Clinical findings for dogs undergoing elective and nonelective cholecystectomies for gall bladder mucoceles.

OBJECTIVES: The purpose of this study was to describe elective and nonelective post-cholecystectomy complications and mortality rates in dogs with a gall bladder mucocele. The secondary purpose was to report complications and mortality rates for different methods of common bile duct catheterisation. MATERIALS AND METHODS: A multi-institutional retrospective case series was performed to identify dogs with a gall bladder mucocele between 2004 and 2018 that underwent a cholecystectomy. Dogs were classified into nonelective or elective based on the presence or absence, respectively, of gall bladder rupture, biliary duct distension, clinical signs or hyperbilirubinemia. Each cholecystectomy was classified into three groups: duodenotomy and retrograde catheterisation, normograde catheterisation or no catheterisation. Complications were divided into four grades based on increasing severity and mortality rates were assessed for each. RESULTS: The mortality rate was 2 (6%) out of 31 for dogs undergoing an elective cholecystectomy and 21 (23%) out of 90 for dogs undergoing a nonelective cholecystectomy. The complication rate was 52% for the elective cholecystectomy and 50% for nonelective cholecystectomy. The majority of the complications in the elective category were grade 1 (mild). Post-operative hyperthermia developed in 35% of dogs that had a duodenotomy and retrograde common bile duct catheterisation, in 4% of dogs with a normograde common bile duct catheterisation and in 7% of dogs that did not have the common bile duct catheterised. CLINICAL SIGNIFICANCE: Elective cholecystectomy in dogs with a gall bladder mucocele in this study carried a low mortality rate and a relatively high frequency of minor complications.

Effect of oral administration of carprofen on intraocular pressure in normal dogs.

The aim of this study was to determine the effect of oral administration of carprofen on intraocular pressure in normal dogs. Twelve young adult beagle dogs were randomly assigned to treatment (n = 6) or control (n = 6) groups. After an 11-day acclimation period, the treatment group received approximately 2.2 mg/kg carprofen per os every 12 h for 7 days, and the control group received a placebo gel capsule containing no drug per os every 12 h for 7 days. Intraocular pressure (IOP) was measured by a rebound tonometer at three time points per day (8 am, 2 pm, and 8 pm) during the acclimation (days 1-11) and treatment (days 12-18) phases and for 48 h (days 19-20) after the completion of treatment. There was no statistically significant change in IOP for either eye in the dogs receiving oral carprofen during the treatment phase (days 12-18). After day 4, no significant daily IOP changes were seen in control group dogs. Carprofen administered orally every 12 h for 7 days had no effect on IOP in normal beagle dogs. An acclimation period to frequent IOP measurements of at least 5 days is necessary to establish baseline IOP values and minimize possible anxiety-related effects on IOP measurements.

Comparison of four commercial devices to measure limb circumference in dogs.

We evaluated four measurement devices for obtaining circumferential measurements at four locations on the canine hindlimb and forelimb. We hypothesised that these devices would be consistent and precise in the hands of veterinary professionals with varying experience levels. Circumferential measurements were made in five dogs with no history or clinical evidence of orthopaedic disease. Measurements were obtained in triplicate by three observers at mid-thigh, tibial tuberosity, hock and carpus bilaterally. Results indicated a significantly larger measurement at the left mid-thigh region than the right, with no significant differences between limbs noted at other sites. Measurements with a tape measure and a retractable tape measure resulted in significantly smaller values at each site than an ergonomic measuring tape and a circumference measuring tape. Interobserver variation was 3.6 times higher than intraobserver variation. These results illustrate the importance of consistency when obtaining these measurements. Sequential circumference measurements should be made by the same individual using the same device to decrease measurement variability. Devices were equally precise for repeat measurements although the absolute measurement varied by device.

Effect of bandaging on post-operative swelling after tibial plateau levelling osteotomy.

