■已知踝关节中的压力分布取决于各种因素,包括后脚对齐。我们试图评估在旋起外旋(SER)型踝关节骨折的设置中,后足对齐如何影响踝关节的接触压力。
■在10个人体尸体下肢标本中产生了SER骨折,模拟损伤的进展阶段:没有骨折(步骤0),SER骨折和完整的三角肌韧带(步骤1),三角肌浅韧带断裂(第2步),和深三角肌韧带破坏(第3步)。在每一步,通过将跟骨结节内侧或外侧移位7mm来模拟内翻和外翻对齐。每个肢体在每次截骨后以350N的静载荷轴向加载。力中心(COF),接触面积(CA),并测量了负载下的峰值接触压力(PP),并对踝关节的X线照片进行分析,以分析内侧透明空间(MCS)和距骨倾斜(TT)。
■COF(5.3毫米,P=.030)和CA(-188.4mm2,P=.015)在第3步中与基线参数相比在后足外翻对齐中发生了变化,表明深三角肌韧带完整性在维持足外翻正常踝关节接触应力中的重要性。这些变化在内翻对齐设置中没有看到(COF:2.3mm,P=.059;CA-121mm2,P=.133)。发现PP在内翻或外翻中都没有显着变化(内翻:-4.9N,P=.132;外翻:-4N,P=.464)。与步骤2(0.7毫米,P=.020)后脚内翻和外翻。后足外翻的第3步中TT显着增加(2.8度,P=.020)与步骤0相比。
■与后足内翻对齐的SER-IV骨折相比,具有后足外翻对齐的SER-IV骨折显示出压力分布和影像学参数的显着变化。
■基于此尸体建模研究,SERIV骨折后足内翻对齐和完整的三角韧带病变的患者可能不需要骨折固定术,而那些后足外翻对齐的人可能需要骨折固定术。
UNASSIGNED: Pressure distribution in the ankle joint is known to be dependent on various factors, including hindfoot alignment. We seek to evaluate how hindfoot alignment affects contact pressures in the ankle joint in the setting of supination external rotation (SER) type ankle fractures.
UNASSIGNED: SER fractures were created in 10 human cadaver lower extremity specimens, simulating progressive stages of injury: without fracture (step 0), SER fracture and intact deltoid ligament (step 1), superficial deltoid ligament disruption (step 2), and deep deltoid ligament disruption (step 3). At each step, varus and valgus alignment was simulated by displacing the calcaneal tuberosity 7 mm medial or lateral. Each limb was axially loaded following each osteotomy at a static load of 350 N. The center of force (COF), contact area (CA), and peak contact pressure (PP) under load were measured, and radiographs of the ankle mortise were taken to analyze the medial clear space (MCS) and talar tilt (TT).
UNASSIGNED: The COF (5.3 mm, P = .030) and the CA (-188.4 mm2, P = .015) changed in step 3 in the valgus hindfoot alignment compared to baseline parameters, indicating the importance of deep deltoid ligament integrity in maintaining normal ankle joint contact stress in the valgus hindfoot. These changes were not seen in the setting of varus alignment (COF: 2.3 mm, P = .059; CA -121 mm2, P = .133). PP were found to not change significantly in either varus or valgus (varus: -4.9 N, P = .132; valgus: -4 N, P = .464).The MCS demonstrated widening in step 3 compared to step 2 (0.7 mm, P = .020) in both varus and valgus hindfoot. The TT increased significantly in step 3 in the valgus hindfoot (2.8 degrees, P = .020) compared to step 0.
UNASSIGNED: SER-IV fractures with valgus hindfoot alignment showed significant changes in pressure distribution and radiographic parameters when compared to SER-IV fractures with varus hindfoot alignment.
UNASSIGNED: Based on this cadaver modeling study, patients with SERIV fracture with varus hindfoot alignment and complete deltoid ligament lesion may not need fracture fixation, whereas those with valgus hindfoot alignment likely need fracture fixation.