Diagnostic accuracy of a new clinical test (resisted internal rotation) for detection of gluteus medius tears
The objective of this study was to evaluate the diagnostic accuracy of a new dynamic clinical examination for detection of gluteus medius (GM) tears. A case group of 50 patients undergoing arthroscopy with GM repair was compared with a control group of 50 patients undergoing arthroscopy who had no peritrochanteric symptoms. Both groups were examined clinically, had magnetic resonance imaging studies performed and underwent arthroscopic surgery. Recorded clinical examinations included abnormal gait (Trendelenburg), tenderness to palpation of the greater trochanter, resisted abduction and the test being studied, resisted internal rotation. For all clinical tests, the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy rates were calculated and compared with the arthroscopic and MRI data for the case group, and the MRI data for the control group. The resisted internal rotation test had a sensitivity of 92%, specificity of 85% and diagnostic accuracy of 88% in the detection of GM tears, with a low rate of false-positive and false-negative recordings. Other traditional clinical examination tests, with the exception of Trendelenburg gait, showed inferior rates. Trendelenburg gait had a higher specificity, but much lower sensitivity. The resisted internal rotation test aides in the detection of GM pathology. Due to the good results of the resisted internal rotation test in all the diagnostic parameters, we recommend incorporating it on the physical exam of patients with hip pain.