Do locking plugs improve implant strength? Biomechanical comparison of polyaxial locking constructs with and without locking plugs in a fracture gap model.

BACKGROUND: The objective of this study was to investigate the effects of locking plugs and the biomechanical properties of a 3.5 mm 8-hole polyaxial locking plate in a fracture gap model. Our hypothesis was that locking plugs would increase the strength and stiffness of the construct. Twelve 3.5 mm 8-hole plates were used to evaluate two different construct designs (with locking plugs vs. without locking plugs) with validated bone substitutes in a 25 mm bridging osteosynthesis gap model. Each construct was subjected to a single cycle four-point bending load to failure using a servo-hydraulic testing machine. Bending stiffness, bending strength, and bending structural stiffness were calculated and compared using an unpaired Student´s t-test. RESULTS: The plating construct with locking plugs did not show any significant increase in terms of bending stiffness, bending strength, and bending structural stiffness compared to plating construct without locking plugs in a 25 mm gap fracture model during a single cycle four-point bending. CONCLUSIONS: Under the conditions tested, filling empty plate holes with locking plugs in bridging osteosynthesis does not increase stiffness or strength of the plate-bone construct.

Partial laryngectomy for the management of laryngeal masses in six cats.

OBJECTIVES: Partial laryngectomy is an organ-sparing surgical procedure for the removal of laryngeal masses which has not been described in cats. The aim of this study was to report on the surgical procedure and the short- and long-term clinical outcomes of cats that underwent partial laryngectomy. METHODS: Medical records were retrospectively collected over a 4-year period in two institutions. The following data were retrieved: signalment, history, clinical signs, diagnostic test results, surgical procedure, postoperative management, complications and outcome. RESULTS: Six cats underwent partial laryngectomy. The most common clinical signs in cats with laryngeal masses were stridor (n = 4) and dyspnoea (n = 4). In all cats, a full-thickness portion of one or several laryngeal cartilages was resected, including thyroid cartilage alone (n = 2), thyroid cartilage and arytenoid (n = 2), and arytenoid cartilage and epiglottis (n = 2). The resected laryngeal masses were reported to be lymphoma (n = 3), carcinoma (n = 1), laryngeal cyst (n = 1) and inflammatory laryngeal disease (n = 1). All cats survived the surgical intervention of partial laryngectomy. Four cats showed varying degrees of respiratory distress in the short-term postoperative period. A temporary tracheostomy tube was placed in two cats. No other postoperative complications were noted in the short- or long-term. Four cats were still alive at the time of writing. These cats survived at least 252 days. CONCLUSIONS AND RELEVANCE: In a small number of cases, our results show that successful long-term outcomes after partial laryngectomy are achievable, with longer survival times than previously reported. Therefore, partial laryngectomy should be considered as a viable treatment option in cats with laryngeal masses.

Metabolic and hormonal responses to subcutaneous glucagon in healthy beagles.

OBJECTIVE: To compare the effects of subcutaneous (SC) and intravenous (IV) glucagon on glucose concentrations, and insulin and cortisol secretion. DESIGN: Prospective randomized 3-way crossover study. SETTING: University teaching hospital. ANIMALS: Five healthy beagles. INTERVENTIONS: Diabetes mellitus and adrenal insufficiency were excluded by repeated glucose and fructosamine measurements, urinalysis, abdominal ultrasonography, and ACTH stimulation tests. Blood samples were collected before and after the SC and IV injection of 1 milligram (1 mg = 1 mL) commercially available synthetic glucagon and analyzed for insulin-like immunoreactivity (insulin-imr), glucose, ACTH and cortisol concentrations. The results were compared with those obtained after the SC injection of 1 mL saline (placebo). Measurements were performed over a period of up to 3 hours. MEASUREMENTS AND MAIN RESULTS: SC glucagon significantly increased glucose and insulin-imr (P < 0.001 and 0.043, respectively). Peak glucose concentrations were observed after 20 minutes and were lower than after IV injection (mean ± SD: 6.5 ± 1.1 mmol/L versus 9.3 ± 0.8 mmol/L [117.1 ± 19.8 mg/dL versus 167.6 ± 14.4 mg/dL]; P = 0.001). The route of application had no significant effect on insulin-imr (peak concentration: median [range]: 83.3 [13.9-312.5] pmol/L versus 194.5 [118.1-284.7] pmol/L [12 [2-45] µU/mL versus 28 [17-41] µU/mL; P = 0.151). SC glucagon did not increase cortisol or ACTH concentrations at any time point of observation (P > 0.05). Aside from somnolence, no adverse events were recorded. CONCLUSIONS: SC glucagon has the potential to be used as a simple and safe test in diabetic animals, but is of little use in animals with suspected corticotrophic insufficiency. The hyperglycemic effects are significant, implying that the commercially available human emergency kit could be useful in the home treatment of canine hypoglycemic emergencies.

Thoracoscopic en bloc thoracic duct sealing and partial pericardectomy for the treatment of chylothorax in two cats.

Two cats with intractable idiopathic chylothorax and a history of unsuccessful medical management were treated thoracoscopically with en bloc thoracic duct sealing and subtotal pericardectomy using a bipolar feedback-controlled vessel sealing device. No surgical complications were observed. Twenty-four and 26 months after surgery, both cats were free of thoracic effusion and clinical signs.