Reliability of a Quantitative Rating Scale for Assessment of Horses With Distal Tarsal Osteoarthritis

Abstract

Various radiographic rating scales have been described for use in horses with distal tarsal osteoarthritis but little information is available on their reliability. The aim of this study was to develop a radiographic rating scale based on the results of an expert consultation process (the Delphi process), and to test the reliability of the radiographic rating scale. Seven radiographic features were identified as important indicators of distal tarsal osteoarthritis and these were then incorporated in the radiographic rating scale, which used a 100-mm-long visual analog scale. On two occasions nine equine veterinarians applied the radiographic rating scale, and a verbal descriptive rating scale, to three sets of tarsal radiographs, each comprising four standard radiographic views. Reliability was assessed using Bland-Altman plots and by calculating the 95% agreement limits. Analysis of variance (ANOVA) was used to identify significant interactions between the ratings of different assessors made from different views and at each assessment. Rating of distal tarsal osteoarthritis was different for the nine assessors. The most precise second ratings were between 16 mm higher and 18 mm lower than the first. Significant variables were "joint," "assessor," and "assessment" (univariable ANOVA); and "joint and assessor" and "assessor and assessment" (multivariable ANOVA). The radiographic rating scale developed for interpretation of distal tarsal osteoarthritis was less reliable than a verbal descriptive rating scale.

An assessment of intra‐ and interobserver agreement of reporting orthopaedic findings on presale radiographs ofThoroughbred yearlings

“…In all but one radiographic projection, Labens et al . found osteophytes to be less reliable than other radiographic indicators of osteoarthritis of the distal tarsal joints when read by a number of observers. Classification of a continuous variable as either present or absent will result in inconsistency, particularly if a good definition of each category is not available.…”

“…Despite the entrenched use of radiography in equine orthopaedics, few studies have assessed the agreement of equine radiographic findings, and then only at specific sites . Only Groth et al .…”

Is there a relationship between clinical presentation, diagnostic and radiographic findings and outcome in horses with osteoarthritis of the small tarsal joints?

“…The numerical scoring system used in this study was easily applied. The allocated scores were based on a subjective evaluation of the joints supporting Labens et al (2007a) who showed that a verbal descriptive scale (mild/moderate/severe) is more accurate than a quantitative rating scale in assessing distal tarsal joint osteoarthritis.…”

Clinical significance of osseous spurs on the dorsoproximal aspect of the third metatarsal bone

“…Periarticular osteophytes may be a manifestation of osteoarthritis (OA) of the tarsometarsal (TMT) joint (Morgan 1972; Shelley and Dyson 1984). However, a group of experts recently rated spurs of low clinical significance in the diagnosis of distal tarsal joint OA (Labens et al . 2007).…”