Robert S. Gilley

Incidence of and risk factors for postoperative pneumonia in dogs anesthetized for diagnosis or treatment of intervertebral disk disease

OBJECTIVE To determine incidence of and risk factors for postoperative pneumonia in dogs anesthetized for diagnosis or treatment of intervertebral disk disease (IVDD). DESIGN Retrospective case-control study. ANIMALS 707 dogs that underwent general anesthesia for the diagnosis or treatment of IVDD between 1992 and 1996 or between 2002 and 2006. PROCEDURES Postoperative pneumonia was diagnosed if compatible clinical signs (cough or hypoxemia) and radiographic abnormalities (alveolar infiltrates) developed within 48 hours after anesthesia. To identify risk factors for postoperative pneumonia, findings for dogs that developed postoperative pneumonia between 2002 and 2006 were compared with findings for a randomly selected control group of unaffected dogs from the same population. RESULTS There were no significant differences in age, breed, body weight, sex, location of IVDD, or survival rate between the 2 time periods, but there were significant differences in the use of magnetic resonance imaging, computed tomography, and hemilaminectomy and in the percentage of dogs that developed postoperative pneumonia in the later (4.6%) versus the earlier (0.6%) years. Significant risk factors for postoperative pneumonia included preanesthetic tetraparesis, cervical lesions, undergoing magnetic resonance imaging, undergoing > 1 anesthetic procedure, longer duration of anesthesia, and postanesthetic vomiting or regurgitation. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that at this institution, the incidence of postoperative pneumonia in dogs anesthetized for diagnosis or treatment of IVDD had increased in recent years.

Mandibular reconstruction after gunshot trauma in a dog by use of recombinant human bone morphogenetic protein-2

CASE DESCRIPTION A 6-year-old German Shorthaired Pointer was evaluated for possible reconstruction of a mandibular defect resulting from gunshot trauma. CLINICAL FINDINGS A 5-cm defect of the right mandibular body was evident. A segment of the mandibular body was removed 9 weeks earlier because of severe contamination and comminution associated with gunshot trauma. Subsequent right-sided mandibular drift resulted in malocclusion in which the left mandibular canine tooth caused trauma to mucosa of the hard palate medial to the left maxillary canine tooth. The right maxillary canine tooth caused trauma to gingiva lingual to the right mandibular canine tooth. TREATMENT AND OUTCOME The right mandible was stabilized with a 2.0-mm maxillofacial miniplate positioned along the lateral alveolar margin and a 2.4-mm locking mandibular reconstruction plate placed along the ventrolateral mandible. An absorbable compression-resistant matrix containing collagen, hydroxyapatite, and tricalcium phosphate was soaked in recombinant human bone morphogenetic protein-2 (rhBMP-2; 7.2 mL of a 0.5 mg/mL solution for a dose of 3.6 mg) and placed in the defect. By 4 weeks after surgery, an exuberant callus was evident at the site of the defect. By 7 months after surgery, the callus had remodeled, resulting in normal appearance, normal occlusion, and excellent function of the jaw. CLINICAL RELEVANCE Mandibular defects resulting from gunshot trauma can be treated by removal of contaminated tissue and comminuted bone fragments, followed by staged reconstruction. The combination of rhBMP-2 and compression-resistant matrix was effective in a staged mandibular reconstruction in a dog with a severe traumatic mandibular defect.

Surgical Stabilization of an Occipitoatlantoaxial Malformation in an Adult Dog

OBJECTIVE To report surgical planning, technique, and outcome of stabilization surgery in an adult dog with occipitoatlantoaxial malformation (OAAM). STUDY DESIGN Clinical report. ANIMAL A 19-month-old, 25.5 kg, male castrated, Shiba Inu. METHODS Radiographic and magnetic resonance imaging were used to identify and characterize OAAM. Using a ventral approach to the cranial cervical region 2 cortical bone screws were inserted from the axis into the malformed atlas and occiput. RESULTS Ambulation was conserved postoperatively. Within 4 weeks, neurologic examination was mostly normal except for decreased proprioception in the right pelvic limb. At 9 months, the dog retained an extended neck posture, but had no neurologic abnormalities. CONCLUSION OAAM should be considered as a differential diagnosis in an adult dog with cervical myelopathy. Surgical fixation with cortical bone screws using a ventral approach can be successful.

External fixator clamp reuse degrades clamp mechanical performance.

OBJECTIVE To determine the effects of clamp reuse for the Kirschner-Ehmer (KE); Securos; and the IMEX-SK clamp. STUDY DESIGN Experimental bench test of mechanical properties. METHODS Specially designed fixtures were used to mechanically test 18 clamps of each type with respect to 6 mechanical variables: fixator pin slippage, connecting bar slippage, fixator pin rotation, connecting bar rotation, and clockwise and counterclockwise clamp-bolt axis pivot. Each clamp was tested 6 times for each variable at 7.68 Nm of clamp-bolt tightening torque. RESULTS were compared using repeated measures ANOVA. Results- For the IMEX-SK clamp, a significant degradation in the force required to cause slippage was found for connecting bar slippage and fixator pin rotation; however, this clamp also had a significant increase in the force to initiate slippage for clockwise clamp-bolt axis pivot with reuse. The Securos clamp had significant degradation in connecting bar slippage, connecting bar rotation, and fixator pin rotation whereas the KE clamp had significant degradation in connecting bar slippage only. CONCLUSIONS All 3 external fixator clamp types degraded in 1 or more movement variables in their ability to resist motion with reuse. The IMEX and Securos clamps were more subject to degradation than the KE clamp and this may have clinical importance for fixator composite rigidity. CLINICAL RELEVANCE Fracture-reduction stability is related to the ability to resist motion within a clamp. The unpredictable nature of degradation we found cautions against repeated use. Clinicians should consider reuse of external fixator clamps with the knowledge that repeated use degrades clamp mechanical performance.