Comparison of percutaneous cystolithotomy and open cystotomy for removal of urethral and bladder uroliths in dogs: Retrospective study of 81 cases (2014-2018).

OBJECTIVE: Compare percutaneous cystolithotomy (PCCL) and open cystotomy (OC) for removal of bladder and urethral uroliths. DESIGN: Retrospective study. ANIMALS: Client-owned dogs and cats that underwent PCCL (n = 41) or OC (n = 40) between January 1, 2014 and February 28, 2018 at a referral center. METHODS: Medical records of dogs and cats that underwent a PCCL or an OC were reviewed. History, signalment, physical examination, diagnostic tests, length of the procedure and anesthesia, complications, and duration of hospitalization were recorded. RESULTS: A total 17 cats (PCCL = 10; OC = 7) and 64 dogs (PCCL = 31; OC = 33) were included. There was no significant difference, regardless of species, in the mean surgical time (45 min [24-160 min] and 48.5 min [15-122 min] with P = .54 in dogs, P = .65 in cats) nor mean duration of anesthesia (90 min [50-120 min] and 98 min [54-223 min] with P = .87 in dogs, P = .08 in cats) in the PCCL and OC groups respectively. Number of uroliths did not affect duration of surgery in either group. Complete urolith removal was achieved in 98% of dogs and cats in both groups. The median hospitalization time was significantly shorter in the PCCL group for dogs (11.3 hours [range 4 to 51.3] in the PCCL vs 56.6 hours [range 7.3 to 96] in the OC group; P < .001) but did not differ for cats (24.5 hours [range 8.3 to 30] in the PCCL vs 56.6 hours [range 10.1 to 193.2] in the OC group; P = .08). CONCLUSION AND CLINICAL RELEVANCE: Bladder urolith removal by PCCL procedure is no longer than OC. Further studies are needed to compare the pain related to procedure between PCCL and OC.

Open reduction and cranial bone plate fixation of fractures involving the distal aspect of the radius and ulna in miniature- and toy-breed dogs: 102 cases (2008-2015).

OBJECTIVE To determine outcomes and complication rates of open reduction and cranial bone plate fixation of fractures involving the distal aspect of the radius and ulna in miniature- and toy-breed dogs. DESIGN Retrospective case series. ANIMALS 102 miniature- and toy-breed dogs (105 fractures) weighing ≤ 7 kg (15.4 lb) that had undergone open reduction and cranial bone plate fixation of a fracture involving the distal aspect of the radius and ulna from 2008 through 2015. PROCEDURES Medical records were reviewed and information extracted regarding dog and fracture characteristics, surgical variables, and follow-up examination data (including postoperative complications). Postoperative radiographs were examined for distal fragment size, implant placement, apposition, alignment, and healing stage. A long-term follow-up questionnaire was completed by telephone interview with dog owners at least 6 months after surgery. RESULTS Mean length of the distal bone fragment in all fractures was 19.2 mm, with a mean distal-to-total radial length ratio of 0.21. At last follow-up examination (typically 6 weeks after surgery), 97 (95%) dogs had no signs of lameness; minor lameness was identified in 5 (5%) dogs. Complications developed in 26 (25%) fractures (23 [22%] minor and 3 [3%] major complications). Sixty-eight of 71 (96%) owners rated the overall and long-term outcome as excellent and 3 (4%) as good; 68 of 71 (96%) dogs reportedly had no signs of residual lameness. CONCLUSIONS AND CLINICAL RELEVANCE Open reduction and cranial bone plate fixation for the treatment of radius-ulna fractures in miniature- and toy-breed dogs provided an excellent outcome with a low complication rate.

Effect of Intramedullary Rod Diameter on a String of Pearls Plate-Rod Construct in Mediolateral Bending: An In Vitro Mechanical Study.

