Fitzpatrick Daniel C, Sommers Mark B, Kam Benjamin C C, Marsh J Lawrence, Bottlang Michael
Orthpedic Healthcare Northwest, Eugene, Oregon, USA.
Am J Sports Med. 2005 Nov;33(11):1735-41. doi: 10.1177/0363546505275132. Epub 2005 Aug 10.
Articulated external fixation has been proposed as a method to protect ligament reconstructions while allowing aggressive and early postoperative rehabilitation after knee dislocation. However, the ability of these fixators to protect and stabilize the knee joint has not been clearly determined.
Articulated external fixation can reduce anteroposterior translation in the cruciate-deficient knee and reduce cruciate ligament strain in cases of intact or reconstructed ligaments.
Controlled laboratory study.
Knee stability was assessed by 3 standard clinical stability tests (Lachman, anterior drawer, and posterior drawer) on 7 human cadaveric lower extremities. Instrumented forces of 100 N were applied to the tibia to measure cruciate ligament forces and tibiofemoral displacement in intact and cruciate-deficient specimens with and without articulated external fixation to determine the degree to which a fixator can protect cruciate ligaments and stabilize the knee. Articulated external fixation was applied using monolateral and bilateral fixators to comparatively analyze the effectiveness of each construct. Statistical analysis was performed using 2-tailed, paired Student t tests.
Application of the monolateral articulated external fixator to specimens with intact ligaments significantly reduced cruciate ligament forces by 1.0 N (P = .011), 1.7 N (P = .046), and 1.4 N (P = .009) for Lachman, anterior drawer, and posterior drawer tests, respectively. In the cruciate ligament-deficient knees, the application of a monolateral fixator significantly reduced tibiofemoral translation by 49%, 70%, and 46% for Lachman, anterior drawer, and posterior drawer tests, respectively. No significant differences between the monolateral and bilateral fixator frames, in terms of ligament protection and joint stabilization, were observed.
Articulated external fixation of the knee can reduce stress in the cruciate ligaments after multiligament reconstructions and can decrease anteroposterior translation in the cruciate-deficient knee.
关节式外固定已被提议作为一种保护韧带重建的方法，同时允许在膝关节脱位后进行积极且早期的术后康复。然而，这些固定器保护和稳定膝关节的能力尚未明确确定。
关节式外固定可减少交叉韧带缺失膝关节的前后移位，并在韧带完整或重建的情况下减少交叉韧带应变。
对照实验室研究。
对7具人体尸体下肢进行3项标准临床稳定性测试（拉赫曼试验、前抽屉试验和后抽屉试验）以评估膝关节稳定性。对完整和交叉韧带缺失的标本施加100 N的仪器力，在有和没有关节式外固定的情况下测量交叉韧带力和胫股位移，以确定固定器保护交叉韧带和稳定膝关节的程度。使用单侧和双侧固定器应用关节式外固定，以比较分析每种结构的有效性。采用双尾配对学生t检验进行统计分析。
对于拉赫曼试验、前抽屉试验和后抽屉试验，将单侧关节式外固定器应用于韧带完整的标本时，交叉韧带力分别显著降低1.0 N（P = 0.011）、1.7 N（P = 0.046）和1.4 N（P = 0.009）。在交叉韧带缺失的膝关节中，对于拉赫曼试验、前抽屉试验和后抽屉试验，应用单侧固定器分别使胫股移位显著减少49%、70%和46%。在韧带保护和关节稳定方面，未观察到单侧和双侧固定器框架之间存在显著差异。
膝关节的关节式外固定可减少多韧带重建后交叉韧带的应力，并可减少交叉韧带缺失膝关节的前后移位。