OBJECTIVE: To compare the effects of bandaging on immediate postoperative swelling using a modified Robert-Jones bandage after tibial plateau levelling osteotomy (TPLO) in dogs. STUDY DESIGN: Prospective case series. METHODS: Dogs undergoing a TPLO were randomly placed into two groups. Group 1 received a modified Robert-Jones bandage postoperatively for a 24 hour period and Group 2 was not bandaged. Hindlimb circumference was measured at the level of the mid-patella, the distal aspect of the tibial crest, the mid-point of the tibial diaphysis and the hock. Measurements were recorded and compared in each group preoperatively and at 24 hours and 48 hours post-operatively. Interobserver variability was compared between the two observers. RESULTS: There was no significant difference in postoperative swelling, as measured by the percentage change in circumference, between bandaged and unbandaged operated limbs after the TPLO at 24 and 48 hours at any site. Some significant differences in measurement at particular sites were observed between the two different observers, but there was a significant linear correlation at all sites between observers. The observer with the least experience consistently had slightly higher measurements at these sites. CLINICAL RELEVANCE: The use of a modified Robert-Jones bandage after TPLO did not prevent statistically significant postoperative swelling, and thus may not be indicated for this purpose. Postoperative bandages placed to control swelling after other small animal orthopaedic procedures should be evaluated individually for efficacy.

Ground reaction force analysis of unilateral coxofemoral denervation for the treatment of canine hip dysplasia.

Coxofemoral denervation has success rates of 90-96% reported retrospectively for palliative treatment of hip dysplasia. The aim of this study was to objectively evaluate ground reaction forces (GRF) in dysplastic dogs after unilateral denervation. Unilateral coxofemoral denervation was performed by means of a previously reported technique on 10 dogs with asymmetric gait. GRF were measured at zero, one and three months. Statistical analysis was performed using repeated measures analysis of variance and paired t-tests, with p< or =0.05. There was a lack of significant difference in mean peak vertical force (PVF) or vertical impulse (VI) in the operated limb (TX) over time. For the unoperated limb (UnTX), mean PVF and VI significantly decreased over time. The dogs were significantly more lame in the TX limb initially and at one month, however, there was no significant difference between limbs by three months. In the UnTX limb, 40% of dogs decreased PVF by >5%, by three months. Over time, there was no significant difference in mean average rise or mean average fall for TX or UnTX limbs. Between limbs, mean rise in the TX limb was significantly less at zero months, but not at one or three months. Decreased compensatory load shifting to the UnTX limb due to procedural efficacy could explain decreases in the UnTX limb. Worsening disease could also explain decreases in the UnTX limb, and may indicate a protective effect denoted by a lack of change in the TX limb. Longer follow-up would be required in improved dogs in order to document continued efficacy.

Digital measurement of radiographic tibial plateau angle. A comparison to measurement on printed digital images.

Pre-operative digital radiographs from 50 dogs undergoing a tibial plateau leveling osteotomy were evaluated. Tibial plateau angles were measured directly on printed films and measured on digital images using two different commercial DICOM viewers. The radiographs were scored for osteoarthritis and positioning. Using pooled results, the mean TPA from the digital images employing Web1000 (26.47 degrees +/- 3.90) was significantly higher then the mean TPA using film radiographs (25.41 degrees +/- 3.51), or IQ-View Pro (25.48 degrees +/- 3.89). There was not a significant difference between mean TPA using radiographs or IQ-view. Digital TPA measurement using built-in angle calipers in the clinical setting is a valid technique compared to measurements from film radiographs, and produces reproducible results. However, before changing to digital measurements, the chosen software programme should be validated against measurements using film radiographs to determine the magnitude of differences.

Matrix metalloproteinase and tissue inhibitor of metalloproteinase in serum and synovial fluid of osteoarthritic dogs.

To better understand the mechanisms responsible for the pathological processes of osteoarthritis (OA) and to potentially identify a profile of changes that could be predictive of early OA, matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) in the synovial fluid and serum of normal and osteoarthritic dogs were examined. The concentration of MMP-1 in the synovial fluid of osteoarthritic dogs (0.62 +/- 0.16), as measured by densitometry, was significantly higher than that found in control dogs (0.42 +/- 0.19) (P = 0.03). The concentration of MMP-1 in the serum of osteoarthritic dogs (0.74 +/- 0.16) was significantly less than that found in control dogs (0.87 +/- 0.08) (P = 0.05). The concentration of TIMP-2 in the synovial fluid of osteoarthritic dogs (46.2 +/- 21.9 ng/ml) was significantly less than that of control dogs (122.0 +/- 66.5 ng/ml) (P = 0.009). The concentration of TIMP-2 in the serum of osteoarthritic dogs (116.2 +/- 43.1 ng/ml) was not significantly different than that of control dogs (95.1 +/- 94.4 ng/ml) (P = 0.554). In addition, a phospho-tyrosine immunoprecipitation and mass spectrometry were used to isolate and identify interferon-alpha in canine synovial fluid.

A comparison of palpation guided and ultrasound guided percutaneous biceps brachii tenotomy in dogs.

