Department of Orthopaedic Surgery, Colchester Hospital University National Health Service Foundation Trust, Colchester, United Kingdom.
Am J Sports Med. 2011 Dec;39(12):2575-81. doi: 10.1177/0363546511424872. Epub 2011 Oct 13.
Posterolateral corner (PLC) injuries are difficult to diagnose and cause significant morbidity. The ideal method for the dial test and its accuracy remain unclear.
This study compares the accuracy of measuring tibial external rotation at the skeletal level to measuring the patella-tubercle angle (PTA) and the thigh-foot angle (TFA) in the supine position to assess the most accurate method to measure rotation during the dial test.
Controlled laboratory study.
Measurements were compared simultaneously using rotational goniometers at a cutaneous splint over the tibia, at a foot splint, and directly from the tibial skeleton. Six lower limbs were used. The femur was held rigidly and the knee tested at 90° and 30° of flexion. External rotation torque up to 8 N·m was applied through the foot splint, and the rotations were measured by 2 testers.
Measurements at the tibial splint and directly on the tibia showed significant correlation at both knee flexion angles. The mean tibial external rotation was 24° at 90° of flexion and 26° at 30° of flexion (P < .05). The soft tissue effect caused the tibial splint to overestimate rotations by a mean of 6° and 9° at 90° and 30° of flexion, respectively. Foot splint measurements did not correlate significantly with tibial rotation, overestimating rotations by a mean of 103%. Intratester and intertester intraclass correlations were significant for the skin-mounted tibial splint measurements at both flexion angles but not for foot splint measurements at either flexion angles.
Rotation of the foot did not accurately represent the tibial external rotation at the knee, which could be measured more accurately by an instrument resting on the skin via a molded tibial splint. These results suggest that the PTA, and not the TFA, should be used in the dial test. This would support the use of the supine position during the dial test.
The dial test is a commonly used method for diagnosing PLC injuries. This study helps to identify the ideal position and measuring points to use for this test; measurements based on the tibia were more accurate than those that used rotation of the foot.
后外侧角（PLC）损伤难以诊断，且会导致严重的发病率。Dial 试验的理想方法及其准确性仍不清楚。
本研究比较了在仰卧位下测量胫骨外旋的骨骼水平与测量髌韧带-胫骨结节角（PTA）和大腿-足角（TFA），以评估在 Dial 试验中测量旋转时最准确的方法。
对照实验室研究。
使用旋转角度计同时在胫骨皮肤夹板、足夹板和胫骨骨骼上进行测量。使用 6 条下肢。股骨被刚性固定，膝关节在 90°和 30°屈曲下进行测试。通过足夹板施加高达 8 N·m 的外部旋转扭矩，并由 2 名测试员测量旋转。
在膝关节屈曲的两个角度下，胫骨夹板和直接在胫骨上的测量均显示出显著相关性。平均胫骨外旋在 90°时为 24°，在 30°时为 26°（P<.05）。软组织效应导致胫骨夹板在 90°和 30°时分别高估旋转 6°和 9°。足夹板测量与胫骨旋转无显著相关性，平均高估旋转 103%。在两个屈曲角度下，皮肤固定的胫骨夹板测量的组内相关系数在测试者内和测试者间均有显著意义，但在两个屈曲角度下的足夹板测量均无显著意义。
足部的旋转不能准确代表膝关节的胫骨外旋，可以通过放置在皮肤上的仪器通过模制的胫骨夹板更准确地测量。这些结果表明，应该在 Dial 试验中使用 PTA，而不是 TFA。这将支持在 Dial 试验中使用仰卧位。
Dial 试验是诊断 PLC 损伤的常用方法。本研究有助于确定该试验的理想位置和测量点；基于胫骨的测量比基于足部旋转的测量更准确。
