Mechanical osteoarthritis of the hip in a one medicine concept: a narrative review.

Human and veterinary medicine have historically presented many medical areas of potential synergy and convergence. Mechanical osteoarthritis (MOA) is characterized by a gradual complex imbalance between cartilage production, loss, and derangement. Any joint instability that results in an abnormal overload of the joint surface can trigger MOA. As MOA has a prevailing mechanical aetiology, treatment effectiveness can only be accomplished if altered joint mechanics and mechanosensitive pathways are normalized and restored. Otherwise, the inflammatory cascade of osteoarthritis will be initiated, and the changes may become irreversible. The management of the disease using non-steroidal anti-inflammatory drugs, analgesics, physical therapy, diet changes, or nutraceuticals is conservative and less effective. MOA is a determinant factor for the development of hip dysplasia in both humans and dogs. Hip dysplasia is a hereditary disease with a high incidence and, therefore, of great clinical importance due to the associated discomfort and significant functional limitations. Furthermore, on account of analogous human and canine hip dysplasia disease and under the One Medicine concept, unifying veterinary and human research could improve the well-being and health of both species, increasing the acknowledgement of shared diseases. Great success has been accomplished in humans regarding preventive conservative management of hip dysplasia and following One Medicine concept, similar measures would benefit dogs. Moreover, animal models have long been used to better understand the different diseases' mechanisms. Current research in animal models was addressed and the role of rabbit models in pathophysiologic studies and of the dog as a spontaneous animal model were highlighted, denoting the inexistence of rabbit functional models to investigate therapeutic approaches in hip MOA.

Distraction index measurement on the dog's hip joint using a dedicated software / [Medição do índice de distração da anca do cão usando um software especial]

The aim of this study was to test the accuracy of a new automated computer software tool for the assessment of passive hip laxity. The hip laxity was estimated using the dedicated computer software by two blinded evaluators, one previously trained and one without specific training for distraction index measurement, in two independent sessions using 230 hip joints from 115 dogs that underwent screening for passive hip laxity using the distraction view. Previously, all of these radiographs were sent to PennHIP Analysis Center for an official distraction index record. The measurement repeatability of the two sessions was adequate for both evaluators. The reproducibility of the official distraction index measurement, mean distraction index±standard deviation 0.44±0.15, was adequate (P>0.05) for the trained evaluator, 0.44±0.15, and non-adequate (P<0.05), for the non-trained evaluator 0.47±0.17. The distraction index measurement tool proposed can be used with confidence for hip laxity evaluation by trained evaluators, as it provided good repeatability and reproducibility of official reports. The simplicity of the process described leads to a less time-consuming and more affordable procedure.(AU)

O objetivo deste estudo foi testar a viabilidade de uma nova ferramenta de software informático para avaliação da lassitude articular passiva da articulação coxofemoral. A lassitude articular da articulação coxofemoral foi estimada usando-se um programa informático especial, desenvolvido para o efeito, por dois avaliadores, um com treino prévio e outro não treinado, na medição do índice de distração, em duas sessões independentes, utilizando-se 230 articulações coxofemorais de 115 cães, as quais efetuaram o rastreio de displasia coxofemoral realizando a projeção de distração da articulação coxofemoral. Previamente, todas as radiografias foram enviadas para o PennHIP Analysis Center, para se obter uma medida oficial do índice de distração. A repetibilidade das medições das duas sessões foi adequada para ambos os avaliadores. A reprodutibilidade do índice de distração oficial, média±desvio-padrão 0,44±0,15, foi adequada (P>0,05) para o avaliador treinado, 0,44±0,15, e não adequada (P>0,05) para o avaliador não treinado, 0,47±0,17. A ferramenta de medição do índice de distração proposta pode ser usada com segurança na medição do índice de distração por avaliadores treinados, uma vez que mostra uma adequada repetibilidade e reprodutibilidade das medições oficiais do índice de distração. A simplicidade do processo apresentado torna-o menos demorado e mais econômico.(AU)

Long-term exercise training as a modulator of mammary cancer vascularization.

