stabilized by the use of an intracapsular arthroscopical technique with fascia lata as an autogenous graft. Eight dogs were included in a postoperative physiotherapy group and the other eight in a temporary immobilization group. From serial clinical, radiographic, and ultrasonographic examinations, no differences between groups were observed, although all dogs had showed signs of degenerative joint disease. Limb function was determined after surgery using force platform analysis, and the animals from physiotherapy group had significantly better results during rehabilitation period. It can be concluded that arthroscopic surgery for reconstruction of the cranial cruciate ligament is an efficient method to be used in dogs, in spite of not preventing the degenerative joint disease, and the physiotherapy has beneficial effects on early limb function during the rehabilitation period

Vídeo-artroscopia da articulação fêmoro-tíbio-patelar em cães após secção do ligamento cruzado cranial guiada por artroscopia Videoarthroscopy of the stifle joint in dogs after cranial cruciate ligament rupture guided by arthroscopy

Avaliaram-se e classificaram-se por meio da vídeo-artroscopia as alterações da articulação fêmoro-tíbio-patelar (FTP), 21 dias após secção experimental do ligamento cruzado cranial (LCCr) em cães, tendo como referência os parâmetros encontrados no exame artroscópico imediatamente anterior à secção. Ao exame artroscópico, foi possível visibilizar os cotos remanescentes do LCCr e as alterações articulares, como aumento da vascularização, aumento das vilosidades na membrana sinovial, bem como fibrilação e osteófitos, principalmente nas bordas trocleares do fêmur. Os resultados sugerem que a artroscopia é um método preciso de avaliação macroscópica dos tecidos articulares moles e duros.<br>By the use of videoarthroscopy, the changes of the stifle joint after experimental rupture of cranial cruciate ligament (CCL) in dogs were evaluated and classified, based on the parameters found at the arthroscopic examination right before the rupture. By the arthroscopic examination, it was possible to visualize the remainings of the CCL and joint changes such as increase of the vascularity and synovial proliferation increase in the synovial membranes, as well as fibrillation and irregularities on the joint surfaces and osteophyte formation, mainly on the trochlear ridges. The results suggest that arthroscopy is a precise method for macroscopic evaluation of the smooth and bone joint tissue

Fisioterapia após substituição artroscópica do ligamento cruzado cranial em cães: II - avaliação artroscópica e anatomopatológica Physiotherapy after arthroscopic repair of the cranial cruciate ligament in dogs: II - Arthroscopic and anatomopathological evaluations

Avaliou-se o enxerto da fascia lata na substituição artroscópica do ligamento cruzado cranial (LCC), realizou-se a caracterização histológica do enxerto e da interface enxerto-osso e avaliou-se, por meio de exames artroscópicos e anatomopatológicos, o efeito da fisioterapia pós-operatória. Foram utilizados 16 cães, sem raça definida, machos, pesando entre 19,2 e 26,3kg, submetidos à ruptura experimental do LCC e subsequente substituição artroscópica desse ligamento pelo enxerto autógeno da fascia lata. Os animais foram distribuídos em dois grupos de oito cada: no grupo I, os cães foram submetidos ao programa de fisioterapia pós-operatória e, no grupo II, à imobilização temporária do membro. Os exames artroscópicos e histológicos mostraram alterações articulares sugestivas de processo degenerativo aos 60 dias após a cirurgia, que se apresentavam mais acentuadas nos cães do grupo II. Na análise histológica do enxerto, observou-se reorganização das fibras colágenas, que ocorreu de forma mais intensa e precoce nos animais do grupo I. Houve progressiva integração das fibras colágenas na interface enxerto-osso. Conclui-se que é viável utilizar a fascia lata como substituto do LCC por cirurgia artroscópica, que o enxerto sofre processos de ligamentação e de osteointegração, e que a fisioterapia reduz a progressão das alterações degenerativas e incentiva o processo de ligamentação do enxerto.<br>The fascia lata graft in the arthroscopic reconstruction of the cranial cruciate ligament (CCL), the histological characteristics of the graft and the graft-bone interface, and the effects of postoperative physiotherapy by arthroscopic and anatomopathological exams were evaluated. Sixteen male mongrel dogs weighing from 19.2 to 26.3kg had the CCL experimentally ruptured and the stifle joint was stabilized by arthroscopical technique with fascia lata as an autogenous graft. Eight dogs were included in a postoperative physiotherapy group and the other eight in a temporary immobilization group. Arthroscopic and histological examinations showed articular lesions consistent with degenerative joint disease at 60 days after surgery, which was more severe in dogs from the temporary immobilization group. From histological studies, the graft underwent a collagenic reorganization process that was more intense and earlier in dogs from the physiotherapy group. There was a progressive establishment of collagen fiber continuity in the graft-bone interface. It can be concluded that fascia lata graft can be used to replace the CCL by arthroscopic surgery, the graft undergo a ligamentization and osteointegration process, and the postoperative physiotherapy decrease the degenerative joint disease progression and stimulate the ligamentization of the graft

Slowing the progression of age-related hearing loss: Rationale and study design of the ASPIRIN in HEARING, retinal vessels imaging and neurocognition in older generations (ASPREE-HEARING) trial

© 2015. Background: Age-related hearing loss (ARHL) is a leading cause of disability in the elderly. Low-grade inflammation and microvessel pathology may be responsible for initiating or exacerbating some of the hearing loss associated with aging. A growing body of evidence demonstrates an association of hearing loss with cognitive decline. A shared etiological pathway may include a role of inflammation, alongside vascular determinants. The ASPREE-HEARING study aims to determine whether low-dose aspirin decreases the progression of ARHL, and if so, whether this decrease in progression is also associated with retinal microvascular changes and/or greater preservation of cognitive function. Design and methods: A three year double-blind, randomized controlled trial of oral 100. mg enteric-coated aspirin or matching placebo, enrolling 1262 Australians aged =. 70. years with normal cognitive function and no overt cardiovascular disease. The primary outcome is the change in mean pure tone average hearing threshold (decibels) in the better ear, over a 3-year period. Secondary outcomes consist of changes in retinal microvascular indicators, and changes in cognitive function. Participants are recruited from a larger trial, ASPirin in Reducing Events in the Elderly (ASPREE), which is designed to assess whether daily low dose aspirin will extend disability-free life. Discussion: ASPREE-HEARING will determine whether aspirin slows development or progression of ARHL, and will interrogate the relationship between inflammatory and microvascular mechanisms that may underlie the effects of aspirin on ARHL. This study will improve understanding of the patterns of comorbidity with, and the relationships between, aging and ARHL, alongside modeling the impacts of ARHL