Comparative investigations on the upper respiratory tract in Norwich terriers, brachycephalic and mesaticephalic dogs.

For some time Norwich terriers have been known to suffer from respiratory problems. In order to assign this weakness to a pathophysiology, 23 terriers were examined clinically, with laryngoscope and with rhinomanometry. In addition their skulls were dimensioned on radiographs. Widened nostrils, overlong soft palates and the everted laryngeal pouches were consistent with brachycephalic syndrome. Resistance values in the nasal passage corresponded to the appearance in brachycephalic dogs. Skull measurements gave inconsistent results, because length to width ratios and craniofacial angles denoted mesaticephaly, whereas the facial to cranial length ratios (S-index = 0.65) lay in the brachycephalic sector. It can be concluded, that the Norwich terrier breed is in transition towards brachycephaly with some individual dogs already suffering from the brachycephalic syndrome. Breeders are requested to introduce necessary counter measures.

On sait depuis longtemps déjà que le Norwich Terrier souffre de plus en plus de problèmes respiratoires. Afin de pouvoir donner une explication pathophysiologique à ces problèmes, on a examiné 23 Norvich Terriers sur le plan clinique, laryngoscopique, rhino-manométrique ainsi qu'avec des radiographies du crâne. Des narines larges, un voile du palais trop long et des ventricules laryngés éversés, de même que des mesures de résistance augmentées dans les conduits nasaux correspondaient à l'image du syndrome brachycéphale. Les mesures du crâne présentaient un tableau non uniforme. L'index longueur-largeur et l'angle cranio-facial correspondaient à ceux de chiens mésocéphales, alors que l'index splanchnocrâne-neurocrâne (Index S de 0.65) était clairement dans la zone du brachicéphalisme. On peut en déduire que le Norwich Terrier se trouve sur le chemin du brachicéphalisme et que certains chiens souffrent déjà d'un syndrome brachycéphale. Les éleveurs doivent donc prendre des mesures pour lutter contre cette évolution.

Endoprosthesis (EN) in frontlimb-sparing surgery for distal radial tumours in the dog: preliminary results.

In veterinary medicine, limb-sparing techniques are most implemented when the uninvolved limbs are affected by other orthopaedic or neurological disorders, in large breeds or when the owner declines amputation. This report describes the surgical technique used for implantation of an endoprosthesis following tumour resection in the distal radius in 3 dogs using both standard and angle-stable plates. Endoprosthesis offers an easy and readily available surgical alternative to cortical allografts. Despite post-operative complications, this technique resulted in a good quality of life in all 3 dogs.

Loss of implant-bone interface following distal radial locking-plate endoprosthesis limb-sparing surgery in a dog.

An eight-year-old, neutered female Rottweiler was presented with lameness of seven days duration. Radiographs were consistent with a distal radial bone tumour. Limb-sparing surgery was performed using a commercially available endoprosthesis with a locking bone plate. Histopathological examination of the resected bone revealed an intraosseous fibrosarcoma, and postoperative adjuvant chemotherapy was initiated three weeks after surgery. Despite initial satisfactory limb function, lameness worsened four months after surgery. Radiographs revealed large areas of bone lysis around the proximal and distal screws, leading to significant resorption of the radius and radial carpal bone with subsequent construct failure. Further treatment was declined by the owner and the dog was subsequently euthanased. This case illustrates that implant failure is not necessarily averted by the use of locking (compared with non-locking) implants combined with an endoprosthesis to treat distal radial tumours in dogs.

Effect of dog breed and body conformation on vertical ground reaction forces, impulses, and stance times.

OBJECTIVES: To assess whether fully normalised vertical ground reaction forces and stance times obtained at a trot depend on dog breed or body conformations. METHODS: Peak vertical forces (PVF), vertical impulses (VI), stance times (ST), and ratio of forelimb impulse to total impulse (RVI) of 54 dogs of seven different breeds were normalised to body weight and body size according to the theory of dynamic similarity, and were tested for differences between breeds. Breeds were Borzoi, Bernese Mountain dog, Great Dane, Labrador Retriever, Landseer, Rhodesian Ridgeback, and Rottweiler. Body length ratio (BLR) and body mass index (BMI) were also compared between breeds. RESULTS: Significant differences between breeds were found for the normalised forelimb PVF, VI and ST, and hindlimb PVF. Looking at individual breeds, it was most evident that Borzois had a lower forelimb VI, and a higher hindlimb PVF than the other breeds. This resulted in Borzois having a lower RVI compared to other dogs, indicating a more caudally located centre of gravity. Only a few differences in gait parameters were found between other dog breeds. The BMI was significantly lower in Borzois than in other breeds, but was otherwise not associated with gait parameters. CLINICAL SIGNIFICANCE: Force plate data of dogs of different breeds are not necessarily comparable, even after full normalisation to body weight and body size. Group comparisons should only be made when the groups consist of breeds with similar body conformations.

