Prospective evaluation of the McMurray test.

The accuracy and interexaminer reliability of the McMurray test for the diagnosis of meniscal tears were compared with arthroscopic findings in a prospective study of 104 consecutive patients awaiting elective arthroscopy. The only significant McMurray sign found to correlate with meniscal injury was a "thud" elicited on the medial joint line with a medial meniscal tear (P = 0.05) that had a fair interexaminer reliability (kappa = 0.35). The sensitivity of a medial thud was 16%, and the specificity was 98% with a positive predictive value of 83%. Examiner experience had little effect on the accuracy of diagnosis of medial meniscal tears. This study supports the continued but limited emphasis on the McMurray test in the clinical diagnosis of meniscal tears.