McMurray's Test and Joint Line Tenderness for Medial Meniscus Tear: Are They Accurate?

Background: Meniscus tears are the most common injury of the knee. The McMurray's test and Joint line tenderness for diagnosing meniscus tear have been widely tested, but results reported by different authors vary. The wide variations reported have an impact on clinical decision concerning whether to go for other diagnostic tests before going for diagnostic arthroscopy, which is considered as the gold standard.The purpose of this study was to determine the diagnostic value of Joint line tenderness and McMurray's test, as clinical signs, to diagnose underlying medial meniscus tears.

Methods: This was a prospective observational study done in Tribhuwan University Teaching Hospital. Patients undergoing knee arthroscopy were included in the study period of one year (from February 2011 to January 2012). Each patient was clinically examined with McMurray's test and joint line tenderness. The findings were then matched by the arthroscopic findings. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were then calculated.

Results: The sensitivity, specificity, positive predictive value , negative predictive value and accuracy for medial joint line tenderness in diagnosing medial meniscus tear were 50%, 61.7%, 51.8%, 60% and 56.45% respectively. The result was insignificant (p value=0.352). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for McMurray's test for diagnosing medial meniscus tear were 54%, 79%, 68% , 67.50% and 67.74% respectively. The result was significant (p value=0.007).

Conclusion: Clinical tests like McMurray and joint line tenderness have low diagnostic value when applied individually. They may be useful when combined together with the background of clinical history. The decision to scope the knee should not be solely taken on the results of clinical tests.