Snapping or grating scapula is a condition of the shoulder girdle in which the patient complains of pain and an audible snapping sound which may be associated with pain. We evaluated the diagnostic value of the computed tomography (CT) scans using the clinical diagnosis of a grating scapula as the gold standard. This retrospective study reports the sensitivity, specificity, likelihood ratio and receiver operator characteristic curve for the CT scans and the κ value as a measure of the interobserver agreement. None of the parameters validated the examination. We therefore concluded that CT scans are inappropriate for differentiation between a grating scapula and a normally functioning shoulder except in cases where bony abnormalities are present.