BACKGROUND: Breast cancer remains a leading cause of death by cancer worldwide. It is commonly accepted that angiogenesis and the expression of angiogenic factors such as vascular endothelial growth factor-A (VEGF-A) is associated with the increased risk of metastasis and poor patient outcome. OBJECTIVE: This work aimed to evaluate the effects of long-term exercise training on the growth and vascularization of mammary tumors in a rat model. MATERIALS AND METHODS: Fifty female Sprague-Dawley rats were divided into four groups: two N-methyl-N-nitrosourea (MNU)-exposed groups (exercised and sedentary) and two control groups (exercised and sedentary). MNU was administered once, intraperitoneally at 7 weeks-old. Animals were then exercised on a treadmill for 35 weeks. Mammary tumors were evaluated using thermography, ultrasonography [Power Doppler (PDI), B Flow and contrast-enhanced ultrasound (CEUS)], and immunohistochemistry (VEGF-A). RESULTS: Both, MNU sedentary and exercised groups showed 100% of tumor incidence, but exercised animals showed less tumors with an increased latency period. Exercise training also enhanced VEGF-A immunoexpression and vascularization (microvessel density, MVD) (p<0.05), and reduced histological aggressiveness. Ultrasound and thermal imaging analysis confirmed the enhanced vascularization of tumors on exercised animals. CONCLUSION: Long-term exercise training increased VEGF-A expression, leading to enhanced tumor vascularization and reduced tumor burden, multiplicity and histological aggressiveness.

MNU-induced rat mammary carcinomas: immunohistology and estrogen receptor expression.

Environmental exposure to nitrosamines is associated with the development of cancer in a variety of target organs. One such carcinogen, N-methyl-N-nitrosurea (MNU), has long been used to induce mammary tumors in rats, which provide a useful model to study mammary carcinogenesis. However, some poorly clarified issues remain, such as the lack of a clear description of morphological patterns of tumors and the distribution and role of estrogen receptors (ERs) during tumor progression, as tumors overexpressing ERs show a paradoxical tendency to recur after ovariectomy. Mammary carcinomas were induced in Sprague-Dawley rats using MNU. The tumors were studied histologically and distribution of smooth muscle actin and ERs was studied immunohistochemically. All tumors presented both an epithelial and a myoepithelial component, demonstrated by immunohistochemical detection of smooth muscle actin. Tumors showed distinct histological patterns: well-differentiated papillary and adenoid areas and poorly differentiated solid and spindle-cell foci. Overexpression of ERs (>75% of labelled cells vs. 0-75% in control tissue) occurred in papillary and adenoid areas but not in solid and spindle-cell foci. Poorly differentiated tumor foci are likely to represent a more advanced, estrogen-independent phase in cancer progression and constitute the basis for tumor recurrence after ovariectomy.

Ultrasonographic, thermographic and histologic evaluation of MNU-induced mammary tumors in female Sprague-Dawley rats.

BACKGROUND: As the worldwide breast cancer burden increases, non-invasive tools, such as ultrasonography and thermography are being increasingly sought after. N-methyl-N-nitrosourea-induced rat mammary tumors are important tools to investigate the usefulness of such imaging techniques. OBJECTIVE: This study aimed to integrate both ultrasonographic and thermographic approaches to the vascularization and the superficial temperature of chemically-induced rat mammary tumors. MATERIALS AND METHODS: Twenty-five female Sprague-Dawley rats were divided into two groups: group I (intraperitoneally administered with N-methyl-N-nitrosourea) and group II (control group). Thirty-five weeks after the administration of the carcinogen, mammary tumors were evaluated using Power Doppler, B Flow and Contrast-enhanced ultrasound, thermography and histology analyses. RESULTS: Group I animals showed an average of 2.5 mammary tumors per animal, mostly papillary and cribriform non-invasive carcinomas. B Flow detected higher counts of colour pixels than Power Doppler. Contrast-enhanced ultrasound analysis showed a centripetal enhancement order of contrast agent and clear margins. Maximum tumor temperature and thermal amplitude determined by thermography were significantly correlated with tumor volume and with color pixel density, determined by Power Doppler. CONCLUSION: B Flow was more sensitive than Power Doppler in detecting tumor vessels, but Power Doppler correlates with thermographic data concerning superficial temperature and may reflect tumor angiogenesis.