The purpose of this study was to compare palpation guided and ultrasound guided techniques for biceps brachii tenotomy in dogs. The differences between the two tenotomy procedures in muscle incision length, confidence level of tenotomy, percentage tendon transection, difficulty of tendon location or transection, or amount of haemorrhage, were not significant. The ultrasound guided tenotomy procedure took significantly longer to perform and required a longer skin incision, but these differences were not considered to be clinically important. With palpation guided tenotomy, several surrounding muscular and tendinous structures were damaged. We concluded that ultrasound guided tenotomy is an accurate method of tendon identification because it allowed for complete transection in 10 out of 11 tendons, and provides a method for checking completeness of tendon transection after the procedure.

Evaluation of healing in feline femoral defects filled with cancellous autograft, cancellous allograft or Bioglass.

Cancellous bone grafting is a widely accepted technique in human and veterinary orthopaedic surgery. However, the use of autogenous bone graft is limited by the additional surgical time required to harvest the graft, the morbidity associated with the donor site, and the limited availability of cancellous bone, especially in feline patients. Various allografts and bone graft substitutes are available commercially but have not been fully evaluated for efficacy in the cat. The purpose of this study was to compare the incorporation of autogenous and allogenous cancellous bone graft and Bioglass, a synthetic bone graft substitute, in femoral defects in cats. Four (4.0 mm diameter) defects were created in the lateral diaphyseal cortex of the left femur with an orthopaedic drill. In each femur, one of the cortical defects was filled with autogenous cancellous graft (harvested from the tibia), one was filled with allogenic cancellous graft, and one was filled with Bioglass. The fourth defect remained unfilled. Graft incorporation within the femoral defects was evaluated by radiographic evaluation every two weeks. Six weeks after the grafting procedure, the cats were euthanatized and high detailed radiography, dual energy X-ray absorptiometry (DEXA), histopathology and histomorphometry of the defects were performed. Satisfactory bone healing was observed within all of the defects.

Multilobular tumour of bone with no abnormalities on plain radiography in a dog.

A seven-year-old neutered female golden retriever was presented for an acute onset of cervical pain and ataxia. Intervertebral disc disease or neoplasia was suspected. There was no evidence of a soft tissue or bony mass on physical examination or survey radiographs. Cerebrospinal fluid analysis did not show any evidence of a neoplastic process. Myelographic evaluation identified an extradural mass lesion extending from inside the calvarium to the mid-body of the first cervical vertebra. No additional diagnostic tests were performed as the owners elected for euthanasia because of the high possibility of a neoplastic process with an accompanying poor prognosis. Multilobular tumour of bone was diagnosed on postmortem examination.

Hind limb lameness in the mature dog.

This article describes the differential diagnosis of hind limb lameness in adult dogs with common clinical presentations and diagnostic methods outlined.

Hepatotoxicity of stanozolol in cats.

OBJECTIVE: To determine hepatotoxicity of stanozolol in cats and to identify clinicopathologic and histopathologic abnormalities in cats with stanozolol-induced hepatotoxicosis. DESIGN: Clinical trial and case series. ANIMALS: 12 healthy cats, 6 cats with chronic renal failure, and 3 cats with gingivitis and stomatitis. PROCEDURES: Healthy cats and cats with renal failure were treated with stanozolol (25 mg, i.m., on the first day, then 2 mg, p.o., q 12 h) for 4 weeks. Cats with gingivitis were treated with stanozolol at a dosage of 1 mg, p.o., every 24 hours. RESULTS: Most healthy cats and cats with renal failure developed marked inappetence, groomed less, and were less active within 7 to 10 days after initiation of stanozolol administration. Serum alanine transaminase (ALT) activity was significantly increased in 14 of 18 cats after stanozolol administration, but serum alkaline phosphatase activity was mildly increased in only 3. Four cats with serum ALT activity > 1,000 U/L after only 2 weeks of stanozolol administration had coagulopathies; administration of vitamin K resolved the coagulopathy in 3 of the 4 within 48 hours. All 18 cats survived, and hepatic enzyme activities were normal in all cats tested more than 4 weeks after stanozolol administration was discontinued. Two of the 3 cats with gingivitis developed evidence of severe hepatic failure 2 to 3 months after initiation of stanozolol treatment; both cats developed coagulopathies. Histologic evaluation of hepatic biopsy specimens from 5 cats revealed diffuse hepatic lipidosis and cholestasis without evidence of hepatocellular necrosis. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that stanozolol is hepatotoxic in cats.

