Unilateral Uniplanar External Skeletal Fixation for Isolated Diaphyseal Tibial Fractures in Skeletally Immature Dogs

Objective: To report and evaluate use of external skeletal fixation (ESF) for repair of isolated (fibula intact) diaphyseal tibia fractures in skeletally immature dogs.
Study Design: Case series.
Animals: Skeletally immature (mean age, 17 weeks; range, 12–23 weeks) dogs (n=5) with isolated diaphyseal tibial fractures.
Methods: Medical records (2006–2007) of 5 dogs with isolated diaphyseal tibial fractures treated with Type 1a ESF were reviewed and outcome assessed by clinical examination and telephone interviews.
Results: Dogs were evaluated ∼2 and 4 weeks after surgery. Limb function, muscle mass, and comfort level remained very good to excellent throughout healing. Bony union was confirmed radiographically and the ESF removed ∼4 weeks after surgery (mean, 31.4 days; range, 28–37 days). Owner satisfaction was high when contacted a minimum of 4 weeks after ESF removal.
Conclusions: Use of Type Ia ESF with positive profile threaded pins is a practical and biologic method for treatment of isolated tibial fractures in skeletally immature dogs
Clinical Relevance: ESF is an effective alternative treatment to external coaptation and internal fixation for isolated diaphyseal tibial fractures in skeletally immature dogs.     

Radiographic Criteria for Evaluation of Uncemented Total Hip Replacement in Dogs

A zonal analysis system and corresponding nomenclature were developed to describe the location and nature of radiographic changes in canine uncemented total hip arthroplasties. Criteria to assess prosthetic component alignment, percentage of femoral canal fill, resorptive and formative bony changes, and alterations in the bone at the implant-bone interface were derived by studying serial radiographs of 100 consecutive canine uncemented total hip arthroplasties for up to 30 months after surgery.     

Clinical and Radiographic Evaluation of Intertrochanteric Osteotomy in Dogs: A Retrospective Study of 18 Dogs

Objective- To determine whether intertrochanteric osteotomy (ITO) can prevent the progression of degenerative joint disease (DJD) in dysplastic hip joints.
Study Design- The results of ITO were assessed retrospectively by using owner questionnaires, physical examination, and radiographic evaluation.
Animals- Eighteen client-owned dogs (29 coxofemoral joints were evaluated).
Methods- Lameness was scored according to a grading system. A scoring system was also developed to assess radiographically evident osteoarthritis on a ventrodorsal projection of the coxofemoral joints in extension.
Results- Twenty-nine ITO were performed in 18 dogs with varying degrees of hip dysplasia. The dogs were lame on 19 of 29 rear limbs on physical examination before surgery. In 22 of the 29 hip joints, palpation caused signs of pain. The median age at the first and second surgical procedure was 14.5 months and 18 months, respectively. Follow-up evaluation was performed on average at 9.77 (FU I), 22.52 (FU II), and 47.50 months (FU in) after surgery. Based on the owners' evaluation, there was a tendency toward improvement after surgery. The results of the physical examination at the preoperative examination and at the three follow-up examinations did not differ significantly. The follow-up radiographic scores showed significantly worse DJD than the preoperative scores.
Conclusions- ITO does not prevent progression of DJD in the dysplastic hip.
Clinical Relevance- Knowledge of the long-term effects of ITO is essential for surgeons trying to achieve improvement in dogs with hip dysplasia.     

The Effects of Beveling the Margins of Articular Cartilage Defects in Immature Dogs

Eight 4 month old crossbred puppies underwent surgery simulating treatment of osteochondritis dissecans. Both humeral heads were exposed by a caudal approach to the shoulder joint. In one, an 8 mm circular, full-thickness cartilage defect was created so that the remnant cartilage margin was perpendicular to the joint surface. In the other, a similar 8 mm defect was created with the chondral margins beveled at approximately 45 degrees. There was no clinical lameness in any of the dogs. At necropsy after 16 weeks, the cartilage defects with beveled edges were significantly larger (11.0 +/- 0.6 mm SD) than those with perpendicular edges (8.0 +/- 0.1 mm SD), because of the beveling (p = 0.0039). Fibrocartilage was present but did not always completely fill the defects. Articular surfaces of the glenoid cavities suffered erosion and fibrillation more frequently opposite beveled defects than opposite defects with vertical walls (p = 0.0312). This was presumably due to the larger apposing defect. It was concluded that the cartilage margins surrounding a chondral defect should not be beveled.     

