Special clinical tests play an important role in physical examination and are thought to diagnose meniscal injury. Among the special tests, the original McMurray’s test, the modified version of the McMurray’s test, and joint-line tenderness are commonly used in practice. There is limited research that takes into consideration the time of injury in the diagnostic accuracy of such clinical test. Therefore, in chronic meniscal injury, the diagnostic accuracy of tests is unclear and questionable. The purpose of this study was to determine the most accurate clinical tests to diagnose a chronic meniscal injury.
Fifty patients were enrolled in this cross-sectional study from January 2016 to June 2017. The inclusion criteria were patients 16 yr old or older who had a chronic knee injury of at least 6 mo. All patients underwent physical examination then arthroscopy performed by the same surgeon. Five statistical parameters were calculated based on the formula: accuracy (%), sensitivity (%), specificity (%), positive predictive value (PPV %) and negative predictive value (NPV %).
The mean age was 25.7 yr (range, 16-44 yr; SD 6.8 yr). The modified McMurray’s test had the highest sensitivity for both medial (36.36%) and lateral lesions (35.29%). It also had the highest NPV (64.10% medial and 73.17% lateral) and PPV (72.73% medial and 66.67% lateral), as well as the highest accuracy at 66% (medial) and 72% (lateral). The original McMurray’s test had the lowest sensitivity for lateral lesions (18.75%); however, it had the highest specificity for both lesions (92.59% medial and 91.18% lateral). Joint-line tenderness had the lowest specificity at 89.29% (medial) and 87.88% (lateral), the lowest accuracy for medial lesions (60%), and the same accuracy as the original McMurray’s test (68%) for lateral lesions.
The results indicate that the original McMurray’s test, the modified version, and joint-line tenderness have overall low sensitivity and high specificity in diagnosing chronic meniscal tears. This study also highlights that the modified McMurray’s test had a higher accuracy than the original McMurray’s test and joint-line tenderness. However, in clinical practice these tests should be used in combination for more accurate diagnosis of chronic meniscal tears.
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