Asymmetric adaptive modeling of central tarsal bones in racing greyhounds.

Fatigue fracture of the cuboidal bones of the foot, especially the navicular tarsal bone, is common in athletes and dancers. The racing greyhound is a naturally occurring animal model of this injury because both microcracking and complete fracture occur in the right central (navicular) tarsal bone (CTB). The right limb is on the outside when racing in a counter-clockwise direction on circular tracks, and is subjected to asymmetric cyclic compressive loading. We wished to study in more detail adaptive modeling in the right CTB in racing greyhounds. We hypothesized that cyclic asymmetric loading of a cuboidal bone induced by racing on a circular track would induce site-specific bone adaptation. We also hypothesized that such an adaptive response would be attenuated in greyhounds that were retired from racing and no longer subjected to cyclic asymmetric loading. Central tarsal bones from racing greyhounds (racing group, n = 6) and retired greyhounds being used for breeding (nonracing group, n = 4) were examined using quantitative computed tomography (CT). Bone mineral density (BMD) was determined in a 3-mm diameter region-of-interest (ROI) in six contiguous 1-mm-thick sagittal CT slices of each CTB. Bones were subsequently examined histomorphometrically and percentage bone area (B.Ar./T.Ar., %) was determined in 10 ROI from dorsal to plantar in a transverse plane, mid-way between the proximal and distal articular surfaces. The BMD of the right CTB was greater than the left in all greyhounds (p < 0. 001). In comparing ipsilateral limbs between groups, BMD of the racing group was greater than the nonracing group for each side (p < 0.005). In sagittal plane histologic sections, bone in the dorsal region of the right CTB had undergone adaptive modeling, through thickening and compaction of trabeculae. B.Ar./T.Ar., % in the right CTB of the racing group was greater than in the contralateral CTB (p < 0.001), and the ipsilateral CTB of the nonracing group (p < 0.001). In the nonracing group, B.Ar./T.Ar., % in the right CTB was not significantly different from left CTB (p > 0.8; power = 80% at Delta = 48%). It was concluded that greyhounds racing on circular tracks develop site-specific bone adaptation with compaction of trabecular bone and increase in BMD in the right CTB in particular, the most common site for fatigue fracture. Our data also suggested that partial reversal of this adaptive process occurred in retired, nonracing greyhounds, after cessation of asymmetric cyclic loading at racing speed. Racing greyhounds provide a model in which to study fatigue fracture and adaptation of cuboidal foot bones subjected to cyclic loading.

Bone plate fixation of distal radius and ulna fractures in small- and miniature-breed dogs.

Bone plate fixation was reviewed in 29 distal radial fractures of small- and miniature-breed dogs. Twenty-two fractures in 18 dogs were available for follow-up. Number of complications and return to function were evaluated. Complications occurred in 54% of the fractures. Catastrophic complications occurred in 18% of fracture repairs with follow-up, while minor complications occurred in 36%. Sixteen (89%) of 18 dogs had a successful return to function. Bone plate fixation is a successful repair method for distal radius and ulna fractures in small-breed dogs, compared to previously reported methods.

Scintigraphic evaluation of dogs with acute synovitis after treatment with glucosamine hydrochloride and chondroitin sulfate.

OBJECTIVE: To evaluate the effects of orally administered glucosamine hydrochloride (GlAm)-chondroitin sulfate (CS) and GlAm-CS-S-adenosyl-L-methionine (SAMe) on chemically induced synovitis in the radiocarpal joint of dogs. ANIMALS: 32 adult mixed-breed dogs. PROCEDURE: For 21 days, all dogs received a sham capsule (3 groups) or GlAm-CS (prior treatment group) in a double-blinded study. Unilateral carpal synovitis was induced by injecting the right radiocarpal joint with chymopapain and the left radiocarpal joint (control joint) with saline (0.9% NaCl) solution. Joints were injected on alternate days for 3 injections. After induction of synovitis, 2 groups receiving sham treatment were given GlAm-CS or GlAm-CS-SAMe. Another group continued to receive sham capsules (control group). Joint inflammation was quantified, using nuclear scintigraphy, before injection of joints and days 13, 20, 27, 34, 41, and 48 after injection. Lameness evaluations were performed daily. RESULTS: Dogs given GlAm-CS before induction of synovitis had significantly less scintigraphic activity in the soft-tissue phase 48 days after joint injection, significantly less uptake in the bone phase 41 and 48 days after joint injection, and significantly lower lameness scores on days 12 to 19, 23, and 24 after injection, compared with other groups. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of results of this study suggest that prior treatment with GlAm-CS for 21 days had a protective effect against chemically induced synovitis and associated bone remodeling. Prior treatment with GlAm-CS also reduced lameness in dogs with induced synovitis.