OBJECTIVE: To evaluate the effect of intramedullary rod (IMR) diameter on the mechanical behavior of string of pearls (SOP) plate-rod constructs. STUDY DESIGN: In vitro mechanical study. SAMPLE POPULATION: Synthetic bone models (n = 24). METHODS: Locking 3.5 mm SOP plates were fixed to a tibial bone model with a 50 mm fracture gap. Four experimental groups (n = 4) were tested: monocortical SOP construct alone and monocortical SOP constructs augmented with a 2.4, 3.2, or 4.0 mm IMR corresponding to 24, 32, or 40% filling of the medullary cavity diameter (SOP-24, SOP-32, SOP-40). Control groups (n = 4) were stabilized with either a bicortical SOP plate (SOP-B) or a 3.5 mm limited contact dynamic compression plate (LC-DCP) with a 4.0 mm IMR filling 40% of the medullary cavity diameter (LC-DCP-40). Specimens were tested in mediolateral bending. Construct compliance (CC) and angular deformation (AD) were compared between construct types (P < .05). RESULTS: CC and AD incrementally decreased with increasing IMR diameter (P < .001). There were no statistical differences between SOP-24 and SOP-B (P = .806) or between SOP-32 and LC-DCP-40 (P = .773), which was also the least compliant of all constructs (P < .001). AD followed an identical pattern of significance. CONCLUSIONS: Biological osteosynthesis often relies on more compliant bridging constructs to promote beneficial micromotion at the fracture. Our study suggests use of a smaller diameter IMR (SOP-32) is comparable to a conventional plate-rod construct (LC-DCP-40). Should greater compliance be desired, an even smaller diameter IMR (SOP-24) may prove beneficial while as stable as an accepted bicortical construct (SOP-B).

Effect of screw type and distribution on the torsional stability of 3.5 mm string of pearls locking plate constructs.

OBJECTIVE: To evaluate the effects of screw type (mono- [M] versus bicortical [B]), number, and position on torsional stability of String of Pearls (SOP) locking plate constructs. STUDY DESIGN: In vitro mechanical study. METHODS: SOP plates (n = 32) were applied to bone models and divided into 8 groups named according to screw type (M or B) and position in each fragment relative to the fracture gap starting at the outermost plate hole. Positive and negative controls were MMM and BBB, respectively. Specimens were non-destructively tested in torsion. Compliance and angular deformation were statistically compared (P < .002). RESULTS: The MMM construct was most compliant (P < .001). Compliance decreased in groups with a single bicortical screw (P < .001). Compared to the MMM group, torsional compliance decreased in constructs where a single monocortical screw was replaced with a bicortical screw (P < .001). Compared with a centrally positioned bicortical screw, constructs with a bicortical screw in either outer- or innermost position were 15% and 23% less compliant, respectively (P < .001). Addition of a second bicortical screw/fragment further decreased compliance (P < .001). No significant difference was found between groups with 2 bicortical screws. The BBB construct was least compliant (P < .001). Group responses for angular deformation followed the same pattern of significance recorded for compliance. CONCLUSIONS: A minimum of 1 bicortical screw/fragment should be used to increase torsional stability of 3.5 mm SOP constructs. Positioning this screw at the inner- or outermost positions relative to the fracture is preferred, with the innermost position providing the greatest improvement in stability. Should further torsional stability be desired, increasing the number of bicortical screws is recommended. Clinically, these results may assist with preoperative planning of various fracture patterns.

Ileocecocolic volvulus in a German shepherd dog.

This report describes an ileocecocolic volvulus in a German shepherd dog with risk factors of previous abdominal surgeries and concurrent chronic enteropathy. Contrast-enhanced computed tomography (CT) with multiplanar reformatting was more sensitive than abdominal radiographs or ultrasound to obtain a diagnosis, because of the presence of a "whirl-sign" on CT. A combination of colopexy and cecopexy was succesfully used to treat the patient's condition.

Volvulus iléo-caeco-colique chez un Berger Allemand. Ce rapport de cas décrit un volvulus iléo-caeco-colique chez un Berger allemand ayant différents facteurs de risque incluant des chirurgies abdominales préalables à sa présentation et une entéropathie chronique. L'observation d'un 'whirl-sign' lors des reconstructions de l'examen tomodensitométrique a permis d'obtenir le diagnostic de volvulus et s'est révélé dans ce cas être plus sensible que les examens d'imagerie usuels, soit la radiographie ou l'échographie abdominale. Le traitement chirurgical a été effectué avec succès grâce à la combinaison d'une cecopexie et d'une colopexie.(Traduit par les auteurs).