Fixation of pelvic floor fractures in cats.

OBJECTIVES: To retrospectively evaluate the outcome of internal fixation of trauma- related pelvic floor fractures using a ventral abdominal approach in cats. METHODS: Clinical examination and radiographic findings at presentation, after surgery, and at follow-up were assessed. Information gathered included concurrent injuries, surgical technique used, lameness and pain scores, and radiographic signs of implant stability. RESULTS: Ten European shorthair cats were included in the study. Pelvic floor fractures were stabilised using locking plates in nine cats, and symphyseal separation was fixated using hemicerclage wire in one cat. Additional procedures included reduction of sacroiliac luxation in nine cats with positional screws placed in six cats, and plate stabilization of sacral fractures in one cat. All cats were able to walk within five days of surgery. No orthopaedic or neurological deficits were observed in seven cats at follow-up. Neurological deficits were observed in one cat. Signs of pain at implant sites due to inadequate surgical technique were noted in two cats. Anatomical reduction of the pelvic floor was achieved in eight cats. CLINICAL SIGNIFICANCE: Stabilization of the pelvic floor and repair of sacroiliac luxation and other injuries by a ventral abdominal approach in cats led to an overall successful outcome. Fixation of the pelvic floor in cats with intact acetabular and ilial bones should be considered in patients with multiple pelvic fractures in combination with sacroiliac joint luxation or sacral fracture, pelvic canal narrowing, traumatic abdominal hernia, and other abdominal injuries.

Revision of an unstable HELICA endoprosthesis with a Zurich cementless total hip replacement.

A six-year-old, female, spayed Labrador Retriever was evaluated for progressive lameness of one year duration, ending in non-weight-bearing of the right hindlimb. The dog had a history of severe coxarthrosis of both hip joints, and had a HELICA hip prosthesis implanted in the right hip 18 months before. On survey radiographs, the acetabular and femoral components appeared unstable, with a large void in the proximal femur and a lacy periosteal reaction on the trochanter. Arthrocentesis was performed to rule out septic loosening. As culture samples were negative, the dog underwent surgery. We report the successful revision of an unstable HELICA screw hip prosthesis with a Zurich cementless total hip replacement. The patient had a good clinical and radiological outcome seven months postoperatively.

Repair of long-bone fractures in cats and small dogs with the Unilock mandible locking plate system.

OBJECTIVES: To retrospectively evaluate stabilisation of long-bone fractures in cats and small dogs using the Unilock system. METHODS: Medical histories and radiographs of consecutive patients with long-bone fractures stabilised with the Unilock system were reviewed. Cases with follow-up radiographs taken at least four weeks postoperatively were included. Signalment of the patient, fracture localisation and type, primary fracture repair or revision surgery, single or double plating, and complications for each patient were noted. Additionally, implant size, number of screws, number of cortices engaged with screws, and number of empty holes across the fracture were evaluated in fractures where a single plate had been applied. RESULTS: Eighteen humeral, 18 radial, 20 femoral, and 10 tibial fractures were treated. The Unilock system was used for primary repair in 44 fractures and for revision surgery in 22 fractures. Two plates were applied in 17 fractures, and a single plate was applied in 49 fractures. Follow-up radiographs were taken four to 109 weeks postoperatively. Complications were seen in 12 animals and 13 fractures (19.7%). Fixation failure occurred in seven fractures (10.6%). Cases with a single plate that suffered fixation failure had thinner screws in relation to bone diameter than cases with double plates, and more screws in a main fragment than those without fixation failure. CLINICAL SIGNIFICANCE: The Unilock system is a suitable implant for fracture fixation of long bones in cats and small dogs.

Longitudinal as well as age-matched assessments of bone changes in the mature ovariectomized rat model.

