Navicular Syndrome: Preliminary Assessment of Radiographic Scoring

Summary

The purpose of this preliminary study was to record observer agreement in the assessment of navicular bone radiographs. This was performed to assess whether a navicular lesion scoring system would augment tests currently available. Radiographs from both normal horses and horses affected with navicular disease were used in the study.

The dorsoproximal-palmarodistal oblique (65°) view of both forefeet of 54 individuals were assessed in an independent and unprejudiced manner by two observers, six months apart. The total synovial fossae score and the total number of lesions seen were recorded and intra-class correlation coefficients determined. From this the level of intraobserver and inter-observer agreement was determined. Substantial intra-observer agreement (ICC 0.61–0.80) for total synovial fossae score and total number of lesions was attained by one observer (No. 2) whilst the other (No. 1) attained only poor to moderate aggreement (ICC 0.40–0.60). The interobserver agreement ranged from moderate to substantial.

In view of the inconsistency seen, in this preliminary evaluation, it is our belief that a navicular scoring system would not augment currently available diagnostic tests.

This preliminary study examines the consistency of observer agreement for evaluation of navicular bone radiographs. A low level of observer aggreement, and hence consistency, was seen. The results suggest that the use of a navicular scoring system to augment diagnostic tests may be of little value.

Keywords

Navicular syndrome - radiographic assessment - consistency

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