Tetro A M, Evanoff B A, Hollstien S B, Gelberman R H
Washington University School of Medicine, St Louis, Missouri 63110, USA.
J Bone Joint Surg Br. 1998 May;80(3):493-8. doi: 10.1302/0301-620x.80b3.8208.
To establish the value of median nerve compression with wrist flexion as a provocative test for carpal tunnel syndrome (CTS), we performed a prospective study of 64 patients (95 hands) with CTS confirmed by electrodiagnostic studies and 50 normal subjects (96 hands). We recorded results for the common provocative tests (Tinel's percussion test, Phalen's wrist flexion test and the carpal compression test) and the new test which combines wrist flexion with median nerve compression. Using a receiver operator characteristic curve (ROC) technique, we found that the optimal cut-off time for the wrist-flexion and median-nerve compression test was 20 s, giving a sensitivity of 82% and a specificity of 99%. These results were significantly better than for Phalen's wrist flexion test (61% and 83%, respectively) and for the sensitivity of Tinel's test (74%). The positive predictive values of the wrist flexion and median-nerve compression test, which is more important clinically, were 99%, 95% and 81% at population prevalences of 50%, 20% and 5%, respectively. These were significantly better than those of the three other provocative tests at each prevalence. Electrodiagnostic studies have significant false-positive and false-negative rates in CTS, and therefore provocative tests remain important in its diagnosis. We have shown that wrist flexion combined with the median-nerve compression test at 20 s, is significantly better than the other methods, and may thus be clinically useful.
为确定腕关节屈曲时正中神经受压作为腕管综合征（CTS）激发试验的价值，我们对64例经电诊断研究确诊为CTS的患者（95只手）和50名正常受试者（96只手）进行了一项前瞻性研究。我们记录了常见激发试验（Tinel叩击试验、Phalen腕关节屈曲试验和腕管压迫试验）以及将腕关节屈曲与正中神经受压相结合的新试验的结果。使用受试者工作特征曲线（ROC）技术，我们发现腕关节屈曲加正中神经受压试验的最佳截断时间为20秒，灵敏度为82%，特异度为99%。这些结果明显优于Phalen腕关节屈曲试验（分别为61%和83%）以及Tinel试验的灵敏度（74%）。在人群患病率分别为50%、20%和5%时，临床上更重要的腕关节屈曲加正中神经受压试验的阳性预测值分别为99%、95%和81%。在每种患病率下，这些结果均明显优于其他三种激发试验。电诊断研究在CTS中存在显著的假阳性和假阴性率，因此激发试验在其诊断中仍然很重要。我们已经表明，20秒的腕关节屈曲加正中神经受压试验明显优于其他方法，因此可能具有临床应用价值。
