Perioperative analgesic efficacy of lumbar erector spinae plane block in dogs undergoing hemilaminectomy: a randomized blinded clinical trial.

OBJECTIVE: To evaluate the perioperative analgesic effect of the unilateral lumbar erector spinae plane block (ESPBL) in dogs undergoing hemilaminectomy. STUDY DESIGN: Randomized, blinded clinical study. ANIMALS: A total of 30 client-owned dogs undergoing thoracolumbar or lumbar hemilaminectomy for intervertebral disc extrusion (IVDE). METHODS: Dogs were randomly assigned to receive a unilateral ESPBL, performed either with 0.4 mL kg-1 ropivacaine 0.5% [group ROPI (n = 15)] or with saline solution [CNT group (n = 15)]. Dogs were premedicated intravenously (IV) with acepromazine 5 µg kg-1 and methadone 0.2 mg kg-1, general anaesthesia was induced by administering IV midazolam 0.2 mg kg-1 and propofol to effect and maintained with isoflurane. Fentanyl was administered as rescue analgesia. Bradycardia [heart rate (HR) < 60 beats minute-1] with hypotension was treated with atropine IV. The Short-Form of the Glasgow Composite Pain Scale was used pre- and postoperatively at 1, 2, 4, 8, 12, 16, 20 and 24 hours after extubation, and methadone 0.2 mg kg-1 was administered IV when pain score was ≥ 5/20. HR and end-tidal concentration of isoflurane (Fe'Iso) were compared between groups with anova combined with a Dunnet's post hoc test. Time to the first rescue methadone and total dose of fentanyl (FENtot, µg kg-1 hour-1) and methadone (METtot, mg kg-1) in the first 24 postoperative hours were compared using unpaired Student's t test. Postoperative pain scores were compared with the Mann-Whitney test and atropine administration with a Fisher's exact test; p < 0.05. RESULTS: HR, Fe'Iso, FENtot, METtot and atropine administration were significantly lower in group ROPI compared to CNT. Postoperative analgesic effect was significantly longer, and pain scores were significantly lower in group ROPI for all time points. CONCLUSIONS AND CLINICAL RELEVANCE: Unilateral ESPBL with ropivacaine reduced perioperative opioid consumption and the occurrence of bradycardia in dogs undergoing hemilaminectomy.

Compressive mechanical properties of dry antler cortical bone cylinders from different cervidae species.

Antlers are bony structures composed predominantly of primary osteons with unique mechanical properties due to their specific use by deer as weapon and shield. Antler bone fracture resistance has attracted prior scrutiny through experimental tests and theoretical models. To characterize antler mechanical properties, compression of cubes, or bending or tensioning of rectangular bars have been performed in the literature with variations in the protocols precluding comparisons of the data. Compression testing is a widely used experimental technique for determining the mechanical properties of specimens excised from cortical or cancellous regions of bone. However, the recommended geometry for compression tests is the cylinder, being more representative of the real performances of the material. The purpose of research was to report data for compressive strength and stiffness of antler cortical bone following current guidelines. Cylinders (n = 296) of dry antler cortical bone from either the main beam or the tines of Cervus elaphus, Rangifer tarandus, Cervus nippon and Damadama were tested. This study highlights the fact that compression of antler cortical bone cylinders following current guidelines is feasible but not applicable in all species. Standardization of the testing protocols could help to compare data from the literature. This study also confirms that sample localization has no effect on the mechanical properties, that sample density has a significant impact and allows enriching the knowledge of the mechanical properties of dry antler cortical bone.

Presumed concurrent medial coronoid process fracture is a frequent radiographic finding in dogs and cats with humeral condylar fractures.