Nonselection and nonresponse bias in clinical research.

In summary, nonselection and nonresponse bias can have a potent impact on the validity of clinical veterinary research studies and should be carefully assessed by investigators and readers. The risk of nonselection and nonresponse bias has been compared to "lowering yourself into a dark pit and trusting you won't be bitten by a snake ... before you go into the pit, you should stand outside and listen for a hissing sound ... if you hear one, do not go on ... if you do not hear anything, you may proceed with caution, being confident that at worst you will be bitten by a quiet snake."

Development of interactive patient-based multimedia computer programs in veterinary orthopedic radiology.

Three computerized multimedia programs on large and small animal veterinary orthopedic radiology were developed and implemented for the radiology curriculum as an alternative to traditional film-based laboratory learning. Programs utilized "hot words" (colored text words that displayed an overlaid image label that highlighted lesions) and interactive quizzes which responded appropriately to selected answers. "Hot words" helped students develop confidence in accurate lesion detection and the interactive quizzes transformed learning from a passive to an active process. Multiple examples were provided for reinforcement and concepts were incorporated from other clinical disciplines for curriculum integration. Programs were written using a presentation software program, Toolbook for DOS based platform, and contained radiographic images made by laser-scanning digitization. Multiple students could simultaneously access the programs through a network server. These pilot programs were implemented successfully and computerized multimedia presentation proved to be well suited to teaching radiology. Development of the programs required attention to a number of hardware, software, time and cost factors.

Scintigraphic assessment of distal extremity perfusion in 17 patients.

To assess the role of scintigraphic evaluation of distal limb perfusion, the medical records and scintigraphic perfusion images of 17 animals (8 dogs, 2 cats, 2 calves, 4 birds and 1 ferret) with clinical signs of distal limb ischemia were examined retrospectively. Images were obtained at 5 and 10 minutes following injection of 99mTc-MDP, or 99mTc-DTPA. The initial scintigraphic diagnoses of 17 animals included complete ischemia (8/17), partially reduced perfusion (5/17), and normal to increased perfusion (4/17). In 4 of the animals with partially reduced perfusion, follow-up scans indicated progression to complete ischemia (1/4) or normal to increased perfusion (3/4). Nine of 17 animals had a final scintigraphic diagnosis of complete distal limb ischemia, and these animals were either euthanized (5/9) or had limb amputation (4/9). A final diagnosis of complete ischemia was supported with either repeat scanning (3/10), continued clinical observation (6/10) and/or pathological examination (10/10). Clinical signs of ischemia resolved in all (7/17) animals with increased or normal perfusion on their final scan. Scintigraphy provided a safe and noninvasive assessment of distal limb perfusion, which corresponded with clinical outcome.

Improved osseointeraction of calcium phosphate-coated external fixation pins. Studies in calves.

We investigated osseointeraction of solution-precipitated calcium phosphate (SPCP)-coated transfixation pins used in external skeletal fixation of a calf stable fracture model. One group (SPCP) received centrally-threaded transfixation pins which had SPCP coating; the other group (control) received identical, but not coated, pins. Radiographs were obtained 1 and 40 days after surgery and examined for evidence of osteolysis. Bone phase 99mTc-MDP studies were performed 6 and 28 days after surgery. Calves were killed 40 days after surgery and mechanical tests performed. Dual-energy x-ray absorptiometry (DEXA) and histomorphometric analyses were done. A smaller proportion of SPCP pins (5/24) had evidence of discharge during the study compared with control pins (21/24). A smaller proportion of SPCP pins (4%) had radiographic evidence of osteolysis compared with control pins (42%). Uptake of 99mTc-MDP was similar for SPCP and control calves. Uptake was significantly greater in bone segments showing radiographic evidence of osteolysis than in bone segments not having osteolysis. Yield stress (MPa) for axial displacement was similar in the treatment groups. Bone mineral density was less in SPCP pins. Affinity index and interface histologic score were greater and osteoclastic index less in SPCP calves. Coating of transfixation pins with solution-precipitated calcium phosphate improved the osseointeraction of pin and bone during this 40-day study.