Chemonucleolysis with Collagenase A Radiographic and Pathologic Study in Dogs

Collagenase, a proteolytic enzyme, was injected intradiscally in nine clinically normal, middle-aged beagles. Calcium chloride diluent solution (control), 100 ABC units of collagenase, and 250 ABC units of collagenase, were injected in randomly selected intervertebral discs (T13-L1 to L5-L6). On day 11, the discs injected with collagenase were narrowed radiographically, but there was no significant change in myelograms. Grossly and histologically, there was dissolution of the intervertebral discs, mainly nucleus pulposus, and protrusion of nucleus material in the vertebral body through bony end-plates in discs injected with collagenase. Collagenase chemonucleolysis may be an alternative to spinal surgery for intervertebral disc protrusion in dogs.     

Comparison of Computed Tomographic and Radiographic Popliteal Lymphangiography in Normal Dogs

Objective: To (1) describe computed tomographic (CT) popliteal lymphangiography; (2) compare the number of thoracic duct (TD) branches detected by CT and by radiography after popliteal lymphangiography; and (3) to compare the number of branches detected after left and right popliteal lymphangiography. Study Design: Experimental study. Animals: Adult dogs (n=6). Methods: A randomly selected popliteal lymph node was percutaneously injected with 12 mL iodinated contrast medium through a 25‐g butterfly catheter over 4–5 minutes. Lateral and ventrodorsal (VD) thoracic radiograph projections and thoracic CT were performed. The procedure was repeated using the contralateral lymph node after a 48–72 hours washout period. Results: One dog had TD branches visible on CT but not on radiographs. A significantly greater number of TD branches were observed with CT popliteal lymphangiography compared with lateral and VD radiographic popliteal lymphangiography (P=.003 and P<.001, respectively). The number of visible TD branches observed between the 6th thoracic and 1st lumbar vertebrae were not significantly different in these dogs (P=.146). A significant difference in number of TD branches observed was not found after left or right popliteal lymph node injection (P=.097). Conclusions: CT popliteal lymphangiography consistently identified a greater number of TD branches when compared with radiographic popliteal lymphangiography. Injection of either popliteal lymph node resulted in the same number of TD branches being observed.     

Determination of Proximal Femoral Epiphyseal Depth for Repair of Physeal Fractures in Immature Dogs

Objective—To determine the depth that implants may be safely placed for repair of proximal femoral physeal fractures.
Study Design—Relationships were determined between the depth of the proximal femoral epiphysis (PFE) and the contralateral PFE, and the PFE and pubic bone width.
Animals or Sample Population—20 immature dog cadavers.
Methods—Actual PFE depths were determined at the center of the physeal surface and at four other eccentric points. The contralateral intact PFE depth and the width of the cranial aspect of the pubic bone were measured from radiographs.
Results—Mean ratios of actual central PFE depth to radiographically measured (1) contralateral PFE depth and (2) pubic bone width were 1.04:1 and 1.09:1, and ratios of actual eccentric PFE depths were 0.89:1 and 0.93:1. Body weight was not useful in estimating depth of the PFE.
Conclusions —For the central epiphysis, pins may safely be placed a distance equal to 75% to 80% of the contralateral intact PFE depth or pubic bone width, measured from a ventrodorsal radiograph, with minimal risk of penetration through the articular surface. Pins placed eccentrically may be safely driven a depth equal to 65% of the radiographically measured contralateral intact PFE depth or pubic bone width.
Clinical Relevance —Estimating the safe depth of implant placement into the PFE avoids penetration of the articular surface.     

Neonatal Clinical Evaluation, Blood Gas and Radiographic Assessment After Normal Birth, Vaginal Dystocia or Caesarean Section in Dogs