In the past, bone loss in the ovariectomized (OVX) osteoporotic rat model has been monitored using in vitro micro-computed tomography (micro-CT) to assess bone structure (bone volume/total volume, BV/TV). The purpose of this study was to assess the importance of baseline control and sham groups in 12-16-week-old, reproductively mature rats. Measurements were carried out in a longitudinal and age-matched fashion using newer in vivo peripheral quantitative computed tomography (pQCT), which measures apparent bone mineral density (BMD). BMD was measured at the distal femoral metaphysis of 12-week-old female Wistar rats with pQCT. Subsequently, animals were either OVX or sham operated, and pQCT measurements were repeated four weeks later. Then, all rats were euthanized and in vitro BMD and BV/TV were obtained by micro-CT imaging. Results from three consistently differentiated regions of interest showed that there was significant bone loss and growth during the four weeks in the OVX and sham group, respectively. Taking this into account, i.e. a posteriori superimposing growth to loss, no differences resulted between BMD values measured in a longitudinal fashion with pQCT and that measured in comparison with an age-matched sham group with micro-CT and pQCT. In addition, there was a strong linear correlation between BMD measured with pQCT and BV/TV obtained from micro-CT. In conclusion, this outcome provides new insights into individual bone changes due to OVX and growth in Wistar rats during the age period of 12-16 weeks, which is often applied in osteoporosis research as the 'mature' rat model. Data can be used as baseline information upon which future in vivo study designs with this rat model can refer to reduce and minimize animal use.

Effect of tibial tuberosity advancement on femorotibial shear in cranial cruciate-deficient stifles. An in vitro study.

OBJECTIVES: This in vitro study compares the femorotibial shear in canine stifles with intact and transected cranial cruciate ligaments (CrCL), before and after tibial tuberosity advancement (TTA) by measuring the distance between origin and insertion of the cruciate ligaments. METHODS: Radiodense markers were inserted into bones at the attachment sites of the cruciate ligaments in sixteen cadaveric stifles of adult dogs. Each stifle was then mounted in a testing apparatus. The distances between the markers were measured on mediolateral radiographs, performed on each stifle under three different situations: intact, after CrCL transection, and after performing a TTA. Stifles were loaded to create a constant tibiofemoral reaction force by maintaining the load parallel to the patellar ligament. Radiographs were taken in a preloaded and loaded state in the intact stifle and only in a loaded state after CrCL transection, and after performing a TTA. RESULTS: Loading the stifle joints after transection of the CrCL resulted in a mean lengthening of the CrCL marker distance of 22.4%. Loading the transected CrCL stifles after performing a TTA resulted in a mean shortening of the CrCL marker distance by 3.0% compared to the loaded intact condition. CLINICAL SIGNIFICANCE: This study demonstrates that, in loaded stifles with transected CrCLs, TTA causes a caudal shift in the cranial shear force, counteracting cranial subluxation of the tibia.

Joint mice migration into the deep digital flexor tendon sheath in dogs. Clinical cases and anatomical study.

This study describes the appearance of 'joint mice' in the sheath of the deep digital flexor muscle tendon (DDFT) due to osteochondritis dissecans (OCD) lesions in the talocrural joint of 12 dogs. Surgical excision of all free fragments in the DDFT sheath was performed in five dogs, and their clinical progression was documented. The excision of free fragments from the DDFT sheath, but not arthro-tomy, proved clinically beneficial despite the presence of degenerative joint disease. The anatomical communication between the talocrural joint and the DDFT sheath and its dimensions are further illustrated with the use of contrast media and dissection of cadaver limbs.

Temporary transarticular stabilization with a locking plate for medial shoulder luxation in a dog.

This report describes the temporary fixation of a traumatic shoulder luxation in a large-breed dog using a 3.5-mm Locking Round-Hole Reconstruction Plate (LRHRP) to provide stable internal splinting, allowing healing of the injured ligaments, joint capsule, glenohumeral ligaments, tendons, and muscles for restoration of joint stability. The use of a temporary plate with a locking system should be considered as an option in the treatment of canine shoulder joint luxations with severe tissue damage.

Force plate gait analysis to assess limb function after tibial tuberosity advancement in dogs with cranial cruciate ligament disease.

