Interobserver Reliability among Radiologists and Orthopaedists in Evaluation of Chondral Lesions of the Knee by MRI

Objective. The aim of this study was to evaluate interobserver reliability in the presence of chondral injuries of the knee among radiologists, orthopaedic surgeons, radiologists, and orthopaedic surgeons. Methods. This was a prospective, web-based multi-institutional survey, consisting of 6 magnetic resonance exams of knee chondral injuries and a questionnaire to be completed by the participants. Two radiologists and two orthopaedic surgeons were enrolled, with more than 5 years of clinical experience. Kappa statistics test was used to calculate interobserver reliability between participants. Results. Kappa ranged from -0.13 through 0.29 between orthopaedists; from 0.06 through 0.78 between radiologists; from -0.10 through 0.24 between orthopaedists and radiologists. Cases 3 and 6 had skewed results among radiologists: with Kappa scores of 0.78 and 0.53, respectively. Conclusions. Our study reveals that the interobserver agreement between radiologists is higher than among orthopaedists in the evaluation of chondral knee lesions by MRI.