This study aimed to standardize signs and diagnostic criteria of respiratory function in newborn puppies delivered normally or after dystocia and caesarean operation. A total of 48 neonates were allocated into groups: eutocia (n = 20), dystocia (n = 8), caesarean (c)-section (n = 20). Neonatal health was assessed using the Apgar score and body temperature was determined at 0, 5 and 60 min after delivery. Venous blood gases (pO₂ and SO₂) was measured immediately and 60 min after delivery, and a thoracic radiograph was made between 0 and 5 min of life. The c-section group had significantly lower Apgar scores at birth and 5 min. Hypothermia was present at 5 min in the eutocia and c-section groups, and at 60 min in all groups. The eutocia group had an irregular respiratory pattern in 78% of puppies at birth, 27.7% at 5 min and 21% at 60 min compared with 87.5%, 62.5% and 12.5% of the pups in the dystocia group where there was irregular respiratory rhythm, moderate to intense respiratory sounds with agonic episodes. The c-section group had respiratory alterations in 70%, 45% and 16% of puppies at 0, 5 and 60 min, respectively. Radiographic abnormalities were present in 17% of the pups in the eutocia group, 25% of the pups in the dystocia group and 30% of the pups in the c-section group, respectively. The c-section group had significantly lower SO₂ values at 60 min than at birth. All puppies had hypoxaemia, but a significant decrease was observed in the c-section group. Newborn puppies had tissue hypoxia and irregular respiratory pattern at birth. Caesarean-section puppies had lower vitality; however, all developed satisfactory Apgar scores at 5 min of life, regardless of the obstetric condition.     

Evaluation of Colistin in the Treatment of Respiratory Infections in Dogs

Thirty cases of respiratory infections in adult dogs were treated with colistimethate sodium. E. coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Paracolobactrum sp., and Aerobacter aerogenes responded to therapy, whereas Proteus sp., Streptococcus faecalis, Streptococcus pyogenes, and Staphylococcus aureus were resistant to treatment.     

Evaluation of Three Midazolam-Xylazine Mixtures Preliminary Trials in Dogs

The depressant effects of midazolam and xylazine on the central nervous system (CNS) were evaluated in 12 dogs. Xylazine was administered to six dogs (1.1 mg/kg intravenously [IV]) followed in 5 minutes by midazolam (1.0 mg/kg intramuscularly [IM]). In a second group of six dogs, xylazine (2.2 mg/kg IM) was followed in 5 minutes by midazolam (1.0 mg/kg IV). Both drug regimens induced rapid and profound sedation or anesthesia. Duration of action varied with the doses and routes of administration. Dogs given the high dose of xylazine IM had an arousal time of 95.4 +/- 8.9 minutes and a walking time of 155.4 +/- 8.8 minutes. These values exceeded the IV xylazine values threefold. Partial reversal of CNS depression was accomplished with either a benzodiazepine antagonist (flumazenil) or an alpha-2 antagonist (yohimbine). In a separate trial, a mixture of xylazine (0.55 mg/kg), midazolam (1.0 mg/kg), and butorphanol (0.1 mg/kg) with and without glycopyrrolate was evaluated in eight dogs. As with the xylazine-midazolam combinations, the CNS depressant effect of this mixture was clinically indistinguishable from anesthesia achieved with other rapid-acting injectable agents. Clinical signs of CNS depression were readily and completely antagonized by the simultaneous injection of flumazenil and yohimbine.     

Corneocyte Counts for Evaluation of Antiseborrheic Shampoos in Dogs

Abstract— An objective method for measuring corneocyte numbers before and after antiseborrheic shampoo therapy was assessed in dogs. Corneocytes were collected from six skin regions on the dorsal trunk of nine colony-raised beagles with clinically normal skin. Forty-eight collection sites were randomly assigned a treatment with one of seven medicated shampoos or water alone; six additional sites served as non-treated controls. Corneocytes were collected immediately before the first treatment, and 14 and 28 days after initiation of therapy with a 0.1% Tween 80 surfactant and a quantitative cup-scrub technique. Pretreatment corneocyte counts were not significantly different among the nine dogs nor among the randomly assigned treatment and control sites (3.55 · 10⁴ cells.cm^-2, SEM 0.17). Corneocyte counts increased in all treatment and control sites from days 0 to 14. Corneocyte counts were similar in the non-treated and water-treated sites from days 14 to 28. Corneocyte counts were not significantly different when the same treatments were compared on days 0, 14 and 28, or when different treatments were compared on the same day. The corneocyte collection technique used in this study proved to be a reliable method for assessing the rate of cell desquamation and cell surface cohesion in dogs.     