OBJECTIVE: To assess functional outcome in dogs with cranial cruciate ligament (CrCL) disease after tibial tuberosity advancement (TTA) using force plate gait analysis, and to evaluate parameters potentially influencing outcome. STUDY DESIGN: Prospective clinical study. ANIMALS: Consecutive clinical patients (n = 37) with CrCL-deficient stifles (n = 40). METHODS: The stifle joints were examined arthroscopically prior to TTA. Meniscal release was not performed if the medial meniscus was intact. Open medial arthrotomy and partial meniscectomy were performed in the presence of meniscal tears. Vertical ground reaction forces were measured preoperatively and at follow-up examinations four to 16 months postoperatively (mean: 5.9 months). The ground reaction forces of a group of 65 healthy dogs were used for the comparison. The potential effects of clinical parameters on functional outcome were evaluated statistically. RESULTS: Complete CrCL rupture was identified in 28 joints, and partial CrCL rupture in 12 joints. The medial meniscus was damaged in 21 stifles. Vertical ground reaction forces were significantly higher at follow-up (P < 0.01), but remained significantly lower than those of control dogs (P < 0.01). Complications were identified in 25% of joints, and the dogs with complications had significantly lower peak vertical forces at follow-up than the dogs without complications (P = 0.04). Other clinical parameters did not influence outcome. CONCLUSIONS: Tibial tuberosity advancement significantly improved limb function in dogs with CrCL disease, but did not result in complete return to function. Complications adversely affected functional outcome. CLINICAL SIGNIFICANCE: A return to a function of approximately 90% of normal can be expected in dogs with CrCL disease undergoing TTA.

Radiographic examination and outcome in consecutive feline trauma patients.

Using univariate analysis, the correlation between signalment, history, outcome and radiographic diagnosis made on whole-body radiographs was investigated in 100 consecutive feline trauma patients of an urban clinic. The radiographic findings included: 53 thoracic injuries, 39 abdominal injuries, 34 pelvic injuries, 28 soft tissue injuries, 26 spinal injuries, and 19 cases with signs of hypovolemia. Only four radiographs were considered normal. Surgical intervention was carried out in 51 cases. Of the 100 cases, 73 survived, 23 were euthanatized, and four died. A significant positive correlation with euthanasia was found when compared to patient age (p=0.0059), abdominal trauma (P=0.0500), spinal fractures (P=0.0468), and soft tissue injuries (P=0.0175). A significant negative correlation with survival was found when compared to patient age (P=0.0358), abdominal trauma (P=0.0439), intraperitoneal free air (P=0.0041), and soft tissue injury (P=0.0288). The results of this study indicate that whole-body radiographs are useful in detecting injury in the thorax, abdomen, spine, pelvis and soft tissues, and are valuable in the diagnostic work-up of feline trauma patients.

Force plate gait analysis at the walk and trot in dogs with low-grade hindlimb lameness.

OBJECTIVE: To evaluate the accuracy of force plate gait analysis at the walk and trot in dogs with low-grade hindlimb lameness. MATERIAL AND METHODS: Nineteen healthy dogs and 41 dogs with low-grade unilateral hindlimb lameness due to stifle or hip joint problems were walked and trotted over a force plate. Peak vertical forces (PVF) were recorded, and a symmetry index (SI) was calculated from the PVF of the hindlimbs. 'Cut-off' values were determined from the SI of the normal dogs. These cut-off values were used to discriminate lame dogs from normal ones. Sensitivity and specificity were evaluated for measurements at walk and trot, and the Cohen's Kappa coefficient (k) was used to determine the agreement between clinical lameness and force plate measurements, and between force plate results at walk and trot. Receiver Operating Characteristics (ROC) curve were plotted for both gaits to evaluate accuracy. RESULTS: The sensitivity of the measurements at walk was 0.63, and specifity was 0.95. The sensitivity of the measurements at trot was 0.90, and specificity was 1.0. Moderate agreement was found between force plate measurements at walk and trot, and between clinical gait assessment and force plate measurements at walk. Good agreement was found between clinical gait assessment and measurements at trot. ROC analyses revealed the trot (94.7% [91.7%; 97.7%]) to be the more accurate test than the walk (85.0% [80.1%; 89.9%]). CONCLUSION: The trotting gait was more sensitive and accurate than the walking gait for the differentiation of dogs with a low-grade hindlimb lameness from normal ones using force plate gait analysis.

Augmentation of the transverse acetabular ligament in canine caudoventral hip luxation.

Open surgical fixation was performed on four hip joints in three dogs who were suffering from caudoventral hip luxations for which closed reduction had previously failed. Stabilization of the joint was achieved with a ventral coxofemoral approach, which augmented the function of the transverse acetabular ligament using a sling implant through a bone tunnel (n = 1), a sling implant around two pelvic screws (n = 1), or an internal fixator plate (n = 2). Transverse acetabular ligament augmentation resulted in successful joint stabilization in all cases, and should be considered for the surgical reduction of caudoventral hip luxations in dogs. The use of an internal fixator plate, while preserving soft-tissue blood supply and resulting in minimal to no long-term arthritic changes, may provide an optimal outcome.