Effect of screw insertion torque on mechanical properties of four locking systems.

OBJECTIVE: To evaluate the effect of screw insertion torque on the mechanical properties of four 3.5 mm locking systems: New Generation Devices (NGD), Securos (PAX), Synthes (SYN), and Veterinary Orthopedic Implants (VOI). STUDY DESIGN: In vitro mechanical study. METHODS: Screws were inserted at 1.5 Nm, 2.5 Nm, and 3.5 Nm torques, using dedicated drill guides and a calibrated torque screwdriver. Locking mechanisms were tested under shear loading conditions using a custom-design probe. Tests were conducted under displacement control until failure. Load to failure and interface stiffness were compared between and within groups using a two-factor ANOVA (P < .05). Failure modes were described. RESULTS: The SYN group had significantly greater mechanical properties compared to all other groups at any given insertion torque. Insertion torque had a significant effect on the PAX group, increasing the load to failure by 126% when increasing the insertion torque from 1.5 Nm to 3.5 Nm. Insertion torque had no significant effect on the mechanical properties of the VOI group and limited effect on the NGD and SYN groups. Single failure mode, by screw head decoupling or screw shaft fracture, occurred in the SYN and VOI groups, respectively. In contrast, NGD and PAX systems failed through a combination of screw decoupling and/or bending. CONCLUSIONS: Regardless of insertion torque, the SYN locking mechanism showed the highest failure loads, interfacial stiffness as well as consistent failure mode. These findings highlight the dependability of this system. When using the PAX system an insertion torque of at least 2.5 Nm should be recommended.

Use of surgery and mitoxantrone chemotherapy in a dog with disseminated lymphangiosarcoma.

CASE DESCRIPTION: A 5-year-old sexually intact male Giant Schnauzer was evaluated because of difficulty breathing and left pelvic limb swelling. Eighteen months previously, the patient had had intermittent left pelvic limb swelling, but the owner declined further testing at that time. CLINICAL FINDINGS: Physical examination revealed severe pitting edema of the left pelvic limb and prepuce and muffled heart sounds on thoracic auscultation. Results of thoracic radiography and thoracocentesis were consistent with chylothorax, and CT imaging of the thorax and abdomen revealed a mass involving the whole left sublumbar area. TREATMENT AND OUTCOME: In an attempt to treat the chylothorax, pleural omentalization and pericardectomy were performed. Histologic evaluation of several biopsy specimens harvested in the abdominal and thoracic cavities revealed disseminated lymphangiosarcoma. The patient recovered well from surgery, and mitoxantrone chemotherapy was administered. As of 10 months after surgery, the dog was clinically normal except for mild pelvic limb edema. CLINICAL RELEVANCE: The combination of clinical signs, multiple imaging features, surgical findings, and histologic examination findings enabled the final diagnosis of lymphangiosarcoma. Clinical management that included medical and surgical treatments and chemotherapy resulted in improved quality of life and extended survival time in a dog with metastatic lymphangiosarcoma.

Use of magnetic resonance imaging and histopathologic findings for diagnosis of an aneurysmal bone cyst in the scapula of a cat.

CASE DESCRIPTION: An 18-month-old spayed female domestic shorthair cat was evaluated because of left thoracic limb lameness. CLINICAL FINDINGS: A firm mass was palpable in the left scapular region. On the basis of clinical signs; results of radiographic, ultrasonographic, and cytologic evaluations; and findings on magnetic resonance imaging, an aneurysmal bone cyst (ABC) of the scapula was strongly suspected. TREATMENT AND OUTCOME: Considering the large size of the mass and the poor prognosis for return to function of the left thoracic limb, amputation was elected. Histologic evaluation ruled out a malignant process and was diagnostic for ABC originating from the left scapula. The patient recovered well and was ambulatory the day after surgery. Three years after surgery, the cat was healthy. CLINICAL RELEVANCE: The combination of radiography, regional ultrasonography, and magnetic resonance imaging enabled lesion structure and cavity content evaluation. However, final diagnosis was confirmed by histologic evaluation. To our knowledge, this is the first veterinary report of the use of magnetic resonance imaging in the characterization and diagnosis of an ABC.