Reliability of radiologic glenohumeral osteoarthritis classifications.

BACKGROUND: This study was conducted to determine the intraobserver and interobserver reliability of glenohumeral osteoarthritis classification schemes.
MATERIALS AND METHODS: The plain radiographs of 108 shoulder joints from 96 consecutive patients with glenohumeral osteoarthritis treated at our institution were graded into 6 classification systems by 2 observers on 2 occasions. The intraobserver and interobserver reliability of the classification schemes were determined by using Cohen's κ coefficient and weighted according to Landis and Koch.
RESULTS: The intraobserver and interobserver reliabilities were 0.907 (observer 1), 0.965 (observer 2), and 0.851 (interobserver) for the Samilson-Prieto grading system; 0.954, 0.948, and 0.869 for the Allain modification; 0.936, 0.830, and 0.791 for the Gerber modification; 0.887, 0.892, and 0.744 for the Kellgren and Lawrence classification; 0.873, 0.964, and 0.935 for the Weinstein; and 0.854, 0.934, and 0.797 for the Guyette grading system.
CONCLUSION: The classification systems according to Weinstein and Guyette and the modifications of the Samilson-Prieto classification according to Allain and Gerber showed a comparable reliability with the commonly used glenohumeral osteoarthritis grading systems according to Samilson-Prieto and Kellgren-Lawrence. Thus, they are recommended for clinical and especially scientific purposes.