OBJECTIVE: To report the prevalence of presumed concurrent medial coronoid process fractures in a series of cases of humeral condylar fractures and evaluate factors influencing the presence of a suspected fracture of the medial coronoid process. ANIMALS: 48 dogs and 7 cats, with a total of 57 humeral fractures. METHODS: Medical records of dogs and cats diagnosed with a humeral condylar fracture with radiographs were reviewed between October 2013 and March 2022. Species, sex, neutered status, age, weight, and the nature of the trauma were noted. Radiographs were assessed for the configuration of humeral condylar fracture, the presence of a suspected fractured medial coronoid process (MCP), number of MCP fragments, nature of fracture, degree of radioulnar incongruity, soft tissue swelling, and elbow luxation/subluxation. RESULTS: A presumed fracture of the MCP was seen in 26 of 57 cases. Comminution of the condylar fracture was the only parameter that had a positive effect on the presence of a possible fractured MCP. Body weight was significantly associated with size of the suspected fractured MCP. The presence of this fracture was not associated with the type of humeral condylar fracture. The size of the presumed fractured MCP fragment was positively correlated with body weight. CLINICAL RELEVANCE: There was a high prevalence of presumed fractured MCPs in dogs with humeral condylar fractures (almost 50%) and even more so in animals with comminuted fractures. The consequences of suspected fractured MCP associated with humeral condylar fractures and whether dogs and cats would benefit from removal of the fragment remain unknown.

The Middle Ear Microbiota in Healthy Dogs Is Similar to That of the External Ear Canal.

Otitis media can be a consequence of chronic otitis externa and could represent a perpetuating factor. While the microbiota of the EEC in healthy dogs and in the presence of otitis externa has been described, only sparse information is available concerning the normal microbiota of the middle ear. The objective was to compare the tympanic bulla (TB) with the external ear canal (EEC) microbiota in healthy dogs. Six healthy experimental Beagle dogs were selected based on the absence of otitis externa, negative cytology and bacterial culture from the TB. Samples from the EEC and TB were collected directly after death using a total ear canal ablation and lateral bulla osteotomy. The hypervariable segment V1-V3 of the 16S rDNA was amplified and sequenced with a MiSeq Illumina. The sequences were analyzed by the Mothur software using the SILVA database. No significant differences between the EEC and TB microbiota for the Chao1 richness index (p = 0.6544), the Simpson evenness index (p = 0.4328) and the reciprocal Simpson alpha diversity (p = 0.4313) were noted (Kruskal-Wallis test). A significant difference (p = 0.009) for the Chao1 richness index between the right and left EEC was observed. The microbiota profile was similar in the EEC and the TB of the Beagles.

Patellar Proximo-Distal Displacement following Modified Maquet Technique Is Not Predictive of Patellar Luxation.

OBJECTIVE: The aim of this study was to test the low sensitivity of the Allberg and Miles index to the stifle opening angle, evaluate the displacement of the patella after a Modified Maquet Technique using this index and assess the incidence of patellar luxation post-Modified Maquet Technique in dogs. STUDY DESIGN: Medical records were reviewed from 2012 to 2017. Allberg Miles index were determined for each stifle pre- and postoperatively, as well as the stifle joint opening of each case. Occurrence of patellar luxation was recorded. RESULTS: 137 stifles on 116 dogs were reviewed. The stifle opening angle did not influence the Allberg Miles index. Pre- and postoperative index showed a distal displacement of the patella after a Modified Maquet Procedure, especially at 135° of stifle opening angle. Only 1/137 cases demonstrated patellar luxation after the surgery. CONCLUSION: Based on our statistical analysis, we were able to conclude that within the maximum stifle opening angle range recorded in our series of cases; the Allberg Miles index variation was not significant. While patellar baja is clearly induced by the Modified Maquet Technique, the latter did not seem to predispose patients to post-operative patellar luxation in our study population.

Determination of the Stifle Angle at Standing Position in Dogs.

