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BackgroundThe Dachshund is a chondrodystrophic breed of dog predisposed to premature degeneration and calcification, and subsequent herniation, of intervertebral discs (IVDs). This condition is heritable in Dachshunds and breeding candidates are screened for radiographically detectable intervertebral disc calcification (RDIDC), a feature of advanced disc degeneration and a prognostic factor for clinical disease. RDIDC scoring has been previously shown to be consistent within scorers; however, strong scorer effect (subjectivity) was also reported. The aim of this study was to estimate the within- and between-scorer agreement (repeatability and reproducibility, respectively) of computed tomography (CT) scanning and magnetic resonance imaging (MRI) for scoring IVD calcification, and to compare these modalities with radiographic scoring.ResultsTwenty-one Dachshund dogs were screened for IVD calcification using the three imaging modalities. Three scorers scored each case twice, independently. Repeatability was highest for radiography (95.4%), and significantly higher than for CT (90.4%) but not MRI (93.8%). Reproducibility was also highest for radiography (92.9%), but not significantly higher than for CT or MRI (89.4% and 86.4%, respectively). Overall, CT scored IVDs differently than radiography and MRI (64.8% and 62.7% agreement, respectively), while radiography and MRI scored more similarly (85.7% agreement).ConclusionsDespite high precision for radiography, previous evidence of scorer subjectivity was confirmed, which was not generally observed with CT and MRI. The increased consistency of radiography may be related to prior scorer experience with the modality and RDIDC scoring. This study does not support replacing radiography with CT or MRI to screen for heritable IVD calcification in breeding Dachshunds; however, evaluation of dog-level precision and the accuracy of each modality is recommended.

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Objective: To report anconeus muscle injury in a greyhound. Animal: One 11-month-old female greyhound. Study design: Case report Methods: The dog presented with a 6-week history of mild left foreleg lameness. Moderate pain was noted by palpation over the proximolateral ulna and distolateral humerus and by maximal elbow flexion. A laminar periosteal reaction on the caudodistal humerus was present on radiographs. At ultrasonic examination, disorganization of anconeus muscle fibers, and focal mixed echogenicity were noted. Precontrast and postcontrast computed tomography (CT) revealed a thin rim of periosteal new bone on the caudodistal humerus as well as heterogeneous contrast enhancement of soft tissue immediately caudal to the distal humerus. An unrelated greyhound cadaver dissection confirmed only the anconeus muscle attached to the site of noted periosteal reaction. A partial tear of the anconeus muscle was diagnosed. Treatment consisted of 4 weeks of oral meloxicam. Confinement space and exercise were incrementally increased over 14 weeks. Results: Muscle healing was confirmed by ultrasonography and CT. The dog was able to have a successful racing career spanning 2 years with no lameness attributable to the previous anconeus muscle injury and retired for unrelated reasons. Conclusion: Radiography and ultrasonography helped diagnose anconeal muscle injury, and conservative management led to full return to function. Clinical significance: Clinicians should include anconeus muscle injury as a differential diagnosis in dogs with lameness and pain over the proximolateral ulna or distolateral humerus or on elbow flexion.