Sub-acute and chronic MRI findings in bilateral canine fibrotic contracture of the infraspinatus muscle.

A six-year-old, 30-kg female German pointer dog was presented for examination with a history of pre-existing right-forelimb lameness and more recent (3 months) persistent lameness in the left-forelimb. Physical examination revealed mild left-forelimb lameness and a mild circumduction movement. There were no signs of pain or crepitation detected during manipulation of the shoulders, but the animal was unable to fully flex both glenohumeral joints. Magnetic resonance imaging, using fast recovery fast spin echo T2-weighted and fat saturated proton density sequences, revealed abnormal heterogeneous hypointensity in the right infraspinatus muscle and a heterogeneous hyperintense area in the left infraspinatus muscle. Surgical treatment consisting of a bilateral infraspinatus tenectomy resulted in improved limb function. Histopathological examination demonstrated tissue changes in the right infraspinatus, characterised by myofibre degeneration and fibrosis, compatible with a chronic degenerative process, while changes in the left infraspinatus muscle were characterised by variable degrees of fibre degeneration, haemorrhage and interstitial oedema.

Morphometric assessment of the hip joint in the Estrela Mountain Dog breed.

OBJECTIVES: To study the radiographic projected hip parameters of the proximal femur and acetabulum in young and adult Estrela Mountain Dogs with normal and abnormal hip joints. The parameters evaluated were: femoral angles of inclination and anteversion (FAI and FAA), femoral neck length and width (FNL and FNW), acetabular depth (AD) and acetabular angle of retrotorsion (AAR). METHODS: Five hundred and twenty-five standard hip-extended ventrodorsal radiographic views and 622 mediolateral views of the right and left femur were used to measure the FAI, FAA, FNL, FNW, AD, AAR and modified AAR (mAAR). RESULTS: The FAI decreased in adult dysplastic dogs, in females and in right femora; FAA decreased with age; FNL was characterized by a greater relative size in normal adult animals; FNW was greater in abnormal hips in young and adult animals; AD was less in adult dysplastic dogs and in right hips; AAR was similar in the studied groups; mAAR was greater in abnormal hips and in left hips. CLINICAL SIGNIFICANCE: The data may be used in future studies, which compare this breed to others. Morphological variations in femoral neck and acetabular morphometric parameters were present, and these variables in dogs with different ages and with hips in varying states of health should not be compared.

Contrast-enhanced dynamic magnetic resonance nephrography in healthy dogs.

Twenty-three healthy mixed-breed male adult dogs were examined using serial magnetic resonance (MR) renograms. The images were obtained using a dynamic gradient-echo, fast SPGR, T1-weighted sequence and low doses of gadolinium chelates (0.025 mmol/kg). Time-intensity curves were obtained to assess typical urinary excretion parameters, namely, time to vascular peak (TVP), time to vascular drop (TVD), time to glomerular peak (TGP), parenchymal phase length (PPL), gradient of parenchymal phase (GPP) and pattern of excretory segment. The mean TVP, TVD, TGP and PPL were 31.6±11.8, 43.4±11.2, 154.0±36.2 and 115.2±37.7s, respectively. The GPP was 24.1±8.6% of signal intensity per min. The excretory segment was concave in all cases, and at the end of the examination, 87.1% of kidneys had shown a reduction in signal intensity of 50%. This MR nephrography protocol can provide adequate time-intensity curve parameters for the urinary system of dogs, offers excellent anatomical detail, and represents an alternative to radionuclide nephrography.

