Department of Orthopaedic Surgery, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Knee Surg Sports Traumatol Arthrosc. 2012 Jul;20(7):1323-30. doi: 10.1007/s00167-011-1643-5. Epub 2011 Aug 18.
Rotational instability in ACL insufficient knee addresses the symptom or the abnormal motion which can be reproduced and subjectively evaluated in the clinical exam. Clinically available quantitative measurement for this instability has not been established due to mixed testing maneuvers and complex kinematics. The purpose was to measure knee kinematics during three manually performed rotational tests and to determine the optimal method to detect the abnormality in ACL deficient knees.
Thirteen unilateral ACL deficient patients were tested by internal and external pure rotational stress tests and pivot shift test under anesthesia before scheduled ACL reconstructions. Rotation and coupled motion, i.e., tibial anteroposterior translation, were measured using an electromagnetic measurement system. Additionally, the acceleration of the tibial posterior translation during pivot shift test was calculated. The differences of these parameters between ACL intact and deficient knees were tested.
Knee rotation is not different between ACL intact and deficient during both pure rotational stress test and pivot shift test. The coupled anterior tibial translation during pivot shift test was significantly different between ACL intact, 13.5 ± 4.1 mm, and deficient knees, 23.1 ± 4.4 mm, (P < 0.01) as well as the acceleration of the tibial posterior translation (1.1 ± 0.4 m/sec(2) in intact knees, 3.2 ± 1.5 m/sec(2) in deficient knees; P < 0.01). The coupled motion during pure rotational stress tests was similar regardless of ACL condition.
The rotational instability of the ACL deficiency was reproduced only by the pivot shift test and detected only by measuring the tibial anteroposterior translation and acceleration of the tibial posterior reduction. Level of evidence Diagnostic study, Level III.
ACL 不足膝关节的旋转不稳定性涉及到可以在临床检查中重现和主观评估的症状或异常运动。由于测试动作混合和运动学复杂，尚未建立用于这种不稳定性的临床可用的定量测量方法。目的是测量三种手动进行的旋转测试期间的膝关节运动，并确定检测 ACL 缺陷膝关节异常的最佳方法。
在预定的 ACL 重建前，对 13 例单侧 ACL 缺陷患者进行了内侧和外侧纯旋转应力测试以及枢轴转移测试下的麻醉测试。使用电磁测量系统测量旋转和耦合运动，即胫骨前后平移。此外，计算了在枢轴转移测试中胫骨后移的加速度。测试 ACL 完整和缺陷膝关节之间这些参数的差异。
在纯旋转应力测试和枢轴转移测试中，ACL 完整和缺陷膝关节之间的膝关节旋转没有差异。在枢轴转移测试中，胫骨后移的耦合前平移差异非常显著，ACL 完整膝关节为 13.5±4.1mm，ACL 缺陷膝关节为 23.1±4.4mm（P<0.01），胫骨后移的加速度也有差异（完整膝关节为 1.1±0.4m/sec²，缺陷膝关节为 3.2±1.5m/sec²；P<0.01）。无论 ACL 条件如何，纯旋转应力测试中的耦合运动都相似。
仅通过枢轴转移测试再现 ACL 缺陷的旋转不稳定性，并通过测量胫骨前后平移和胫骨后移加速度来检测。
诊断研究，III 级。
