Department of Sports Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
Knee Surgery Department of the Institute of Sports Medicine & Beijing Key Laboratory of Sports Injuries, Peking University Third Hospital, Beijing, China.
Arthroscopy. 2021 Apr;37(4):1182-1191. doi: 10.1016/j.arthro.2020.10.038. Epub 2020 Nov 20.
To analyze the contribution of a secondary anterolateral structure (ALS) deficiency to knee instability based on anterior cruciate ligament (ACL) deficiency, in the condition of a functional iliotibial band (ITB).
Nine freshly-frozen cadaveric knees were sectioned sequentially to create ACL deficiency and ACL-ALS deficiency, using intact knees before sectioning as controls. When ITB was tensioned with 30 N, 4 separate aspects of knee instability were tested as follows: anterior translation in 90 N anterior load, isolated internal rotation in 5 N·m internal rotational torque from 0° to 90° in 15° increments, and anterolateral translation and internal rotation during a simulated pivot-shift test at 0°, 15°, 30°, and 45°. The contribution of ACL deficiency alone and additional ALS deficiency to knee instability were evaluated.
The addition of an ALS lesion produced no significant exacerbation of either anterior translational or pivot shift instability in ACL-deficient knees. Additional ALS deficiency in an ACL-deficient knee resulted in a significant increase in isolated internal rotation from 45° to 90° (P = .001 at 45° and P < .001 in other cases). After sequentially sectioning, the contribution to instability of additional ALS deficiency to the entire instability in ACL-ALS-deficient knees was significantly smaller than that of ACL deficiency alone during anterior load and pivot-shift test (P < .001 in all cases), but significantly contributed more to isolated internal rotational instability at 60° (P = .011) and 90° (P = .015).
When ITB was tensioned, ALS played a minor role in controlling both anterior or pivot shift stability in ACL-deficient knees but a major role in restraining isolated internal rotation from 45° to 90°.
In the condition of functional ITB, concomitant ALS injury might not exacerbate anterior and pivot-shift instability after ACL rupture, while affecting isolated internal rotation stability at higher flexion.
分析在功能性髂胫束（ITB）条件下，前交叉韧带（ACL）缺陷基础上，次要前外侧结构（ALS）缺陷对膝关节不稳定的贡献。
对 9 个新鲜冷冻的尸体膝关节进行连续节段性切除，建立 ACL 缺陷和 ACL-ALS 缺陷，在节段性切除前用完整的膝关节作为对照。当 ITB 在 30N 张力下，测试膝关节的 4 个不同不稳定方面如下：在 90N 前负荷下的前向平移，0°至 90°每隔 15°递增 5N·m 内旋转扭矩时的单纯内旋，以及在 0°、15°、30°和 45°模拟枢轴转移试验时的前外侧平移和内旋。评估 ACL 缺陷单独和附加 ALS 缺陷对膝关节不稳定的影响。
在 ACL 缺陷膝关节中，附加 ALS 病变并没有显著加重前向平移或枢轴转移不稳定。在 ACL 缺陷膝关节中附加 ALS 缺陷会导致从 45°到 90°的单纯内旋显著增加（45°时 P=.001，其他情况下 P<.001）。在连续节段性切除后，在 ACL-ALS 缺陷膝关节中，附加 ALS 缺陷对整个不稳定的不稳定的影响明显小于 ACL 缺陷单独在前负荷和枢轴转移试验中的影响（所有情况下 P<.001），但在 60°和 90°时对内旋不稳定的影响明显更大（60°时 P=.011，90°时 P=.015）。
当 ITB 被拉紧时，ALS 在控制 ACL 缺陷膝关节的前向或枢轴转移稳定性方面作用较小，但在限制从 45°到 90°的单纯内旋稳定性方面作用较大。
在功能性 ITB 的情况下，ACL 断裂后伴随 ALS 损伤可能不会加重前向和枢轴转移不稳定，但会影响更高屈曲位的单纯内旋稳定性。
