[Knee stability after anterior cruciate ligament reconstruction with weight-bearing magnetic resonance imaging].

Objective: To investigate the application value of the weight-bearing magnetic resonance imaging (MRI) in evaluating the stability of knee joint after anterior cruciate ligament reconstruction. Methods: From July 2011 to August 2013, a total of 25 patients with anterior cruciate ligament rupture and reconstruction surgery in the Second Affiliated Hospital of Soochow University were enrolled in this study, including 18 males and 7 females, with an average age of (32±5) years. All the patients underwent the weight-bearing MRI, knee joint passive relaxation test (Kneelax 3), and Lysholm score before the surgery and 3 and 6 months after the surgery. The three examinations before and after the operation were analyzed by repeated measures of general linear model, and paired t test was used to compare the results before and after the operation. The correlation between the three preoperative examinations was statistically analyzed. Results: The relaxation data measured by Kneelax 3 after the surgery was significantly lower than that before the operation [(1.1±0.9) mm vs (6.1±1.3) mm, t=16.9, P<0.01]. The post-operative lateral tibial plateau anterior shift score was less than the pre-operative score [(3.0±0.7) mm vs (4.8±1.2) mm, t=6.2, P<0.01]. The post-operative Lysholm score was significantly higher than that before the operation (89±6 vs 64±14, t=-8.3, P<0.05). There was a negative correlation between the anterior displacement of the lateral platform and Lysholm score (r=-0.902, P<0.01). There was no correlation between anterior displacement and passive relaxation of the lateral platform in preoperative weight-bearing MRI. Conclusions: Anterior cruciate ligament reconstruction can improve the knee stability. The stability of knee joint can be evaluated by weight-bearing MRI. The anterior tibial displacement measured by the weight-bearing MRI is correlated with the clinical score.目的： 探讨负重位磁共振评估前交叉韧带损伤及重建后的膝关节稳定性的应用价值。 方法： 选择2011年7月至2013年8月25例前交叉韧带断裂并在苏州大学附属第二医院进行重建手术的患者，其中男18例，女7例，平均年龄（32±5）岁。分别在术前和术后3、6个月进行膝关节的负重位磁共振检查，膝关节被动松弛度测量（Kneelax 3）和Lysholm评分，负重位磁共振检查测量患膝胫骨与健侧相比前移的距离。对术前、术后的结果采用重复测量的方差分析，同时采用配对t检验进行手术前后比较，术前的三种检查间分别进行相关性分析统计。 结果： 术后Kneelax 3测得松弛度为（1.1±0.9）mm，明显小于术前的（6.1±1.3）mm（t=16.9，P<0.01）。术后负重位磁共振的胫骨外侧平台前移度为（3.0±0.7）mm，小于术前的（4.8±1.2）mm（t=6.2，P<0.01）。术后膝关节Lysholm评分为（89±6）分，显著高于术前的（64±14）分（t=-8.3，P<0.05）。术前负重位磁共振外侧平台的前移度和Lysholm评分呈负相关（r=-0.902，P<0.01）。术前负重位磁共振外侧平台的前移度和被动松弛度无相关性。 结论： 前交叉韧带重建手术可改善膝关节稳定性。负重位磁共振测量的胫骨前移度和临床评分结果具有相关性，可考虑用负重位磁共振的方法评估膝关节的稳定性。.