Reliability of radiologic classification for cuff tear arthropathy

Background: Several classification schemes have been proposed for cuff tear arthropathy and used for scientific and clinical purposes, even though their reliability has not been established and compared as of yet. Materials and methods: Two observers (O1 and O2) twice independently classified 52 shoulder radiographs into the cuff arthropathy schemes of Favard, Visotsky-Seebauer, Hamada, and Sirveaux. The schemes of Samilson and Prieto as well as Kellgren and Lawrence, commonly used for osteoarthritis of the shoulder, were also used for comparison. Reliability was tested with the kappa coefficient. Results: The intraobserver and interobserver reliabilities were 0.812 for O1, 0.710 for O2, and 0.305 for O1 versus O2 for the Favard classification; 0.868, 0.583, and 0.551, respectively, for the Visotsky-Seebauer classification; 1.000, 0.491, and 0.407, respectively, for the Hamada classification; and 0.852, 0.602, and 0.598, respectively, for the Sirveaux classification. For comparison, the Samilson-Prieto classification reached 0.815, 0.710, and 0.507, respectively, and the Kellgren-Lawrence scheme reached 0.815, 0.713, and 0.430, respectively. Discussion: Of the classification schemes tested, the Sirveaux classification displayed the best reliability overall. The Sirveaux classification only respects alterations of the glenoid, however. Among the schemes respecting both the glenoid and the humerus, the Hamada and Visotsky-Seebauer schemes showed similar reliability compared with the Samilson-Prieto and Kellgren-Lawrence systems, whereas the Favard classification was not as reliable. We therefore recommend the Visotsky-Seebauer or Hamada classification scheme. Level of evidence: Level I, Diagnostic Study. (C) 2011 Journal of Shoulder and Elbow Surgery Board of Trustees.