Diagnosis, genetic control and preventive management of canine hip dysplasia: a review.

Despite expensive screening and breeding programmes, hip dysplasia (HD) continues to be one of the most common orthopaedic diseases in dogs. The vast majority of dogs afflicted with HD show minimal to no clinical signs, but it can also be a highly debilitating condition for both working and pet dogs. Hip joint laxity is considered a major risk factor for the development of degenerative joint disease and a definitive diagnosis is made if characteristic signs are evident on a ventrodorsal view of the pelvis. Early prediction of the condition can be made using stress radiographic techniques to evaluate the passive hip laxity. The diagnosis of HD may be used for the purpose of selecting breeding stock or to decide on the best treatment approach. Breeding programmes based on individual dog phenotypes have been ineffective and a selection procedure based on breeding value (BV) estimation is recommended. Traditional conservative and surgical treatment approaches are reserved for dogs with overt clinical signs of the disease but such treatments can be expensive and aggressive, and are often ineffective in eliminating clinical signs or subluxation and in preventing the development of degenerative joint disease. The implementation of breeding programmes based on BVs and further research into early prediction/diagnosis of HD and effective preventive treatment approaches are essential.

Hip dysplasia in Estrela mountain dogs: prevalence and genetic trends 1991-2005.

Three hundred and thirteen Estrela mountain dogs were examined for hip dysplasia (HD) using the standard ventrodorsal hip extended view, and graded into five categories (A, B, C, D and E) using the Fédération Cynologique Internationale's (FCI) scoring system. The Ortolani method was performed to evaluate hip joint laxity. Pedigree information was obtained from the Portuguese Kennel Club and the genetic trend was evaluated by calculating the mean breeding values (BVs) for the last 15 years, using the threshold model. HD was found in 66% of the dogs. There was low-moderate correlation between the results of the Ortolani test and FCI hip scores (r(s)=0.386; P<0.001). Grades of hip dysplasia were equal in both males and females (P=0.14) and in the animals' right and left sides (P=0.51). The mean BVs for HD were stable in dogs born between 1991 and 2003, and showed an improvement in 2004 and 2005. The data confirm the high prevalence and severity of HD in predisposed breeds that do not have breeding programmes in place. It also confirms an initial favourable change in BVs that is a likely consequence of the voluntary radiographic hip-screening programme.

Early hip laxity examination in predicting moderate and severe hip dysplasia in Estrela mountain dog.

OBJECTIVES: To determine the reliability of early passive hip laxity examination in predicting moderate and severe hip dysplasia. METHODS: The passive hip laxity of 104 Estrela Mountain dogs was evaluated using the Ortolani method, conventional hip-extended radiography and the PennHIP method, when the animals were between four and 12 months of age. After the age of one, dogs were re-examined for hip dysplasia using the Fédération Cynologique Internationale scoring system. The passive hip laxity results were subsequently compared with the Fédération Cynologique Internationale scores for sensitivity, specificity, positive predictive value, negative predictive value and accuracy. RESULTS: The PennHIP method achieved the best results in specificity (93 per cent), positive predictive value (91 per cent) and accuracy (88 per cent), and the Ortolani method was the best in sensitivity (92 per cent) and negative predictive value (92 per cent). CLINICAL SIGNIFICANCE: The Fédération Cynologique Internationale grades D and E can be predicted with confidence even before animals are one year old.

Mechanical devices to help in PennHIP examination.

A modified PennHIP procedure (MPP), using specific mechanical holding devices, was used on 70 dogs and compared to the standard PennHIP method (SPM) used on 39 dogs, in terms of technical effectiveness and the mean number of essential individuals within the X-ray room (EIXRR). The data using the Chi-squared test were consistent with the null hypothesis that the technical effectiveness was equal in the groups under investigation (P > 0.05). On the contrary, using the two-sample unpaired t-test the null hypothesis, that the mean EIXRR was equal, was rejected (P < 0.001). The estimated EIXRR was 3.4 +/- 0.7 and 5.7 +/- 1.2 (mean +/- SD) for MPP and SPM, respectively. In conclusion, the MPP needs fewer EIXXR than the SPM and complies with the new recommendations in X-ray protection, which introduce the ALARA (as-low-as-reasonably-achievable) idea.

