Baylor University Medical Center, Dallas, TX, USA.
Foot Ankle Int. 2013 Nov;34(11):1479-85. doi: 10.1177/1071100713494381. Epub 2013 Jun 17.
One of the rationales for total ankle arthroplasty (TAA) is that it may retard the changes of hypermobility and accelerated arthritis in the hindfoot after ankle arthrodesis. Until recently, it has not been possible to quantify or even objectively demonstrate biomechanical findings to substantiate the theory that postsurgical biomechanical changes in the ankle produce changes in the kinematics of the hindfoot. Standard gait analysis has treated the foot as a single biomechanical unit. This study was undertaken to describe the hindfoot motion following Scandinavian Total Ankle Replacement (STAR) TAA by using multisegment foot model gait analysis.
Forty-six patients with a mean age of 66 years underwent a 3D gait analysis following TAR. Mean interval between surgery and gait analysis was 4.9 years (range 2 to 9). The contralateral limb was used as control for each patient. Temporospatial variables and kinematic parameters were studied.
Temporospatial results showed statistically significant differences. Stance time on the affected side was 61.1% ± 2.2% of the gait cycle compared to 63.2% ± 2.1% for the unaffected side. Step length was 55.6 cm ± 10 on the affected side compared to 53.9 cm ± 10 for the unaffected side. Kinematics results were statistically significant: Ankle range of motion (ROM) on the arthroplasty side was 16.8 ± 4.5 degrees compared to 23.6 ± 5.0 on the unaffected side. Sagittal plane ROM was 12.7 ± 4.2 degrees on the arthroplasty side and 17.3 ± 3.5 degrees on the unaffected side. Coronal plane ROM was 4.7 ± 2.4 degrees on the arthroplasty side and 7.5 ± 2.4 degrees on the unaffected side. Transverse plane ROM on the arthroplasty side was 4.1 ± 1.5 degrees and 4.9 ± 1.6 on the unaffected side.
This study showed that, in addition to previously documented diminution in sagittal plane motion and gait velocity, some of the residual abnormalities of gait following TAR were comprised of differences in hindfoot function. These results relate to the growing recognition of the importance of understanding hindfoot mechanics apart from those of the tibiotalar joint.
Level III, comparative case series.
全踝关节置换术（TAA）的一个理论依据是，它可能会延缓踝关节融合术后后足过度活动和加速性关节炎的变化。直到最近，人们还无法量化甚至客观地证明生物力学发现，以证实踝关节术后生物力学变化会导致后足运动学的变化。标准步态分析将足部视为一个单一的生物力学单位。本研究旨在通过多节段足部模型步态分析来描述 Scandinavian Total Ankle Replacement（STAR）TAA 后的后足运动。
46 例平均年龄 66 岁的患者接受了 TAR 后的 3D 步态分析。手术与步态分析之间的平均间隔时间为 4.9 年（范围 2 至 9 年）。每位患者均以对侧肢体作为对照。研究了时间-空间变量和运动学参数。
时间-空间结果显示存在统计学差异。患侧的支撑期时间占步态周期的 61.1%±2.2%，而健侧为 63.2%±2.1%。患侧步长为 55.6cm±10cm，而健侧为 53.9cm±10cm。运动学结果具有统计学意义：患侧踝关节的活动范围（ROM）为 16.8°±4.5°，而健侧为 23.6°±5.0°。矢状面 ROM 为患侧 12.7°±4.2°，健侧 17.3°±3.5°。冠状面 ROM 为患侧 4.7°±2.4°，健侧 7.5°±2.4°。患侧横向平面 ROM 为 4.1°±1.5°，健侧为 4.9°±1.6°。
本研究表明，除了先前记录的矢状面运动和步态速度减小外，TAR 后步态的一些残留异常还包括后足功能的差异。这些结果与越来越认识到了解除距下关节以外的后足力学的重要性有关。
III 级，比较病例系列。
