Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seodaemun-gu, Seoul, South Korea.
J Bone Joint Surg Am. 2012 Aug 15;94(16):e1181-7. doi: 10.2106/JBJS.K.00356.
Meniscal tears are very common. The so-called paradoxical McMurray test has been described and found to be positive for three different types of meniscal tears. However, to our knowledge, no study has evaluated the accuracy of this test. The purpose of the present study was to evaluate the accuracy of the paradoxical McMurray test compared with the conventional McMurray test. We also sought to determine whether there are other types of meniscal tears that would show positive results on the paradoxical McMurray test.
The authors evaluated 628 patients with meniscal tears (Group I) and 387 patients without meniscal tears (Group II), as confirmed by arthroscopy performed from June 2000 to May 2006. The results of both clinical examinations (the conventional and the paradoxical McMurray test) were recorded, and the paradoxical phenomenon as seen during arthroscopy was described. The sensitivity and specificity of each test were calculated and statistically analyzed.
The average patient age (and standard deviation) was 41.9 ± 15.6 years (range, ten to sixty-six years) in Group I and 40.3 ± 12.9 years (range, fifteen to sixty-three years) in Group II. The sensitivities of the McMurray test and the paradoxical McMurray test for diagnosing a meniscal tear were 41.9% (263 of 628) and 12.3% (seventy-seven of 628), respectively. The specificities of the two tests were 76.7% (297 of 387) and 99.2% (384 of 387), respectively. Compared with the conventional McMurray test, the paradoxical McMurray test showed significantly lower sensitivity but higher specificity. Apart from the three previously reported types of meniscal tears, a new type of meniscal tear in a discoid lateral meniscus also showed positive results with the paradoxical McMurray tests.
In conclusion, a positive paradoxical McMurray test is reliable for diagnosing a meniscal tear that has a large displaced meniscal flap. A long radial tear in the posterior one-third of the discoid lateral meniscus is a new type of meniscal tear with positive results on the paradoxical McMurray test.
半月板撕裂非常常见。所谓的反常麦氏征试验已经被描述并发现对三种不同类型的半月板撕裂呈阳性。然而，据我们所知，尚无研究评估该试验的准确性。本研究的目的是评估反常麦氏征试验与传统麦氏征试验相比的准确性。我们还试图确定是否存在其他类型的半月板撕裂会在反常麦氏征试验中出现阳性结果。
作者评估了 628 例半月板撕裂患者（I 组）和 387 例无半月板撕裂患者（II 组），均经 2000 年 6 月至 2006 年 5 月的关节镜检查证实。记录了两种临床检查（传统和反常麦氏征试验）的结果，并描述了关节镜下观察到的反常现象。计算并统计分析了每种检查的灵敏度和特异性。
I 组患者的平均年龄（标准差）为 41.9 ± 15.6 岁（范围：10 至 66 岁），II 组患者的平均年龄为 40.3 ± 12.9 岁（范围：15 至 63 岁）。麦氏征试验和反常麦氏征试验诊断半月板撕裂的灵敏度分别为 41.9%（263/628）和 12.3%（77/628）。两种试验的特异性分别为 76.7%（297/387）和 99.2%（384/387）。与传统麦氏征试验相比，反常麦氏征试验的灵敏度显著降低，但特异性更高。除了之前报道的三种半月板撕裂类型外，盘状外侧半月板的一种新类型的半月板撕裂在反常麦氏征试验中也呈阳性结果。
总之，反常麦氏征试验阳性对诊断有大的半月板撕裂瓣的半月板撕裂是可靠的。盘状外侧半月板后三分之一的长放射状撕裂是一种新类型的半月板撕裂，在反常麦氏征试验中呈阳性结果。
