Department of Orthopedics, Balgrist University Hospital, University of Zurich, Forchstrasse 340, 8008, Zurich, Switzerland.
Department of Radiology, Balgrist University Hospital, University of Zurich, Forchstrasse 340, 8008, Zurich, Switzerland.
BMC Musculoskelet Disord. 2022 Mar 18;23(1):262. doi: 10.1186/s12891-022-05218-8.
Assessment of combined anterolateral ligament (ALL) and anterior cruciate ligament (ACL) injury remains challenging but of high importance as the ALL is a contributing stabilizer of tibial internal rotation. The effect of preoperative static tibial internal rotation on ACL -length remains unknown. The aim of the study was analyze the effect of tibial internal rotation on ACL length in single-bundle ACL reconstructions and to quantify tibial internal rotation in combined ACL and ALL injuries.
The effect of tibial internal rotation on ACL length was computed in a three-dimensional (3D) model of 10 healthy knees with 5° increments of tibial internal rotation from 0 to 30° resulting in 70 simulations. For each step ACL length was measured. ALL injury severity was graded by a blinded musculoskeletal radiologist in a retrospective analysis of 61 patients who underwent single-bundle ACL reconstruction. Preoperative tibial internal rotation was measured in magnetic resonance imaging (MRI) and its diagnostic performance was analyzed.
ACL length linearly increased 0.7 ± 0.1 mm (2.1 ± 0.5% of initial length) per 5° of tibial internal rotation from 0 to 30° in each patient. Seventeen patients (27.9%) had an intact ALL (grade 0), 10 (16.4%) a grade 1, 21 (34.4%) a grade 2 and 13 (21.3%) a grade 3 injury of the ALL. Patients with a combined ACL and ALL injury grade 3 had a median static tibial internal rotation of 8.8° (interquartile range (IQR): 8.3) compared to 5.6° (IQR: 6.6) in patients with an ALL injury (grade 0-2) (p = 0.03). A cut-off > 13.3° of tibial internal rotation predicted a high-grade ALL injury with a specificity of 92%, a sensitivity of 30%; area under the curve (AUC) 0.70 (95% CI: 0.54-0.85) (p = 0.03) and an accuracy of 79%.
ACL length linearly increases with tibial internal rotation from 0 to 30°. A combined ACL and high-grade ALL injury was associated with greater preoperative tibial internal rotation. This potentially contributes to unintentional graft laxity in ACL reconstructed patients, in particular with concomitant high-grade ALL tears.
Cohort study; Level of evidence, 3.
评估前交叉韧带（ACL）和前外侧韧带（ALL）的联合损伤仍然具有挑战性，但非常重要，因为 ALL 是胫骨内旋的稳定器。术前胫骨内旋对 ACL 长度的影响尚不清楚。本研究的目的是分析单束 ACL 重建中胫骨内旋对 ACL 长度的影响，并量化 ACL 和 ALL 联合损伤中的胫骨内旋。
通过 10 个健康膝关节的三维（3D）模型计算胫骨内旋对 ACL 长度的影响，胫骨内旋从 0 度增加 5 度至 30 度，共 70 个模拟。在每个步骤中测量 ACL 长度。在对 61 例接受单束 ACL 重建的患者进行的回顾性分析中，由一位经验丰富的肌肉骨骼放射科医生对 ALL 损伤的严重程度进行分级。在 MRI 中测量术前胫骨内旋，并分析其诊断性能。
在每个患者中，从 0 度到 30 度，胫骨内旋每增加 5 度，ACL 长度线性增加 0.7±0.1mm（初始长度的 2.1±0.5%）。17 例患者（27.9%）ALL 完整（0 级），10 例（16.4%）ALL 损伤 1 级，21 例（34.4%）ALL 损伤 2 级，13 例（21.3%）ALL 损伤 3 级。合并 ACL 和 ALL 损伤 3 级的患者，胫骨内旋的中位数为 8.8°（四分位距（IQR）：8.3），而 ALL 损伤（0-2 级）患者的胫骨内旋中位数为 5.6°（IQR：6.6）（p=0.03）。胫骨内旋>13.3°的截点可预测 ALL 损伤程度较高，特异性为 92%，灵敏度为 30%；曲线下面积（AUC）为 0.70（95%CI：0.54-0.85）（p=0.03），准确性为 79%。
ACL 长度随胫骨内旋从 0 度线性增加至 30 度。ACL 和高等级 ALL 联合损伤与术前胫骨内旋增加有关。这可能导致 ACL 重建患者的移植物松弛，尤其是合并高等级 ALL 撕裂时。
队列研究；证据水平，3 级。
