Takahashi Katsunori, Teramoto Atsushi, Murahashi Yasutaka, Nabeki Shogo, Shiwaku Kousuke, Kamiya Tomoaki, Watanabe Kota, Yamashita Toshihiko
Department of Orthopaedic Surgery, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, Japan.
Department of Physical Therapy, Sapporo Medical University School of Health Sciences, Sapporo, Hokkaido, Japan.
Orthop J Sports Med. 2022 Sep 13;10(9):23259671221122811. doi: 10.1177/23259671221122811. eCollection 2022 Sep.
Studies on ankle syndesmosis have focused on anterior inferior tibiofibular ligament (AITFL) and interosseous membrane injuries; however, the characteristics of posterior inferior tibiofibular ligament (PITFL) ruptures remain unclear.
PURPOSE/HYPOTHESIS: This study evaluated the biomechanical characteristics of syndesmotic instability caused by PITFL injury and compared various treatment methods. We hypothesized that PITFL injury would lead to syndesmotic internal rotational instability and that the stability would be restored with suture tape (ST) PITFL augmentation.
Controlled laboratory study.
Ten uninjured fresh-frozen cadaveric leg specimens were tested via forces applied to the external and internal rotation of the ankle joint. The fibular rotational angle (FRA) related to the tibia, anterior tibiofibular diastasis (aTFD), and posterior tibiofibular diastasis (pTFD) were measured using a magnetic tracking system. Six models were created: (1) intact, (2) AITFL injury; (3) AITFL + PITFL injury; (4) suture button (SB) fixation; (5) SB + anterior ST (aST) fixation; and (6) SB + aST + posterior ST fixation. The FRA, aTFD, and pTFD were statistically compared between the intact ankle and each injury or fixation model.
In the intact state, the changes in FRA and aTFD were 1.09° and 0.33 mm when external rotation force was applied and were 0.57° and 0.41 mm when internal rotation force was applied. In the AITFL injury model, the changes in FRA and aTFD were 2.38° and 1.51 mm when external rotation force was applied, which were significantly greater versus intact ( = .032 and .008, respectively). In the AITFL + PITFL injury model, the changes in FRA and pTFD were 2.12° and 1.02 mm when internal rotation force was applied, which were significantly greater versus intact ( = .007 and .003, respectively). In the SB fixation model, the change in FRA was 2.98° when external rotation force was applied, which was significantly higher compared with intact ( < .001). There were no significant differences between the SB + aST fixation model and the intact state on any measurement.
PITFL injury significantly increased syndesmotic instability when internal rotation force was applied. SB + aST fixation was effective in restoring syndesmotic stability.
These results suggest that SB + aST fixation is sufficient for treating severe syndesmotic injury with PITFL rupture.
关于踝关节下胫腓联合的研究主要集中在前下胫腓韧带（AITFL）和骨间膜损伤；然而，后下胫腓韧带（PITFL）断裂的特征仍不明确。
目的/假设：本研究评估了PITFL损伤导致的下胫腓联合不稳定的生物力学特征，并比较了各种治疗方法。我们假设PITFL损伤会导致下胫腓联合内旋不稳定，并且通过缝线带（ST）增强PITFL可恢复稳定性。
对照实验室研究。
对10个未受伤的新鲜冷冻尸体小腿标本施加踝关节内、外旋力进行测试。使用磁跟踪系统测量腓骨相对于胫骨的旋转角度（FRA）、胫腓前间隙（aTFD）和胫腓后间隙（pTFD）。创建了6个模型：（1）完整；（2）AITFL损伤；（3）AITFL + PITFL损伤；（4）缝线纽扣（SB）固定；（5）SB + 前ST（aST）固定；（6）SB + aST + 后ST固定。对完整踝关节与每个损伤或固定模型的FRA、aTFD和pTFD进行统计学比较。
在完整状态下，施加外旋力时FRA和aTFD的变化分别为1.09°和0.33 mm，施加内旋力时分别为0.57°和0.41 mm。在AITFL损伤模型中，施加外旋力时FRA和aTFD的变化分别为2.38°和1.51 mm，与完整状态相比显著更大（分别为P = 0.032和0.008）。在AITFL + PITFL损伤模型中，施加内旋力时FRA和pTFD的变化分别为2.12°和1.02 mm，与完整状态相比显著更大（分别为P = 0.007和0.003）。在SB固定模型中，施加外旋力时FRA的变化为2.98°，与完整状态相比显著更高（P < 0.001）。SB + aST固定模型与完整状态在任何测量上均无显著差异。
施加内旋力时，PITFL损伤显著增加下胫腓联合不稳定。SB + aST固定可有效恢复下胫腓联合稳定性。
这些结果表明，SB + aST固定足以治疗伴有PITFL断裂的严重下胫腓联合损伤。
