Department of Orthopaedic Surgery, Graduate School of Medicine, Kobe University, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Knee Surg Sports Traumatol Arthrosc. 2019 Nov;27(11):3426-3431. doi: 10.1007/s00167-019-05376-8. Epub 2019 Feb 4.
The purpose of this study was to quantitatively compare the results of pivot-shift test between knees with anterior cruciate ligament (ACL) injury with and without anterolateral capsule (ALC) injury detected on MRI. ALC injury was hypothesized to worsen rotatory knee laxity.
82 patients with unilateral ACL injury were enrolled in this study. The pivot-shift test was performed under anesthesia before ACL reconstruction. Two evaluations were conducted simultaneously: IKDC clinical grading and the quantitative evaluation using an electromagnetic measurement system that determined tibial acceleration (m/s). Two examiners identified the ALC injury on magnetic resonance imaging (MRI) and stratified patients into two groups: ALC-injured (ALC+) and ALC-intact (ALC-). ALC injury was diagnosed if the signal intensity on coronal T2-weighted sequences is increased. After confirming the reliability of the MRI, the difference in the pivot-shift between two groups was assessed.
Because of the poor agreement between examiners with respect to the ALC evaluations (κ coefficient of 0.25 and 58.5% concordance), the result from each examiner was analyzed separately. Examiner 1 found ALC injury in 42/82 knees (51%). The two groups had similar clinical grading (glide/clunk/gross: ALC+ group 21/18/3cases vs. ALC- group 21/16/3cases) (n.s.). Tibial acceleration during pivot-shift was also similar in the ALC+ (1.4 ± 1.2 m/s) and ALC- (1.7 ± 1.3 m/s) groups (n.s.). Examiner 2 found ALC injury in 28/82 knees (34%). Differences in clinical grading were not observed (glide/clunk/gross: ALC+ group 16/9/3 vs. ALC- group 26/25/3) (n.s.). However, the tibial acceleration in the ALC+ group (1.2 ± 0.8 m/s) was significantly lower than that in the ALC- group (1.7 ± 1.3 m/s, p = 0.03).
Concomitant ALC injury in knees with ACL injury was not consistently detected on MRI and did not affect rotatory knee laxity.
Case-control study, level III.
本研究旨在定量比较 MRI 检测到合并与不合并前外侧囊（ALC）损伤的前交叉韧带（ACL）损伤膝关节的髌股关节（Pivot-shift）试验结果。假设 ALC 损伤会加重膝关节的旋转不稳定性。
本研究纳入了 82 例单侧 ACL 损伤患者。在 ACL 重建前，在全身麻醉下进行 Pivot-shift 试验。同时进行两项评估：IKDC 临床分级和使用电磁测量系统进行的定量评估，该系统确定胫骨加速度（m/s）。两名评估者在磁共振成像（MRI）上识别 ALC 损伤，并将患者分为两组：ALC 损伤组（ALC+）和 ALC 未损伤组（ALC-）。如果冠状位 T2 加权序列上的信号强度增加，则诊断为 ALC 损伤。在确认 MRI 的可靠性后，评估两组之间的 Pivot-shift 差异。
由于评估者对 ALC 评估的一致性较差（κ 系数为 0.25，一致性为 58.5%），因此分别分析了每位评估者的结果。评估者 1 在 82 个膝关节中发现 42 个（51%）ALC 损伤。两组的临床分级相似（滑动/弹响/明显：ALC+组 21/18/3 例，ALC-组 21/16/3 例）（无统计学意义）。ALC+（1.4±1.2 m/s）和 ALC-（1.7±1.3 m/s）组的 Pivot-shift 期间胫骨加速度也相似（无统计学意义）。评估者 2 在 82 个膝关节中发现 28 个（34%）ALC 损伤。临床分级差异无统计学意义（滑动/弹响/明显：ALC+组 16/9/3 例，ALC-组 26/25/3 例）（无统计学意义）。然而，ALC+组的胫骨加速度（1.2±0.8 m/s）明显低于 ALC-组（1.7±1.3 m/s，p=0.03）。
ACL 损伤膝关节的合并 ALC 损伤在 MRI 上并未一致检测到，并且不会影响膝关节的旋转不稳定性。
病例对照研究，III 级。
