Sensitivity and Specificity of MRIs in the Identification of Hip Labral Tears

Abstract

Hip labral tears can be identified from both radiologic or clinical evaluations. Radiologic evaluations are often used to confirm a suspected tear, mainly through magnetic resonance imaging (MRI) or magnetic resonance arthrogram (MRA). However, the diagnostic accuracy of these tests has been found to be inconsistent in previous research. Thus, the gold standard in diagnosis is surgical exploration. The purpose of this study was to determine the reliability of MRIs for diagnosis of hip labral tears. Chart reviews were conducted to compare arthroscopic surgical repair against radiologist report findings. Sensitivity and specificity were then calculated. Six hundred four (604) patients underwent a labral tear between January of 2017 and May of 2019, 200 subjects did not fit the study criteria resulting in 404 subjects being enrolled in this study. Of those, 128 were male and 276 were female. The radiologists identified 217 true positives, 1 false positive, 184 false negatives, and 2 true negatives. This yields a sensitivity of 54.1% and a specificity of 66.6% for the radiologist. With respect to the physician, the study reported 367 true positives, 2 false positives, 34 false negatives, and 1 true negative. This resulted in a sensitivity of 91.5% and a specificity of 33.3% for the physician. The sensitivity of MRIs has been reported between 25% and 67% and specificity between 67% and 79% in diagnosing labral tears. This study found that the physician was able to correctly identify labral tears more reliably than the radiologist. The significance of this study is that radiologists are under diagnosing labral tears resulting in many patients being denied insurance coverage by insurance for surgical repair.