Comparison of estimates of hip dysplasia genetic parameters in Estrela Mountain Dog using linear and threshold models.

Genetic parameters, breeding values, and genetic trends of hip dysplasia in Estrela Mountain Dogs were estimated using a linear model (LM) and a threshold model (TM). A database with 313 animals was used. Right and left hip joints were individually scored, according to the Fédération Cynologic Internationale grading rules of the canine hip dysplasia system, as normal (1), borderline (2), slight (3), moderate (4), and severe (5 and 6). The estimate of repeatability was lower in LM (0.86) than in TM (0.90). The same tendency was verified with the heritability because its estimate in LM was 0.38 and in TM was 0.43. However, these results did not establish any statistical differences between the models. The genetic trend of canine hip dysplasia for LM and TM showed a similarity in shape, but considerable individual differences were found in the EBV ranking lists. Therefore, the selection of breeding animals would not be the same with the 2 methodologies. To select the best method for genetic evaluation of hip dysplasia, further studies using more data and other dog breeds are required.

Measurement of the femoral neck anteversion angle in the dog using computed tomography.

Simple and accurate limb and pelvic conformation evaluation using computed tomography (CT) can be useful in planning canine hip dysplasia (CHD) treatment and in helping to understand the pathogenesis of osteoarthritis and CHD. The objectives of this study were to describe a new method for femoral neck anteversion angle (FNA-angle) measurement in CT, and to compare it to the established radiographic standard biplanar method. The hips of 23 Estrela Mountain Dogs were evaluated using radiography and CT and their FNA-angles were determined by performing two CT examinations and with one radiographic measurement session. The intra-class correlation coefficient (ICC) was used to evaluate the repeatability (agreement between the two CT sessions, ICC=0.92) and reproducibility (agreement between each CT and radiographic session, ICC=0.91 in both cases) of the CT FNA-angle measurement method. This study suggests that CT FNA-angle measurement method is reliable and can be used in CT hip studies with confidence.

Repeatability and reproducibility of distraction indices in PennHIP examinations of the hip joint in dogs.

Repeatability and reproducibility of Distraction Index (DI) measurements in the PennHIP method were evaluated in 100 dogs. The PennHIP distraction views sent to the PennHIP Analysis Center (PAC) were duplicated, digitalised, and identified with a code, and an adequate computer software was used for DI measurements. One examiner performed two DI measurement sessions, evaluating individually 200 hip joints. The scoring repeatability and reproducibility were estimated calculating the Intraclass Correlation Coefficient (ICC) between the two DI measurement sessions and between the second DI measurement session and the DI in PAC reports, respectively. The ICC for repeatability was 0.97 [95% confidence interval (CI), 0.96 to 0.98], and the ICC for reproducibility was 0.95 (95% CI, 0.93 to 0.96). The results suggest that the DI measurement method described is repeatable and can reproduce the PAC reports with confidence. Distraction indices measured in different PennHIP studies, using this DI measurement method and performed by trained researchers, can be considered interchangeable.

Opisthorchis felineus in cat: case report

Opisthorchis felineus foi encontrado em um gato admitido no Hospital Veterinário da Universidade de Trás-os-Montes e Alto Douro. No momento de admissão, o animal apresentava-se em estado de choque, com hipotermia, desidratação e mucosas pálidas. As análises hematológicas revelaram linfopenia, eosinofilia e anemia moderada. A necrópsia observou-se distensão da vesícula biliar e intensa infestação parasitária no fígado. O estudo morfológico do parasita revelou tratar-se de Opisthorchis felineus.