Assessment of Intra- and Inter-observer Measurement Variability in a Radiographic Metacarpophalangeal Joint Osteophytosis Scoring System for the Horse

Abstract

The study evaluated the intra- and inter-observer measurement variability of an osteophytosis metacarpophalangeal joint scoring system. Ten (n = 10) dorso/palmar, latero/medial, and oblique views of equine metacarpophalangeal joints affected by osteoarthritis were examined. Nine assessment points were graded (scale: 0–3) twice by five veterinary students (inexperienced group, I) and four equine veterinary surgeons (expert group, E). The grades for each of the nine factors were summed to obtain the osteophytosis score. The variability between the two measurements was −2.04 ± 3.5, 95% CI −3.04 to −1.03 for the I group. For the E group, they were 0 ± 1.43, 95% CI −0.45 to 0.45. In the evaluation of the same radiographs, the I group had a coefficient of variability (CV) of 37.29%. The correlation was r = 0.90%. The CV between groups was 28.85%. The mean difference between the two observations was -0.03 ± 0.29 in the E group and 0.22 ± 0.77 in the I group. The I group showed a greater CV when the score was low (r = −0.78) compared to the E group, where the CV was independent of severity of osteophytosis (r = −0.47). The osteophytosis scoring system is an easily applicable and feasible system to be used by observers with different levels of experience, but inexpert observers may need additional training or may need to be helped by reference images. These data are validated by the low inter- and intra-observer measurement variability results in the E group. Therefore, the scoring system proposed seems to be a repeatable instrument applicable to the radiographic score of the severity of metacarpophalangeal joint osteoarthritis.

Elastosonographic features of the metacarpophalangeal joint capsule in horses

“…To facilitate comparisons between sound horses and horses affected by different degrees of metacarpophalangeal OA, radiographic and ultrasonographic joint scores were assigned to each joint. The radiographic score was assigned based on the evaluation of osteophytosis development in a four-degree system for judgement (0–3), corresponding to a progressive worsening stage of OA [ 12 ]. Osteochondral irregularities, an increased and heterogeneous plica, and an increased thickness of the joint capsule were evaluated to assign the ultrasonographic score using a scale ranging from 0 to 14 points, modified from Yamada and its colleagues [ 13 ] [ Supplementary material ].…”

Radiographic texture of the trabecular bone of the proximal phalanx in horses with metacarpophalangeal osteoarthritis

“…The selected radiographic examinations underwent analysis to determine the presence and severity of osteoarthritis. This assessment categorized the condition into the following four grades according to the criteria established by Silva et al (2019) and Lacitignola et al (2020) [ 29 , 40 ], as outlined in Table 1…”