Chronic peritoneal effusion secondary to partial caudal vena cava obstruction following traumatic pneumothorax in a dog.

A three-year old, female Boxer Dog was treated initially with thoracocentesis for a right-sided pneumothorax. The dog was re-evaluated after three weeks because of an enlargement of the abdomen. A positive venogram revealed a ventral displacement of the caudal vena cava between the diaphragm and the heart, with a severe reduction of the diameter of the vein. An exploratory thoracotomy showed a displaced accessory lung lobe with an adhesion to the parietal pleura. Inflation of this lung lobe created a dynamic obstruction of the caudal vena cava, which resulted in ascites. Surgery offered successful treatment.

Use of the ComPact UniLock System for ventral stabilization procedures of the cervical spine: a retrospective study.

This study evaluates clinical application of the ComPact UniLock system for ventral stabilization of the cervical spine. Patient material included 13 consecutive cases, 12 dogs and one cat, with cervical spinal instabilities secondary to disc-associated wobbler syndrome (six dogs), traumatic, iatrogenic, and disc-associated cervical spinal instability of small dogs (four cases), cervical spinal fractures (one dog and one cat), and congenital atlantoaxial instability (one dog). The 2.0 system was used in smaller patients and the 2.4 system was applied in large dogs. Implant failure was observed on follow-up radiographs in one dog with a healed C2 fracture and screw pullout occurred in one dog with caudal cervical spondylomyelopathy, necessitating revision surgery. Implants remained stable throughout the follow-up period in the other cases. 'Good' or 'excellent' clinical outcome was achieved in 12 patients, including the dog with revision surgery. One dog had to be euthanatized due to postoperative deterioration of neurological status and development of pneumonia. The ComPact UniLock system was found to be a suitable implant for treating cervical instabilities of different origin in both small and large patients with lesions from C1/C2 to C6/C7. Some problems were encountered in the dogs with disc-associated Wobbler syndrome, such as lack or slow rate of vertebral fusion and partial collapse of the distracted intervertebral space on follow-up radiographs. A lack of adequate fusion was most likely related to grafting techniques used.

Long-term measurement of gastric motility using passive telemetry and effect of guar and cellulose as food additives in dogs.

The suitability of passive telemetry for long-term measurements of gastric motility in two groups of dogs with different body weights, four Beagles and four Labrador Retrievers, was investigated. An intra-abdominal measuring device, with a pressure sensor and electrodes within the gastric wall, allowed the continuous recording of the intensity and frequency of contractions simultaneously with an electromyogram (EMG). In fasting dogs a typical inter-digestive motility cycle was reproducible. Within 15 min of feeding the integral of the pressure curve increased significantly, reaching its maximum 30-45 min post-prandially. The peak frequency also significantly increased immediately after feeding, reaching the maximum of 22 contractions per 5 min. The post-prandial motility patterns of the groups were significantly different. The pressure amplitudes of the Labradors were significantly higher and the peak frequencies significantly lower than the Beagles. The addition of guar to the food (2.5% or 5%) leads to a significant reduction of the intensity of the antral contractions, whereas the frequency was hardly affected. In comparison, the effect of cellulose, as a food additive (2.5% or 5%), was rather modest. The intensity of the post-prandial contractions, influenced by cellulose, was significantly increased in Beagles, but was decreased in Labradors. Passive telemetry has been proven to be a suitable method for the long-term investigation of the physiological gastric motility and the effect of food additives. The measuring device was still functional after removal 8 weeks later.

Climatic conditions as a risk factor in canine gastric dilatation-volvulus.

Canine acute gastric dilatation-volvulus (GDV) is a life-threatening condition of multifactorial origin. The risk of developing GDV is influenced by a variety of factors, including breed, age, gender, temperament, diet and management. A relationship between seasonal variations and the frequency of GDV has been previously documented although no association was found with any specific climatic event. Variables in weather conditions within a defined geographic region were investigated in a retrospective study of 287 client-owned dogs diagnosed with GDV between 1992 and 1999. Monthly incidences were evaluated and differences in atmospheric temperature, humidity and pressure between days in which GDV cases were observed and days in which no case was presented were examined. Although temperature was significantly associated with the occurrence of GDV, the difference in temperatures between days with and days without GDV cases was so small that it is unlikely to be of clinical relevance. Moreover, no significant association was found between GDV occurrence and atmospheric pressure or humidity, and a seasonal variation in GDV incidence was not observed.