Pharmacokinetic and Phase I Evaluation of Carboplatin in Dogs

Thirty dogs with spontaneously occurring malignant neoplasms were treated monthly with carboplatin (CBDCA) given as a 30-minute intravenous infusion in a dose escalation study. Twenty-eight dogs were considered evaluable for toxicity. The maximally tolerated dose of CBDCA was conceptually defined as that dose, determined by logistic regression analyses of toxicity data, resulting in a 50% incidence of moderate toxicity (MOD₅₀) or a 5% incidence of severe toxicity (SEV₅). Each designated maximally tolerated dose was calculated for the first course of treatment only and for the first and second courses of treatment combined to estimate cumulative drug toxicity. The MOD₅₀ and SEV₅ for the first treatment course were 340 and 278 mg/M², respectively. MOD₅₀ and SEV₅ values for the first plus second treatment courses were 327 and 231 mg/M², respectively. The nadir of neutrophil and platelet counts occurred approximately 14 days after treatment. The mean neutrophil and platelet values for all dogs experiencing myelosuppression during the first two treatment courses were 1541/μL and 62,600/μL, respectively. Nonparametric pharmacokinetic analysis of plasma CBDCA values suggested that half-life (T_1/2), area-under-the-curve and total body clearance (CL_b) were not dose dependent. Volume of distribution (VD_ss) significantly increased with dose only between 100 and 150 mg/M², not between 150 and 300 mg/M². Dose-independent serum CBDCA pharmacokinetic disposition indicates that detailed investigation of tissue CBDCA distribution would be warranted and may identify novel dosing strategies that could improve the therapeutic index of CBDCA by minimizing toxicity. (Journal of Veterinary Internal Medicine 1993; 7:235–240. Copyright © 1993 by the American College of Veterinary Internal Medicine.)     

Evaluation of Polysulfated Glycosaminoglycan for the Treatment of Hip Dysplasia in Dogs

A double-blinded, controlled clinical study was performed to compare the response of adult dogs affected with hip dysplasia to a placebo and three different dosages of polysulfated glycosaminoglycan (PSGAG): 2.2 mg/kg, 4.4 mg/kg, and 8.8 mg/kg. Dogs were randomly assigned to treatment groups. The drug was administered intramuscularly every 3 to 5 days for a total of eight injections. Response to treatment was analyzed based on changes in lameness, range of motion (ROM), and pain on manipulation of the hip joints. Evaluation for adverse reactions included complete blood cell (CBC) count, blood urea nitrogen (BUN), creatinine, and physical examination. Data were collected on a total of 111 dogs. Eighty-four met all criteria for inclusion in the study. Dogs that were given 4.4 mg/kg of PSGAG showed the greatest improvement in orthopedic scores, whereas dogs in the placebo group showed the smallest improvement; however, the differences in clinical improvement between the four treatment groups were not statistically significant. No local or systemic adverse reactions related to the drug were observed.     

Clinical and Radiographic Evaluation of a Median Sternotomy Technique in the Dog

This study evaluated postoperative sequelae following a sternotomy closed with transsternal and parasternal sutures in nine dogs. Wound complications noted within 30 days suggested excessive intraoperative trauma to bone or surrounding soft tissues. Radiographic evaluation at the end of this period demonstrated a significant lack of osseous bridging between the sternal halves in eight of nine dogs. There was frequent wire breakage, suggesting instability of the sternal halves and considerable midline inaccuracy when splitting the sternum. Postoperative pain was minimal. This technique is suitable for use in dogs provided that swaged-on needles and sufficient transsternal wires are used, the sternebrae are carefully split on the midline, and the wires are carefully twisted to assure a tight closure.     

三种麻醉诱导方法对杂种犬吸入麻醉的影响

为评价3种麻醉诱导方法在吸入麻醉中对试验犬麻醉效果的影响。本试验将15只杂种犬,分为A、B、C 3组,每组5只。A组为盐酸氯胺酮、速眠新Ⅱ组,B组为戊巴比妥钠组,C组为盐酸氯胺酮、地西泮注射液组,各组在诱导麻醉后行气管插管,应用异氟烷进行吸入麻醉,在不同时间点对试验犬的心率(HR)、血压(BP)、血氧饱和度(SPO2)、体温(TPR)、心电(ECG)进行监测,监测各时间点参数应用SPSS13.0软件进行统计并与A组数据相比较。试验结果表明,B、C两组与A组在麻醉后的心率、诱导5 min后的血氧、试验犬诱导期差异显著P<0.05,A组麻醉诱导剂对试验犬存在心率抑制作用,部分试验犬出现心电延迟;3组试验犬诱导期为B相似文献