Introduction: The so-called Oram's sign states that the penis points to the side of the disorder on standard antero-posterior (AP) x-rays of the pelvis. The present study is a scientific evaluation of the sign in a relevant clinical context.
Material and methods: This is a retrospective study based on a blinded reading by four males and one female doctor of AP x-rays of the pelvis from 51 male patients with hip and pelvic disorders and 11 x-rays without pathology from an additional nine males and two females. The sensitivity and specificity and the positive and negative likelihood ratios were calculated together with the Kappa values for intra- and interobserver agreement.
Results: The sensitivity of Oram's sign for the individual reader varied between 40.3% and 25.8%. The overall sensitivity and specificity for all readers were 55% and 14%, respectively. The test performance did not show any significant variation between the male readers and the female reader. The sensitivity of Oram's sign in relation to the various pathologic findings varied between 32.1% for femoral neck fractures, 66.6% for osteoarthritis of the hip and 88.8% for pelvic fracture. Oram's sign could not be defined in 16.3% of the cases. The intra- and interobserver agreement was poor with relatively low Kappa values.
Conclusion: Oram's sign was not useful in this study on the diagnosis of hip fractures mainly due to a low sensitivity and too low observer agreement.