BACKGROUND: The cranial cruciate ligament rupture is one of the most common orthopaedic diseases encountered in dogs. Surgical techniques have been developed to stabilize the stifle, with an overall accepted benefit of tibial osteotomies among which is the tibial tuberosity advancement (TTA). Prior to surgery, the required TTA must be determined on a strict lateral radiographical view of the affected stifle with femur and tibia at an angle of 135° as initially recommended. This value, initially determined in only two dog breeds, has been considered the mean standard value of the canine stifle angle during the mid-stance phase. METHODS: We sought to determine if this particular stifle angle around mid-stance phase was similar among multiple dog breeds. We built up a custom-made radiographic system for stifle angle measurement in standing dogs. RESULTS: A mean value of stifle angle of 145° was obtained. Mean stifle angle at mid-stance phase in a healthy dog is regularly higher than 135° and is likely breed and individual dependent. CONCLUSIONS: The pre-operative measurement of the required TTA made on stifles in 145° extension, a value close to full physiological extension could contribute to decreasing the incidence of late post-operative meniscal lesion, consecutive to underestimation of TTA.

In vivo evaluation of deer antler trabecular bone as a reconstruction material for bone defects.

Availability of graft materials to fill up osseous defects has always been a concern in orthopaedic surgeries. Deer antler material is a primary bone structure that is easy to collect and could serve as a xenograft. This study examines the behaviour of red deer antler trabecular cylinders in critical size distal femoral epiphyseal defects in 11 rabbits, and evaluates the effect of the decellularization protocols. Two preparation regimes (A and B) were used, with and without lipids and proteins. Radiographs were taken immediately after surgery and after euthanasia 12 weeks post-implantation. Histological evaluation was performed on non-decalcified 10-µm sections with a van Gieson picro-fuchsin staining protocol. A region of interest was defined for each histological section, evaluating the inflammatory reaction, the fibrosis process, and the osteogenesis. Each histological section was microradiographed to evaluate bone contact, presence of synostosis, remodelling and ossification processes. All antler cylinders were successfully implanted. Final radiographic analysis demonstrated osteointegration of most implants at various stages. Light to moderate inflammation around the grafts was noted with only one case showing full encapsulation. A variable degree of intimacy between implant and host bone was evidenced, with bone remodelling and osteogenesis of various intensity being present in all implanted sites. No differences were found between group A and B. Removal of lipids and proteins in the grafts surprisingly did not seem to matter. Decellularization and sterilization protocols may be advocated. Although it presents several limitations, this study shows some promising results regarding antler trabecular bone osteointegration.

Gallbladder and Liver Lobe Torsion in a Young Cat Presented with Hemoabdomen.

An 11 mo old domestic shorthair presented with acute lethargy. The cat was hypothermic and bradycardic and had pale pink mucous membranes, poor pulses, and a distended abdomen. Point-of-care ultrasound identified significant abdominal effusion, which was diagnosed to be a hemoabdomen. Bloodwork revealed hyperlactatemia, regenerative anemia, neutrophilia, hypoproteinemia, hypoalbuminemia, and increased alanine aminotransferase. The cat received an allotransfusion and a subsequent canine xenotransfusion and received further supportive therapy. After stabilization, abdominal ultrasonography diagnosed a gallbladder and liver lobe torsion with hemoabdomen. Exploratory laparotomy confirmed the torsion of the right medial and quadrate hepatic lobes together with the gallbladder. Cholecystectomy and lobectomy of the affected lobes were performed using a surgical stapler. The cat was discharged after 4 days. Histopathology confirmed hemorrhagic infarction of the liver lobes and gallbladder, consistent with the described torsion, and the hepatic pseudocyst. It also demonstrated a mucocele in the gallbladder. One month postoperatively, the cat had totally recovered. Hepatic lobe torsion without neoplasia is a rare disease in cats, with variable clinical signs. Gallbladder torsion is a hitherto unreported condition in cats. This is the first report of gallbladder and liver lobe torsion with secondary hemoabdomen in a cat, successfully treated by one-stage surgery.