Comparison of conventional and digital measurements of tibial plateau angle in dogs.

Abstract

OBJECTIVE: To compare values for tibial plateau angle (TPA) obtained in dogs by conventional and digital methods. DESIGN: Evaluation study. ANIMALS: 37 dogs with stifle joint abnormalities. PROCEDURES: In all dogs, radiographs of both stifle joints were obtained by conventional and digital means. On conventionally acquired radiographs, TPA was measured with a protractor and fine-point pencil in accordance with standard guidelines. A software program was used to measure TPA on digitally acquired radiographs. Two viewers with different levels of experience performed all measurements 3 times. RESULTS: For both viewers and both limbs, conventional TPA measurements were significantly correlated with digital measurements all 3 times. Conventional and digital measurements obtained by viewer 1 were significantly different from values obtained by viewer 2. However, inter-viewer and intertechnique differences in TPA measurements resulted in rotational differences of < 1 mm. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that TPA measurements obtained with the digital method were comparable to those obtained by use of the conventional method. Subjectively, the digital method was easier to perform and faster and produced better-quality images.