Diagnostic accuracy of radiographs for the diagnosis of humeral intracondylar fissure in dogs.

OBJECTIVES

To assess the diagnostic accuracy of radiographs in identifying humeral intracondylar fissures in dogs.

MATERIALS AND METHODS

Clinical data from dogs undergoing CT and radiographic elbow investigations at a single institution were reviewed. Based on CT diagnosis, radiographs were classified as having fissures and not having fissures. The radiographic images were evaluated by three blinded observers for the presence/absence of a fissure, type (partial or complete), and for secondary signs that could suggest the presence of a fissure in case this was not visible.

RESULTS

A total of 81 radiographs (76 elbows) were reviewed. Based on CT findings, 37 elbows had fissures and 44 did not. Radiographic interpretation demonstrated a sensitivity of 47.7% (confidence interval 95%: 0.40 to 0.59) and specificity of 85.6% (confidence interval 95%: 0.72 to 0.93) in correctly identifying humeral intracondylar fissures. The positive predictive value was 75.5% (confidence interval 95%: 0.64 to 0.84) and the negative predictive value was 66.1% (confidence interval 95%: 0.63 to 0.68). Agreement with CT images was <0.4, and interobserver and intraobserver agreements were <0.8. The radiographic orientation and type of fissure did not significantly affect interpretation outcomes.

CLINICAL SIGNIFICANCE

Radiographic imaging alone is insufficient for reliably diagnosing humeral intracondylar fissures in dogs.