The Sourcil Sign: A Useful Finding on Plain X-ray?

Abstract

Background The radiographic finding of the ‘sourcil sign’ from plain X-ray has previously been suggested to be an indicator of rotator cuff pathology. However, little evidence exists to support this hypothesis. We set out to clarify whether plain X-rays changes are a useful adjunct for the diagnosis of rotator cuff disease. Methods The radiographs of 175 patients presenting to an orthopaedic shoulder clinic with shoulder pain were evaluated for the presence of the ‘sourcil sign’ by a single observer, blinded to the patient's diagnosis. A second observer, blinded to the radiological findings, examined the patient's medical notes to determine the diagnosis. The patients were divided into age groups of each decade. Results Sensitivity, specificity, positive predictive value and negative predictive value were all poor for the radiological signs as predictors of rotator cuff pathology, regardless of age. The incidence of the sourcil sign did not correlate with impingement syndrome, rotator cuff tears or age. Conclusion The results obtained demonstrate that the sourcil does not aid the diagnosis when seen.