Department of Orthopaedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
Albert Einstein College of Medicine, Bronx, New York, USA.
Am J Sports Med. 2019 Feb;47(2):277-284. doi: 10.1177/0363546518812435. Epub 2018 Dec 7.
In anterior cruciate ligament-deficient (ACL-D) knees, injury pattern and bony morphologic features have been shown to influence both static anterior tibial subluxation relative to the femur and dynamic rotatory knee laxity. Therefore, the relationship between static anterior tibial subluxation and dynamic rotatory knee laxity was investigated.
To determine whether static tibial subluxation as measured on magnetic resonance imaging (MRI) is associated with the grade of rotatory knee laxity in ACL-D knees.
Cross-sectional study; Level of evidence, 3.
Two-hundred fifty-eight knees underwent preoperative, image-guided assessment of lateral knee compartment translation during quantitative pivot shift (QPS). Subluxations of the medial and lateral tibial plateaus were measured on preoperative MRI in a subset of primary ACL-D knees meeting criteria for high-grade (QPS > 5.2 mm) and low-grade (QPS < 2.4 mm) rotatory laxity. Tibial subluxations on MRI were compared between patients with high- and low-grade rotatory laxity through use of pairwise t test and were analyzed via univariate and multivariate logistic regression. Significance was set at P < .05.
On MRI, greater anterior subluxation of the lateral tibial plateau was observed in patients with high-grade compared with low-grade rotatory knee laxity (4.5 mm vs 2.3 mm; P < .05). No similar relationship was observed for the medial tibial plateau (-0.9 mm vs -0.4 mm; P > .05). Univariate logistic regression demonstrated that static subluxation of the lateral tibial plateau was associated with high-grade rotatory knee laxity (odds ratio [OR], 1.2; P < .05). An optimal cutoff of 2.95 mm of static lateral tibial subluxation was associated with high-grade rotatory knee laxity (sensitivity, 75%; specificity, 63%). Lateral meniscal injury was the first variable entered into a multivariate regression analysis and proved to be most associated with high-grade rotatory knee laxity (OR, 6.8; P < .05). When lateral meniscal injury was excluded from multivariate regression analysis, static anterior subluxation of the lateral tibial plateau alone was associated with high-grade rotatory knee laxity (OR, 1.2; P < .05).
Data from this MRI study of two distinct rotatory knee laxity groups showed that static anterior subluxation of the lateral tibial plateau of 2.95 mm or greater was associated with high-grade rotatory knee laxity, and each millimeter increase of lateral tibial plateau subluxation was associated with a 1.2-fold odds of high-grade rotatory knee laxity. Anterior subluxation of the lateral tibial plateau on MRI was not independently associated with high-grade rotatory knee laxity in the presence of concomitant lateral meniscal injury. Static measurements made preoperatively may aid in predicting high-grade rotatory knee laxity and refining the indications for individualized knee surgery.
在前交叉韧带缺失（ACL-D）的膝关节中，损伤模式和骨形态特征已被证明会影响相对于股骨的静态胫骨前侧半脱位和动态旋转膝关节松弛。因此，研究了静态胫骨前侧半脱位与动态旋转膝关节松弛之间的关系。
确定 MRI 测量的静态胫骨前侧半脱位是否与 ACL-D 膝关节的旋转膝关节松弛程度有关。
横断面研究；证据水平，3 级。
258 例膝关节接受了术前、图像引导的定量枢轴转移（QPS）时外侧膝关节间隔平移评估。在符合高等级（QPS > 5.2mm）和低等级（QPS < 2.4mm）旋转松弛标准的原发性 ACL-D 膝关节中，对内侧和外侧胫骨平台的半脱位进行了术前 MRI 测量。使用配对 t 检验比较高、低等级旋转松弛患者的 MRI 胫骨半脱位，并通过单变量和多变量逻辑回归进行分析。设定 P <.05 为有统计学意义。
在 MRI 上，与低等级旋转膝关节松弛相比，高等级旋转膝关节松弛患者的外侧胫骨平台的前侧半脱位更大（4.5mm 比 2.3mm；P <.05）。内侧胫骨平台未观察到类似的关系（-0.9mm 比-0.4mm；P >.05）。单变量逻辑回归表明，外侧胫骨平台的静态半脱位与高等级旋转膝关节松弛有关（优势比[OR]，1.2；P <.05）。静态外侧胫骨平台 2.95mm 的最佳截断值与高等级旋转膝关节松弛相关（灵敏度，75%；特异性，63%）。外侧半月板损伤是进入多变量回归分析的第一个变量，与高等级旋转膝关节松弛的关系最密切（OR，6.8；P <.05）。当将外侧半月板损伤排除在多变量回归分析之外时，单独的外侧胫骨平台前侧半脱位与高等级旋转膝关节松弛有关（OR，1.2；P <.05）。
这项对两个不同旋转膝关节松弛组的 MRI 研究的数据表明，外侧胫骨平台的静态前侧半脱位 2.95mm 或更大与高等级旋转膝关节松弛有关，外侧胫骨平台半脱位每增加 1mm，高等级旋转膝关节松弛的几率就增加 1.2 倍。在存在外侧半月板损伤的情况下，外侧胫骨平台的 MRI 前侧半脱位与高等级旋转膝关节松弛无关。术前的静态测量可能有助于预测高等级旋转膝关节松弛，并细化个体化膝关节手术的适应证。
